Jump to content

Pete Ashby

Members
  • Posts

    1,681
  • Joined

  • Last visited

  • Days Won

    8

Everything posted by Pete Ashby

  1. Piston rings come in nearly as many different shapes and combinations and materials as there are stars in the sky. So you must know what type you are working with because it makes a difference to the clearance tolerance and how they are fitted to the piston, get a good book or go on the web and check your type specific manual. The rings I'm working with are very basic square shoulder iron 1st and 2nd compression rings with a compounded oil scraper pack made up of a top and bottom rail with intermediate support spacer spring . The photo below shows the full set for one 3 ring piston, the number sequence 1 to 7 are in the order that the rings are fitted to the piston starting at the lowest ring groove and working upwards to the crown. They are as follows: 1 backing spring for oil scraper pack 2 bottom oil scraper rail 3 spacer support spring 4 top oil scraper rail 5 backing spring for 2nd compression ring 6 2nd compression ring 7 1st (top) compression ring I'll mention the tool in the photo in the next post, for now this is all about preparing the rings Tools for the job, self explanatory apart from the black strip this is 600 wet and dry paper and maybe the little gizmo on the extreme right this is a rotary ring file, Here's a closer view of it below it's a hand powered grinding wheel more about this in a minute. For the traditionalists out there this is the bit of kit that the rotary file replaced All the above kit is for setting the appropriate end gap on a piston ring. In the first photo in the thread you can see the rings all have large gaps but when inserted in the bore the gap will close up to the point where the ends could butt up tight and jam the ring (and therefore the piston) in the bore all sorts of bad karma follows this event. All this means the ring has to have a specific gap when fitted into the bore. The size of the gap is a collective function of bore diameter, piston material and construction and the material and type of ring used. There are rule of thumb measurements like the set in tables below from my 1938 copy of Practical Automobile Engineering, but the spec for the particular engine being worked on should be checked and also any information that comes from the manufactures of the rings. And just because it make me smile here's the inside cover photo from the same book....Hmm I could just see myself in that beret and a set of brown overalls. Where was I ? ring gaps OK here we go then On a rebuilt engine each set of rings will be gaped and fitted to a unique bore this is because there will be minor deviations in bore measurements between the various cylinders. First put a small fine smear of assembly lube around the bore. Take a compression ring and seat it into the top of the bore as per photo below. Place the open ends of the ring in first, hold it in place and feed the back in with your thumbs it a bit of an acquired skill.. Rings are brittle and easily broken if handled incorrectly so practice on one of the old rings you took off at disassembly. See how the gap has closed up red arrow the blue arrow show a reference mark I have put on the ring with the sharpie pen more about that in a minute. If the ends butt up at this stage don't keep pushing the ring into the bore you'll have to file some off I'll cover that in a minute, but we'll assume here there is still a gap Take a piston and rod without rings fitted and gently push the ring down the bore about 1 inch that's what's happening here this action squares the ring in the bore, remove the piston and rod. Now measure the gap using a set of feeler gauges see photo below and compare with the spec. I'm measuring both at near TDC and BDC ring positions on this engine as it has not been re-bored. I know there is some very slight taper and ovality in the bores so the ring gap could be good towards the top of the bore but butt lower down, on a re-bored engine this second measurement would not be required. Using the ring file, a spot of oil on the wheel shaft and screw it firmly to the bench or lump of wood so that the handle can turn freely. mark one edge of the upper face of the ring with a dot using the sharpie pen (the blue arrow from the fitting the ring to the bore photo above ) this will now act as your reference mark. I was taught to only file one end of the ring so the datum mark should always face up and be the edge to file against. Place the ring on the file bed and butt the ring against the pegs to keep the end of the ring square to the grinding wheel. The grinding wheel must only cut in a downward motion otherwise the ring will jump up and flutter and /or chip at the edge. Only very light pressure is required to