4.0 liter main bearing clearance?

mgbv8542 · Post by **mgbv8542** » Mon Jul 07, 2008 11:11 pm

we are rebuilding a Rover 4.0 and have a question. The main bearing clearances are .002 with the exception of the #1 (from the front of the engine) bearing which is .003. From what I understand that is the maximum allowed. So my question is with that one bearing having that amount of clearance, will it be a problem? I would prefer not to have to regrind the crankshaft if possible.

RoverP6B · Post by **RoverP6B** » Tue Jul 08, 2008 8:38 am

According to the Land Rover engine manual of 1997, the Main bearing diametrical clearance for the 4.0 is 0.0004" to 0.002".

Therefore, if your #1 is already 0.003", then that means that it is outside of the allowable range by 0.001".

Ron.

TVRleigh · Post by **TVRleigh** » Tue Jul 08, 2008 9:18 am

When I striped my 4.0 and fitted new shells it was very tight on the clearances (the other way i.e. nearly to tight) so if you have a large clearance then you must have had a lot of wear.

Boosted LS1 · Post by **Boosted LS1** » Tue Jul 08, 2008 7:31 pm

Have you tried fitting the bearings onto different journals ie, find the largest journal and fit the bearings there.