Hi, I've been lurking here awhile and have learned lots of stuff from you guys.
So I have a Volvo 850 GLT 1995. which has been beat on pretty constantly by my wife and daughter. I came back after over a year working out of State and did the following:
2 New front axles
2 lower control arms
2 new struts
New front brakes
new PVC oil separator
clean up of egr valve
new fuel filter
new fuel pump
new fuel pump relay
new crank position sensor
new timing belt and water pump.
Anyways, the car ran fine for over a thousand miles and then all of a sudden it would not fire up. It cranked but did not fire up.
After checking everything that the forums suggested I found out that the timing belt had slipped. So the marks at the top aligned up but the bottom [crank?] sprocket mark was 4 teeth off. So I redid the timing belt to the correct marks and presto! she fired right up. I did a compression test and 2 of the cylinders were quite a bit lower but she ran pretty good. But ONLY for 4 miles. Then she " clicked " and would not fire up as before.
The car has 190,000 miles. the previous timing belt had 70,000 miles.
Could it be the the timing belt is slipping because of a bad tensioner pully .
Should I put more time and money into this or is my engine no good ?
Also are my valves damaged because the timing belt slipped a few cogs ??

Thanks for all replies.

 

If the crank was more than 2 or 3 teeth off you could have damages a few valves. What were your compression numbers?

When you did the tb job, did you compress the tensioner? If so, did it leak? Did you spin the rollers? If so, did they spin freely?

Check the timing again, if it's off AGAIN it's always best to figure out WHY.

If you can afford to replace the car with a new one that will be fine with me. If you bent a few valves you can replace the head or have that one rebuilt. Not sure what condition the rest of the car is in but I have over 220,000 on mine and plan to put another 280,000 on it.

 

Could it be the the timing belt is slipping because of a bad tensioner pully .
Should I put more time and money into this or is my engine no good ?
Also are my valves damaged because the timing belt slipped a few cogs ??

Since you found the belt off by four teeth it's almost a certanity that it's the likely cause of the no start. Pull the cover again and confirm.
My guess is one of two things happened. Either the tensioner is failing and allowed the belt to slip or something is causing the cams or crank to bind.

More time and money ? More time yes. First find out what and then you can decide if you have the money and or want to do what the repair will be. Find out if the belt did slip again and can you post the compression results? It's likely the valves were bent and if so you'd need to pull the head to have it repaired. There's always a chance it's something else that failed that caused the current problem. Not likely, but possible.

First things first, check it over to see where your problem is.
You might want to go to your control panel and add your location. Once done it pops up on your posts.

 

Hi, someone else did the compression test.
I believe the high number was 140 to 150. The 2 lower cylinders were 110 to 120.
When I did the TB, I did compress the tensioner and it did not leak and as far as I can remember it did not bind up.
Later on this week I will pull of the timing cover and see if the belt has slipped again.
I see FCP Groton has a a kit for $214.00. that has all the pulleys, tensioner and another belt. Maybe I will order one and see if that will do the trick.
As for the valves I guess if she don't start up with the redone TB, then it's a new head job. Ouch !!

 

When I did mine I used their kit. I sourced the water pump from Oreilly.

You have a lot of new stuff in here and if the head job doesn't scare you off I'd suggest doing the water pump at the same time. It just cuts down on having paid all that $$$ and having a pump fail before you do another belt. There will definitely be suggestions you get the Volvo pump from FCP too. For me I had a discount at Oreilly and I trusted the rebuilder.

 

Thanks for all the replies. The car is in pretty good shape and i do want to keep it. However i'm afraid that the problem might be internal . Has anybody ever had this happen to them ? And yes i did install a new water pump when i replaced the timing belt. This old volvo is so well built it would be a shame to junk it.

 

What shape were the rollers in?

Also, did you install the white plastic clip on the tensioner tip?

Those compression numbers are very low. You need to have that checked again. Make sure they do it with the motor warm or hot, and do it right. Maybe it's a bad gauge but if those numbers are correct that motor is in bad shape.

 

Like this- - - >

 

Thanks Kiss, sometimes I respond on my phone and it's hard to link pics, etc.

That plastic piece is designed to prevent the tensioner roller from giving enough slack to cause the belt to jump any cog teeth.

My take on timing belt parts:

My take on compression:

 

You know me, one picture is worth a thousand "that thingy on the left under that hose with the electrical connector"

Like I always say, "follow the arrow".

 

Uh, like rspi said, those compression numbers are very low; min spec on that engine is over 180 psi; you'll start seeing misfires below 150 or so. Throwing a TB on there may be a waste of time unless you plan on doing at least a valve job too.

 

Thanks for the info. You guys are very helpful. I ordered the timing belt kit. The white plastic thingamajig was there. I feel like I should pull off the head while I'm waiting for the parts. Any helpful hints. I have never done a volvo head before, but think I should do it. I can take the head to a machine shop and have it rebuilt. What do you think ?

 

Or should I get a new motor? Well I can't afford new so it would have to be used.

 

If you can get the car started and warmed up, double check the compression numbers to make sure you didn't have a bad test. If they are really that low, get another motor, unless you can do a leak down test and verify that you have some bent or burnt valves.

I've never done a motor swap but here is a link to my head swap:
Head Removal and Installation, Volvo 850 / S70 Turbo B5234T, B5254T, Head gasket replacement, valve replacement.

I hear a motor swap may be a little easier, just have to cross your fingers that you get a good used motor.

 

Well I did it. The head's off. Thank you for the link to your head swap. That was amazingly concise. The head looked ok . Didn't notice anything bent or broken that I can see. A lot of carbon and gunk. Anyway the cylinder head is off to the shop tomorrow for a shave and a thorough cleaning and restore. The guy at the shop said that he will only change any springs or valves if they are broken. A lot of antifreeze spilled onto the top of the pistons. Should I order new bolts with the gasket kit. I am quite worried about putting it all back together. Oh Well in for a penny in for a pound ! I'll take any special tips or advice from all you guys .

 

Man, I tried to put all the tips in those instructions. Clean it up as best you can.

Yes do get new bolts. And the Valve Stem seals come in the kit. You should send those with the head. If they are leaking they will replace them. If they don't use them, I might purchase them from you.

 

Yep, new bolts for sure, and don't even think about doing a valve job (even just an R+R valves and clean-up) w/o new valve guide seals!!

BTW: PG: it would have been nice to do leak down test (like rspi suggested) before you did a tear-down. I.e. think you're assuming most/all of your compression loss was due to the valves, but that's only an assumption...

 

So I did give the shop new valve seals. He is doing a valve job.
I think the low compression was cos he did the test when the vehicle was out of time. The cylinder walls looked pretty smooth and the car ran really good before the no start. Studs from fcp groton too ??

 

Studs from FCP are fine. I am glad you are getting the stem seals replaced. I was a bit worried as I read through this thread. Every head I have replaced has needed new stem seals. They were all hard, I am glad you are getting this done. Makes no sense to go through all this work and not replace them.

As for the cylinder walls, you can hone them in the car. You will not be able to get down to the bottom of the cylinder but you will be able to get rid of the glazing. I would recommend a bead honer, not a bar honer. You will need compressed air to blow anything that makes its way down to the rings. One of the cars compression I bead honed went from 145 to 176.

Here is a glazed cylinder after a bead hone

 

What are studs?

And that block looks like it's out of the car.