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BMC A-series: Oil in coolant

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L

Ladybug

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(Non-native speaker, my apologies for any errors)

The 948 cc A-series engine on my Austin a35 (completely rebuilt a couple of years ago) is leaking quite a bit of oil in to the coolant. No sign of leakage occurring the other way tho. I've only been able to find detailed instructions on trouble-shooting and fixing the issue on BMC's C-series engines.

Any advice or links on the matter are greatly appreciated 🚗
 
Look at it this way higher pressure wins. your coolant pressure is between 9 and 12 pounds from Radiator cap, Right.
Your motor cyl. pressure at near new is over 100 pounds so it is pushing the block pressure to water jacket. Retorque head in the right order twice hot and cold. I would not think crack block but head gasket, there are a few spots where the material is thin between cyl and water jacket that would be the worse case. MF
 
The 948 is the same engine used in the Morris Minor and the Sprites and Midgets. There is a huge amount of information available online. It is always worth a try retorquing it, but if that doesn’t fix it, you will be removing the head.
Since the engine has been apart in the past, the head studs may need to be replaced and your head needs to be checked to make sure that it is flat.

Good luck getting it repaired.

I really miss my A35 van, but had to sell it and my ‘67 Cooper S to pay for childcare when I was in school. At least I was able to keep the Sprite!
 
Thank you both. I did notice this was a frequent topic on MG forums, but wasn't aware that midget had the same engine.
 
The above is correct as to head studs a small cost but smart money tighten more than three times that you know of. Only a light dressing of head is needed to make sure it is flat and true. and yes used on many cars. MF Where is Tampere
 
Madflyer said:
Where is Tampere
Click to expand...
Finland :smile:

After retorque and thoroughly rinsing the radiator, there seems to be much less oil. We'll be taking the engine out and reassembling anyway come winter. Might not be worth the effort tho - seems to be more of a feature than a flaw 😁
 
These motors are built for wear and tare and worth the rebuild. And yes they leak, a good look and inspection and careful reassemble will bee good for many years. This Forum as a guide as a tool also. MF
 
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