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Technical Shop => Engine, Transmission & Rear End => Topic started by: xx88man on July 01, 2021, 11:24:21 AM

Title: Timing chain replacement
Post by: xx88man on July 01, 2021, 11:24:21 AM
I have the water pump off my car and decided to check for timing chain slack. I can turn the crankshaft 9-10 degrees before my ignition rotor starts to move so obviously time to replace the chain and gears.
Doing a little research it looks like some people have had trouble with sealing up between the oil pan/ timing chain/ leaking. I have never done this before on an old engine. Any tips on doing this? The car ran great before I pulled it apart.... Will this mess up my timing? Any help here is appreciated. Thanks in advance.
Title: Re: Timing chain replacement
Post by: Rich G. on July 01, 2021, 02:04:51 PM
I don't think that's a big deal. New one will probably stretch anyway. Last few I did were loose right out of the box. It's not a big deal to change it anyway. Use a good sealer between the pans and cover and you won't have a problem.
Title: Re: Timing chain replacement
Post by: xx88man on July 01, 2021, 02:10:04 PM
I wondered that too.....how long before the new one is stretched that much too? 318 2bbl BTW
Title: Re: Timing chain replacement
Post by: Purepony on July 01, 2021, 02:58:17 PM
I just added the oil slinger on my 383 ans the chain was good so I left it on. I would recommend taking your time with that job and torquing everything to specs.  I did add a new timing cover just for safe measure.
Title: Re: Timing chain replacement
Post by: chargerdon on July 02, 2021, 04:51:39 PM
"The Right Stuff" while expensive seals just about anything.   I used it on my 360 LA engine when i swapped camshafts. 

On the small block if found that the oil pan gasket always tears off when removing the timing chain cover.   They include little pieces of gasket to replace the part that breaks off, but, i found that it was tough getting the timing chain cover on over top of that...   so instead of using those small pieces, i just filled it up with "the right stuff" and no leaks !!

Never did it on a big block. 
Title: Re: Timing chain replacement
Post by: Chryco Psycho on July 02, 2021, 07:50:58 PM
I would swap it out , the original is likely a nylon gear on the cam which is causing the slack , a double roller wiith steel gears would be my choice .
I agree Right stuff in the corner should seal it up no problem .
Title: Re: Timing chain replacement
Post by: Rich G. on July 03, 2021, 04:42:36 AM
I didn't think Mopar used a nylon gear . Thought that was a Pontiac thing. I replaced a bunch of them.
Title: Re: Timing chain replacement
Post by: Huskidrive on July 03, 2021, 05:08:59 AM
I remember the nylon on the chain was a cure for chain noise back in the day. My car had it. (1970 383) When I tore my engine apart in 2016 the pick up was full of nylon. I was surprised I had any oil pressure at all much less normal pressure. The rest of the engine was spotless even with about 75,000 miles on it......
Title: Re: Timing chain replacement
Post by: xx88man on July 03, 2021, 01:42:28 PM
I am replacing it. Ready to remove the balancer now. So when my spark plug rotor points to the #1 position the timing mark is a few degrees before 0. Do I want the timing mark at zero before I pull this apart? Or close is close enough? Or do I need a piston stop to find true TDC? Any help is appreciated here. Thanks
Title: Re: Timing chain replacement
Post by: xx88man on July 03, 2021, 01:43:34 PM
@Chryco Psycho (https://forum.e-bodies.org/mlist/chryco-psycho_4)
Title: Re: Timing chain replacement
Post by: Chryco Psycho on July 03, 2021, 05:38:10 PM
You need a piston stop If you are degreeing the cam which I always do when replacing a cam , for a simple chain replacement you can just line up the dots on the crank & cam gear & go .
Low performance engines used nylon cam gears , high perf used double roller or at least metal cam gears , I bet the 318 has a nylon cam gear thus the slack in the chain .
Title: Re: Timing chain replacement
Post by: xx88man on July 04, 2021, 08:50:40 AM
Quote from: Chryco Psycho on July 03, 2021, 05:38:10 PM
You need a piston stop If you are degreeing the cam which I always do when replacing a cam , for a simple chain replacement you can just line up the dots on the crank & cam gear & go .
Low performance engines used nylon cam gears , high perf used double roller or at least metal cam gears , I bet the 318 has a nylon cam gear thus the slack in the chain .

Thanks CP
Title: Re: Timing chain replacement
Post by: Chryco Psycho on July 04, 2021, 10:29:23 AM
 :bradsthumb: