Sumps

Post by **LordAnthony** » Tue May 05, 2009 4:39 pm

Hello,

I have a few sump-y questions that I'm hoping someone can help with. Excuse my ignorance on these things but I've never had a car on which you have to do these things before! It's a 1958 2 door 1000 saloon by the way.

Ok -

Question 1:
Does anyone know if the 948 and 1098 have different sumps?
I've just taken mine off and tried to put a replacement one on but the semi-circular cut-out on the rear of the sump is not as deep on the replacement one and subsequently won't fit.

Question 2:
Is there a way to identify the engine size?
I was told that I had a 948 engine, but I'm not so sure because of the ill-fitting sump and also we had to replace the ring gear a couple of weeks ago and the one for the 948 didn't fit.

And finally,

Question 3:

my car leaks ("leak" doesn't quite convey the scale of it) oil when the engine is warm. It looks like it's coming from a square plate underneath the sump but when it's cold it's nowhere near as bad. When I took the sump off I filled it with water to see if it was leaking and nothing came out.
Is it likely that the heat is causing a gap to appear?

Many thanks,

Ian

Post by **mike.perry** » Tue May 05, 2009 6:14 pm

The 948 engine should have an engine no. starting with 9, the 1098 starts with 10MA. The back plates are different , the 948 is thinner and is turned over around the edge, the 1098 has a much thicker solid plate. Can't remember if the sumps are the same or not.

Post by **MarkyB** » Tue May 05, 2009 6:34 pm

There are no square plates on a standard 1098 sump.
How has it been attached?
Is there damage inside above the patch?

Post by **LordAnthony** » Tue May 05, 2009 6:48 pm

Mike - thanks for that I'll take a look.
Marky - It's been spot welded or something like that. There's no damage above the plate by the looks of things but I can't think where else the oil could be coming from,.

There are also little collars attached in a similar way on either side of each of the semi-circular bits where the cork seal goes but the one that doesn't fit doesn't have these or the plate underneath.

The oil is mainly dripping off around the plate but that could just be where it gathers.

Cheers,

Ian

Post by **PSL184** » Tue May 05, 2009 6:54 pm

If the engine number is missing a 948 block has "950" cast into the block beneath the exhaust manifold.... Your car would originally had a 948 in although this could have been changed. If the 948 ring gear didn't fit it is possible that a 1098 gearbox has also been fitted at some time in the past - again, not uncommon.

Post by **Mogwai** » Tue May 05, 2009 8:33 pm

you haven't got a 1275 have you? as the sump on mine has the remains of a square stiffener plate that that attached to the gearbox as used on the marina/ital

Post by **bmcecosse** » Tue May 05, 2009 9:47 pm

Definitely sounds like a 1275 engine - which has larger main bearings and therefore a larger sump to suit - and the Marina version has that 'square plate' on the rear edge (used to reinforce engine/gearbox join in Marina) . Does the engine have any cam follower covers under the manifolds - or is the block just 'solid' there?

Post by **LordAnthony** » Wed May 06, 2009 10:02 am

Well I never.
I've uploaded some photos which should be a lot easier than describing.
http://www.23hq.com/lordanthony/album/4299977
If it is a 1275 then I've fitted the wrong gasket to it which may explain the leak...

Post by **bmcecosse** » Wed May 06, 2009 10:24 am

Yes - it's a 1275 engine - well done ! Be sure to tell DVLA and your insurance company. What gasket did you change ?
Would go much better if you fitted the correct larger carb for a 1275 engine !

Post by **PSL184** » Wed May 06, 2009 10:30 am

bmcecosse wrote:Yes - it's a 1275 engine - well done !

From a Midget and not a Marina / Ital. Also, its got a 1098 box fitted. So, clutch, flywheel and ring gear etc will be 1098 also.

Post by **LordAnthony** » Wed May 06, 2009 10:34 am

That's made me smile!
It was the sump gasket that I changed.
Would fitting a larger carb bring any benefits other than speed?
Thanks for everyone's help.

Post by **bmcecosse** » Wed May 06, 2009 10:37 am

General improvement in acceleration and top speed. Your present set-up may give the best economy - so if happy enough with the performance just leave it be !
I agree it's a Midget engine (no screw-on filter) I would think that sump is from a Marina/Ital. Fairly sure the Midget sump was just plain with no 'plate'.

Post by **PSL184** » Wed May 06, 2009 10:38 am

There is no reason why you can't run it on that carb, as you say, it will just be slower. Also, its not really breathing properly due to the standard manifolds and exhaust system. You will notice much better performance if you fit an HIF44, separate inlet, freeflow exhaust manifold and a larger bore exhaust system - Should only cost you about £250

Post by **LordAnthony** » Wed May 06, 2009 10:54 am

To be honest I get a bit nervous when I go over 60 in it anyway!
I've just ordered a 1275 sump gasket and I'll see if that stops the leak.
Onwards and upwards...

Post by **Declan_Burns** » Wed May 06, 2009 11:52 am

If you have to replace the sump gaskets, I would recommend using the synthetic rubber seals instead of the cork seals that are sometimes supplied. This worked for me as I tried cork several times without success. As a precaution i thoroughly cleaned and degreased all surfaces and used high temperature silicone sealant allround allowing it to cure properly before starting the engine. I used the 1275 rubber seals cut down on my 1098cc. It worked perfectly.

Post by **PSL184** » Wed May 06, 2009 11:59 am

A trick with cork gaskets, which has always worked for me, is to soak them in water first so they swell up. Fit them into the groove with a smear of grease to hold them in position and then when you trim them off leave about 1/4" standing proud either side of the ends of the groove. When you then tighten the sump this pushes the soft cork firmly into the groove and seals it. By the time the water has dried off the oil from the sump has soaked in and provides a tight seal.

Post by **Declan_Burns** » Wed May 06, 2009 12:09 pm

I would also consider replacing that thermostat housing with a pre 1967 MGB housing. It only needs one of the mounting holes dressed with a file and has the right angle. Less stress on the top hose.

Post by **mike.perry** » Wed May 06, 2009 11:33 pm

It is important with a 1275 engine to get the crankcase ventilation system set up properly or it will leak oil from the back of the engine.
You should have a canister on the front of the timing chain cover which is connected by a length of hose to either an inlet pipe on the carb. or a breather control valve which is connected to the inlet manifold. The purpose is to suck the air pressure from the sump as it cannot escape past the push rods as it does on the smaller engines
I have been trying to download a diagram but it keeps screwing up and I lose my entry and have to retype so I'll send this and try separately

Post by **PSL184** » Wed May 06, 2009 11:39 pm

Can't see a canister on the pictures but it has got the rocker cover breather fitted....

Post by **LordAnthony** » Wed May 06, 2009 11:49 pm

There's no canister on there.
When I got the moggy there wasn't a breather connected to the rocker cover and the oil cap didn't have a seal but since I've sorted these out the oil leak seems to have got worse. I thought it was coincidence but could there be a connection?