RIP My 240; Whats the skinny on 740s

They're mechanically much more similar than they are different. Suspension is setup different but in those respects they're equally reliable and about the same to work on, more space under the hood though and the hood will open fully vertical, nice feature.

Interior is more complex, has more bells & whistles to break, but the air conditioning works better and the blower motor is MUCH easier to replace. The only thing I can think of to really watch out for is the headliner, if it's starting to sag that can be a big job to re-do, but a wagon is a lot easier than a sedan.

The '90 should be a good car - I'd go for it. The pre-88s (IIRC) had issues, particularly the crumbling wire harnesses. My 765T is an '85 8^(

If the shocks haven't been replaced they are about due, but I expect a mechanic-owner is on top of that.

Mike

I'd like to follow up on two concerns cited by James and Michael. I have an 87 740GL sedan with auto, 159K miles, that I've owned 5+ years. It's running very nicely but it has two problems I'd like to fix. 1) The roof liner is sagging in the rear, and 2) last week I flicked on the high beams and the car immediately downshifted! I flicked them on and off a few times and the car downshifted each time then it stalled while traveling at 40 MPH. BTW, the car had an alternator problem several weeks ago which I fixed by replacing the brush/regulator module and the battery was fully charged when the stall occurred.

You guys said the liner and wiring harness are tough problems. I'm guessing that the high beam issue indicates a short. Do you have recommendations?

Roger

I'd say the cheapest and easiest things to check would be the grounds. All sorts of strange things can happen on a 70 when the grounds start to fail. There are strips near the front of each inner fender where many of the underhood grounds are attached. Clean all the contacts and check the connectors for corrosion.

You say the car downshifts when you flick the headlights...does the tranny actually downshift or is it the overdrive cycling on and off?

Don

First of all, thank goodness you are OK and that your 240 died protecting you.

I have one of each, a 242t and a 744ti, both are great cars and both have their good and bad points as outlined in the above posts. The 740, being the newer car, is more comfortable, and has a smoother ride, it's my freeway cruiser. The 240, after renewing the entire electrical system and wiring harness, is nearly as reliable as the 740, but it is an older car, it's noisier and the ride is more harsh. I love 'em both and would have a tough time deciding if I had to give up one of them, but I would think the 740 would be the better choice over the long haul.

Don

'81 242t, 125000mi '89 744ti, 276000mi

The wiring harness is easy, it can be changed in a couple hours if you take your time, no special tools needed.

The headliner is a several days project, hardest part is getting it in and out without breaking it. When they made the car they put it in before the windshield or back window were in place, it can be done without taking out the glass but it's not easy, you'll have to bend it so far you swear it's gonna snap.

An awful lot of people have used straight pins to fasten the headliner back up. Mine is just sagging for now.

Mike

Not having done this job, I imagine that the headliner fabric has hidden sleeves that slide over stiff suspension "ribs" fastened to car ceiling, and/or the fabric is otherwise pasted up to the ceiling or stiff suspension.

Whatever the skeletal structure, a small needle puncture in the fabric at the lowest sagging point of the drooping headliner will allow one of those small plastic straw barrels to poke through, attached to aim a spray adhesive (several 3M brand products and other brands) to shoot a thin and spotty sheet of glue up between the headliner and its support system. You may even have a few/several very small and unseen puncture points if you have several droops or droop is very large area. When tacky enough to hold, firmly wedge some flexible objects up against the headliner in several spots for the recommended curing period. Pick a glue that does not break down and fail under seasonal changes (record heat or cold temperatures in your area).

Mind you, I've not tried this. Prob'ly very unprofessional, but what do you have to lose?

Don't know if it applies to Volvo, because I haven't tried to tackle ours (it just looks like puffy tan clouds... what's wrong with that?), but I tried spray adhesive on a Dodge we had that had a droopy headliner. The problem was that the headliner separated at some sort of foam layer that broke down. The crumbling foam just kept crumbling, leaving debris glued to the cloth.

Mike

There is a glassfibre shell that the headlining sticks to.

I've tried spray adhesive on mine. Unfortunately it is only a temporary solution - a few days to a few weeks at best. The headlining material is a thin (and very fragile) material bonded to a foam rubber backing. When it starts to sag, it is because the foam has started to collaps, and it seems there is no going back once it has started.

Replacing the headliner is nearly at the top of my 'to do' list over the next few weeks. But I'm sure glad I have an estate.

If you need a guide to the job, there is useful .pdf file here

The 700 series headliner is on a molded fiberglass backing. Adhesive alone won't do the trick, the problem is that the foam itself between the cloth and the backing decomposes, so the only way to fix it is to remove the whole thing, painstakingly scrub off all the old foam, then ideally paint the backing with something to seal it, then apply new foamed fabric.

I drove the car today at slow speed, either first or second gear, flicked on the high beams and it immediately stalled out so the problem seems to have nothing to do with the overdrive relay. The car is perfectly normal with headlights, it's only the high beams.

I looked for ground wires and the only one clearly visible was coming directly off the negative battery post and it was attached to a structural member near the right front wheel well. Things were a bit cluttered on the left side and I didn't see any grounding there or near the firewall which is a typical location on other cars. Do I have to start removing stuff to see other ground wires?

Any wire I could see, ground or otherwise, appeared to have completely intact insulation and no corrosion at contacts. There's not even a trace of corrosion at my battery posts. I know that faulty grounds are widely believed to be the root cause of many Volvo problems but thinking a bit analytically it doesn't seem like a bad ground, which implies an open circuit, could be the cause of this problem, i.e. switch on high beams, open circuit in the headlight electrical path => car stalls makes no sense. I could see some sense to a short being involved but I would expect a fuse to blow in that case.

Any other ideas group?

Roger

d>

That sounds like shorts in the harness, all right. The insulation in areas where it is protected is usually okay, so the problem is probably going to be under the hood. A visual inspection of the small wires where they leave the covering of the bundles may show up something. Try not to disturb them more than necessary - you don't want to lose more insuation than necessary until you reach the point of replacing the harness - but gently separate any wires that seem too chummy with wires beside them.

If still no go, another thought: does the engine still stall if you unplug the high beams? If not, I'm thinking the high beams are loading a voltage down. I've had a lot of trouble with that separate terminal lug on the positive post of the battery - one time it even caused the engine to die when making left turns!

Mike

Thanks for the input....I've had conversation as well regarding a '91

940 wagon with a hair over 200K. this vehicle is, in essesnce, a slight refinement of te 740, is it not???

Yes the differences between a late 740 and a 940 are trivial, many of the body and interior parts are even compatible.