Hi folks
Am contemplating purchasing a 740 turbo. '86 model, 233,000km (150,000miles). Have looked through the excellent 7XX/9XX FAQ, but am wondering if anyone had ideas about any other things of note to be on the lookout for.
It has a good history with recent receipts for work done (including new fuel pump, almost full exhaust, and a bunch of other minor stuff), so p.o. wasn't averse to spending a buck on it. One thing which worries me is that it has the engine replaced with a low mileage used one a year ago. Seems very healthy though.
Only problems I could find are: 1) Auto gearbox a bit tardy about the 2 - 3 change but otherwise faultless 2)It seems to be a bit down on boost/power, but that might be due to a combination of crap fuel and/or wastegate adjustment (?) and 3) the aircon compressor is missing (I have a good rotary compressor so that probably isn't a najor problem). A few other niggly things like non-functioning rear window motor, ticking from ventilation blower, etc. Body is spotless and unmarked, interior a "used"; headlining sagging, some split seams in the seats, odd bits of loose plastic trim here and there. Drives well.
All suggestions and advice will be gratefully received.
Oh, and I hope it doesn't appear rude if I don't get back here for a day or so. Unavoidable at the moment.
Thanks guys
--
Steve. Certified nutcase and bon vivant

Steve:

My 86 turbo has 163K miles too. I bought it four years ago from a small local car lot. The body was (and is) still excellent and rust-free. It has a few cracks in the top of the dashboard, but that's minor.

1. I noticed a ticking sound about 2K miles ago. Turned out to be exhaust manifold gaskets.
2. I agree with the other postings regarding rust along the door seals and in the trunk.
3. Check for loose wheel bearings; these should have already been replaced, but jack up the wheels and wiggle them top and bottom for play.
4. Timing belts have about a 40K mile life. Don't want to break one and bend all your valves.
5. Heater cores tend to go about this time.
6. Make sure the catalytic converter isn't plugged. That can be a source of lost power.
7. I use 93 octane religiously. We can't get 91 around Chicago-our choices are 87, 89 and 93.
8. You might pull the intercooler to see if it has any oil. Loosen the two big hose clamps on either side and take off the top mounting brackets and it will lift right out. Take out the drain plug on the bottom (be careful, it's plastic). Setting it in the sun for a short time helps any oil drain faster.

Good luck and let us know what you find.
--
Steve Arnold near Chicago, 1986 740 Turbo, 163K miles

check to be sure the tamper seal on the wastegate is still there, if it is, you know it wasn't turned into a hot rod.

Will check out a bunch of stuff you mentioned.
--
Steve. Certified nutcase and bon vivant

Steve,

Here's some items to check for:

1. Rust at driver's and passenger's floor. Best to pull up the carpet and check. Caused by water leaks.
2. Burning oil from turbo. Have someone else drive it and follow from behind in another car and look for oil smoke. Also a good time to check for "dog tracking" i.e. rear end does not follow front.
3. Rust in trunk at sides or at bottom of spare tire well. Also look underneath door seals on doors, as well as the bottom.
4. Tranny rear seal/bushing. Is the tranny fluid low? Look underneath; Is the undercoating on the body around the tranny output shaft all sticky and melted from Dexron III spewing everywhere?
5. Look at the fusebox and check for melted plastic around contacts underneath relays and at fuses.
6. Front control arm stay bushings.
7. Does the odometer work? trip od too? Also make sure all the idiot lights work.
8. Check turn signal lenses and see if any are about to fall off.
9. Does it still have the plastic radiator. A car this age should have already had the coolant hoses, radiator, heater valve and reservoir replaced.{in a perfect world!!}
10 How bad is the oil leak at the oil cooler? The oil filter adapter?
11. signs of past wrecks, ie new glass, paint on window seals, misaligned body panels, etc. ( you probably already know this!)

These are just a few things I could think of that you could perform fairly easily. Some are likely redundant, if you've read the FAQ too.
HTH
Bob Agle

turbos have an average life of 160k miles, so the turbo on the car you are looking at "may" be approaching its end. This may or may not be the reason for the weak performance you mention. Of course, performance in these cars can be affected by octane as well... I used 87 once and thought I'd killed the turbo or something (it just wouldn't accelerate properly). Changed back to super (91-93) and all was right as rain.

engine harness deterioration. especially prevalent on earlier models with "green" ecowiring (yesk the 1986 is included in that group) and PARTICULARLY on turbos with the high heat.

has the car had transmission work previously? gears can get sticky with age on the manual (especially 1st), but its usually the early harbinger of the death sprial. Of course, that spiral can take 30k-40k miles with proper care, so...

and of course check the undercarriage for any rust or corrosion, with particular attntion to the drains in the doors (bottom), the drains along the body under the door jams, the front of the driver and passenger floorboards, and the bottom or the rear storage compartments.

good luck with your purchase.

-rt