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Hi guys. I have a 72 supreme with a 350 with about 170,000 miles. I don't know if the timing Chain has ever been replaced or not. The engine is out of the car and I'm about to replace the water pump. I can turn the crank about the distance between two of the teeth on the timing indicator before the rotor turns (about 1/4" Inch) which to the best of my measurement comes out somewhere between 1 and 4 degrees of slack. When I reach in to feel the chain through the fuel pump it feels quite tight. Not sure if it actually needs to be changed or not but I would like your thoughts. Thanks so much!
Chris
The norm is roughly 2 degrees from the crank to cam, 2 degrees from cam to dist. The bigger issue may be end float in the distributor. Fixing that might tighten things up more. .005-7" end float in the distributor shaft is good, so you can make it "click" end to end with virtually no perceived float - room for thermal expansion.
I would agree with MD in that it has probably been changed. No way the plastic gears would last that long. I would replace it. They are not that expensive. Since the engine is out I would probably pull the pan too. There could be some plastic from the original timing chain in the oil pump pickup screen. I would probably replace the oil pump while I had the pan off. This is where I would stop with the MAW's.
It is cheap insurance to change it out while you have the engine out of the car. I got a Cloyes set from Rock Auto for less than $40 shipped, thinking I might need it. Turns out I did indeed need it. The existing chain of the installed aftermarket set had stretched considerably.
Ok, thanks so much guys! Should i use an impact gun to get that gosh darn harmonic balancer off? And can anyone point me to a good thread regarding changing the timing chain and gears?
Thanks!!!
Ill be honest that i am afraid of really screwing up the timing by taking the timing gears off to put the chain on so any good thread that you can point me to would be greatly appreciated. Thanks for what you have all helped me with so far!
Ok, thanks so much guys! Should i use an impact gun to get that gosh darn harmonic balancer off? And can anyone point me to a good thread regarding changing the timing chain and gears?
Thanks!!!
The easiest way to loosen the crank bolt is to use a breaker bar with an extension pipe rested on the ground while bumping the starter. Retightening it is a whole different bag of cats.
Since I was performing extensive work in the front end and engine compartment anyway, I removed the radiator and shroud, then fan. Then I used an air impact wrench on the HB nut. It came off in literally less than one second! Just one touch of the trigger. When reinstalling, I used a fan holder/spanner against the driver's side frame rail to keep the HB/crank from turning, then torqued to 165ftlbs.
When I got the cover off, before working on the gears/chain, I rotated the crank until the alignment marks were centered/aligned with each other - no guessing on installation of new gears this way.
And redoldsman, you suggested replacing the oil pump. whats involved with that? The MAW's could go on forever lol! Thanks!
I have never replaced one on my 72 Olds but with the engine out of the car there is not much to it. A factory shop manual will give details. If you don't have a factory shop manual, you should get one. They are on ebay and prices vary but you can find one very reasonable. You might give thought to replacing the rear main bearing seal while you have the pan off. It would be a lot easier now than when the engine is back in the car.
Ok, this is very helpful. Yes i do have a CSM but it just says "remove harmonic balancer bolt" lol. It also says that the crank sprocket MAY need to be pulled off due to tight clearances, and may not come off easily. In your experience, do i need a puller to get the crank sprocket off?
Also So i found a link to a post on replacing the rear main seal here https://classicoldsmobile.com/forums...-question.html
is this my best bet for replacing the rear main seal with the crank in? I wasn't planning on removing the crank. Do these seals come in the fel pro engine full set or would i need to purchase this separately? Its funny how fast the MAW list grows! Last week i didn't even know what MAW stood for! Thanks so much guys!
And back in the game, are you saying that as long as the timing marks align on the cam gear and the crank gear then i should be okay? So theres only one way that they can go on? Thanks!
Chris
And back in the game, are you saying that as long as the timing marks align on the cam gear and the crank gear then i should be okay? So theres only one way that they can go on? Thanks!
Chris
There is only one way the factory type can go, but if you get the roller chain type with the different keyslots for advance or retarding timing be careful to get the correct marks aligned. Also you can wedge the flywheel gears to keep the crank from turning to remove the crank bolt .
Do these seals come in the fel pro engine full set...?
They're for a F_rd or a Rambler, so, No.
Originally Posted by Oldssupreme
... are you saying that as long as the timing marks align on the cam gear and the crank gear then i should be okay? So theres only one way that they can go on?
Yes... There's only one right way. The manual tells you what to do.
Ed and eric, thank you! Eric, im embarrased to ask, but what exactly is a cold chisel? So youre saying if it doesnt come off easlily i should break it with the chisel and slide the new one on? All in all the replacement of the timing chain and gears doesnt sound THAT hard of a task. Was i wrong in being so nervous to do this?
Thanks guys!
