I would sure welcome some guidance. The car is at a used car lot, so I doubt I can trust any information I get offered about its history.

Other than blowing smoke, what are clues that the turbo might be about to fail? Whining? Oily tailpipe? Excessive boost lag--and would this be clear from watching the boost gauge, or just by feel?

I have a couple of 240s (one stick, one auto), so I am generally familiar with the drive train. But I don't claim to know beans about turbos. I did read the FAQ on turbos, but there's nothing like personal experience.

If I see water lines, can I assume the turbo has been replaced, or were the factory units water cooled in 1991?

Were all turbos on 1991s the same, or is there a version I should avoid?

Thanks for any help you can provide.

Doug Harvey

In this case, it would be beneficial on your part to have the car inspected by another mechanic. Pay for the 1/2 hour or so of lift time needed to make an inspection and write up the findings. Maybe it'll be an hour. Either way, $$ well spent. If the car truly has issues, they'll turn up. As you surmise, the turbo is the big unknown in this car's history, and is probably the single most expensive part of the car. Definitely in the top-5. A good checkover from below is needed to identify oil leaks from the turbo lines or oil filter housing, both common trouble spots, as well as a good visual check of the special water hoses. This will also let you know about regular RWD Volvo problems, like a bad tailshaft seal, center bearing, pinion seal, exhaust leaks, rear main seal, suspension bushings, et cetera....
The turbos are all watercooled in 1991, and it will be a Mitsubishi turbo, the better of the two types Volvo used (easier replacement too!)
Key things to remember are that the turbo's cooling system works much harder, and therefore the radiator must be perfect, and likewise the water pump and heater control valve. Any leaks *MUST* be addressed immediately - you risk head gasket damage if the car overheats. Also, the large air intake hoses need close inspection. If the turbo does leak oil, and they all do eventually, oil attacks the hoses and rots the rubber. Then you've got a vacuum leak and all sorts of running problems, including copious amounts of black smoke. Make sure this is part of the inspection. Finally, the front rotors on all 740's are subject to warping. Assuming the car exhibits shakes when braking from speed, use that as a bargaining chip for price- new rotors list at $97 from Volvo each, and maybe 1/2 that through mail order. Not acceptable to turn the rotors- they are thin enough when new.
So make some notes, have a shop that services Volvos check it out, get the best deal, and add it to the collection. Good luck!
--
Rob Bareiss, New London CT ::: 86 244DL, 87 244DL, 88 744GLE, 91 244: 808K total

The turbo will not definitely be a mitsu. The Garrett T25 was also used on the 91 turbo models; my 91 744T has a T25. To check the turbo, spin the shaft inside the housing. If it spins freely and doesn't have any play going back and forth or left and right, it should be in fine shape. If the car has been running synthetic oil, that is always a plus. Good luck.

Roguls
New York, USA

Always have a third party mechanic look over any used automobile and give you his analysis. An experienced indy volvo guy can tell many things about the car based on very minute data that you would probably miss. Compression test, coolant system and pressure test, transmission, exhaust, etc. Any good mechanic should have a standard fee for such a job. If the used car dealer won't allow you to do so then walk away.

As for the turbo, I would do three things:

1) Get a paper cup, go under the front bumper, and undo the drain cap for the intercooler. Place the cup under teh cap and collect any oil that drains out. If you get much more than 2-3 tablespoons that's a bad sign (turbo is throwing oil). If you get nothing that may also be a bad sign since its likely the dealer cleaned out the intercooler (as service or cover, who knows).

2) Pull the hose off the front of the turbo and check for play. Take a look in the FAQ for more info on how much play you should see, etc. Some small lateral play is fine, but anything substantial is a problem.

3) Inspect the turbo physically, peeking around the sides and from teh underside if possible. Make sure you don't see any oil leaks. You also might look at the hoses and make sure there aren't any holes in the bottoms (the main tubro hose is pricey).

good luck,
rt

Carfax isn't perfect but at least you can see a title history. This will tell you where the car was initially sold and where it's been licensed. From there you might be able to contact the dealer and with the VIN get a copy of the service history if it was dealer serviced. See my post for my story on findint information on and purchasing a 740 turbo at:

http://www.brickboard.com/RWD/index.htm?id=582461

Armed with the information I got on the car, and the relatively low amount of money involved, I felt comfortable buying then driving. That said, if this car is near you and you can't get any service or ownership history, it might be prudent to have an independent Volvo shop go over it and give you a "Buy/Nobuy" recommendation. What's the mileage?

--
Erwin in Memphis, '95 855t