You get 2 postings this week Pistons The first thing I noticed was the pin retaining clip groove was much smaller than the clips that I had Van pelt gives a dimension of .041” wire thickness I matched up some retainers from McMaster Carr they come in a bag of 50 so I have extras The pins are also different these must be the tapered wall pins that people refer to The old pins weigh 82 grams the new pins 67 grams The old piston and pin total weight is 385 grams New piston and pin weight is 395 grams Balanced the pistons by putting them in the lathe piston and rod assemblies installed smoothly rod side clearance of.014”-.019” While looking for my ring compressor I did find these each one made for a specific size Cool Up next will be valve assembly
Got a lot to cover so this is going to be a lengthy post I was going to taper the valve guides (like everybody suggests doing) by wiring the split guides together and putting them in the lathe but found that the guides are already flush with the port difference in one piece valve guides? difference in early block? Don’t know but didn’t have to modify guides Next was getting installed spring height Didn’t have a good way of measuring until I I remembered the drawer in Dad’s drafting table (Dad’s memory is going to be playing a big role in todays post) Found these inside measuring caliber after measuring all of the valves it was time to look at spring pressure When I worked on cylinder heads at the race shop as a young man we used a fixture like this when I started working from my dad’s shop he made me this fixture I remember asking him how do you know that the gauge is reading actual lbs He gave me some scientific explanation about the size of the piston and alot of more detail that all went over my head But I see that the spring checkers they sell now are very similar like always Dad was way ahead of his time My spring install height ranged from 2.145”-2.200” With stock being 2.125” my numbers sound right for old valves that have been previously ground With a number of 2.165”and a .060”shim I have readings of 50-55lbs seat pressure and 100-110lbs at.365” valve lift Ol Ron says 50 lbs seat pressure is all you need so I’m good To keep everything in order I had laid everything out on a sheet of packaging paper with all my notes written right on the paper I’m thinking of framing this when I’m done Right before I was going to assemble the valves I was watching one of Mart’s videos and he was talking about how to tell exhaust valves (intake and exhaust are the same size) from intakes Exhaust valves are not magnetic Of course I didn’t mark the valves when I disassembled I was just going by the shape of the valve (the flatter ones being intakes) Mart was right the exhaust are not magnetic or slightly magnetic the intakes are definitely magnetic I was right too Now time to assemble the valves again using one of dad’s old tools upon disassembly I had chipped some of the valve guides Dad had always kept a flathead valve assembly on his desk (could be a 8n tractor aren’t they the same?) so I am using that guide on number 8 exhaust closets to the driver Cam timing Had to find TDC Using the positive stop method Cut a slot in a bolt for a pointer made a pointer for the crankshaft pulley after marking the pulley I put it in the mill on the rotary table Put notches at 0*,5*,20*,25* btdc Smaller notches at 2.5* and 22.5* For ignition timing Also notches every 45* for valve adjustment or diagnostic purposes next put the valves on number one to zero lash and checked cam timing intake Exhaust Everything looks good I’ve had this cam gear for a couple of years was never satisfied with it Bolt holes are sloppy and the shoulder bolts that came with it just make it worse Went to my local tractor supply store and bought some 1/4”spacers and some grade 8 bolts Reamed out the spacers to5/16” cut to length then reamed out the gear to 3/8” and pressed the bushings in cut the bolts to length You have to be careful on the length they go thru the cam and into the thrust face Oops can’t upload anymore files End part 1
Start part 2 the last thing I wanted to do was check lifter rotation on my hand finished lifters Well I don’t have lifter rotation or very little I think I put to much of a radius on the lifters After alot of contemplation I decided to order a new set of lifters but I am still thinking of ways to salvage the originals I think first I need to grind them flat Ford lifters are 1”so they will fit a collet on my index fixture it’s my understanding that the radius is 96”(8feet) on the lifter So here is a rough outline just some ideas right now but at least I will have some new lifters to check out rotation and profile I have got a whole lot of work to do yet before the valves need to go in Also for those of you installing higher lift cams you differently need to drill holes for valve adjustment and I would drill them even lower down than I did I had done a preliminary adjustment like Mart does so your final adjustment is very little You’re all caught up now I need to do some more thinking on the lifters but I don’t want to kill my new cam so I might install the new lifters and put the old ones on the shelf for another day I’m curious to see how much lifter rotation there is with a new lifter also I haven’t checked the 14 other lifters yet Tell next time
