zman Posted December 4, 2006 Share Posted December 4, 2006 I noticed on the tear down of a V-12 that the previous re builderhad installed the none rotatable valve assemblies, Using the later F/HFord assemblies These assemblies should not be used on the Lincolnwith hydraulic valve lifters as they do not allow for requied clearances.The valve retainers at the bottom of the stem sit to close to the topof the push rod bore and creates interference for removale of the keepers,in adition to checks required for checking clearances of the stem and the colapsed push rod on assebmbly.Now I'm wondering if the Rotatables are still available, I noticed that the 49 to 51 F/H fords did have rotatables.Bill :shocked: Link to comment Share on other sites More sharing options...
peecher Posted December 6, 2006 Share Posted December 6, 2006 Bill, sounds like a couple of things could have happened here. Someone may have used an aftermarket valve that was "close" but positioned the spring retainer lower on the stem. The straight stem valves used on the '49 to '53 Fords position the spring/retainers exactly in the same location as on the regular mushroom style stem used on the Zephyrs and pre '49 Fords. The mushroom style stem valves are still available if you choose to use them. Another possibility is that the valve seats and/or the valve heads were faced/ground way too much positioning the stem further down and approaching the boss of the tappet bore. The spring retainers were fairly close to begin with making clearance checks difficult. To my knowledge there were no "rotators" with either design of valve stem for Fords? If the valves themselves are the problem ( not Ford) you may be able to use either the straight or mushroom style Ford valves when you rebuild. If the valve seats in the block have been ground too deep you may have to have new seats installed. Let us know what you find. Link to comment Share on other sites More sharing options...
zman Posted December 7, 2006 Author Share Posted December 7, 2006 Hey peecher, the valve seats look good and they do not appear to have beenre-surfaced.I have attached a jpg on valve assemblies with the mushroom types I pickedout of my parts bin.It seems that I can get the later ford rotatingassemblies from job Lot.Made a few measurements on the bores and it was a 2.875 + .030, the readingsare to high and may have to go to the 15/16th's bore size.The crank rod Journals are 2.125 and .020 undersize,but that may create a problem unless I change the crank with a 2.250 journal's.Possibly it would be best to sleeve it and stay with the 292 Cu.In.The cam shaft is scored badly on some lobes, so it has to be re placed Link to comment Share on other sites More sharing options...
peecher Posted December 7, 2006 Share Posted December 7, 2006 Bill, sleeving one of these engines is fairly expensive and you still have to buy new pistons. Unless there is a lot of taper or deep pitting in the bores they should clean up at .060" over or less. The block could even be safely bored another .0025" to make it a standard 2-15/16". Oversize pistons along with all other new parts for rebuild are available. The post-war crank would be the one to use not so much for the size of the journals but because there are no sludge traps to clog up. If your oil passages are all clear in your crank you may be ok? New bearings in standard and undersizes are available for these cranks also. I recently finished rebuilding a 292" '47 engine and used the Ford change-over valve kit to redo the valves and guides. The only advantage doing this is in future disassembly ease and perhaps the seals on the intake guides. Your camshaft may be grindable, mine had some pretty good size nicks in some of the lobes and they were able to regrind it. I'd have it checked before condeming it. Lobe(s) can be built up if necessary but this can too become expensive so you have to weight the costs. I would regrind or micro polish the cam in any event along with resurfacing the lifter bodies.There's probably enough meat in the cylinder walls that you could even go .010" to .020" over on the 2-15/16" bore. I'm presently doing a "big " 12, boring a '42 block to 3-1/16" and using standard early Ford pistons. I'm holding my breath on this! Link to comment Share on other sites More sharing options...
zman Posted December 8, 2006 Author Share Posted December 8, 2006 Thanks Peecher,sounds like a winner,looks like I can go with the 2-15/16bore, which will also take care of some of the taper I noticed.I'll see what I can do with the cam and about the crank,We have a Winter Swap Meet comiimg up in Feb, at Lancaster Pa.I'm sure I can pickup the later crank and possibly a better camI agree on the valves,I see where the later Flat heads have the correctsizes of the rotatable valve assemblies, all the dimensions are the same as the Z mushroomed Valves,including the shoulder just below thevalve head,which I assume is a stop for the valve guides.I also noticed on this engine the teeth on the fly wheel is not correct,'also the weight is 40.5 pounds and should be 34.5Probably a truck Flat head fly wheel!One other question,I see where Earle Brown has adjustable lifters, and wondered if you have used those on any V12's and would the clearancesbe the same as a later flat head?I know the clerarances for the 36 Z's,but with the larger journals changing the stroke.I'm assuming they should be the same as the later flat heads"Bill Link to comment Share on other sites More sharing options...
