Center Main Bearing Replacement

[TucsonRoverhauler]

Hello, All.

I'm fairly new to Rover ownership, having acquired a disassembled '63 IIA and a well worn '62 IIA. My local independent Land Rover mechanic is telling me that the rumble I get on the '62 at higher RPM is because the center main bearing is very worn and that I could get by for a while with just dropping the oil pan and replacing it.

Has anybody here been through an in situ replacement of the center main bearing? Are there any gotchas to doing this or is it a fairly straightforward repair?

[jimfoo]

The bearing replacement is easy. Use a plastic putty knife to push the upper half out, or if you are careful, you can bend a thin cotter pin into a sort of T shape, put it in the oil hole in the crank and turn the crank to remove/install the bearing half. The thing is if one is on it's way out, the rest may be as well. If the crank isn't perfectly smooth, you will need to pull it and get it re-ground and get oversized bearings.

[TucsonRoverhauler]

Okay, thanks. Since it's already hit 103F out here, I'm just looking to do the minimum to get through a summer of occasional 30 mile drives up to nearby trailheads with the dogs loaded in the back and a gal who seems to like me, or at least likes riding in a Land Rover, in the passenger seat. If I can, I'd like to hold off the engine rebuild until next October when it starts to cool down a bit. An engine rebuild now would probably have me undrivable for at least a few months, right when a Landie based relationship is starting to blossom. I've got more repair worries than just the engine. I need a new diff in the rear, the transmission leaks oil out the front, u-joints are shot, a wheel is broken, and a front hub bearing is worn. For now, I'm thinking I'll slap another used differential in, watch the oil level in the tranny, swap out the driveshafts for others I have from the restoration project, run the spare wheel in place of the broken one, and take care of the wheel bearing.

[zed]

is that the center main? sounds like you described replacing the rear main oil seal.

[TucsonRoverhauler]

I dropped the pan this morning. It looks like the oil pump has to be dropped to get to the center main. Anything I should look at with the pump as a reason why oil pressure drops in a turn?

[zed]

does it have a pressure relief bypass plug or something. I am unfamiliar with rover pumps. Stripped gear? Fracture?

[zed]

I'm starting to lose pressure going up hills... Curious..

[jimfoo]

I used to run mine a quart or so high to keep it from coming on going down steep hills. I never remember a problem on turns though.

[TucsonRoverhauler]

Okay, I got my replacement bearings from RDS last week and went out this morning to replace the center main. The new bearings don't fit. Arrrrrgh!!!

The new bearings are standard thickness, but are narrower, a slightly larger diameter, and have the tang on the wrong side. There's no way they'd work.

This being Sunday and no way to reach George, I've been googling for answers. The best info I can find is a listing for King bearings that show mechanical drawings appearing to match what RDS sent me. I can't find anything using the part number stamped on the back of the old bearings; 276857. I can't find anything using the 9761 number on the back of the new bearings either. Can anyone give me a bit of wisdom on this?

Also, I took the oil pump apart and found things in good order. I'm assuming my drop in oil pressure is because the center main was so worn it was just leaking oil like crazy.

[jimfoo]

I wonder if the '62 has a Ser II engine as they have different bearings, much harder to find.

[TucsonRoverhauler]

Please elaborate. Everything I find says the II had the 2.25 and there's no reference to there being different 2.25s in any parts catalogs or literature I'm seeing. I've even read that all NA II, IIa, and IIIs were shipped with the same 2.25.

Of course, I don't necessarily trust everything I read. If you know different, please tell me more.

[TucsonRoverhauler]

I talked to George this morning. It looks like I've got a IIa head on a II engine. Main bearings are $155 a set. Rod bearings are $60 each.

Phooey.

Anybody got a spare IIa short block sitting around they'd part with cheap?

[TerryS]

I do, but the freight from CT to AZ would be expensive. It was a bit smokey, but had good oil pressure. If you're going to do rings, you may as well do all the bearings, front and rear seal at the same time. (on this engine)

[jimfoo]

I've got one in CO, or my friend has a good running long block, head shaved to 9:1, 2.5 cam and 2bbl Weber. Mine had a blown head gasket. I had bought it along with a bunch of other parts from a guy who had sold his Rover. I never had it in the truck, just pulled the head, which is how it's been sitting for many years since. It would probably need to be cleaned well as who knows what's gotten into it, but I'd part with it for $50 + whatever shipping would be. Somehow I'd bet bearings are cheaper than shipping though. I have also heard there are places that can re-babbit old bearing shells, so that might be an option.

[TucsonRoverhauler]

For now, I'm going to run the old center bearing. I flipped them top to bottom and that seems to have helped a lot with the crankshaft rattle. After also replacing the rear diff and changing out the rear driveshaft, I finally got to motor around some last night night.

Woohoo!