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940 - Chasing Coolant Leaks

How much of a pain is it to get in there? If it's easy, I'd do the freeze plug (cleaning up the area as much as possible to help it seal)... worst case you're out $5 plus the cost of a coolant drain and refill.

I'm presuming you don't need the block heater despite being in Canada, since you have been without it for a while. It might be a future selling point for the car if you can get a modern one.
 
How much of a pain is it to get in there? If it's easy, I'd do the freeze plug (cleaning up the area as much as possible to help it seal)... worst case you're out $5 plus the cost of a coolant drain and refill.

I'm presuming you don't need the block heater despite being in Canada, since you have been without it for a while. It might be a future selling point for the car if you can get a modern one.

For someone like me who works slow and methodical, its a several day job. I am pretty sure ill have to pull the exhaust manifold and turbo, downpipe, the coolant hard line, the oil filter.

I might be able to get away with leaving the manifold in and only removing the coolant hard line and oil filter.

My engine has the cup style freeze plugs (which I found a new one among my parts stash) which seem to be held in with either loctite #1, or a gasket material, (I read grey so I would use Hondabond), Permatex Aviation, or even JB weld.

https://www.fcpeuro.com/products/volvo-freeze-plug-cupped-genuine-volvo-3531239

I don't really need a block heater as it's a summer car. Even still, the winters around here are pretty mild for cars and most people don't use a block heater (although I do have and use one on my winter Subaru on the coldest days only).
 
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So I got up in there today and pulled the oil filter off, the oil cooler hoses, and the hard coolant line.

The screw was loose on the block heater but I am doubting that it is the block heater anymore. It looks like it is coming from higher up, and the only thing higher up is the headgasket... I still want to pull that block heater out if I can, I already spent $30 on dry ice for the expansion plug (and thus have also give myself a time limit to work against)

Is it likely on a B230 that the HG is dripping so much coolant? It empties the overflow bottle after a short drive or overnight. I am in the middle of removing the exhaust manifold (and turbo and downpipe) to check it out closer. I can't get the hard coolant line out to inspect it yet but it is the original from 1992, it seemed fine when I had it out 2 months ago. I can't figure out where the heck else it would be leaking from.
 
Yes, the head gasket can leak that much through a crack in the gasket. A customer of mine just left in his 940 that has this problem. On his car you can clearly see the trail of coolant coming down the side of the block right next to the oil separator box. His car has 350,000 miles on it and has bad blow by on the rings. It isn't worth doing a head gasket on it. I sent him to the auto parts store with a picture of a bottle of Bars Leak sent to his phone. The Bars Leak might buy him some more time with the car. Another customer of mine drove his 940 for over a year with a minor head gasket leak out the passenger side below exhaust port # 4. He finally brought it to me and had the gasket replaced. The gasket out of that 940 had a crack in it that looked like the gasket had been cut with a razor blade. The Bars Leak would plug it fine for 2-3 weeks, then, it would leak a small amount of coolant and seal itself back up.
 
Well, I guess I will either have to use a bottle of this stuff, or just try to replace the HG myself.

I'll probably attempt the HG as I already have an Elring HG and Mahle Head Bolts on hand, and am halfway to having the exhaust manifold removed.

Thank you!
 
If I was that far into, I would just keep on going. A 940 Turbo head gasket job is 6-7 hours total if you know what you are doing. Honestly, even if that doesn't turn out to be the problem it will be the best preventative maintenance you can do for peace of mind. The turbo cars are just waiting for the most inconvenient time to blow their head gasket at this point. Too many years, miles, heat cycles by now. Even a 1995 940 is 25 years old.
 
Mine lost coolant in a similar way when I had an exhaust to coolant leak.

I agree with 2manyturbos, though. Replace the head gasket. It's a good experience. The sealer in a bottle is for cars that you plan to push off a cliff after a few weeks.
 
Well, I certainly can't admit to knowing what I am doing, but I want to get it done, and most people seem to say it's pretty simple!

Thanks guys!

Edit: Well it turns out that the HG I had on the shelf is a Victor Reinz. Hopefully that's good enough to last me!
 
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I'm going on 80,000 with my Reinz head gasket. Just make sure you clean the mating surfaces as good as you can. Keep going until there's no rust or dirt left, then keep going further until you stop seeing new rust on your rags entirely.

And if you have any doubts about anything you're doing, I'll try to answer any questions you have. Don't consider any question too stupid to ask, because this is one of those things where how close you get it to perfect will have a big impact on how long it lasts. And not all the data you need is immediately available.
 
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A Victor Reinz head gasket is fine. I've used them several times. Not on the same engine. :) They hold up fine. I think that is what is in my 940 Turbo, IIRC.
 
