Pete Ashby

Last job for the camshaft installation is to measure the end float of shaft (gap between the thrust plate and the front bearing on the cam shaft) after the thrust plate is securely bolted in place on the front of the block. I prefer to do this before the valves and springs are fitted. If you chose to do this when the the valves are in place all the adjusters must be backed completely off to remove any valve spring force on the cam followers and the oil pump or distributor must not be fitted if it's cam gear driven, the cam shaft needs to float free in the supporting bearings to make the measurement. There are two ways to take the measurement both are perfectly fine. Quickest easiest and cheapest is to use a set of feeler gauges which everyone will have in their tool kit. The second that takes just a bit more time to set up and arguably is more accurate is to use a dial gauge. This photo shows the set up the measure the end float using both methods Red arrows, thrust plate bolts and thrust plate Blue arrow, end of the camshaft with the drive gear hub in place and the end of the dial gauge resting on the end of the shaft. Green arrow, here using the feeler gauge method to gauge the gap between the plate and the end of the cam shaft To take the measurement push the cam shaft as far back against the thrust plate as possible by hand.....do not just give it a quick tap with a hammer !. Now using a small pri bar or large flat blade screwdriver inserted between the thrust plate and the drive hub gently apply force to move the cam shaft forward..... your not trying to open a tin of paint here. Take the measurement and repeat three times they should all be about the same give or take a fraction then divide by three to get the average. Below the dial gauge mounted on a magnetic base stand. Using the feeler gauge I had 8 thou (0.008") end float, using the dial gauge (which is metric) I got 0.185mm this equates to 7 thou (0.0073"). Manufacturing tolerance and maximum permissible end float due to operational ware are in the manufacturers spec for the particular engine being worked on. Rule of thumb for a 6 cylinder side valve camshaft the maximum permissible end float is around 10 thou (0.010 ") with an operational tolerance of 2 to 6 thou ( 0.002" to 0.006" ) I'm just a tad outside this but inside having to fit another thrust plate. Why is all this important ? Well the camshaft will try to wind itself backwards and forwards out of the block due to the forces from the valve springs which are applied to the cam lobes transmitted to via the cam followers. Also by the timing chain being dragged round at the front end by the crankshaft gear that drives the camshaft gear. The effect of excessive end float leads to ware of cam shaft lobes, lateral tooth ware on the gear that drives either the oil pump or distributor depending on your type of engine design and in extreme cases it will mess up the timing chain and sprocket gears in short bad news all round. Having said all that there has to be some free movement hence the operational tolerance of 0.002 to 0.006 thou to take account of thermal expansion of the shaft or else it would start to bind as everything warms up. Bit wordy this post sorry, but it's something that can be over looked and and it's important to the overall operation of the engine. I like to think of the cam shaft as the bit that joins all the other twirly bits in the engine together to do the right thing at the right time. Pete

