Can anyone with fresh bearings/OEM clearances running 20W-50 tell me if they notice any pressure gain (and how much) when they let off the gas and the crank lifts at say, 2500 RPM?

6 VOLTS/POS. GRD. NW INDIANA

I went out for a drive tonight.  I'm not running oem clearances.  I am using 20w50.  The pressure does not gain when I lift.


Lawrenceville, GA

Dan,

      If you have an electric gauge, check your wiring.

Frank/Rebop

Bristol, In ( by Elkhart) 

Thanks guys;



Mechanical gauge only installed recently, so don't know how long problem has existed (7-8# crank-lift pressure gain). Should have mentioned bearings have at least 70K on them (could be 100K), but possibility of loose mains had not occurred to me (they WERE apart awhile back to change rear seal).

Just trying to get a handle on the situation, as it really kills me to have to tear down a fast motor that otherwise runs perfectly.

6 VOLTS/POS. GRD. NW INDIANA

Dan,

           If you have decent oil pressure and no noises..... drive it.

Frank/Rebop

Bristol, In ( by Elkhart) 

Frank;



Pressure still within acceptable range, and only knocking I ever heard was the one time I was dumb enough to forget to pre-fill the oil filter. Once you hear THAT sound, you never forget again!



All the little things you tend to put off because the short-block is tired (leaking front seal, weepy head gasket, etc.) can be lived with, though peace-of-mind might require dropping the pan to inspect the mains/bearings, or doing an oil analysis at least.

6 VOLTS/POS. GRD. NW INDIANA

Start saving your money for one of Mummerts stroker kits. 340" could be fun!! 

Frank/Rebop

Bristol, In ( by Elkhart) 

Yeah, I agree with Frank, if you still have good oil pressure and it's not making any rude noises keep driving it, you might get another 10,000 miles or X number of years before you have to do something with it, of course monitor it closely. It's only since you put the gauge in, nothing else has changed, before that it sounds like you where very happy with the performance of your engine.  

Pete, one of the Aussie mob. Beechworth, Victoria60 F100 Panel Van, Y-block. 65 Galaxie Country Sedan 390