Guest imported_V12Bill Posted December 8, 2006 Share Posted December 8, 2006 You don't state what year V 12 you are working with.Peechers advise on the crankshaft is good. The post war crankshaft offers more meat on the journals, but you aren't going to race this engine are you? I would be cautious about going too large on the bore. Egge will make up pistons any size you need. You shouldn't bore in excess of what you need to clean up the bore. Some day it may need to be bored again and you don't want to strike water when you bore.Solid lifters, adjustable or solid, should only be used with a cam that is ground for solid lifters. I have seen a couple of V 12s that the lobes were badly worn when solid lifters were used. Cams for hydralic lifters are ground to slap the base of the lifter sharply in order to close the check valve. Solid lifter ground cams have a slopping step on the lobe to ease the valve up and down.Bill Link to comment Share on other sites More sharing options...
zman Posted December 8, 2006 Author Share Posted December 8, 2006 Ok V/12 I'll be U-teeing the block anyway, so I can decide then,howeverthe way it's checking out and with the taper in some of the bores15/16 would take care of it.This V-12 block is a 40, since the bores were originally 2.875 and bored to .30 over, I believe it was run low on oil, other wise the bore measurements would not be so out of round.I'll check those cams out, including the 36 Z CAM which lincolnused solid lifters in.Thanks for the input.Zman Link to comment Share on other sites More sharing options...
peecher Posted December 8, 2006 Share Posted December 8, 2006 Bill, clearance ramps for adjustable tappets can be easily added when the cam is reground. If you use the adjustable tappets the clearances would be the same as the '36 and '37 12's. Many guys have gone this route and there are some advantages. You can eliminate the secondary oil line that feeds the lifters but you must provide a pressure relief passage at the front relief valve in order to assure lubrication to the timing gear. With the proper cam grind the engine will run as quiet as a flathead Ford. The hydraulic tappets of course will run a tad quieter as long as as long as they are in good shape and oil pressure is decent. Link to comment Share on other sites More sharing options...
zman Posted December 10, 2006 Author Share Posted December 10, 2006 Peecher I did find where they do grind the cam for either hydraulic or solid lifters, so I got to make sure when I finda new cam it's ground properly.I also see that Lincoln hadhydraulic lifters in a one piece design, with the valve assemblyas part of the push rod body and the 2 piece consisting of a separate,hydraulic push in the push rod body, The only onesI have worked with is the later.It appears that I can go easily with the 15/16th's boreI made some measurements using clay, packed in various placesand subtracted the differences, and came up with .0190 to .0196for the remaining cylinder wall, plenty of room for boring to 15/16I'll still do the UT thoughBill Link to comment Share on other sites More sharing options...
peecher Posted December 10, 2006 Share Posted December 10, 2006 I think you meant .190" to .196" for the cylinder wall thickness? I've never seen a Zephyr engine with those one piece hydraulic pushrods. I'm guessing, but that may have been the design of the very first ones used in '38? Old Henry was loathe to pay anyone any royalites but probably decided to use the Eaton design for all the later engines? Just speculation. The one piece design seems similar in concept to "modern" hydraulic lifters but there might have been some good reason to discontinue their use and someone out there might have a better answer? Link to comment Share on other sites More sharing options...
zman Posted December 10, 2006 Author Share Posted December 10, 2006 yeah that's what I mean't .190 & .196, Guess I should review my postsbefore I send Ha!Bill <img src="http://forums.aaca.org/images/graemlins/mad.gif" alt="" /> Link to comment Share on other sites More sharing options...
leb Posted December 28, 2006 Share Posted December 28, 2006 To Zman, I have a good cam (marked 06H) i just took out of a bad block.Ihope to be at the Lancaster swap meet. I'll bring it, plus a whole bunch ofother stuff. Larry Butcher Link to comment Share on other sites More sharing options...
zman Posted December 28, 2006 Author Share Posted December 28, 2006 Thank's Larry I'll see you there, I;ve just taken the Block to the Machine shop, so the timing is just right.I'll be interested in other stuff too.Bill Link to comment Share on other sites More sharing options...
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