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
Been plugging away at the intake spacer Drilled and tapped for the fuel manifold Free hand milling Will now need to do some die grinding to blend in the contours
Such an excellent build with so much information. Thank you for doing this thread. Keep the updates coming.
Starting to look at the cylinder heads There was already a problem I knew about that being the 2 center cylinder domes not being cut to the same depth on the passenger side part numbers on these heads are 68-6049B 68-6050B Which makes them a’36 design Casting dates of 8-13-46 10-22-46 So replacement heads My book gives a combustion chamber volume of 75-78 cc for a compression ratio of 6.3 to 1 From what reading I have done.050”to.060” can be milled off One problem being how thin it is to the water jacket You can definitely put your fingers into the water jacket and feel how thin it is Did some preliminary measuring using tin foil I don’t have a used compressed gasket to use so most give a compressed gasket measurements of.050” and if you are looking for.050” clearance between piston and head and valves to head you are looking at zero clearance with no gasket With the measurements I got don’t think these heads have been milled before and being replacement heads that would make sense Taking.050” off the heads I think would still give sufficient clearance over the valves and pistons the exception being the 2 cylinders mentioned above So some hand massaging of those areas will have to be done For education purposes will try to come up with a way to get a before and after cc volume measurement of the combustion chambers Also I like the very deep transition area in the combustion chamber so I shouldn’t lose airflow when milling the heads and will add turbulence with the squish area over the piston Next task is to actually get them securely mounted on the milling machine table
Came up with a cheap way to cc the combustion chambers Found a piece of plastic that was big enough to do 4 chambers at one setup found this turkey cooking kit in the kitchen and with some bolts to hold the head was able to get measurements pretty quickly results 1. 80 cc. 5. 78 cc 2. 78 cc *. 6. 80 cc 3. 76 cc *. 7. 78 cc 4. 78 cc. 8. 78 cc * two center chambers mentioned in previous post currently working on a fixture for mounting heads on the milling machine hope to have more on that next week As a side note Been back to working on my new shop Got 50 amp electrical service installed So moved the welder and welding table from the back door of the house to the shop When the heads are finally bolted to the block the engine will then be moved out of the basement and put on the run stand in the shop to get finish assembly and what ever work that needs to be done on the run stand (radiator,exhaust,fuel,battery,control panel ) Still working on a floor in my lean to shed so I can bring the rest of dad’s equipment including the shop air compressor which I badly need and the hydraulic press and some smaller bits and pieces Once I get the engine running I can then bring the rolling chassis home where it will be disassembled the frame painted and then the engine and trans can be installed in the frame (almost forgot that the steering box has to be installed before the engine and that the left hand cylinder head cannot be removed when engine is installed because of the steering box that is why I am doing a run stand so I know that everything is good before being installed I can also easily install different carbs manifolds or other parts on the engine while I am working on the frame) For those new to my build here is my steering box installation which can be found somewhere in a early post
Posting a little late today Was just able to grab an hour today to continue the fixture for milling the heads Using a 1/2” plate drilled and tapped 4 holes 7/16-14 and made studs to hold the head I will use locknuts so I can adjust the level of the head drilled and tapped2 holes 1/2-13 for bolts to hold the head down was worried that this wouldn’t be rigid enough but it seems real solid Still have to finalize it Need to drill holes to bolt it to the mill table but it is looking very promising Hopefully soon will be making chips Actually been preparing for this for 4 years that’s when I made the fly cutter anticipating the need to mill the heads
Part 1 Got a lot of material today so will break it up into a couple of posts Continuing with the head milling fixture My plate wasn’t flat so had to mill it flat was also a good test for my fly cutter spent several hours tramming the mill Got it as good as I could about .0007” on a 9”dia. then I was ready to mount a head All the preparation I have done was worth it Head was easy to set up and adjustments were precise and repeatable Head was staple and solid Started making some cuts the carbide inserts dull pretty quick (probably a combination of cheap inserts and using lathe turning cutter for a milling operation but it is a positive rake insert) I did find that I could touch up the inserts with my diamond file Hopefully I can make them last through the second head Was left with a slight parting line when I finished but you can not feel it That.0007”from above well pleased with the final result Better than I had hoped for again all the preparation made it seem easy all the pitting from corrosion was cleaned up Removed.050”
