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MG MGB Technical - looking for a replacement engine

I am suffering with an engine which delights in using oil excessively and the 2 rear plugs are oiling up badly to prove the point. The oil pressure is 55psi when hot. I start creating blue smoke when the engine reaches working temperature. Have covered 150,00 miles, the car was laid up for 7 tears before it came into my possession. Anyone out there know of a replacement engine located near East Sussex? or the answer to my high oil consumption?
si robathan

The first thing to determine is where all the oil is going. How much is being leaked out and how much is being burned, probably through bad valve seals and valve guides on cylinders three and four.

The next thing to determine is what engine you need. That varied by year and you do not list the year of your vehicle.

The third thing to determine is what you mean by a "replacement engine". Are you looking for a good used engine to drop in? If so, when did the B series engine go out of production? How old would the newest engines be? (Here in the US, 1980 was the last year of importation.) Are you looking for a good, quality rebuilt engine? One which would last you a number of years as a daily driver, perhaps the rest of your life as a pleasure use only vehicle? If the latter, you might want to make contact with Chris Betson of Octarine Services. He posts here, from time to time, including some recent ones. I have found his service on parts to be excellent. Others have installed (or had him install) his rebuilt engines and have posted about how happy they were with the quality and performance.

Define what you are looking for, how much you can afford to spend, and how long you intend to keep the car. I tend to keep my cars for many years and money spent on quality parts is not the issue over a twenty plus year use that it might be if you are planning on selling the car soon.

Les
Les Bengtson

As Les mentioned, the model year of yours would be helpful. MGB engines are quite easy to overhaul and you don't even need an MGB mechanic to do so. The blocks, crankshafts and cylinder heads were meant to last a long time. A valve job is definitely needed per your symptons and that might be enough. However, if you have 150,000 on it (kilometers, I assume), your best choice is a complete overhaul. Buying a used engine can cause headaches if you get an engine too much different from your original. Also, rebuilding equals authenticity and matching numbers for you and future buyers (if yours is indeed the original). I assume you mean 150,000 kilometers on the engine in which case you're likely to get by with minimal machine work and not have to rebore and replace pistons. Although, that's still not that expensive.
Rick Penland

Thanks for the help Les and Rick, Yes I should have mentioned the year which is 1978 bgt 5 bearing crankshaft model.
Since putting out the request I have located an engine which has only covered 70,000 miles so I am going for this which I hope will go a long way to solving my problems.
I did a lot of thinking on how I should proceed but my present engine has covered 150000 (miles not Km's) and has been stored for seven years. Using lots of oil and also leaking badly has brought me to the conclusion a replacement is necessary.
I will post you on how I get on.
Regards
Stuart
si robathan

Stuart. It is not always the amount of miles an engine has on it. Frequently, how it has been used and maintained is more important. Since you have a running engine and have located a replacement, it might be worth considering a mini rebuild before installing the replacement engine. New rod and main bearings, have the cylinder head converted to run on unleaded petrol (which includes a valve job) and replacing gaskets and seals which, by this time, are often old, dried out, and do not do a great job of sealing. One thing to have checked out is the cylinder head. The majority of them I have seen have been cracked. If you are going to go to the trouble of removing and replacing an engine, you might want to ensure that the replacement engine will not have the same problems you are experiencing with your current engine.

Les
Les Bengtson

Do a compression test to evaluate valves and rings.
Art Pearse

When does it smoke? If all the time it could be rings and bores, but if only on accelerating after idling or a period on the overrun it could just be valve stems, guides and seals. There again it could be neither, but excessive oil being transferred via the crankcase breather system, just the rear two plugs being affected because the port to the front carb is blocked.

I agree, do a compression check (hot, all plugs out, throttle wedged wide open), and drive it for a while with the Y-adapter disconnected from the carbs and the carb ports sealed and see what the smoke and oil consumption is like then.
P Hunt

thanks for all our comments, I finally took the decision to replace the engine.I located one with 73,000 miles on the clock and warranted for 3 months.
My mechanic did a first rate job in doing the exchange. I now have a nice runner and a fair number of spares ie. alternator, twin carbs, distributor. Many thanks for all your advice.

Stuart
si robathan

This thread was discussed between 13/07/2010 and 06/08/2010

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