Chris
Oldssupreme - here is a pic of my installed new timing set. It is by Cloyes and has the adjustable alignments for advancing or retarding the timing as noted by edzolz above. Note that the key slot for 0' does NOT line up directly with the timing alignment marks on the gears. The slot for 0' is clockwise about 45' from "12 O'clock, High." Each of the unused key slots are marked in 2' increments such that "A2" = 2' advanced timing, and "R2" = 2' retarded timing, etc.
Both of my original gears came off very easily, when worked together/simultaneously. Installation of new gears - same process - test align the gears with markings aligned, then remove gears, keeping them aligned, install chain to both gears and gently slide them on the shafts in unison. It might take a few tries, but there is no real effort involved.
Rich thanks so much for the info. I have to work the crank sproket off tomorrow. It didnt want to come off today at all. Should i put the cam sproket back on snd try to work them both off again?
And ill tell hudson hes getting a raise lol!
Thanks again!
Chris
Should i put the cam sproket back on snd try to work them both off again?
That won't help.
If you can't loosen it up and work it off, just split it.
Also, when you install the new timing set, make sure to take a picture of it, so that if you have any questions about what you did later on, you can look at the picture, instead of taking the motor apart.
Thanks Eric!
Also, regarding the rear main seal, it was suggested that i replace that as well. I have a rope seal that came with my fel pro full engine kit. I have seen lots of instructionals on how to install this with the crank out, but not too much with how to install it with the crank left in. Any ideas?
Thanks!
Chris
Chris,
Since you already have the cam sprocket and chain removed, you may be able to get a 3-arm gear puller to reach the gear and pull it off - nice and even-like.
I have a rope seal that came with my fel pro full engine kit. I have seen lots of instructionals on how to install this with the crank out, but not too much with how to install it with the crank left in. Any ideas?
It can be done (there are special tools for it), but why not take the opportunity to install a modern neoprene seal instead?
Rich, good idea, i have one that came in the harmonic balancer removal kit. Ill try that first and if that doesnt work then ill try eric's idea of whacking it with the cold chisel. Eric, in order to install a neoprene gasket does the crank have to be out?
Thanks!
Chris
Eric I apologize for all the queStions but I've never done this before. How do i lift the crank to get the neoprene seal in? Does the oil pump need to come out first? Thanks!
Eric and rich, does this look right? I didn't move anything since I took the gears off so the new set is installed in the same position as the old right? Rich this is the stock non adjustable cloyes set 3006k I think the number was. Thanks guys.
Chris, not having seen the "before" pics, I can't say for sure that this is correct. In the picture you posted above, the timing dots on each gear are not in alignment, and subsequently may not be correctly lined up for TDC on Cylinder 1. Did you obtain dot and TDC alignment before R&R of the gear-set?
On mine, before I disassembled, I hand turned the crank until the dots were in alignment and ensuring that cyl1 was at TDC. That's when I pulled both gears and the chain, then installed the new set.
Whether you did or did not obtain TDC at cylinder 1 with the dots aligned, before removing the old set, will determine your next step. Before it will start and run, you need to have cylinder 1 at TDC and the dots aligned, and the distributor's rotor pointing at the cylinder 1 spark plug lead. I don't mean to be vague, but I'm at work now and can't reference my assembly manual.
If neither the crank or the cam moved AT ALL, then you're fine.
BUT... To be SURE it's right, you need to get #1 to TDC (best if you measure with a dial indicator, or use one of those screw-in piston stops), and then set it there.
Ok. So is it really just that easy? I remove the chain, reinsert the crank bolt and rotate the crank so the timing dot points up, then rotate the cam sproket by hand until the timing dot is pointing down, then fine tune so they are exactly aligned with eachother, then take off the cam sproket again, wrap the chain around both sprokets, and reinstall? Then make sure that #1 is a tdc using your previous instructions?
And eric, how do i lift the crank just enough to get the neoprene seal in?
Thanks guys!
Chris
To avoid the chance of your balancer giving a false reading, it is best to use a piston stop screw to determine the exact location of TDC (later balancers have opposing chisel marks on their halves so you can see whether they've slipped, so if you have these, you can use your balancer reliably, and only need to determine TDC independently if you're obsessive).
Then you set the engine to TDC (dot on crank sprocket should be at 12:00), rotate the cam so that cam sprocket dot is also at 12:00 (NOT at 6:00), double check that your distributor rotor is at the #1 position, , then remove sprockets, attach chain to sprockets, re-install, and re-check that both dots are at 12:00 and rotor is at #1.
As for the rear main seal, you turn the engine upside down, remove the rear main bearing cap, and loosen the other caps (or just remove them all - Good time to do a quick PlastiGage check -- Hey, you M-A-W! ), and you should be able to lift the crank about an eighth of an inch away from the rear main bearing and seal.
Eric, regarding the chain, was i wrong in thinking that the crank and cam sprockets should be facing eachother? You said the cam should not Be at 6:00, but rather 12:00. I thought it should be 6:00. Chris
July 19th, 2016, 01:44 PM
), and you should be able to lift the crank about an eighth of an inch away from the rear main bearing and seal.
