Dodge D15T

[64EK26]

Hi Pete

Very informative and good advice.

Also suggest that if you are going to refit them, then mark up which way round the the con rod and piston are orientated so you can put them back exactly the way they came out of the block and and off the crank shaft.

Interesting profile on the pistions that lets the oil though the "oil control scraper" ring at the bottom of the piston

Cheers

Richard

[Pete Ashby]

3 minutes ago, 64EK26 said:

Hi Pete

Interesting profile on the pistions that lets the oil though the "oil control scraper" ring at the bottom of the piston

Cheers

Richard

Good evening Richard trust all is well with you ?

just goes to show how many variations on a standard theme there can be,  and that's before we get into piston crown design and material ie flat top, dome top, concave, scalloped,  Aluminium, cast iron,  plated, non plated  etc, etc 

Pete

[Pete Ashby]

With the festivities over, family departed and the head beginning to clear after a rather good batch of home brew thoughts have returned to what’s been going on in the workshop.

The last post looked at how the pistons rings and rods were disassembled the pistons, wrist pins and rods have been put to one side awaiting cleaning, inspection  and measuring, the rings will not be reused and have been bagged up and kept for reference purposes only.

It was now time to look critically at the block; first off the block face was cleaned up so that a quick visual inspection could be made for cracks or damage on the face and around the valve ports also a preliminary inspection of the bores.

You will find U tube videos of scoring pads fitted to a grinder being used for this.  It’s your call but it’s too aggressive for my liking so I do it this way….. slower…. but I don’t run the risk of dishing the block face by over eager use of the abrasive pad,  as I was once told, a ‘head gasket don’t give a dam how shiny the block or head surface is but they have to be flat’.

The basic tools I used for this part of the job are self-explanatory with possibly the exception item C in the photo below but for sake of completeness, I’ve listed them below.

A = Flat broad blade paint scrapper for removing gasket gunge and baked on oil.  I have slightly rounded off the corners of the blade so that it won’t dig in and scratch the surface

B= Craft knife blade used like another fine scrapper for finishing off this is held in the hand and used at 45 degrees to the face again with the points just nipped off on the bench grinder.

C= Spring loaded bore gauge being used as a quick check to see how much of a ridge there is at the top of the bore, more about this in another post to follow.

D= tap stock and 3/8 UNC 2^nd tap to clear all the head bolt threads out

E= Steel rod for poking out the water jacket holes

 

After working across the whole block face and good wash down with gun wash it looks like this

Pete

Edited January 21, 2022 by Pete Ashby

[Pete Ashby]

No horrors found on the block face or valve ports so the next job was to examine the outside of the block for cracks in the wall of the water jacket. If present these show up as faint linear rust stains, nothing visible using a magnifying glass so on to next step.

This involves removing the expansion plugs variously referred to as welch plugs or core plugs in the water jacket.

First a hole is drilled in the center of the plug large enough to take a parallel drift or fairly stout Philips screwdriver

That's whats going on here,  one of the bottom plugs has already been removed and a pilot hole drilled in the top one ready for the appropriate drill to be used for the punch or screw driver

 

Using the drift or screwdriver lever the plug out don’t use too much force as you may damage the block surround or the lip that the plug seats against.

 

There was a fair amount of sludge in the bottom of the jacket and that will be flushed out in due course using a pressure hose.

 

Pete

Edited January 21, 2022 by Pete Ashby

[Motleyholt]

Over cleaning and polishing head and block faces can be detrimental. The roughness is is intentional as it literally grips the head gasket. Where I used to work we machined Jaguar and Rover ally cylinder heads, we used a planer which was hand operated mill. Had something like a 300mm cutter with about 30 ceramic inserts in, running at a ferocious speed, and the cutting head was moved by hand over the cylinder head as fast as you could move it! Each cutting insert cost several hundred pounds.

I digressed a bit but careful cleaning is better and if it needs more a quick trip to the engine reconditioned will restore the correct surface.

Lovely work so far 👍

[Pete Ashby]

Next up was to inspect the bores, no scores or chunks out of the walls so that was a positive start and not too much of a ridge at the top of the cylinder.  Before I started to measure anything I ran the three legged hone up and down each bore a couple of times adjusted just to clean them up the idea was not to remove any metal just to remove the tarnish and a small amount of flash rust.