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A blurry photo I took at the last minute, but I got the head ready for removal tomorrow. I will bring a straight edge to check the head, as one of the heater core hoses and one of the oil cooler hoses were aftermarket when I bought it, so potentially it has dumped its coolant at some point and overheated.

I will be replacing the cam, intermediate and crank seals, as well as the water pump, while the head is off.

I opted to swivel the exhaust manifold and turbo and downpipe, and just pull back the intake manifold. That should give me enough room to remove and replace the head.
 
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Replace the timing belt and its tensioner while you are at it and be sure to adjust the valves.

Also the hoses and belts if at all dicey.

On the subject of head gaskets, is there any consensus about spraying on a product such as Copper Coat gasket compound on the bottom of the HG to help it to seal?

I've done the last two HG jobs using that and have had no issues.
 
Replace the timing belt and its tensioner while you are at it and be sure to adjust the valves.

I'll have to look into adjusting the valves, I do have a bunch of shims on hand. Never done it before. This Headgasket job came about 3 months before I was mentally prepared to do it lol.

Some other parts I am replacing:

Cam gear for an STS adjustable
Cam Gear Pin for a solid stainless pin
Tensioner spring (OE) and roller (INA) although the INA roller on there was pretty good shape.
Timing Belt
Alternator Belt
P/S/Water Pump belt
AC belt is being left off for now.
 
I'll have to look into adjusting the valves, I do have a bunch of shims on hand. Never done it before. This Headgasket job came about 3 months before I was mentally prepared to do it lol.
I wasn't prepared to replace my head gasket at all when my car started throwing the white smoke. I didn't think I could do the work myself, at all.
Think about replacing the nuts for the exhaust and intake manifold too. It will look really good when you put it all back together. You'll want to use locknuts for the exhaust.

On the subject of head gaskets, is there any consensus about spraying on a product such as Copper Coat gasket compound on the bottom of the HG to help it to seal?
I was told to install my head gasket dry and not use sealant. I have seen it recommended before, but only for all aluminum engines.
 
I wasn't prepared to replace my head gasket at all when my car started throwing the white smoke. I didn't think I could do the work myself, at all.
Think about replacing the nuts for the exhaust and intake manifold too. It will look really good when you put it all back together. You'll want to use locknuts for the exhaust.

Thanks! I am kinda just trying to keep moving forward with the steps until it's done!

I recently replaced all of the studs and nuts all the way around, intake and exhaust, they looked great! I used copper nuts on the exhaust manifold, and Volvo nuts everywhere else. After a few dozen heat cycles they don't look quite as nice, but they came off really easily (although a few backed the studs out, which I'm more than okay with compared with stubborn, broken studs! I use copper anti-seize and it seems to be working well.
 
Put some of that anti-seize on the spark plug threads to make them easier to remove as well as some dielectric grease on their tip and adjoining white ceramic area also.
 
Head is off, and I scraped and scraped all of the gasket material off using a razorblade.

It feels smooth to the touch but doesn't look very clean, I went at it with some degreaser but it looks like there is oil baked into the surface or something. How clean is clean enough?

I also couldn't find any obvious sign of split HG....although there was definitely some bubbling/rust on parts of the gasket. Nothing was split that led to the outside of the head. I checked the head and block with a straight edge and it seems pretty bang on.

I installed the front cam seal, but poked it in a little past the chamfered edge. Will this be a problem? I had asked on the Turbobricks Discord and was told that it should be fine, and that some people even push it in a bit further if they have a worn camshaft.

I went to install the intermediate shaft seal, and tore it, even though I was using the Volvo special tool. I had to go back to Volvo to pick up a new seal. If I rip another I will be using the Reinz seal I have on hand. I was using Moly (LM 48) to lube it, the parts manager at Volvo suggested vaseline instead as it's less slippy.

Any tips on replacing the crank seal while the engine is in the car? I'm thinking it will be better approached from below.
 
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After finding that you have already taken the head off did you check the heater hoses and pipes including the heater control valve for leaks?
 
After finding that you have already taken the head off did you check the heater hoses and pipes including the heater control valve for leaks?

I did check and they were dry, but old, so I replaced the heater hoses as well as the heater valve. It was still dry before I started down this HG road.

The leak is coming from the exhaust side, I thought it might have been the coolant hard line or its heater hose connection above the bellhousing, but every time I felt it, it was always dry. The only place with a leak potential that is above the block heater is the HG as far as I can tell.

I can access the block heater a lot better now but still can't budge it from the hole. It's getting close to the point where I'm going to be forced to figure it out, because I'm on the verge of damaging it in the attempt to extract it. The tightening screw is loose and spinning, but the plug isn't budging from the hole yet.
 
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