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bad engine

hi, My 91 740 has lost compression in number 4 cyl, problems started when I parked the car and came back hours later, wouldnt start, it started up the next day.Mechanic changed plug,wire, cap and rotor. He thought bad coil, not, replaced timing belt, because when it did start, it didnt seem to fire right and than he ran a compression test and said that the # 4 cylinder has no compression. The mechanic is a friend, I know he is not trying to make more money on me. I don't know if I should pull the engine apart or just replace it.I have a 1989 240 with a good engine, but bad body, will a 240 engine swapp into a 740 car? Thank you guys, If anyone has any thoughts on my problem I would love to hear them. thank hardlabor

Reply to
hardl;abor
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Are the distributors both mounted on the rear of the cam, against the firewall?

Assuming both are normally aspirated, you should be fine.

But, having said that, why not swap heads, as opposed to engines?

Assuming that is that the compression loss is valve related (in the head).

It is a PITA to swap engines, and is easier to swap heads.

Reply to
Mr. V

The motors are identical, but you will have to swap some of the accessories around. The 240 motor will have a gear on the aux shaft to drive the block mounted distributor while the 740 motor probably will not, but you can ignore that and plug the hole or you can use a block mounted distributor on the 740, but the head mounted one will not fit on a 240.

I would pull the head on the bad motor first and see what happened, if it's just a burned valve it will be easier to replace that, but you will also need to find out why it burned, bad injector can cause that.

Reply to
James Sweet

Take the head off to have a look first, might only be a bad head gasket.

Greetings Niels

Reply to
Niels Bengaard

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