Bearing renewal?

[swampy42]

Earlier in this thread 'Les' said that a thicker oil should be used when re-assembling. I wont be using the engine for quite some time once re-assembled, so what oil is recommended, if it's going to be sat around for a few months, if not just the standard engine oil?

[alexmcguffie]

Graphogen has been around for years and is well regarded.

http://www.burtonpower.com/parts-by-cat ... -grap.html

[les]

Torco make the stuff I used, it's red in colour, not that that has much significance, it's very sticky and clings to surfaces. When engine oil circulates it dissolves but doesn't run off prior to that. Engine Assembly Lube. Actually mine came from Burton power as well.

[bmcecosse]

lashings of 20W50 is perfectly adequate - and crank the engine with plugs out to get pressure up before attempting to start it!

[les]

Ok if the engine is put into service right away, if not this stuff hangs about longer, can't be a bad thing!

[alexmcguffie]

It pays not to cut corners if you're going to the expense of rebuilding an engine. Graphogen leaves a permanent protective layer that is virtually impossible to wash off. I use it at work. You may not need it if you know you will run the engine the day after you rebuild it but it will help in the long run.

[swampy42]

Many thanks for those suggestions guys. Changing the thread slightly, I've read other threads about running your finger nail down the cylinder about quarter of an inch from the top and if you can feel a ridge, then it's time for new rings. Initially, visually there didn't seem to be a ridge, but on closer inspection (which I've just got around to doing) there is a ridge. OK, I guess new rings are needed, but is it as simple as that? Do I also need a re-bore? Could the ridge be down to accumulation of deposits above rather than wearing of the cylinder below? Confirmation that new rings are needed or that I don't know what I'm talking about would be appreciated.

Russ

[alexmcguffie]

Hi Swampy,
At the end of the day it comes down to your budget and how often you use the car. If low mileage then you could live with it as is or you could get it honed to take the step out and de-glaze the bores. The step sounds very very small from your description. You may or may not need new rings then though. If the engine is out of the car you'd be best to take it to a machine shop and have it measured up by them.

[bmcecosse]

It's all down to cost - and what you expect from the engine. If you want it to be 'new' then yes it needs a rebore/hone and new pistons.... If you are happy as it was - just clean up and re-assemble. Something in between - then gently smooth away the ridge and glaze bust the bore surface - and fit a new set of rings.

[swampy42]

Yep, I think that sounds like a plan. I've attached a pic of the cylinder just in case I'm missing a trick that a more experienced eye will see.[frame][/frame]

[alexmcguffie]

That doesn't look bad at all. Looks like it would Scotchbrite out

[swampy42]

Scotchbrite - now your talking my level of engineering.

[bmcecosse]

Hard to tell from one picture - frankly if it wasn't burning oil before I would probably be re-assembling it after a clean and a scuff -IF it's just a run-about engine.

[IslipMinor]

Swampy,

If you are anywhere near Oxford I have a glaze busting tool and can also measure the actual bore size as well.

[swampy42]

Richard
That's a kind offer. The only time I'll be going anywhere near Oxford is towards the end of this month when we have a wedding on. I'll put it to the lady wife!

[swampy42]

Richard
Went down like a lead balloon. Thanks for the offer though.

[swampy42]

Just had a chance to have a look at the top half of the main bearings and there's almost no sign of wear (no copper colour). Is it usual for there to be such a difference between the condition of top and bottom bearing shells? I've bought new shells so will replace them all anyway, but was just interested. Also, I've mentioned the piston ring condition previously, about how a small piece has broken off from one of the top rings. I assumed that the rings would be OK to reuse (if I replace this one broken ring), but I don't really know if they are. Is there a way of telling? Thanks as always
Russ

[bmcecosse]

When you realise that all the piston drive force is downwards - it's understandable that the main shells underneath take more wear. That is the reason why MG/Rover later changed the lower main shells to 'solid' design with no oil groove - initially on the Turbo engine - and then right across the range. So it seems to me with new shells all round -you will be 'good as new'. Have a look at the oil pump - and decide for yourself. The ring...as I said before was possibly broken when it was assembled many moons ago - I can't see a huge problem just re-using it, but if some kind soul will donate a ring from a used set that would be better. I would not buy a complete set of rings just for that!

[swampy42]

Am I missing something? Is there any reason the new set of bearings I've just bought are missing the hole and oil channels?

[bmcecosse]

They can't be the right bearings....where did you get them? Pictures??