https://www.fordbarn.com/forum/attachment.php?attachmentid=5732&d=1275935985 Part 2 While doing some research I found this file on the ford barn It’s a comprehensive guide to compression ratios for flatheads My interest was on page 10 Plugging in my 78 cc combustion chamber and my.030”over piston I have a compression ratio of 6.28:1 After milling I couldn’t wait to see the difference so while it was still mounted on the mill did a quick volume check on cylinder 7 Wow Brought it down to 68 cc Better than I had expected Compression ratio 6.96:1 This is great a 3/4 point increase in compression with a more efficient squish area and little reduction in air flow
Part 3 Took video https://youtube.com/shorts/IcwwDNITsxM?si=df3N_xQWAh20pcln https://youtube.com/shorts/FukwhIDC_p0?si=4_lueAch8vArtD-f https://youtube.com/shorts/ryvhpOsWpSo?si=7iPP5vB6HUPO1QJJ
Still working on the cylinder heads but taking a break this week A shot of the progress more to come soon finished up the intake manifolds finished the porting and profiling made a carb block off plate (got fancy added my logo) here is some useless info Carb spacer started at 1281 grams ended up at 662 grams Pre war swap meet is coming up this week in Luray Virginia https://www.mapwsm.com/ Will give a review next week Always a good time
Swap meet recap Another good year at the pre war swap meet A pair of extended shaft small logo 59 carbs (obviously the end carbs of a 3x2 setup) carbs appear to be in great shape chokes deleted Be interesting to see what jets and power valves are installed I’m used to seeing nails used on my old tractors but didn’t expect to see them on a hot rod setup a large logo 59 The main body appears to be old but the top and base appear brand new no play in the throttle shaft at all to be totally honest I have been thinking about getting one of those cheap repro 94 carbs for the initial start up but with a gasket kit and new accelerator pump and power valve this will be better (got this carb for 5$) Paid a little money for this pieces but I think they may help me in a tight situation If you remember when I was working on generators and thinking about a mid mount fan I picked up one of these a v8 wiring harness that I was told will fit a model A a nice little rear view mirror fuel pumps a fire wall this might help me for ideas maybe using this on the inside and making a second fire wall on the engine side picked up some more spare tire holders use them for making hose reels and then to prove that I am sick with flat head fever came home and followed up on a lead so now I need to finish the heads so I can get the’34 mounted on the run in stand which will free up the engine stand for the’35 Nothing like a weekend of spending money to get you motivated I’m burning up with fever Some random photos of the swap meet Old saw mill power plant didn’t get the belt pulley in the picture
Just a little update Haven’t finished the heads yet but I’m really close I’ll do a complete review when I’m done It’s been a real learning experience and I would definitely do some things differently Got my old shop compressor moved this will really increase my productivity While I was at the old shop I looked in on the rolling chassis This is what the firewall looks like I think that was a good 25$ spent I think I will be able to use some of it especially around the drivers area ‘35 engine Motor is locked up but I will first clean it and then take off the heads pan and all and clean some more I learned from the first engine you don’t even start working on it until you clean all of that old qunk out The interesting part is that it looks like all the original hardware that maybe this engine hasn’t been into before That would be great because those floating rod bearings are alot easier to come by in standard size or even.002” undersized But of course this engine is just another distraction The only difference between the’34 and’35 are the’35 has studs for the main caps and there first attempt at crank case ventilation so I do have some spare parts for getting it to run Also it would be nice to know its condition for use as a backup motor as often happens my mind starts thinking about other parts of the project I would like to run 2 oil bath air filters That would involve siamising the 2 together That would put the cut line here That might be hard to do I’ll have to think about that Haven’t found a match for the filter I have yet Maybe some s curve pipe
I just found this thread...outstanding work, details and thought process! Thanks for taking the time to bring us along. I too have an all manual milling machine...I really appreciate your work (especially the free hand manifold spacer!), and effort to make and set up fixtures.