hold the ring against the wheel, place your fingers on the ring as shown below. Give the handle four or five turns then take the ring off the file bed, use the 600 wet and dry to very lightly take off any burs formed on the end of the ring do not round off any of the edges of the ring Repeat the process of fitting the ring into the bore centering and taking the gap measurement you will need to repeat this operation a number of times to get the required result. The file removes a lot of material very quickly so patience is the key, you can always take some more off but you can't put it back on if you overshoot and too bigger gap is as bad a too little On a two compression ring six cylinder engine this operation may well take 2 or 3 hours to do the six cylinders. The good news is that oil rings rarely need gaping but each rail and spring support should be placed in the bore and the gap measured just to be sure. Pete
  2. Next step is to assemble the pistons to the rods. The pistons have been washed in gun cleaner and the ring grooves cleaned with a narrow strip of lint free rag then inspected for damage and all found to be good to go. The rod piston pin, (little end or gudgeon pin) all different names for same thing have previously been measured and inspected and found to be good to go again. If not new bushes would be required and these would have to be reamed to match the pins a job best given to your machine shop as clearances need to be very precise. A quick rub over with Auto Solve metal polish to remove the oil tarnish and a polish up with the lint free rag . The point about using lint free rags is this, bits fluff or threads shed during any stage of the engine build may ball up blocking the finer oil ways, some people use blue workshop paper towel this comes in a big role, I'm just too tight to buy it. The method for fitting the piston to the connecting rod will vary depending on the design, materiel and make of the piston, variations on a theme here. Some include heating the piston in boiling water or hot oil and /or freezing the piston pin. Not required here the pins are fully floating and a push fit at room temperature. ( unlike a jeep pin for example that is clamped on to the piston with a lock bolt). People have contacted me and said they like seeing the tools used for various jobs so tools for this job, are shown below. On these pistons the pin is held in place by circlips (spring clips C clips) Below are two types of pliers for removing/replacing clips, on the left the traditional type working like conventional pliers. On the right a screw thread version with various jaw fittings for internal and external clips, it saves having to hang onto the thing all the time both have strengths and weakness, I find the the screw thread ones much better for bigger clips on bearing housings for example. Photo below shows the parts for cylinder No2 , note the front of the engine is marked on the piston crown with an arrow ( during disassembly) and the pin is coming out of a numbered bag to ensure it goes back into the matching rod numbered for the bore ( stamp mark 2 on the bearing housing shoulder ). The rod cap bolt threads are protected with a couple of short lengths of polythene pipe pushed onto them. It is vital that the correct rod and piston goes into the correct bore and that the rod is assembled to the piston the correct way round. This is why on disassembly you must know which direction the front of the engine is relative to the piston crown likewise which orientation the rod is relative to the piston. Get this wrong and a whole bag full of woes will follow in very short order leading to total engine failure, assuming you can even get the thing assembled in the first place Observation and the technical manual for the engine being worked on are critical here. You really can't guess, having said that jeeps owners will be aware that the war time TM manuals had a misprint with regard to rod/piston orientation that was not corrected for some considerable time. On this particular engine type with the piston orientation facing forward in the block the stamped rod number and oil squirt hole face the camshaft side. To make sure I don't get confused I have replicated the front of the piston mark( photo below) with a sharpie pen on the piston wall so I can see it with the piston upside down. First I use a small amount of the engine build lube (mentioned in a previous post) on the surfaces. The pin is started into the piston just enough so that the rod can be fed on. Supporting the rod the pin is pushed carefully all the way through to the other side, check everything is free to move without binding and fit the clips ensuring that they are correctly seated in the locating grooves. And if it all goes well it ends up looking like this. Pete .