That's what's going on here,  some people use WD40 as a stone lubricant,  I prefer to use clean automatic transmission fluid applied to the cylinder walls with a brush. If you are going to have a go at this but not used a hone before go on the web or read a book it's a useful tool but you can over cook it and end causing more harm than good.

 

Now this next bit will cause some eyebrows to lift in some quarters but I prefer to use spring bore gauges rather than a dial bore gauge. 

In another 'Universe far far away'  I spent many hundreds of hours using these little gizmos, they take some practice to get good reproducible results with,   if used correctly will give reproducible results to within a thou which is fine for what I'm trying to determine here namely current bore size, out of round and taper conditions compared to factory standard specs which on these old style engines are by modern standards generous. 

If you want to spend a fair bit of cash buy yourself a dial bore gauge but unless you are going to be building engines day in day out it's a piece of kit you will not get much use out of.  Leave that to your machine shop is my advise.

What I'm trying to decide here is two fold. 

One,  does this block need to go to the machine shop ? 

 Two,  if the answer to one is yes then what are  my options in terms availability for oversize pistons and rings. This will enable an informed conversation with the machinist regarding oversize boring options.

The alternative is just give the whole lump to him and tell him to get on with it, which he will do, but be prepared for a pain in the chest and wallet when the bill arrives. 

I'm not going into how use the gauges there's plenty of info on the web if anyone is interested. Suffice to say I'm measuring each bore diameter at four points AA BB CC DD (chalk these on the door or wall to ensure you measure the same location each time for each level on the cylinder) and three heights relative to travel of the top ring,  top dead center (TDC) , mid stroke and bottom dead center (BDC). You can work this out by measuring the ring gap/ top land relationship and knowing the stroke length for the engine.

Here's the kit need for the task, micrometer, spring (telescopic) bore gauge and a results table drawn up to record the results so comparisons can be made and conclusions drawn. Glasses and a magnifying glass are optional for old gits if required.

 

Here I'm measuring one diameter at top ring TDC. 

I have marked the three depths in the bore that measurements are to be taken onto the handle of the bore gauge so the brass rule acts a datum point for this (top ring plus the depth of the top land as on this engine the crown is flush with the block deck at TDC)  this ensure as I move around the four points in the bore the measurement is taken at the same depth.

 

The gauge is locked off withdrawn careful and the measurement taken using the micrometer then recorded on the table in the correct location.  The variance from standard can now be calculated for each position.

  I use a small block of wood to place the gauge on while I use the micrometer. 

 

Quicker with a dial bore gauge ??.......  definitely yes ....... More accurate???.... yes if used correctly. 

However I rather like doing it this way and time is not an issue for me.  I'm not looking for definitive answers here. Rather  I'm just trying to get picture for whats been going on in the engine during it's operational life and what the options may be during rebuild. 

Pete

 

 

Edited February 4, 2022 by Pete Ashby

[Pete Ashby]

So after all this faffing about with gauges and some simple maths whats the conclusions ??. 

Bores are standard, showing some operational ware but still comfortably inside what would be required for re bore at plus 10 thou. They will clean with a three legged hone followed by a spherical hone to cross hatch the surface of the bore.

There is a perfectly valid school of thought that says do it once, do it right,  but I'm applying a degree of pragmatism here this is not an engine that is going to do 100K plus miles a year in truth it will not do a 1K a year.

   If there was excessive ware or damage it would be a forgone conclusion to machine, fortunately that is not the case here.

If the block went for re-bore then oversize pistons and rings would be required.  Dodge Chrysler spec is Std to 9 thou use Std pistons and rings,  10 to 19 thou use plus 10 thou pistons and rings and so at 10 thou intervals to 60 thou max.

Crank mains are standard and the journal faces are good,

Big end journals at minus 10 thou clean without burning or scoring

Wrist pins (piston pins) standard,  good to go again without undue ware measured at 3 points along their length

Little end bushes slightly over spec partly due I suspect to the lack of oil quality at some point 

Pistons in spec and good condition.

Cam shaft and bearings in spec in good condition

The upshot of all that is a new set of piston rings, new big end bearings at plus 10 thou, new main bearings at standard, new set of little end bushes and a full gasket set.

Which brings me to valves and seats,  poor running and starting issues can be the result of worn or damaged valves, seats and guides.  On a running engine a vacuum gauge is your best friend in determining a problem, there are hours of stuff on the web about how to use this very useful cheap bit of kit.  My old mechanical engineering books have some excellent fault finding charts on the use of a vacuum gauge where all manner of engine and ignition ills can be diagnosed.