Wow its been a month since the last cylinder head update I had actually gotten a little frustrated and took a step back but this last week I got motivated and finished the heads Everything went great after the break This first part will be what work I did and the final results and part 2 will be what I would do differently and some random thoughts We left off I had milled the heads (.050”) now was time to check piston and valve clearance It suddenly dawned on me why working on flatheads is so difficult When I worked in the race shop 35 years ago we checked piston and valve clearances all the time but you did it with dial indicators where you got accurate readings because your valves and spark plugs were overtop the pistons and any machining that was done was done to the piston dome and not to the cylinder head Valve in block engines are completely different you need to use clay or tinfoil to check clearance and I found this to be very difficult to get accurate measurements and time consuming This is the reason I chose going for zero clearance with no head gasket The gasket giving you your clearance I started with the head (right side) that had problems with the 2 center dome areas Dykemed everything then placed the head on the block with 4 studs then turned the motor over several times while gently rocking the head back and forth when ever the head raised up off the block got a definite line on the pistons of the 2 inside cylinders after much thought came up with a way to remove material in a perfect circle then took sanding disks on a drill to blend together this is where I got really involved and didn’t always take pictures Keep repeating procedure removing material where needed that went better than expected then turned my attention to valve clearance I had bought large end mills several years ago just for this job Settled on the 1 3/4” end mills don’t cut flat which in this case is fine because the valves are at an angle to the head I also adjusted the fixture to help with this angle (see part 2 post for more detail) again didn’t take alot of pictures at this point Repeated procedure until all valves are clearanced Moving on to head number 2 (left side) Had to remove along the perimeter of the dome area for all 4 ( no clearance issues on the middle or center of the domes for all 8 just the outer perimeter) You all have probably seen this diagram there is a call it 3* difference in valve angle between the right and left side and that makes a huge difference in valve clearance This is where I got frustrated and took a break before I messed something up Finally settled on using a small stone in the die grinder to clearance the small area of interference on each valve and then blending Final results combustion chamber volume before and after 1. 80 68 cc 2. 78 68 3. 76 67 4. 78 67 5. 78 69 6. 80 70 7. 78 69 8. 78 68 And by my previous calculations I am calling this a 7:1 compression ratio with enhanced squish area and increased air flow around the valves Next will be head stud install and capping off the short block
Part 2 Maybe not a good idea to remove.050” from a stock head with a high lift cam? I think with some modifications to my setup it can be done much better and easier I have since tapped the two remaining spark plug holes in my fixture so there is support when milling valve pockets have also added bushings for the spark plug holes would also love to have a radius end mill for the valve pockets but I don’t see that happening I had used the jack screws to adjust for the valve angle (just guessed at it) I think I can install jack screws on the fixture plate and adjust the whole plate then use an angle finder to get a precise angle for each cylinder head Would also like to make a dimensional drawing of the cylinder head (have looked for one but haven’t found one) so I can center over each valve for making my cuts ( much like a modern day cnc mill) I know they also made a valve pocket cutting tool that used the stud holes I didn’t do this but I think you can use a feeler gauge for when the head lifts up to determine how much material to remove or even calculate a smaller clearance My dad had made this lettering fixture and it actually fit the plate (struggled with the spacing at first) so now when they auction off my estate somebody might actually know what it is Would also like to have a cutter for the domes ( ol’ Ron talks about them in his book) But that might be beyond my capabilities Maybe if I had a set of aftermarket aluminum heads it would be worth while but the prices on 21 stud speed parts are pretty stiff ( that’s why I like cast iron heads) The new’35 motor will have the flat top piston so there is no advantage to milling those heads other than to gain compression and you lose all of your airflow then I really hope those aluminum heads don’t have to much corrosion they look good on the outside I’m dying to get into that motor but I need to get the’34 finished
Came up with a quick drawing of the cylinder head if anyone sees a problem with any of the dimensions let me know
The Jalopy Journal