  3. My son David was there on the Saturday. He reported almost exactly the same impressions, nice to hear some positive event news, a change from the horror show that W&P became. Pete
  4. Interesting, never come across this before. Am I right in thinking that the strip acts like a long washer spreading the force applied by the bolts more evenly along the sump flange ? Pete
  5. Firstly Pierre you most certainly are not hijacking the blog. It's exactly what I would like to achieve, hopefully stimulating discussion and dissemination of ideas and techniques relevant to our vehicles. I would very much encourage others to join the discussion and to add their own relevant ideas and knowledge. I am continually at pains to point my professional background is not in motor engineering but I have been lucky to have known and worked with a few who were trained in the discipline. Also I've been restoring both for my self and other people a reasonable cross section of WW2 vehicles for the last 50 years. This doesn't make me an authority on the subject by any means there is always something new to learn with MV's. So after all that guff to address your points above from my own perspective: 1. Some mechanics recommend to soak cork gaskets in water before fitting as they can dry out if stored for sometime? Yes they do and some will do it in boiling water too. The idea behind this is that the cork dries out, shrinks and becomes brittle over time, the water softens and expands the cork to a degree. I've never had much success with this particularity with complicated shapes where a number of bolt holes need to line up correctly. It's the major reason that drove me to start making my own gaskets. That and it's a lot cheaper frankly than tracking down and buying something that has had a dubious storage life for the past 75 to 80 years and is structurally modified by time even if it has been stored correctly. 2. Apply sealant to both sides of the cork sump gaskets or just the pan side so removal is a lot easier? This begs the question if you only apply the sealant to one side which side do you seal ? The block face is the machined surface so should in theory provide the best surface for the cork to seal on, mostly true but not always is how I would answer that. I seal both sides just to be sure and that's why I use something like Blue Hylomar (see previous comments above) Back in the day everything got a good dollop of Red Hermatite and required a hammer and chisel to free the part on disassembly. I have heard of people greasing one mating surface when using Hermatite but it always seemed a bit counter intuitive to me. It's not good practice to reuse a gasket it's a consumable at the end of the day. Here the issue is to use something that gives you a fighting chance of removing the part in the future. Today there are reasonable choices in the market for non hardening sealants and if you make your own gasket after the initial cost of buying the cork sheet it's just your time (that one I made took about 20mins) to knock up a new one that is fresh and fits properly where it should. Pete
  6. Hello Pierre, I'm pleased you are enjoying the Blog content. As for sealants it's a very wide ranging subject these days that's worthy of a blog all of it's own. The short answer is I regard the choice of sealant similar to the choice of which tool to use ie the right one for the right job. Having said that there are times when a comprise has to be made in terms of whats available for example an emergency repair by the side of the road as a get you home fix, for that I don't think you can beat a great big tube of RTV silicone the bigger the better. For this job however I don't think silicone is the best choice for making a nice job on a cork gasket I would ague why use the cork just cut a card gasket and plug it up with RTV, but there are other issues to do with clearance values that will prevent the use of a thinner gasket of course . The Permatex No3 Aviation is a good one as it is applied with a small paint brush so you can get a decent covering on all surfaces it's non hardening and resits virtually everything.. In the mists of time here in the UK choice was limited to either a form of shellac basically a varnish or good old Red Hematite which I have to say I still find has it's uses. Blue Hylomar is a form of non hardening polyester urethane sealant good to 500'c Ok for oils fuels and water. It's very good with card and paper gaskets but like all tube sealants can be a bit messy to apply uniformly, none the less it's my go to sealant of choice. Just a point about your Bedford sump I suspect it's not dissimilar to the GM Chev 216 sumps that I'm familiar with and the sealing surface is not particularly generous. If the pan fixing bolts have been over tightened in the past it raises the profile around the holes in the pan and makes getting a decent seal difficult if they are not dressed back flat with a body hammer and dolly before fitting. The other weak spot on all sumps is the front and back seals these need to be kept long by about 1/4" each side so they compress and seal around the front and rear main caps properly when the pan is fully tightened down, a bead of RTV on these may not go amiss as a belt and braces exercise. Pete