As the block is sitting in the workshop all clean and shiny it seemed like a good idea to get some of the internal fittings out of the various tins, boxes and bags and get them bolted back into it. Those who are accomplished engine builders may want to skip through the next few posts as I'm going to continue in a similar vain to previous posts covering strip down. There will be a few detailed photos and supporting text which may be of interest to those who haven't yet tackled this sort of job. Although this is a six cylinder engine all side valve engines are of a similar construction with only minor differences so the process is relevant no matter how many cylinders you have. Without further a do here's the first installment of the rebuild. What I'm trying to show here is using an endoscope to check that the oil passage ways are clean and clear of swarf, you can just about see the passageway in the top center of the screen, it's a lot clearer on the instrument screen. This gizmo is not a huge sum of money off e bay and well worth the investment. It takes the guess work out of this sort of job and can also be used in all sorts of situations including looking for blocked household drains !! Now that everything is clean the key is to keep it that way, the last thing you need is grit getting into the internals, so keep the block covered at all times with a cloth when not actually working on it. I would recommend this stuff, off the web or your local motor factor, there are several different makes but they all do the same thing. It's a very viscous oil base full of good things like Zinc, Molybdenum and a few other additives that will stick for extended periods to running surfaces and bearings and protect them in the vital seconds before oil starts to circulate on that first start up....... nobody wants a dry start. So in this episode I'm fitting the cam followers and can shaft into the block. Photo of a side valve cam follower with the adjustable tappet block fitted just waiting for a dose of assembly lube to be applied. This is how they have been stored on a card, numbered 1 to 12. Number 1 at the front of the engine this ensures they go back in the same position that they came from. You can see I'm working back from the rear of the engine here. No real reason either way is good, I've already fitted 8 followers into the block. Followers and guides have been measured using similar techniques as described in my previous posts on measuring things. Everything was found to be well within factory spec so good to bash on. The block needs to be upside down or on it's side for this next bit. I have the block mounted on a rotating engine stand it makes the job immeasurably easier and keeps everything off the deck and out of the dust and muck. I'm too old to be bent double on the floor or wrestling the block on a bench, been there, done it many times, got the bad knees and back to prove it. And here are all the followers in position in the block each one has had a dose of assembly lube prior to fitting you don't need gallons of the stuff there is more than enough in the bottle to do the whole engine. OK next up is the cam shaft this has been stored vertically wrapped in oily rags. In the photo below it's been washed in petrol and the machined surfaces rubbed over with a piece of fine grade Scotch Brite to remove any residual tarnish. Don't use emery or carborundum paper, it will damage the machine faces and possibly leave embed fine particles of grit in the machine surfaces.....bad news. The rear of the cam shaft is on the left of the photo and the front with the thrust plate and drive gear hub fitted to the right. the gear teeth in the middle of the shaft is the drive for the oil pump which has a slot in the top of it to drive the distributor so a pretty important bit of kit in any engine. Bearing faces and have been measured against the factory specs, and the cam lobes (that's the pointy bits) have been checked for ware and or failure of the case hardened surfaces and found to good to go. Like wise the white metal bearings that carry the cam shaft in the block have been measured and checked and found to be well within spec and undamaged. All the cam machined surfaces have had a dollop of lube along with the bearings in the block. The cam shaft is very carefully fed through the bearings in the block. Two points to note here, first the edges of the cam lobes can be sharp so look out for your fingers, second and following on from the first point the sharp edges of the cam lobes will dig into the soft white metal bearings in the block if care is not exercised feeding them thorough......more bad news and negative vibes if this happens. Here it is installed, now the cam followers can't drop out, as they are sitting on the cam lobes so the block can be turned up the right way. And here's a view into the valve chest with the cam followers and tappet blocks in view all sitting on the installed cam shaft. That'll do for now, more to follow tomorrow. Pete Just a reminder it's your best friend here for this job.

Towards the end of last week I got a call from the machine shop to say the block was ready for collection, Hurrah!! Once home I flushed the water jacket with a pressure hose and compressed air gun poked inside the block cavities to stir things up a bit. Surprisingly there was not a huge amount of rust coming out what little sediment there was, less than tea cup full, appeared more like mud.. I poked the endoscope into various orifices, in the block just to be clear, and everything looks pretty good once everything had been dried off in the sun. Next having blocked off all holes with bungs or plugs and with a sheet of hard board fixed to the block face and sump the old paint was removed from the outside of the block with various rotary wire wheels and brushes. Now it was the turn of the oil ways to be thoroughly flushed through starting with the oil pump feed , main gallery, main bearing drilling and lastly valve chest and guides in that order and in both directions using first paraffin then blown out at high pressure with the air gun. This is a vital part of any engine rebuild as machining swarf must be removed, if not it will wreck a newly rebuilt engine in minutes. All surfaces were then washed off using the spray gun filled with gun cleaner to remove residual grease and oil A light coat of clean automatic transmission oil was applied using a small brush to all the machined surfaces to prevent flash rust forming. With the machined surfaces recovered the block sides and ends were given one coat of etch primer, then top coat as per the previous blog entry on engine components. From this And now it looks like this Here's the valve chest side with one new exhaust valve test fitted to make sure it's the correct one for the job, it will be removed before the cam followers and cam shaft are fitted. Pete

