I have a 1969 ford FE that has been bored over sometime in it's life and now the timing chain needs to be replaced. I bought a brand new stock cloyes chain and stuck it in. It had miles of slop. Slightly worse than the one i took out. I contacted their customer support and the service manager said that maybe it had been lined bored. and that I would need an undersized chain either .010 or .005, and a measuring procedure. I followed it with a set of good quality calipers and I can't seem to get any good results. The cam nub (for lack of the proper term) and the crank seem to be on different planes. Where the nub is proud of the block is right where the tapper is on the crank. The measurement i got doing it anyway says that i need a .010 under chain. I thought i'd be extra clever and stick a bolt in the camshaft and use that for my measurements. The only problem is that it says that I should be able to use a standard timing chain. It occurred to me that the bolt hole may not precisely centered on the cam. The gear locates on the nub, and not the bolt. Do you guy's know how i could shop for undersized sets locally? The only things i can find are fancy racecar billet chains that i really don't need (150-200$). I just drive this car to work, and i'd like it to not run like absolute trash. The size of chains i need are. 5.034" and 5.039" for the undersized ones. Or should i just buy another stock chain? The timing gear sizes match exactly with the ones i pulled out of the engine. The original one i pulled out was a factory nylon gear as well.
Just advance the cam timing to take up the slack. A tight chain will causes undue were on the cam bearing and front main bearing.
Drill and tap the timing cover for a bolt. Then install a spring loaded timing chain tensioner from a British "Mini" Cheap via mail order https://www.minisport.com/12g2621oe-simplex-timing-chain-tensioner-pad-for-mini-a-plus-models.html This ^^^^ is the standard fix on Aussie Chrysler Hemi's [I've done this mod a few times]
I would get another timing set with steel/cast timing gears and see how much slop that has. It stands to reason that the original nylon cam gear is worn, and if the new nylon gear is the same size as you say, it is slightly undersized. Pictures would help.
So the new chain has more slack than the old how do you blame that on line bore. From the way things have going has Cloyes started out sourcing to China? I just did a brake job and replaced wheel cylinders with brand name parts 1/2 of them the bleeder would not seal made in China
Put the old chain back in, put it together, and then figure out what else is wrong with the engine that's making it run bad. It's not the timing chain, obviously.
Standard center line is 5.044". Easy way to see if the cam bolt is centered is to rotate the cam 180 degrees and measure it again. As @squirrel states, the chain is not why it runs bad. unless it jumped a tooth. That engine is notorious for bending push rods, and a compression test may be in order.
The chain i pulled out had well over 12 degrees of play. When i replaced the timing set the first time i bought a brand new complete cloyes set, put it in and it had even more slop. The line bore idea came from the tech manager at cloyes who i was talking with a few months ago. The nylon gear i was remarking about was still in the engine when i tore it down the first time. I was under the impression that an undersized timing set would use oversized gears to compensate. The gears i pulled out where factory ford gears.
That may be an option. But i build my cl***ic cars for reliability. A chunk of plastic on a spring doesn't seem like a 50 year fix.
I sounded like in your original write up you only changed the chain. I have never done this. All 3 parts or none and never a problem. Good luck.
Undersized chains are made to be used in engines that have been line bored (which may reduce the center to center distance), and uses standard sized sprockets. Using your "quality caliper" to get a true c/c distance- install a bolt in the crank and cam, measure the outside to outside distance of the two bolts, rotate the cam 90 degrees, measure again, rotate the cam another 90 degrees, and measure again. If all 3 readings match, the cam bolt is centered. Return the cam back to original position. Measure again, and measure the diameter of each bolt. The overall distance minus 1/2 the diameter of each bolt is the true c/c. Factory specs is 5.044" +/- .002. As the "new" chain has more slop than the old one, chances are the chain is bad. If the year of the engine is correct, then it is either a 360, 390, or 428 CJ. Doesn't matter as the distances were the same. In the years I was running FE powered Fairlanes, I never had to use an undersized chain.
"Generally, align honing will only move the crank to camshaft centerlines closer by 0.001- to 0.0015-inch. If the block requires align boring and 0.010-inch is taken off the caps, then several companies offer 0.005-inch-shorter timing chains to compensate." I lifted the above paragraph from Engine Labs Blueprint series. My advice is to buy another stock timing set from another manufacturer and see what you get. Not that Cloyes ****s or anything, but give another manufacturer a shot. The simple reasoning is that who the hell line bores a regular old run of the mill FE? You removed a stock timing chain, chances are the rest of the engine was just as stock. If it had a set of billet splayed 4 bolt caps, them maybe it has been line bored. Your stock block, most likely not. Try another chain and see what you get. If you are still having an issue, set up a mag base dial indicator and measure the actual movement you are getting from the cam gear. And post some pics. -Abone.
This Fe was worked over sometime in it's past. They bored the engine 40 over long before i was born. It's a 390 in a 1969 ford XL with 80k miles. For some unknown reason they worked it over when it was still a young engine, and stuck the 2 barrel intake back on it. Edit: I know it's 40 over because the pistons have it stamped in the top. I had the heads off when i blew a head gasket.
this is what the CLoyes service manager told me. I have gone through the measuring procedure and got strange results, I will be rotating the cam and retaking my distance and taking those to get a true measurement. This engine is a strange bird, The car is a 1969 ford XL (390) that had 72k miles when i picked it up (they are original, i confirmed it through some wear items and overall condition). The engine has been bored 40 over sometime before i was born, probably in the 90's. They put that sort of work into a low mile engine and stuck the factory 2 barrel intake back on. I have no idea if the chain i originally took out was factory, but the nylon gear sure was.
I would measure the width of the sprocket mounting surface on the cam, and the crank diameter. Then cut them in half and add the space between the cam and the crank to get the center to center distance.
When I was playing with Aussie Chrysler Chargers back in the 70's , the dealerships sold this part over the counter as a fix for a design problem.[So this was a 50 year fix for a 1971-72 Hemi 265] The Chrysler part was from an OEM part from a Hillman / Sunbeam 1725 engine [a division of Chrysler corp] but was the same style as the Mini part [I posted above] Here is the Australian Chrysler part they later retro-fitted as an OEM part. The fix was to drill a hole and poke a "****on head" Gutter bolt through the timing cover and weld the head on the outside. No nut was used on the inside as the tensioner couldn't slide off. https://www.ebay.com.au/itm/113746155708 Understand a timing chain is soaking in oil, so it lubricates the plastic. Toyota "Y" series use a plastic tensioner [these engines are the "King of reliability"] Lotus twin-cams used them in the 1960's and late model Ford Modular V8's use 2 plastic tensioners It's your call ....... You could also spend $100's on offset tunnel boring to raise the camshaft [and spacers for the cam bearings] of $20-50 on a chain tensioner and DIY it.
Why would i need to bore anything? All i need to buy is an undersized timing set. Cloyes can sell me one directly for under 100$. I was just trying to figure out if there is a way to buy them locally since it's the weekend.
I think I would try a different brand gear and chain, probably a roller chain. They are not that much higher and the quality may be better.
I just ordered another stock chain from a local place with their inhouse name. I'll toss it in tomorrow and see if it's right. But until then, i'm going to play around with measuring stuff and getting angry at myself.
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