I will start this post with a video I found about flat tappets It really says what I have been finding out thru my own findings and what I have been reading My new tappets arrived and they look great they do have an issue that I will talk about in a minute The ones that I got are identical to the Johnson lifter even down to the adjusting screw New lifters have a weight of 82 grams to the original 78 grams the isky instruction gives a cam taper of.001” I have actually measured this cam and it does have a.001” lobe taper So if you want a corresponding taper on the lifter you would want .0005” over half of the lifter I have even read of .0002” Set up to measure the new lifters measured all 16 and they were the same at.001”(which is the number I will try to get when I recrown my originals anything smaller is to hard to measure) then started to check for lifter rotation I am having some trouble with burrs in the lifter bore I think from where I drilled the adjustment holes so I need to remove the cam and run a brake hone thru the bores But I do have lifter rotation (I have turned the motor over so many times you can actually smell the rings seating in) Was having trouble with setting valve lash on some of them that is when I discovered this the adjustment screw threads aren’t parallel with the body The adjustment screw face was ground with the screw installed in the body so depending on how you have it positioned you can actually double the error So my solution is to remove each screw mount it in an original lifter (which are straight) chuck it in the lathe and face the screw and also add more chamfer that should minimize the error and give the best surface area for the valve stem I also feel that the out of square adjustment screw can effect the lifter rotation I still plan on working on the original lifters but that will be a future project I have really gotten bogged down with these lifters and need to move on I have thrown out the spin fixture idea I can face the lifter flat with a carbide bit in the lathe and then get the.001” taper I measured up to a.008” taper on the ones I did freehand I also think my finish was too polished I think I can get them serviceable if I was to ever buy a used race cam!! I don’t know if anyone caught it but I had a brain fade when I was notching my pulley in my last post I put a notch every 45* when I needed only 90* Found that out while adjusting valves totally freaked me out for a while But I do tend to get confused when talking cam timing Hopefully by next week I will have the valves installed and we can move forward
I have often read that the valves are noisy on the flathead This was even addressed in my old repair manual particularly the square of the lifter and valve stem
I had read about modifications to the model A oil pump decided to look at my rebuilt’34 pump The shaft is already turned down on these pumps so I just opened up the hole that comes out of the pump and into the block used o-rings like Mart did drilled a hole in the casting for safety wire the bolts that hold everything together installed the oil pump idler gear had gotten a new 50# spring and plunger for the pressure relief valve in the front of engine the plunger was obviously to long probably meant for blocking off the relief port when using a later pump that have a built in pressure relief valve next will be flywheel oil pan and front timing cover
No the con rods are supposed to have cotter pins but because the nuts I’m using are not castled I don’t have room for one Also the one rod that I had to use washers on doesn’t have room for safety wire either
Flywheel installed My safety wire skills are not the best in cramped areas and since I have been following the old repair manual I checked the run out it gives a limit of.005” I got.003” on the outside of clutch face and.0045” on the bore The manual reads that you can turn the flywheel 180*on the crank and recheck but I did mark the flywheel when I disassembled the motor and reinstalled it that way And installed the clutch and pressure plate
Needed to make a new dipstick tube but didn’t know what length so I put 5 quarts of water in the pan and then allowed for the oil pump volume That makes it level with the windage tray Installed the tube fitting installed the sleeve for the new one piece front seal When pressing it on it developed 2 creases where it went over the key way cutout Gently massaged ,filed and polished it back into shape a lot of time can be used up on little stuff like this water drain peacock with all the beating and banging I did on the oil pan it had a twist and the holes didn’t properly line up So instead of enlarging holes I opted for studs This worked well also holds the gasket in place what I didn’t account for was how difficult the cork gasket that goes over the rear main was to install Should have glued this in place before I started Was worried that it was out of place but was able to get my phone in the starter hole and get some pictures Looks okay keep my fingers crossed used these serrated flange nuts for the pan so I don’t have to use lock washers and the front timing cover has to be installed at the same time when I don’t have real Henry hardware for the outside parts I take new hardware and machine off the markings give it a chamfer then bead blast and use gun blueing then soak them in oil motor mounts installed
Mixing it up this week I’m back to intake and carbs As mentioned I’ve got two different y manifolds one single plane and one dual plane I want to use the dual plane did the machining still need some hand porting the problem is that it is shorter than the other one and will have clearance problems with the generator I happen to find a chunk of aluminum and because I couldn’t find any dimensions I made up a drawing for a 3 bolt carb mount did some machining I wanted to make my own spacer because the ones that you buy don’t match the shape of the manifold or the adapter so they look added on I plan on shaping the spacer so it blends in and will look more one piece while I was taking pictures it occurred to me that I should leave a boss for a fuel manifold to mount too then I thought why not make the fuel manifold integral to the spacer that’s what I’m going to do should be one of a kind Also needed to flatten the castings where the nuts go so they bolt up flat Found this setup that my dad had put together Worked really well also with all this manifold thought it best if I added some heat back So put some 3/8” holes in the plugs I had made for the exhaust cross over here it is with the generator all the way up there is going to be nice spacing between all the components Nothing is going to look to crowded and with this engine being mounted low in the chassis and flatheads being short the elevated carbs should bring a good visual
The Jalopy Journal