This engine didn't run so it was down to measurement and visual inspection so I'll cover that in the next post.

Pete

 

Edited February 3, 2022 by Pete Ashby

[Pete Ashby]

Valves, what's to be said about them then?  they either work or they don't right ?  If the piston acts like a pump to suck the fuel air charge in that provides the power to make everything work then the valve train ( that's everything associated with the valves and operation) lets that charge in in the first place, keeps it there under high pressure then lets it out at the appropriate time, all this needs to be done at the right time and without leaks.  As with most things in life it's not that simple.

Poor starting, rough running, high oil consumption, smokey exhaust, popping back in the exhaust or spitting back up the carb are conditions that can be laid at the door in part or fully with problems associated with valves, seats, guides or springs or a pick n mix combination of any of those. This is when a the vacuum gauge I mentioned in the previous post can save hours of frustration,  that was not an option here as this engine was a non runner.

So first off all the valves are removed as previous posts in this blog

Quick visual recap here keep the valves in order as they are removed a piece of stout card or a block of wood are required for this

Do the same with the springs these will be cleaned up and inspected for broken or compressed coils and the free length (uncompressed) measured and compared across all twelve springs they all should be the same.  There is a way of measuring the compressed length as well using a block of wood a vice and a nail but it's all a bit scary.  If you want to try it go and search it out for yourselves.  Alternately take the springs to your machine shop and let him measure them with his spring compression gauge.

Each valve needs to be cleaned.   I use a brass wire brush to clean the carbon off of the head of the valve. If you don't have a lathe use the drill held in the vice, wrap a small section of gaffer tape round the portion of the stem held in the chuck to prevent damaging the stem.

Use a piece of medium grade Scottbright (like a synthetic pan scourer)  against the underside of valve to remove carbon and tarnish, try not to let it stray onto the seating surface of the valve then a couple of quick passes along the stem.

I finish off the stem with Auto solve chrome polish and a rag then wash everything off with solvent.

And they look like this you can see someone has been here before and punch  marked the head of inlet valve with four dots.

Inspect the valve head for damage, splits or burning if found its scrap and you need go no further other than splash the cash and get a replacement.  Measure the stem diameter in three places and compare with the manufactures spec then measure the valve guide using the smallest pipe gauge in the set ( in the same way I measured bores in a previous post ) . Inspect the corresponding seat in in either the block or head depending on your engine configuration again your looking for damage or excessive pitting, use a magnifying glass.

 

If all of the above checks out the next stage is grinding (lapping) the valve into the corresponding seat to make a gas tight seal that's what I'm getting ready to do here. 

I'm not going to cover the process in detail there's plenty of info out there to cover it. You can use a drill to do this operation and it's a lot quicker,  but be warned it's very easy to over cook the lapping and make yourself a heap of trouble so here I'm using the old and tried swizzle stick in the photo below

 

You don't want to pile on too much grinding paste to the head of the valve,  to much won't make the job any faster.  The pot of paste in the photo I have  used on various engine rebuilds for last 45 years and it's still half full. Put a little oil on the stem but at all times keep grinding paste away from the stem.  I use a very light compression spring under the head of the valve (arrowed in the photo below)  and put a chalk mark on the edge of the top face, apply light pressure to seat the valve in the seat do a few swizzles ease off, the spring pops the valve up I turn it a quarter turn indexed by the chalk mark and carry on. 

This all takes time put your brain in neutral and listen to radio 2 or dream of your next restoration project or what ever floats your boat but it is well worth the time it takes.

So when do you know that the valve and seat are properly lapped in ? By doing this (photo below)

After some time with the grinding paste the valve seat and the valve head seating face should be pit free and  dull grey .  Clean the seat and valve to remove all traces of paste. Put a series of vertical lines on the valve head seating face as above, this used to be done with a soft lead pencil I now use a Sharpie felt tip. Put the valve back in the guide and give it a couple a couple of swizzles not more that a quarter turn each way then take it out,  it should look like this now (below)

 

The lines have been uniformly cut through all around the seat if they are not then it's back to the lapping in process.

You can also use the distance between the cut lines to measure with vernier calipers (arrowed red above) this measurement will indicate the width of the seating and can be compered to the manufactures specs. 

