Hello,

I think the alternator in my '85 740Ti froze. I still have my old '84 240 GL, and its alternator worked flawlessly.

Can I switch 'em out? An alternator's an alternator, right? Or do I have to worry about any crazy electronic components in the 740? Someone told me something about the voltage regulator, and I understand that that's important to keep safe. Is it on the alternator, or what? Would I fry it if I switched 'em?

Thanks,

Volfro

PS: Now that I think about it, the 740 has a problem with 'blow-by', as my father calls it. Oil leaks out of the filler cap. Is there a way to fix that?

I replaced alternator on 85 740, with one from autozone.

The cost for the one for a 740 was about 150.00 the one for a 240 ran about 100.00, so I used the 240 one. It seems to work okay, although the voltage seems a little low 13.75 instead of about 14.25 or so I was getting.

jc

Volvo alternators hold up quite well, as a result there are plenty of good used ones around at reasonable prices.

I got my last used one for $30.
--
3 8s & 2 7s 725,000 miles total

Don't know about the alternator switch but your leaking oil cap could be caused by a clogged flame trap. Crankcase pressure isn't being allowed to vent. This could also lead to leaking seals. I'm new to the 4-cylinders, but I recall reading that depending on year, the flame trap is either above or beneath the intake manifold. It's inline with a hose from the oil separator on the side of the block.

Good luck,
--
Erwin in Memphis, '95 855t