running in

Post by **aupickup** » Sat Jul 26, 2008 6:35 pm

ok so have now replaced all main and big end bearings on my engine

so do i have to run it in, if so what oil and what is the best procedure

Post by **bmcecosse** » Sat Jul 26, 2008 8:02 pm

Just RUN it ! And 20W50 oil as normal. Bearings need no running in - it's the rings/bores on new engines that need a bit of care.

Post by **aupickup** » Sat Jul 26, 2008 8:25 pm

Post by **Dominic** » Mon Jul 28, 2008 6:59 pm

Just RUN it ! And 20W50 oil as normal. Bearings need no running in - it's the rings/bores on new engines that need a bit of care.

I'd personally limit it to about 60mph for a few thousand miles, and then change the oil again. I noticed a marked improvement in running, "zippiness"" etc after my new engine had done about 6000 miles. Faulty new main bearings were replaced after 2000 miles. Now it goes like a dream! (At least it will when I've finished rebuilding the braking system, rear suspension etc!)

Post by **bmcecosse** » Tue Jul 29, 2008 10:38 am

Yes - that's when new rings/pistons/bores - bearings need NO running in!

Post by **superchargedfool** » Tue Jul 29, 2008 10:41 am

bmc is correct if only bearings it makes no difference.

either way though use 20/50 as normal and change it early.

If had rings or pistons then yes run it in properly which is still normal oil, 1000 miles driving sensible avoiding using full throttle or high revs then change oil and enjoy it.