wemay
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Others have posted different brands with the same looking varnish. Not an issue at all. Looks great.
284k mile 1999 Mustang GT 4.6l valve cover off
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It's apparent that after 284k miles, a light film of varnish doesn't hurt anything.,,
Originally Posted By: FowVay
I wish it had been run on 5W-20 instead of 5W-30. This might help (or hinder) the argument about the lower viscosity fluid being unable to protect the engine long term.
My daily driver is a Nissan OHC engine with 270,000 miles on it. It isn't in any better shape than this Mustang engine but it's still running just fine. I did do a timing chain at 250,000 miles because the chain guide was broken. The chain and sprockets were worn out.
I have a 97 f150 with 255k on it that has been run on 5w20 since 50k miles. It's still running well with no chain noise at all. The killer on this mustang engine was they overheated it multiple times. The guides and tensioners get brittle over time and excessive heat can crack them causing a failure. Whenever I tear one apart I always replace chains an guides regardless. I've seen dozens apart with high mileage and 5w20/30 doesn't matter at all. Personally I prefer 5w20 in them, however. This one was cleaner than most. The cleanest one I've had open was a 150k mile unit. It had a life of vwb 5w20 every 3-5k according to the owner. We replaced valve cover gaskets and intake gaskets on it. It was also in a 2001 truck so it likely had and easier life than a mustang GT typically does.
I wish it had been run on 5W-20 instead of 5W-30. This might help (or hinder) the argument about the lower viscosity fluid being unable to protect the engine long term.
My daily driver is a Nissan OHC engine with 270,000 miles on it. It isn't in any better shape than this Mustang engine but it's still running just fine. I did do a timing chain at 250,000 miles because the chain guide was broken. The chain and sprockets were worn out.
I have a 97 f150 with 255k on it that has been run on 5w20 since 50k miles. It's still running well with no chain noise at all. The killer on this mustang engine was they overheated it multiple times. The guides and tensioners get brittle over time and excessive heat can crack them causing a failure. Whenever I tear one apart I always replace chains an guides regardless. I've seen dozens apart with high mileage and 5w20/30 doesn't matter at all. Personally I prefer 5w20 in them, however. This one was cleaner than most. The cleanest one I've had open was a 150k mile unit. It had a life of vwb 5w20 every 3-5k according to the owner. We replaced valve cover gaskets and intake gaskets on it. It was also in a 2001 truck so it likely had and easier life than a mustang GT typically does.
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Originally Posted By: OVERKILL
Originally Posted By: aquariuscsm
From looking at this pic with my phone,it looks spotless! I don't see any varnish.
Should all be aluminum colored. It isn't. There is varnish. Not a lot, but it is there. Still, for the mileage, it looks pretty decent.
+1. However my old 96 Merc 4.6 had 218K when sold and the head was spotless for any varnish and that was with 10K OCIs.
Originally Posted By: aquariuscsm
From looking at this pic with my phone,it looks spotless! I don't see any varnish.
Should all be aluminum colored. It isn't. There is varnish. Not a lot, but it is there. Still, for the mileage, it looks pretty decent.
+1. However my old 96 Merc 4.6 had 218K when sold and the head was spotless for any varnish and that was with 10K OCIs.
Originally Posted By: Cujet
The heavier viscosity oil will extend chain and guide life in modular engines.
I would agree. With yards of chain flying around you will tear an oil up sooner. But IMO the guides are far more sensitive to heat cycles. And of course any slack in said chains...
The heavier viscosity oil will extend chain and guide life in modular engines.
I would agree. With yards of chain flying around you will tear an oil up sooner. But IMO the guides are far more sensitive to heat cycles. And of course any slack in said chains...
Originally Posted By: SteveSRT8
Originally Posted By: Cujet
The heavier viscosity oil will extend chain and guide life in modular engines.
I would agree. With yards of chain flying around you will tear an oil up sooner. But IMO the guides are far more sensitive to heat cycles. And of course any slack in said chains...
Also depends the oil used. I use 0-20 and have had no problems with chains or guides.
Originally Posted By: Cujet
The heavier viscosity oil will extend chain and guide life in modular engines.
I would agree. With yards of chain flying around you will tear an oil up sooner. But IMO the guides are far more sensitive to heat cycles. And of course any slack in said chains...
Also depends the oil used. I use 0-20 and have had no problems with chains or guides.
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