Changing Main Bearings

Brian-Northampton said:

Richard - My "before" oil pressure readings were a good constant 60 PSI (judging by the dashboard guage), but once the oil was very hot after about 15 minutes of driving (say), then when the car was idling, the oil pressure dropped to 30-40 PSI.
Ouch, I would say that is a bit on the low side for these engines. Good chance you've caught it before the engine went pop. Mine went with 65k on the clock!

Mine is 50 at tick over, 60 above 2000rmp hot or cold (including ten mins in a traffic jam on a hot day). Only drops a very little with 6 month old oil.

Nice one. :)


Well-Known Member
Hi Brian
thanks for writing this up with the photos. You can show Haynes how it should be done! I may have to dothe same thing myself on my 2000tc this winter so it's reassuring to see it done by someone else who hasn't done this sort of thing before either.


How do you get such good photos of the underneath of your engine ? Do you hold the camera under the engine and hope for the best or have you special techniques ?
I've been for a test drive today and....... Hurrah!
Oil pressure is now in the 55-60 PSI band all the time, hot or cold ...... RESULT!
Of course the actual pressure is hard to gauge, but the lowest the needle drops to, is just covering the '0' of the '50'.
So, I'm really pleased.

Dave - I use my old Kodak CX7530 for the car - 'cos I don't care if my old one gets dirty! It has a setting for close ups which allows for close focussing. I also tend to take a couple and try to aim as best I can, after all, it's hard to look at the screen, and be a reasonable distance from the subject. So, a bit of guesswork. But with digital images, the wrong ones can just be deleted. I also put the flash on 'fill in' setting, so that it flashes regardless of the conditions.

Here's an interesting side effect of doing the job.

I made sure that (going by Harvey's recommendations) the sump was pulled in nice and tight against the bell housing before tightening up all the bolts.
My gear selection is now significantly smoother as a result!

Prior to doing this job, my gear selection was awful. All gears were a little stiff, but particularly 1st - which was out of alignment with 2nd.
Going from 2nd to 1st meant going into neutral, slightly to the right, then up into 1st.

I can only presume that this was as a result of a local garage doing the timing chains a few years ago, but this symptom came on gradually over time.

I noticed in the manual it does state that not putting the sump on correctly can mis-align the gearbox primary pinion. Mind you, what they wrote in the manual didn't make sense to me as it implies doing up the bolts on the sump before the bell housing bolts. As the bell housing bolts have to be tightened to 25 LB FT, I did the sump bots up lightly but not tight, then torqued the bell housing bolts, then tightened the sump bolts.

Seems to have worked!

I just did my bearings, and found this discussion to be invaluable. It gave me the confidence to tackle the job. I found that an old credit card, sliced down to size was good for pushing out the old upper main bearings. The old bearings were not too bad, but I feel better now that I have put new ones in.

Hi Brian,

Many thanks for such a good guide and Harvey for your top tips; I’ve just changed my big ends and mains and oil pressure now where it should be!

Best wishes

Who are Steve Walker and Richard Moon?
Are they members or retailers of rover parts.
I am after mains, big end and cam shells, and the current price from JRW is nearly £400