Indeed as well you know !, it can some times feel like trying to knit fog

As a bit of a break from drip rail manufacture I've started to repair the bottom rear section of the roof. On Canadian military D series trucks the cab roof can be removed. I assume this was an aid to shipping, it was probably a good idea 80 years ago but now it's an absolute nightmare with regard to corrosion. The joint between the roof section and the back of the cab is covered by a strip of 18 gauge steel that is spot welded to the cab roof section to form a flange. You can see it here, cab roof section and cab back (red arrows), with the aforementioned strip shown (green arrows). The whole thing then bolts through the bottom cab section and is held together by machine screws and nuts. Those of you who are are heroically still following this blog might recall I replaced the internal matching to this strip when I covered the cab back restoration. First off I removed the spot welds and took the external cover strip off leaving two short sections at either side of the cab door, fortunately there is virtually no corrosion there. These short sections (red arrows below) will be butt welded to the new strip and will form a datum point to work to and from. This now reveled the extent of the corrosion to the bottom of the roof section (blue arrows below) Nothing for it but out with the fine slitting disc and take the whole bottom section off to a point where there was some good metal to weld to. This is the result, ideally I'd have liked to hide the new piece behind the cover strip but his was just not an option due to the level of corrosion present. Here's the new repair section butt welded into place a slow job to keep heat distortion to a minimum. the steel has been wire wheeled back to bright, then a thin coat of weld through primer applied, that's the silver paint here. And here it is with the top knocked off the weld and the usual hideous yellow spray paint used to give me a guide so I don't grind too much off the original roof or the new replacement section. When the roof is removed the weld line will require plenishing to remove the shrinkage and then final dressing with a range of grinding tools. Then the cover strip can be added using the old one as a guide for the fixing screw holes. Oh such fun !!, then it will be time to sort out the rear window. Pete

Continuing work on the drip rails one of the challenges is to reproduce the curved sections of the drip rail. I experimented with several ideas none of which were particularity successful so I decided to produce the replacement sections that I needed as a two component item. A curved base section then a shaped vertical section to match the required curve that could be welded onto the base. First photo is the part completed curved repair section. The base (blue arrow) is cut slightly wider than required, with a small turn up edge is hammered up at 90' before the curve is formed (green arrow) this is then ground and filed back to be around 3mm deep. The purpose of the turn up is so that when the finished piece is attached to the cab roof there is something for the weld to bite into rather than just the flat gutter section. Keeping the turn up as small as possible will let the base curve to be formed without distortion, it also helps to prevent the curve distorting during the welding operations. The card board pattern at the top of the photo gives the required curve this was taken before the old rail section was removed from the cab roof. The steel base section is thin enough to shape by hand and or use a light hammer on a former. The vertical section (red arrow) is cut extra wide at this stage, it's easier cut and shape the required curve to match the base section if left over long and helps prevents distortion during welding. Everything is cleaned up then the vertical section is butt welded using gas Mig onto the base. The steel I working with here is 18 gauge so it will weld at low power with a fairly low wire speed, even so it's a case of join the dots to keep the heat out of the work. The weld is then ground and filed to fit the curve and trimmed down to the required height. A slight rounded profile is sanded on the outside bottom edge to reproduce the original which of course was folded from one piece of steel. It ends up looking like this, the ends will be trimmed to match the remaining section of drip rail it will attach to. This is where this particular section is going at the top rear of the driver's door I'm sure there are other and better ways of doing this job as it's pretty labour intensive but this seems to work for me. All I have to do make another four curved sections and two straight ones and that will be the drip rails restored. Pete

I've just looked this stuff up and it's cheap enough to get some and run some tests with it I'll post the results on how it takes semi matt paint here in the blog thanks again Richard for your input Pete

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

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

Google your local engine reconditioning machine shops they all should be able to carry out this work is all standard stuff for them I would imagine you will find a number in the Black country area Pete

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

Ignore that last post of mine, I've just re read your comments, it looks very much for what ever reason the activating rod is not long enough, for some bizarre reason somebody hasn't chopped a portion of the adjustment thread off have they? Pete

I may have misunderstood the problem here but is it that the lever physically wont engage/disengage depending on adjustment or, is it that the lever operates but the transfer gear won't engage/disengage ? I'm just wondering if you have front axle wind up as I assume you are not moving very far if at all? Pete

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

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

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

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

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

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

I have to say I've not come across that set up on a military truck before so in that case I'd look for an induction leak first off, A couple of other quick checks: correct float height adjustment and how is the fuel delivered is it a gravity system or pump ? if it's a pump then check the delivery pressure. Interesting to know the outcome, good luck. Pete

Just a thought, I'm guessing your carburetor has some form of governor fitted ? Pete

Could well be, the engine should respond without the filter in place, have you put a vacuum gauge on and run some tests ? It will be able to show up induction leaks, valve problems and ignition timing issues as well well worth doing if you haven't already coupled one up. Pete

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

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

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