Do not keep lapping until the valve head seating face is up to the top of the valve head this is particularly important with exhaust valves that need to be thicker at this point.  If too much head material is removed both inlet and exhaust valve  heads will suffer from distortion over time called 'tuliping'  due to the force of the return springs.  Exhaust vales will also be prone to burning at the reduced edge thicknesses.  If the valve heads are worn to this extent then new valves and re-cut or new seats are in the offing I'm afraid.

The seat contact can also be checked using  once again a felt pen, ( it used to be done with engineers marking out fluid)  this time I'm looking for pits or scratches that have not bee ground out.  Put the merest bit of fine grinding paste on the valve head replace then another couple of quarter turn swizzles as before and remove.

Seat marked up 

 

Same seat after a couple of swizzles

 

So that's about it, there's a whole lot of stuff about seat and valve head angles, re-cutting of seats and re facing valves but that is a level of work that is best left to your machine shop and requires proper tooling.

Suffice to say the key measurement for this level of refurbishment is valve stem to guide clearance and condition of the valve and block/head seat.

Pete

 

 

 

Edited February 3, 2022 by Pete Ashby
removal of spare photos

[Pete Ashby]

I thought it timely to venture into the spider and mouse ridden depths of the storage barn to find the radiator,  not seen since it's removal from the truck so a useful job while I source and wait for replacement bearings and piston rings for the engine.

 

On inspection it became clear that at some stage minor repair work had been carried out evidenced by some professional solder work on a couple of tubes and a British radiator firms name plate attached to the header tank. 

 Apart from the minor repairs the core and frame looked to be in very good nick,  proof would be if it held pressure when tested,. While I kept the truck in in extended storage awaiting it's turn in the workshop the antifreeze was well topped up and there had been no evidence of leaks before strip down so hopes were high.  

First off I back flushed the core using a garden hose, this is not a job for the pressure washer, the flow through the tubes was excellent and no rust or sediment washed out all looking positive so far.

So what about testing radiators, you can buy test kits and hand pumps to do this, the price range is vast, from about £25 to well over £150. Cheaper kits have limited bung sizes and will not do for truck radiator inlet/out pipes.  It's a bit like the dial gauge I mentioned in a previous post on the engine work, if your not doing this every day it's not easy to justify the cost of having  kit sat on the self.   Being of tight disposition I have made my own for around £18.00 all up.  This comprises a selection of rubber and silicon bungs (off the internet) and a low pressure gauge.

Just a note here,.... do not attempt to drill rubber or silicon bungs using a drill bit in an electric drill.....bad things will happen and you will end up minus a few fingers.    Having bored many hundreds of bungs in a previous existence I can categorically say a cork borer and some hand soap is the tool to use. Some of the more reckless would freeze the bung in liquid Nitrogen and then drill it, all good fun until the drill bit starts to thaw the surrounding rubber, oh how we used to laugh... those were the days. 

Anyway back to testing radiators this is the home made kit I use.   The pressure gauge is 0 to 15 psi FSD and can also be used to measure fuel pump pressure with some different connections.  The input connection for the foot pump is a valve stem cut out of an old inner tube.

The Canadian military Dodge D series range of trucks are factory fitted with a rather Heath Robinson overflow  tank made from a 1 gallon oil can mounted on the bulk head.  As far as I can see this meant the system was not pressurized as the overflow tank is vented directly to atmosphere,.,

If you try this check your manual on the operating conditions for the radiator under test don't try and blow the thing up like a balloon or it's tears before bedtime. 

I didn't apply very much pressure to the rad only around 2.5 psi the aim here was to see if it held the pressure for an extend period if it did there are no hidden leaks.

That's what's going on here

 

 

Result !! no pressure drop after 30mins so brilliant news and huge step forward.  I can go and chain my wallet up again and after a bit of careful cleaning and a splash of black paint it can be fitted into the frame 

Hurrah 

Pete 

 

Edited April 5, 2022 by Pete Ashby
missed the bit about back flushing out

[Pete Ashby]

Bit more progress on the radiator

Old cruddy paint and flash rust removed from the frame and tanks using a wire wheel.  The top and bottom tanks are brass so a flash coat of etch primer has been applied to the tanks the matrix has been blown through with the air gun at low pressure and will  receive a light coat of black along with the tanks and frame.

 

Coat of well thinned frame black applied by spray gun to the frame and matrix

 

 

Pete

 

 

Edited March 13, 2022 by Pete Ashby

[Pete Ashby]

This is job and knock for another significant step forward in the restoration of the D15. Here's couple of photos of the radiator now installed in the frame.

