Buying (bought) a Volvo 850 1996

[DennisCA]

Most of these hoses are still flexible and I haven't been able to break them, given their good condition I think they're Volvo OEM parts and worth reinstalling. I am pretty sure this PCV system has been replaced earlier and it's not the original one though given how good in shape it is. I've been banging the oil trap on the work bench to get bits loose and based on what I've read for other people their oil traps just disintegrate.

The reason I am doing all this is the car was a bit of a gamble, the service book is gone and there are no stickers showing when the last belt change was made except one from 2002 at 75,000km. I was also a bit paranoid about the engine being out of time, but as I've been able to verify now it's actually pretty well timed. I found some red paint marks when I removed the timing belt cover too and they lined up.

The serpentine belt looked fresh too and from what I can see of the timing belt it also looks pretty good. But I have absolutely no idea how long it has been since last time. Hence I am doing all this before starting to use the car properly.

I've been at this project on and off for a week now by the way. I work slow... Reason being volvo engines are new to me, everything here is unfamiliar and I keep stopping and looking on the net for every little thing I am unsure about.

[DennisCA]

New vacuum lines, these are actually fuel hoses.


The flap on the bottom of the air intake box was kaput so I disabled it permanently


The new belt is on




Used a 16mm fuel hose as suggested for the new PCV line


And I've started the engine tonight and it works, except one odd thing, It idles well and fine, but when I hit the pedal (car is in neutral) it starts hickuping and almost stops, the dash lights dim before it catches up. If I press the pedal more slowly then it smoothly revs up but not if I depress the pedal too fast.

[DennisCA]

I've now flushed the coolant and replaced it with G48 (blue-green, HOAT coolant) and also replaced the engine oil (5W40 synth) and filter.

Last night I drove the car 80km and the earliest hickuping issues are gone, though I think plugs, a new rotor and distributor cap could be good. I almost didn't get it working though, as I was replacing the thermostat (I modified the old one to always be open) I dropped one of the torx screws down the between the block and intake, it fell all the way down and I wasn't able to locate it.

In the end I found that one of the old water pump screws was the right thread and would do the job, at least temporarily.

[DennisCA]

My weekend project for the Volvo is the rear bumper, the rear brackets are rusted through and it was only hanging on by the top part on the drivers side.



This here is the worst part on the car itself, nothing here looks structural. I'll just cut away the worst and primer it with this red rust primer that I think works well (tested on a piece that's been outside a year, even underwater from time to time).

After the primer dries everything gets brushed with linseed oil. Very few things can penetrate like raw linseed oil can. It's one of my go to oils for rust treatment. It's one of the few things that can soak into even heavy rust and get down to bare metal and stop the corrosion attack.

Dinitrol ML is a commercial product almost as good at penetration. But it does not oxidize and create a tough layer, that layer also swells as it oxidizes so I brush it on seams on cars so it'll penetrate in between the seams and stop potential hidden rust. Then it expands and seals the joint so no water will get in there. However this is the big downside, it takes so long for it to oxidize. That's why if I've had some Dinitrol at hand, I would have used it instead. Linseed is best to use in summer and spring. But I make do with what I got.

Tomorrow I will apply thicker rust protection that'll be more like a barrier and cover and protect . If I went straight t that without using something thin and penetrating first I'd just make the problem worse and seal in the rust. Anyway this is how I approach rusted vehicles.







This side has little rust but some, I have removed it, primed and oiled. Everywhere will get coated tomorrow.





I'm working on these bolts that the bumper brackets will attach via once I am ready for that. I thought the back bolts were loose so I just lobbed them off with a zip blade, turns out that was a mistake. Gonna have to drill these out. On the drivers side I remembered that I have these extractor bolt for rounded bolt heads, they worked great and I got the bolts out just fine on that side. Now I just got the passenger side left.

[DennisCA]

Fabricated new brackets today.





Fits on the bumper too, note threaded rod.


Primer


Then another paint after primer


First bracket attached. I've also brushed down the areas I soaked in oil with bitumen based rust proofing.



The paint on the 2nd needs to cure a bit yet.

[Vapari5]

Great progress! I have been restoring my 96 850 for the past 2 years, mine is the same color (422-21). There is actually a Turquoise 850 for sale in Salo with VGS-610 Numberplate, You are doing a good thing by keeping another Turquoise P80 on the road, they are quite rare.

[DennisCA]

Thanks! It's been getting more work done to it, and had new issues pop up too. Most irritating is the SAS pump, I've used the diode trick to disable it creating an error code but I can hear it starting now and then. Looks like some rubber parts on it has broken and it's going making a repeating annoying thunk thunk sound sometimes. I should cut the power cable or something.

And then I got no engine heater anymore because the breaker now pops every time I use it. Didn't help to clean out the plug, all the wiring looks OK as well.

[scot850]

Does the fan motor run at all? Sometimes you can remove it and add a little oil to the bearings to get it running again. If it is not running at all it could be the bearings are really worn. What then happens is the fan cage moves forward and backward on the loose bearing when you accelerate and decelerate. This will often make the cage stick, especially when accelerating. If it is that worn, then the only solution is a replacement fan.

The other main issues are the resistor controller. There are 2 different ones depending if you have the MCC or ECC units.

Finally there are the ECC/MCC units themselves failing.

You should also consider cleaning the 2 air temp sensors hidden behind the handles above the door. They won't likely be causing the issue you are having but worth doing to control the cabin temp. Generally they never get cleaned and will jam the little sensor fans in them.

There can be other issues but those are the more common ones.

Neil.

[DennisCA]

I think you misunderstand, I am referring to the SAS airpump, the one which sits under the battery and injects air into the exhaust manifold when the engine is cold.

[scot850]

Ok. When you talked about engine heater, I thought it was a separate issue! So I thought you said you had done the 'diode' trick which should mean it is disconnected and not working at all? The SAS pumps fail from the valve at the exhaust manifold failing and allowing the condensation when the engine cools ad warm up in the exhaust system to drain directly into the SAS motor. This eventually rusts the SAS pump and it stops working. If it has only recently stopped working, remove it and drill a small hole (about 4mm) in the bottom of the case and allow the water to drain out and let the pump dry out. You could then try to shock it back into working with 12V directly to the pump. Spraying some WD-40/penetrating oil in may also help. Even if you get it going, you should replace the valve to try to prevent it happening again, but the pump should hopefully now drain with the hole in it.

You probably know the pump only works at start up to increase air into the exhaust gases to reduce the emissions from the tailpipe. Once the engine is up to temperature, it stops running. If your car has emissions test requirements, you will need the system working or take the car in hot!

Neil.