M42 Headgasket change or engine swap?

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cee
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Post Fri Jan 04, 2013 10:50 pm

I have been offered a potential px on my busted engine (head gasket blown) for another M42.

Assuming that cost wise it is feasible, would it be easier to swap the engine, or strip and fix the current engine? I'm getting conflicting views from everyone I ask.
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1990 Sterlingsilber 318iS - 146 bhp / 192 Nm
cee
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Post Wed Jan 30, 2013 4:32 pm

Okay so the deal is long gone as no one replied, but It's still a possibility to buy an engine. As above, would it be easier to swap the engine, or strip and fix the current engine?
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sunnysr
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Post Wed Jan 30, 2013 6:19 pm

i would just go for the swap you should be able to get a m42 for next to nowt and its a very easy swap , i have just took one out and put another in + swapping the gearboxes and some ancillaries over on an m20 in around 6 hours on a friday night and im no expert by a long way ,then if you feel the need do the head gasket on the spare motor and sell it if its worth it
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Brianmoooore
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Post Wed Jan 30, 2013 7:35 pm

Question didn't get answered because in an unanswerable question.
Depends on the condition of your existing engine, pre gasket failure and the condition of the engine you want to swap in. Bit silly swapping out a well maintained low miler, and swapping in one with 300,000 miles on it and oil like tar. Alternatively, if your engine is on its last legs anyway, and the swapper is a known good unit, then the swap is viable.
Another thing to consider is your facilities. A gasket change is almost all done from the top of the engine bay, with the heaviest thing you need to lift being the head itself. An engine swap requires a considerable amount of work under the car, which ideally requires the use of a ramp, or good axle stands at least, and a crane is required to lift the engines in and out.
cee
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Post Thu Jan 31, 2013 12:02 am

Valid point. I didn't think of it in that much depth. Thanks.

My main concern was that once opened up, the existing engine (160k) would require a lot of work to get built back up again. I guess the best bet here would be to strip it and have a look first.
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1990 Sterlingsilber 318iS - 146 bhp / 192 Nm
Andyboy
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Post Fri Feb 01, 2013 8:28 am

This has been going on for months now hasn't it?
cee
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Post Fri Feb 01, 2013 11:41 am

The headgasket went back in the summer and I've been messing around with it since. I do however need to get it fixed soon as it's just sat in a barn rotting.
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1990 Sterlingsilber 318iS - 146 bhp / 192 Nm