The block is away at the machinist having the the bores glaze busted and the block manifold face machined as at some point in the engines life the exhaust gaskets have failed and the escaping  gas has etched the block face.

 

 

Pete

Edited March 15, 2022 by Pete Ashby

[Pete Ashby]

Time moves on.

While waiting for major engine components from the US I've  got on with a host of  jobs that take time but don't have wow factors like an a first engine start or first road test. None the less they need to be done.

So first up here's a return to body work on the cab roof, a job that I have been putting off while I thought about the best way to go about it, well that's what I told myself anyway.

While under previous owner ship the left side of the cab roof unfortunately was assaulted by a hefty tree branch during a storm.  This left a  fair sized dent and crease across compound curve of the roof line see first photo below,  the dent is circled and the arrow points in the direction of the crease.

fair

The molding along the front of the cab is a cover strip that goes over the seam weld joining the  windscreen pressing to the cab roof section more about this in a minute.

Here's an inside shot,  the dent and crease are circled,  you can see it's had a fair old bash. Luckily the gutter molding prevented distortion to the door aperture.

First task was to reunite the roof section with the repaired back panel (this work was covered elsewhere in the blog). To prevent the risk of distortion I used a heavy length  of angle iron ( white arrow) drilled and bolted to the windscreen pillar mounting holes (red arrows) the front was then clamped to a couple of wooden support struts adjusted to keep everything level and square.

 

So then it looked like  this

more to follow

Pete

Edited April 22, 2022 by Pete Ashby

[Pete Ashby]

The quick thing here would  be to get a girt big hammer and bash away from the underside bish bash bosh job done.

The problem with this approach I decided was two fold.   First,  a real risk of distorting the whole front corner causing issues with the windscreen and door locations. Second, the roof /windscreen molding seam all along the front of the cab could distort or break apart completely causing a whole new heap of problems.

  Therefore what ever I did need to be slow and controlled so I could gauge the effect the work was having on the rest of the structure. 

What I settled on after a fair bit of head scratching and number of mugs of tea was to use the opposite force to the one that created the damage in the first place all be it a lot more controlled.  Nothing novel here in this approach, body shops use this method in various forms all the time using some very expensive kit which I don't have.

So I made my own out of a stout short piece of angle drilled to take a bolt, various shaped thick washers, and a bar drilled to take a bolt, a fine thread nut and bolt (it needs to be fine to take the force without stripping the threads use a UNF or fine metric) spanners to fit, drill and suitable sized bits.   

 

First off I marked the the crease and its exact direction with chalk in the bottom of the dent then horror of horrors !! drilled a couple of holes into perfectly good steel roof following the direction of the crease.  This photo is taken just after the first and second pull in the front corner .

 

Following the crease line the next set of holes are drilled and the slow process repeated

This is whats going on underneath

 

This is a slow job requiring the crease to be eased up just a bit at a time all along it's length then back to the start and another pass to draw it up a little further. Here it is below after a couple of passes. 

 

On the last pass the steel needs to be drawn just a fraction past the original pressing shape. This enables it to relax back into the correct contour produced at the factory. Here I'm using additional bars to space the pulling bar off the roof line and to spread the force so that I don't create more dents by point loading the roof.

 

And here it is after about an hour of gently working back and forth along the crease the profile has been returned in the  compound curve front corner the crease and dent have been lifted out of the roof and now I'm left with a small area in at the far end of the drill holes that needs a little more work by heat shrinking.  This will put the stress back into it to cure the problem of "paint canning" (area circled in red below) this is a term used when the steel has stretched and lost it's original pressed form, more about that in a later post.

When the whole job is complete the holes will be puddle welded and ground flush. The rather startling yellow paint is some random spray can just to keep the flash rust off the bare metal while I get on with other things.

Job nearly complete with no distortion or damage to the surrounding structure, the power of a brew should never be undervalued !!. 

Pete

 

 

Edited April 22, 2022 by Pete Ashby

[Gordon_M]

That roof seal strip will cause you grief. The least you need to do with it is a thorough clean and seal externally.  If necessary an effective replacement can be made by flattening a section of steel brake pipe.

Having had the whole system apart, that seal strip is a sheet of metal folded in a 'Z' configuration, which is then spot welded to the rear of the cab roof, and then that whole assembly is spot welded to the front of the roof.  

Better avoided unless absolutely essential, about a third of the assembly sport welds on the two I have worked on didn't go through anyway.

