Grinding noise, coolant leak, sudden death, and now won't start

[850heat]

Hello,

I drive a 94 850.

Yesterday I noticed a slight grinding noise from the right side of the engine. I was slightly concerned, but thought it wasn't bad enough to warrant immediate attention. It looked like there was slight coolant loss.

Fast forward to today. Slight grinding noise was still there. I was driving home, going down a hill, and the engine suddenly died. Didn't notice any particular noise when it happened, no loud smash or grinding. Would not restart, although the engine turns over when trying.

There was considerable coolant loss, and coolant all over the belts on the bottom right side of the engine. I could hear an intermittent regular noise like air getting sucked into the system somewhere.

My initial gut reaction is that this is a water pump/timing belt failure (too bad because both were replaced only 45k miles ago). Since it was almost dark when it happened I haven't tried to crack things open to examine closer.

Should I be worried about broken valves? It seems ominous that it won't start now.

Is there any other issue I should consider?

If it is the timing belt/water pump can I get away with just ordering a new belt and pump, or should I do the whole deal: tensioner, idler, etc?

Thanks for all the help here.

[850heat]

Well, after reading about timing belts for the last hour, it seems like if its that, I'm SOL. Don't think me or my bank account is up to the task of new valves.

Seems like the engine suddenly dying points to the timing belt.

[abscate]

Yeah, that sounds like a water pump seize up. I’m going to guess it was an off brand water pump that failed, not an AISIN or Volvo.

[850heat]

Yeah, that sounds like a water pump seize up. I’m going to guess it was an off brand water pump that failed, not an AISIN or Volvo.

Yep, that was it! Just had a look at it, metal shavings inside the bottom of the of the timing belt case, and unable to turn the water pump by hand. A bit of a bummer.

I was surprised to see that the timing belt was not broken and looks to be in decent shape. Considering this, is there any chance that my valves could be alright?

[erikv11]

Yes there is a chance, though small. The belt may have skipped however, and if it did the question is by how much? A couple teeth won't hurt anything. Several teeth (how many?) and the valves are saying hello to the pistons and RIP head.

You want to figure out if the engine is still in time, that would be informative to know before you take it apart. Since you can crank it over and already have, more cranking is not likely to make things any worse. Walk it over by cranking until the crank is in the mark. At that point, where are the cam gear timing marks?

If that looks hopeful, then I would replace the water pump, time the engine and check for compression. I'd use an old used water pump for that to save on expenses. I think I have a couple around if you need one.

[850heat]

I misspoke about being able to crank it before, I am unable to as the water pump is frozen.

I counted the teeth between the alignment marks on the cam, and the marks on the timing case, and it seems they *might* be off by only one tooth. However I am unsure on the right sprocket, as it looks like there are two marks (I marked 1 and 2)

Here is a picture:

Much thanks for the offer of an old water pump, and if the timing seems alright I would definitely be interested.

[erikv11]

I didn't try to figure out if the cams are in time i.e. nearly one tooth off by counting, trusting you on that. However it does look a little more than one off by another criterion: for a timed engine when the triangle of the cam sprocket bolts on the left (exhaust) cam sprocket sits exactly flat, the triangle on the right sits exactly upside down, like this:

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On that basis I am estimating from the pic that your red mark #2 might be the right one, e.g. if it traveled clockwise to about red mark #1 position then the triangles would be appropriately phased. So that's maybe 4 or 5 teeth skipped, which may be trouble for the valves. Pics sometimes mislead though, maybe you can evaluate for yourself from a straight on view at the fender.

I think you next want to remove the belt and water pump, and get another water pump in there and reinstall the belt, all without letting the cams or crank move. Then with a belt on (just put the old one back on for this) see if you can move it by hand to get the crank on the mark and the cams about there too, and re-evaluate timing and the skip. You won't be able to bend the valves when turning by hand. Once you get it back together with old but working parts, check compression on all five cylinders and that will tell you if there are bent valves.

Otherwise you're going to have to really fiddle with it to get it back in time, for example you could take the belt off and cams out and time it that way, then put it together in time and check compression.

To keep the cams from moving while the belt is off I'd recommend some kind of cam sprocket locking tool (e.g. https://www.fcpeuro.com/products/volvo- ... t-cta-2883?), or people have been creative with zip ties through the sprocket holes to lock them. You can probably google that. If I'm sending you a water pump I can also send a cam lock tool but I'd like it back, or you can buy it from me. I'll go check if I have a water pump now just to clarify that point.

[abscate]

I have an old water pump from my T5 I can send, pm me.

From the position of your Ms I think you are still pretty close to being in time

[850heat]

However it does look a little more than one off by another criterion: for a timed engine when the triangle of the cam sprocket bolts on the left (exhaust) cam sprocket sits exactly flat, the triangle on the right sits exactly upside down

Great, I did not know about the triangle rule for the sprockets.

Otherwise you're going to have to really fiddle with it to get it back in time, for example you could take the belt off and cams out and time it that way, then put it together in time and check compression.

I have read conflicting information about moving anything when the timing belt is off. Obviously ideally you have everything lined up from the old belt and don't touch it, but I've read that as long as the crank is aligned you can move the cam sprockets (clockwise), stated by RobertDyi in this video:

What if I make sure the crank aligned, then I move each cam an equal amount to check the relative alignments?

I have an old water pump from my T5 I can send, pm me.

From the position of your Ms I think you are still pretty close to being in time

Thank you abscate, I am sending you a PM now.

[erikv11]

When the crank is on the mark, you can do whatever you want with the cams, spin them around all day long in any direction.

Unless your car's crank is by chance on the mark already, you are in a catch-22. Need it on the mark to spin the cams, can't spin the cams because it's not on the mark, can't move the crank solo because the valves aren't moving up and down in time with piston movement. At this point it is all about getting the crank to the mark.

One way to get it there without damaging valves is to walk it by hand as described. Alternatively you can remove the belt then move the crank until it causes pistons to jam valves, then fiddle with cams to free them up, then inch the crank some more, etc until you have the crank to the mark. Those are your three options, all have now been described (1) try and keep the timing as is by reinstalling the belt, walk the crank to the mark (2) give up on current timing and try to move crank and cams separately to get crank to the mark (3) remove cam cover, put crank on mark, reassemble.

At this point it is all about getting the crank to the mark.

Then put in time, install belt and an operational water pump, check for bent valves (compression).