When is it time to Rebuild?

from6to8

There's suction so I used that end O_O
15 Year Member
Sep 2, 2012
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How much does mileage solely have to do with it? I have 177 on it now and put 100k on motor since the swap in 02. When I did the cylinder balance test few months ago everything was fine. I'm just wondering as I remember people saying those 302's could go for 250-300k easily if kept up the maintenance. Then again I remember someone from a forum thinking that 177k was alot of miles so.....................?
 
All that matters is how its running.

If its running crappy, no power burning oil smoking out the rear, I'd say its time for a rebuild.

I'm at 230k, runs well doesn't smoke leak overheat and is not down on power.
Now would I like to rebuild it?
Sure!
Necessary?
Nope.

It all depends on your particular engine.
 
If it ain't broke, don't fix it.
If it starts smoking all the time, not just when you first start it, you might have to rebuild the heads, or have a slight chance of ring issues.
Excessive smoking from the crankcase is a sure sign of ring issues, but is hard to notice with the PCV system hooked up.
If you ever see your dipstick not fully seated, push it back into place, then see it unseated again after driving, that is a sign.

The biggies for knowing when the bottom end is out are:
Low oil pressure, or oil pressure that drops when the RPMs rise.
Compression testing that shows more than a 20% variance in results from one cylinder to the next, both wet and dry tests.
Bearing noises