[Alex van de Wetering]

Neatly done, Pete!......and very rewarding. I might also use this approach for my Chevy roof when I get to it.......as another benefit is that it doesn't upset the neighbours as much as banging the sheet metal with a hammer.

[Pete Ashby]

4 hours ago, Gordon_M said:

That roof seal strip will cause you grief. The least you need to do with it is a thorough clean and seal externally.  If necessary an effective replacement can be made by flattening a section of steel brake pipe.

Having had the whole system apart, that seal strip is a sheet of metal folded in a 'Z' configuration, which is then spot welded to the rear of the cab roof, and then that whole assembly is spot welded to the front of the roof.  

Better avoided unless absolutely essential, about a third of the assembly sport welds on the two I have worked on didn't go through anyway.

Absolutely right Gordon,  I remember a lot of band width taken up on your forum pages a good few years ago now with regards to the horrors of the cab/screen pressing joint. 

With that in mind that's why I opted for the cautious approach to remove the damage.

regards

Pete

[Pete Ashby]

3 hours ago, Alex van de Wetering said:

Neatly done, Pete!......and very rewarding. I might also use this approach for my Chevy roof when I get to it.......as another benefit is that it doesn't upset the neighbours as much as banging the sheet metal with a hammer.

Thanks Alex the key is make sure you spread the force on the drawing bar. If not instead of drawing out the dent you'll make matters worse by the drawing bar damaging the surrounding metal.

Pete

[Pete Ashby]

Let me say first and foremost that I am not a panel beater those guys are highly skilled professionals,  anything I've picked up is by way of learning on the job so to speak ,......... there is hours of stuff on U tube about heat shrinking, some good some not so good, there are a number of ways to do it this is how I was taught.

Tools required, I gave up my BoC contract for gas some years back and what little I do now I use either this type of heat source or the plumbers type spot torch that gives a hotter more concentrated flame,  various shapes and weights of dollies a couple of different shaped panel hammers, a straight edge and some Blacksmiths chalk compressed air blow gun or a rag and water bucket. 

 

 

Determine where the low spots are and where the area of paint canning is (often called oil canning in the US) then mark it up with the Blacksmiths chalk this won't burn off when heated. 

To shrink the paint canned area I already have a hole in that area but a ding from the pointy end of a panel hammer works just as well. Heat  quickly from underneath until just dull red then cool quickly with either the compressed air or a wet rag.  Now heat again but this time quickly hammer round the hole or ding from underneath with the dollie on top you are not bashing the living daylights out of anything just quick short taps in a circle now cool again. Repeat and after a couple of goes the panel will hold it's shape.

That's what's been going on here

Once the panel holds it's shape the rest of the surface can be worked on here I'm using the straight edge to look for high and low spots across the whole of the pulled area and marking with the Blacksmiths chalk the area and the direction of the crease so that I can tap them out with the panel hammer and dollie this is being done cold no more heat is required now.

This is what it looks like after a bit of hammer work a couple of high spots and some small lows

And here is the finished job a quick flash over the surface with a grit disc in the grinder to knock off any remaining wrinkles and a thin coat of weld through primer ready to have the holes plug welded.  I'll keep the power down low and do a bit at a time using the compressed air gun to cool each area, this is not the time to heat everything up again now it's all shrunk back tight.

Next there's a whole load of fiddly little weld repairs to do around the gutters but that's for another day and more tea will be required while I figure out how to tackle them.

Pete

[67burwood]

That is a great bit of panel work. 👍

[Pete Ashby]

10 hours ago, 67burwood said:

That is a great bit of panel work. 👍

Thanks,  it's a thimble full of experience,  a bit of an understanding about the material your working with and some make do and mend on the kit to make it all happen, mostly it's about not rushing the job.

Oh nearly forgot ,  plenty of tea with chocolate biscuits that's the most important bit.

Pete

Edited April 23, 2022 by Pete Ashby
forgot to add the most important bit

[67burwood]

7 minutes ago, Pete Ashby said:

Oh nearly forgot ,  plenty of tea with chocolate biscuits that's the most important bit.

Very important part of the process  😁

[Pete Ashby]

Taking advantage of the warm spell here in the wild west I've cleaned and painted all the major engine components. These have been sitting around in the workshop leaking oil and grease all winter so it was a case of bite the bullet and get on with it. 