  7. Back to the engine as parts slowly start arriving from various sources from UK, Europe, US and Canada, it's a slow process and the freight costs these days are crippling even though the parts themselves are reasonably priced. Anyway enough moaning what's be occurring ? Cork gasket making that's the topic for this post. In a previous post on overhauling the gearbox I did a bit on how to cut paper gaskets so I thought I'd complete the theme by looking at cork ones too. Cork gaskets are used where there's a lot of oil sloshing around, so sump gaskets and valve chest gaskets are often made from cork but they crop up in all sorts of other applications as well . Trying to use 80 year old cork gaskets frankly is at best a lottery and more often than not a complete waste of time and money so I don't, I make my own. This is how I do it, there are other ways so again if you've done this a few times I'd skip this section or just look at the photos.. Here I'm using 6mm cork sheet various thicknesses can be obtained from gasket material suppliers find them on the web. Take one sump Collect the tools for the job, all self explanatory with the perhaps the exception of the wad punches (next to the hammer) these come in sets from about a 1/16" up to about 1" diameter for not a lot of money. You use the appropriate sized punch to make the holes for the bolts they can be used on card and paper as well a bit more about how to use them in a minute. Here I've cut a piece off the sheet over size in both length and width I'll explain why in minute. I've marked three holes with the sharpie pen and punched them out with the Wad punch and a hammer. I'm using a couple of sump bolts and some nuts just done up finger tight to hold everything in place this will now act a datum point and the other holes can now be marked out. To make the holes, place the cork on a piece of soft wood ( don't knock through onto a hard surface you'll ruin the punch, place the wood on a solid surface, I'm using a small anvil. but a bench, or floor is just as good. With one strike knock the punch through. You don't need to knock it into next week, however don't just keep tapping at it as it will go of center and make a ragged hole. Fit all the bolts and make sure everything lines up use the Sharpie to mark out the edges then remove the cork blank and it looks like this. The reason for having spare material up to this point is two fold. Firstly it lets you move things around a bit as you line up and mark out the holes. Secondly the spare material supports the gasket shape during punching and cutting out and prevents creep and /or distortion of the finished gasket. Now trim up the outer and inner edges I'm using straight cut metal shears here which cut thick cork really well as well as scissors and a craft knife along with some 120 grit paper to smooth off the edges and profiles. Cork tends to grip a craft knife blade some force is required so always cut away from yourself and keep your fingers behind the blade......... stating the bleeding obvious here Pete........ Quite so !! Anyway after raiding the the workshop first aid box it ends up looking like this, I've marked on the gaskets which way up they go fairly obvious on these but not always the case and this saves time and angst later. And here they are in place and I've cut the front and back seals as well. I've put the bolts in the wrong way round for now with a few nuts finger tight to keep the gaskets flat and out of harms way until everything is ready for fitting. Pete
  8. Knock Knock, hello Matt are there ?? are you still interested in the manual if you are see my reply to you above I'll need some information to work out the postage for you. regards Pete
  9. Good morning Matt yes it's still for sale congratulations on your truck good choice can you let me have the following by private message please full postal Address inc post code Contact tel number and email I need these for the courier forms. I'll fill in the information and get an all up price for you inc postage at cost, p&p no charge, . then I'll come back to you on HMVF by PM and let you know the all up cost. Payment please by Paypal to peteashby@hotmail.com. When I get payment I'll book the shipment and let you have the courier and tracking details OK ? Regards Pete
  10. Your right about welding thicker steel, gives the opportunity to get some decent penetration without the risk of burn through Good job ! Pete
  11. SOLD Dated August 1943 with 138 pages of detailed text and diagrams. The manual covers both the GS and ambulance version. Condition Fair no torn or loose pages, spin and staples are good, front cover shows signs of ware but otherwise the pages are unmarked see photos. £25.00 by paypal plus p&p at cost ask for quote will post world wide. Pete
  12. Bedford mechanics hand book published by Vauxhall Motors Sep 1941, second edition, this is an original document not a copy. See attached photos, a 207 page booklet containing text and diagrams covering all aspects of mechanical work and operation for Bedford MW, OX, OY and QL trucks. Condition fair to good, some damage to lower left hand edge of front cover, no loose, torn or stained pages, spine is good £30.00 plus p&p at cost will post world wide SOLD Pete
  13. Drivers hand book for Bedford OY dated Dec 1941 See attached photos, a 52 page booklet containing text and diagrams this is an original document not a copy. Condition excellent, virtually unread, no loose, torn or stained pages, spine and staples perfect, it's very rare to find a drivers hand book in this condition, £40.00 plus p&p at cost will post world wide Pete
  14. SOLD See attached photos, a 72 page booklet containing text and diagrams this is an original document not a copy. Condition very good to excellent, no loose or torn or stained pages, spine and staples in perfect condition, it has a June 1940 dated addendum attached to inside cover. There are two ministry ink stamps on the front cover and one on the inside fly leaf see photos. £45.00 plus p&p at cost will post world wide Pete.
  15. SOLD Drivers hand book for Dodge 3 ton 4x2 issued Aug 1943 under supply Mech contract 2916 Located UK, Condition: Good to very good, no lost or torn pages, all staples in place, slight stain on top right front cover clean on internal pages. Top right hand corner of pages slightly turned in see photo £30.00 by paypal will post world wide ask for quote at cost.
