Does it make sense to replace just the timing chain guides or not worth it?
Dec 6, 2016 | 01:41 PM
#1
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Does it make sense to replace just the timing chain guides or not worth it?
Hey guys, I have a '85 2wd 170k miles nothing-special edition. The previous owner replaced the head gasket but I suspect he didn't do a great job at it and didn't do any other work like the top-end refresh, water pump, timing chain etc. The oil gets dirty and thin extremely quick too, not sure if that's because it's running rich. Anyway, I'm also getting a slight rattle noise around 2k RPM so based on the info I've found it's likely the timing chain guides. Does it make sense for me to replace just the timing chain guides at this time and then when I have more time, hopefully end of next year, I can rebuild the motor or perhaps get a used one?
Dec 6, 2016 | 02:05 PM
#2
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From: Southern Arizona
No, worn, or broken guides are only the symptom, not the problem.
The problem is that the chain is worn and stretched, thus wearing the guide excessively.
If you disassemble enough to replace the guides, the chain and sprockets are in reach as well.
If you open it up, replace chain, sprockets, guides and all. These parts are cheap.
If you anticipate a complete overhaul in the forseeable future, I'd keep running it as it is, while keeping a close eye on oil and coolant levels, an engine operating temps.
Address the rich running condition, diluted oil will kill any engine fast.
Good luck!!
The problem is that the chain is worn and stretched, thus wearing the guide excessively.
If you disassemble enough to replace the guides, the chain and sprockets are in reach as well.
If you open it up, replace chain, sprockets, guides and all. These parts are cheap.
If you anticipate a complete overhaul in the forseeable future, I'd keep running it as it is, while keeping a close eye on oil and coolant levels, an engine operating temps.
Address the rich running condition, diluted oil will kill any engine fast.
Good luck!!
Last edited by millball; Dec 6, 2016 at 02:07 PM.
Dec 6, 2016 | 02:25 PM
#3
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From: Portland, Oregon, USA
X2 What millball said.
The timing chain guides hold up just fine with a good chain. They only usually become a problem after the chain has worn beyond what the tensioner can take up.
Technically, timing chains don't stretch. The pivot points in each of the chain links wears out, and if you add up all of the extra clearance in each link, you get a longer chain (it looks like the chain stretches because it gets longer).
I would definitely figure out your oil problem soon.
The timing chain guides hold up just fine with a good chain. They only usually become a problem after the chain has worn beyond what the tensioner can take up.
Technically, timing chains don't stretch. The pivot points in each of the chain links wears out, and if you add up all of the extra clearance in each link, you get a longer chain (it looks like the chain stretches because it gets longer).
I would definitely figure out your oil problem soon.
Dec 6, 2016 | 04:40 PM
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You read my mind w/ this thread. Keep us posted on what you decided to do. I am in the same boat as you. She is running good but I suspect the guy before me didn't do much work and always keeps me wondering.
Thanks guys for that input!
Thanks guys for that input!
Dec 9, 2016 | 10:46 AM
#6
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From: Northern AZ
FWIW, don't forget to check the timing cover for damage from the "stretched" chain rubbing against the cover.
If the cover wears through water can leak into the oil.
My 22r had that problem and for $20 got the old cover welded up to stop the leak.
If the cover wears through water can leak into the oil.
My 22r had that problem and for $20 got the old cover welded up to stop the leak.