Painting regime after de-greasing ( I use petrol it's still cheaper than the products sold specifically for the job)  is as follows:

Filling the spray gun with gun cleaner everything gets a good going over to remove any last traces of oil and wash off any petrol residue.

Parts are left to flash dry in the sun, next a light coat of etch primer then a good coat of top coat thinned just enough to be able to spray it. 

The top coat I'm using here is an air dry enamel the closest shade I could find to match the original Chrysler factory colour is sold to the tractor restorers for the Ferguson TE20.  It's a pretty close match to the original engine paint on the Dodge engine.  Dodge appear to have had three engine colours during the course of the war,  very early wartime trucks were silver,  the colour I'm using here is a light dove grey (some times I think called smoke white),  late war and factory rebuilt engines used a darker bluer grey shade. 

So a quick visual recap,  this is how it all started an evil oil encrusted lump. 

 

And here are the assorted bits and pieces after a few hours scrubbing and wire wheeling.   The bare block is still at the machine shop so not shown here.

I've turned my attention back to the cab roof but that's going to take some time as there's some very fiddly welding repairs to do around the gutters (drip rails to our transatlantic cousins) and long strip to be let into the rear below the window so that's all for now

Pete

 

Edited May 7, 2022 by Pete Ashby

[Pete Ashby]

Back to the cab roof after a satisfying interlude of spraying nice clean engine components it's was back to chopping out chunks of rusty metal.

There are a number of issues with the roof section that will have to be addressed,  I've already covered the crease and dent removal in a previous post. Now it was the turn of the gutters (drip rails)  in the main these have survived relatively well, God knows how as the construction seems to me to be designed to cause chronic corrosion issues both to the rails and the roof pressing that they attach to.

The first challenge was to determine exactly how the rail pressing was attached to the roof.  After some poking and prodding it turned out the rail (blue arrows below) is spot welded to the lip of the roof pressing (red arrows below) which is not how I initially thought it was constructed.

This photo shows a section of rail removed the roof section cleaned up to bright metal and weld though primer applied.  I used a Dremel with a mini cutting disc attachment to remove the rotten section of rail in stages then ground off the remaining spot welds with a dia grinder

 

Next up was how and in what order to tackle the various sections that need replacing, that's whats happening here marked up in chalk.  I'm still experimenting  how to produce the the curved sections.

Fabricating the straight sections required was not that difficult the casing of an old expired boiler provided exactly the right gauge steel and the correct 90' bend all I had to do was produce the pressing in the bottom of the rail

To make the inverted V pressing I used a large vice,  an improvised press tool made from a short piece of bar, a length of fine diameter steel rod and an off cut of soft wood to back the rail while pressing,  this lets the metal deform into the wood while supporting the rail along it's length and preventing distortion.  

 

Once formed the two edges were trimmed to the required width using a very fine slitting disc with the rail securely clamped.  The repair section was then tack welded into place.

So now it looks like this when the roof is removed from the rear cab section it will be turned upside down I'll grind all the tack welds flush.

 

There is no evidence that any seam sealer was factory applied to the drip rail/cab roof joint as is the case with civilian cars of the period.  After the effort that it's going to take to repair these I think I want to seal the joint so I'm currently exploring options for a seam sealer that will take paint and not crack after a year or two....... suggestions welcome.

Pete

 

 

[64EK26]

Hi

I have used MHP PU Adhesive Seam Sealer on many occasions and it is really good as it is an adhesive non shrinkable sealer (also made by U-POL as Tiger Seal). These are polyurethane based, do not uses a silicone based one as you will not be able to paint over it.

To get good smooth edges I use a brush/cloth dipped cellulose thinners to smooth and clean up excess. By the way it sticks to anything.

Cheers

Richard

 

[Pete Ashby]

On 5/14/2022 at 7:44 PM, 64EK26 said:

Hi

I have used MHP PU Adhesive Seam Sealer on many occasions and it is really good as it is an adhesive non shrinkable sealer (also made by U-POL as Tiger Seal). These are polyurethane based, do not uses a silicone based one as you will not be able to paint over it.

To get good smooth edges I use a brush/cloth dipped cellulose thinners to smooth and clean up excess. By the way it sticks to anything.

Cheers

Richard

 

Thank you Richard very useful information. 

I assume it would take an undercoat then a finish top coat of paint?  Any idea how that would turn out using a semi matt top coat finish? what I'm trying to avoid is a shinny gloss streak in the drip rail.

Regards

Pete