Originally Posted By: Wurlitzer
Originally Posted By: BrocLuno
The op temp viscosity depends on the bearing clearances. How worn is the engine? Somewhere around 100,000 miles with a carb'd engine is usually the turn over point. Reason is fuel dilution from rich starts and the associated wear over time.
302's are not known to cam/lifter failures. Any HDEO will be entirely adequate. 10w30 or 15w40 will be fine. Any ZDDP level over 800 PPM is fine for OEM valve gear. I'd take a bit more if availble ...
Can you find Mystik JT-8 locally at a good price (Tractor Supply?). It's a good oil for older engines
My fav is Delo 400 15w30 SD (severe duty), but it's hard to find and can be really pricey for some reason. Do you do any business with the Chevron Distributor?
There's no telling how many miles are on it. The odometer rolls over at 100k. Plus the headers were rebuilt at I don't know when. I don't even know exactly what the "headers rebuilt" actually means either.
OK, so for this engine we can assume it went far enough to need the Heads rebuilt ... That means a valve job, maybe a few new guides, check the springs and replace any below spec, etc. Prolly all stock ... But the bottom end is getting worn some. Say it has 150,000 miles. I'll bet the rod and main bearings are like 0.0035 or so ... So it will be happy on a XW-40 just fine. I'd use a conventional oil. But you can use whatever you want.
Do you know if they changed the timing chain? That's a biggee on 302's as they age. They'll stretch and retard the cam, so it'll be sluggish ...
At over 150K, a HV pump is a good idea as it moves more oil and will force some additional side leakage off the front main and the front cam bearing. That will keep the timing chain much happier
Originally Posted By: BrocLuno
The op temp viscosity depends on the bearing clearances. How worn is the engine? Somewhere around 100,000 miles with a carb'd engine is usually the turn over point. Reason is fuel dilution from rich starts and the associated wear over time.
302's are not known to cam/lifter failures. Any HDEO will be entirely adequate. 10w30 or 15w40 will be fine. Any ZDDP level over 800 PPM is fine for OEM valve gear. I'd take a bit more if availble ...
Can you find Mystik JT-8 locally at a good price (Tractor Supply?). It's a good oil for older engines
My fav is Delo 400 15w30 SD (severe duty), but it's hard to find and can be really pricey for some reason. Do you do any business with the Chevron Distributor?
There's no telling how many miles are on it. The odometer rolls over at 100k. Plus the headers were rebuilt at I don't know when. I don't even know exactly what the "headers rebuilt" actually means either.
OK, so for this engine we can assume it went far enough to need the Heads rebuilt ... That means a valve job, maybe a few new guides, check the springs and replace any below spec, etc. Prolly all stock ... But the bottom end is getting worn some. Say it has 150,000 miles. I'll bet the rod and main bearings are like 0.0035 or so ... So it will be happy on a XW-40 just fine. I'd use a conventional oil. But you can use whatever you want.
Do you know if they changed the timing chain? That's a biggee on 302's as they age. They'll stretch and retard the cam, so it'll be sluggish ...
At over 150K, a HV pump is a good idea as it moves more oil and will force some additional side leakage off the front main and the front cam bearing. That will keep the timing chain much happier