  16. Thanks, just this small repair took all one afternoon, cutting out the rusted parts, prepping the remaining metal for welding, producing a card board template and adjusting it to fit the contours of the roof section and drip rail, cutting and shaping the steel, welding it all in place then grinding and sanding back. That's where the time goes on restoration projects . It's perfectly possible to put a top coat on an entire vehicle in the same time frame with dramatic transformational results where an afternoon spent fiddling about with this repair will be completely invisible in the scheme of things but at least I'll know it's not full of filler. Pete
  17. What better way to spend a wet and misty day in the wild west than chopping out rust, the saga of the drip rails is now finished so a few photos to show the progress In the last update on this work I showed the right hand side rail at the rear of the door aperture cut out and the replacement fabricated section ready to go in. Here's the completed job on the right hand side Next up was the left hand side not requiring quite so much work but what needed replacing was a bit tricky to fabricate and weld in place This is the front of the left hand door aperture rail and a small section of the front roof removed These are the two replacement sections folded up ready for welding And here's the finished job there will need to be a bit more work after the media blasting. Pete
  18. For MB and GPW jeeps main bearing and big end bearing complete engine set new unopened condition. £80.00 to clear this includes both mains and big ends complete engine set plus p&p at cost (ask for quote ) Thanks Pete
  19. Here you go this should provide some useful information if follow the link below http://jeepdraw.com/Trailer_Canadian.html Pete
  20. I have one of these waiting it's turn in the workshop, mine has had a steel and angle iron body fabricated onto it at some stage. Somewhere I think I may have some factory photos of the correct body, from memory there was an early wooden version and a later steel version I'll see what I can dig up over the next couple of days for you and post here. Pete
  21. If it encourages just one person to have a go then I think it's worth the band width. Without the help and encouragement that I have received over the years I wouldn't be able to tackle these sorts of jobs. With regard to the tooling it would be disingenuous to suggest that everything can be done with an adjustable spanner and a claw hammer. But a basic tool kit including a set of combination ring and open end spanners, various screw drivers, set of sockets, a few basic measuring instruments and a little know how and application will get you a long way along the road to a successful engine or gearbox rebuild. Pete
  22. The previous preamble was unnecessary for many I suspect,l but hopefully useful to a few, this post is about actually getting the thing installed in the block. Valve springs often have one end where the coils are more tightly wound than the other end, these are known as progressive springs it's all to do with harmonics and limiting stress caused by momentum in the spring, valve bounce in it's simplest form. If you are that way minded and want to know more google "why does a valve springs have a different number of coils at either end" there's loads of detailed info out there from the basic to the PHD level physics of spring design and operation. If you don't need to know why all you need to know is the end with the closest wound coils goes nearest the valve head so for side valves it's up and for overhead valves it's down...... Simples..... as that little fury critter is apt to say. Having said that the springs in this engine are not progressive wound I checked and double checked even measuring the coil gaps with a vernier caliper to be sure so they will go back in exactly as they out. So to the task in hand: Take the correct spring for the correct position in the correct orientation ensure the tappet adjuster is screwed fully down and the cam follower is on the Heel ( lowest portion) of the cam. Fit the spring retainer and wiggle them both into position under the guide and above the tappet adjuster, this can be a bit of a fiddle on some engines. Do not resort to levering the spring into position with a screwdriver you'll damage the spring and possibly lose an eye when it flies out and smacks you in the face apart from possibly deforming and or cracking the spring. Take the corresponding valve and add a smear of assembly lube to the stem portion that that runs in the guide (that's the shinny bit about an inch or so below the head of the valve) keep it off the section that sits in the port orifice or else you won't be able to see across the workshop when you do your first start up. Put the merest smear of lube on the on the valve seat if you don't intend to start the engine soon after rebuild. Insert the valve in the guide (don't just drop it in you may damage the ground sealing surfaces on the seat and or valve that you spent hours lapping in). Carefully feed in the stem holding the valve by the head . Hold it just off the seat and ensure it will slide up and down the guide with out binding, slight turn left and right as you do this will move the lube around the guide and stem surface. Take the valve spring compressor, compress the spring making sure the valve stem feeds through the spring retainer plate and appears out the bottom, keep compressing the spring until the collet grooves are visible. Do not keep winding the compressor up until the spring is jammed tight fully closed and you can't get another once out of the compressor, this could crack or damage the spring on smaller engines, just enough is good enough here. Note: If this task is being done with the sump on make sure all holes back into the block are closed off with rags, it's a dead cert that at least one collet will drop out and go strait down into the sump, ask me how I know ?....... Oh, how we laughed after a very long day in a heatwave back in the day. This next bit can be fiddly on side valve motors, over head versions are easier as you can see what you're doing and gravity is not working against you....... Eh? ......have a look at the photo below. I have one collet in position, narrow end up remember, (red arrow right ) the second one is going in with tweezers (red arrow left ) turning the block on it's side can help a bit. This is not a job to do after a bad day at the office, row with your partner/cat/dog/neighbor whatever. It will try the patience after one or other or both collets drop out for the umpteenth time and your only on cylinder No2. Some of the angst can be alleviated by applying a small amount of thick grease to the internal surface of the collet so it sticks to the stem, assembly lube works quite well too but everything gets a bit slippery after a bit. . Photo below, both collets in (red arrow) and correctly seated in the stem grooves Now slowly release the compressor it doesn't hurt to just pinch the collets between finger and thumb while doing this to ensure they seat in the retainer and don't get knocked out of the stem grooves as the spring pressure takes hold of them. It should now look like the photo below, notice here the collets are now fully up into the base of spring retainer, on some designs there will be just a small shoulder showing the bottom of the retainer the key is make sure they are properly seated and locked by the spring retainer plate. And that's it really, take your time keep everything clean and grit free and the jobs a doddle... most of the time. Just for completeness a photo of an inlet valve from this engine with the standard type of spring retainer that will be found in many other engine types. Finally to prove I wasn't having a dig at my Ford V8 owning friends and associates here's a diagram for a Ford flat head V8 valve pack ( blagged off the web sorry no credits) very different set up as you can see Setting the lash ( tappet or valve clearance gap) is a black art involving a bench grinder, three maidens at midnight and a cockerel,..... well maybe not the cockerel........, enough to say it is very different process. The whole assembly is inserted into the block with a tool that looks like it would be more at home poking the fire, Mr H Ford always did things his way. And here's a flat head Ford valve and spring pack I keep it to remind myself why I don't have any V8 Fords whenever I feel like straying to the dark side, That's it for this section next up will be crankshaft, pistons and rings but I'm still sourcing parts so that may be a little while yet, but hey ! there's always plenty of rust to chop out of the cab while I wait. Pete
  23. The next task after fitting the the cam shaft is to replace the valves, lapping of the valves and seats was covered in a previous post. what follows will be common for all side valve motors with slight variations due to individual manufactures design. The basic concepts are also good for overhead valve engines to, the exception is side valve V8 motors we'll not go there as they are in a world of their own with split guides and other wired bits and bobs dreamed up by dear old Henry. This is the kit that's need for this job all pretty self explanatory with perhaps the exception of the spring compressor, that's the tool that looks a bit like a set of mole grips in the photo below more about that in a minute. Valve springs are stored on a board in the same order that they were removed, cylinder numbers 1 to 6 are marked on the board. In the photo below I have already fitted Nos 6 and 5 exhaust valves. In this engine they are painted yellow the inlet springs are a brown/red colour, often the springs aren't marked at all just plain steel. Bit more about springs in the next post. Here's a close up of the side valve spring compressor. A really useful tool to have in your box if you have a side valve engine. There were some cheap copies around on the web at one time. I'm told they are not very well made, originals like this one come up on ebay from time to time they are not cheap but well worth the money. You can just about do the job with a set valve spring compressors made for overhead engines but the proper kit makes the job much easier. Next photo shows the component parts that go to make up the valve and spring assembly, this is an exhaust valve for this particular engine but the inlets will be similar. Valve and spring are self explanatory Green arrow, Spring retainer these come in slightly different forms depending on the engine design this type is a Rota cap. On Long block side valve Dodge Chrysler engines it's fitted to the exhaust valves only. It's a small race that allows the valve to spin freely during the opening and closing sequence . Among other cleaver things It helps heat dissipation into the Stellite seat and prevents flat spots on the valve face as well as supposedly helping with cam lobe ware. Red arrows, know variously as Collets (I know them as this), Valve keepers or Cotters, what ever they'r called they do the same job. Namely to lock the spring retainer in place on the valve stem and keep a residual 'at rest tension' on the spring that keeps the valve closed tight on the seat. Note collets are cone shaped, the Rota cap has a matching angled recessed hole that matches the cone angle . Collets are fitted narrow end of the cone facing up into the spring retainer, at rest spring tension holds everything together. Blue arrow, grooves machined into the bottom of the valve stem. These locate the collets in place on the valve stem there are two on this particular design some manufactures engines will only have one you need to know what you have because the collet types are not interchangeable. The photo below shows what it looks like when assembled in the engine you can see the collets just poking out the bottom of the Rota cap the retainer will sit a little lower when there is residual force from the spring locking everything together. That will do for now more to follow Pete
×
×
  • Create New...