Archived

This topic is now archived and is closed to further replies.

Ethan5150

Broken Timing Belt Help

Recommended Posts

Hi everyone, I'm new to the Volvo community and would love any help you could offer.

I purchased a 1994 850 Turbo last year with about 80K miles on it.  Unbeknownst to me (and certainly my bad for not checking), the timing belt had never been changed.

Last week it snapped.

So I talked to my mechanic who said that despite this car having an interference engine, he's worked on 2 Volvos (similar years) that blew their timing belt and when he replaced the belt, low and behold, they fired right up.  His suggestion was to spend the $23 for a belt and give it a try.

So I went through the entire process of installing the new timing belt.  I made sure the marks lined up on both the intake and exhaust cams as well as the crank.

When I go to start the car though - it doesn't turn over.  In fact, other than all the wheels that the belt runs over spinning, it does nothing.  No firing, no noise - just the whir of the wheels spinning around.

So my question is this:  I noticed that for every turn of the crank, the cams turn twice.  Is it possible that one or the other, or both, of the cam wheels need to be turned exactly 360 degrees to fix the problem?  My mechanic said that it's possible that the valves are open when cylinder 1 is at TDC and that's why it's not firing - because the cams are exactly 1 full turn off.  Is this making sense?  Is there any truth to this?

The walkthroughs I went through to do the belt assumed that I was pulling off an old belt and that those marks wouldn't be moving much during the change (certainly not a full turn) but in my case, who knows how many times each of those wheels spun around when the belt snapped.

Or am I overthinking this and if all 3 marks line up and the car doesn't start it's just plain dead?  I would have thought that if the valves were messed up I'd at least hear something that sounded like the engine trying to do something but no - just those wheels spinning around - no activity at the top of the engine whatsoever.

Someone else suggested that maybe the timing is just off because the old belt had stretched out.  I'm not a mechanic - I don't know how these things work...

The suggestion to figure out if valves may be open was to make sure cylinder 1 is at TDC by putting a screwdriver in socket 1 and spinning the crank until it's at full height - (I'm assuming it should be at TDC if the crank is on the timing mark - is this right?) - and then doing a leakdown test on that cylinder to see if air is blowing out either the intake or exhaust end - and whichever end is leaking, spin that wheel exactly 360 degrees back to the timing mark.  In theory, if the valves aren't toast, then I shouldn't have air leaking through if everything is lined up correctly - yeah?

I'm hoping this car isn't completely toast but you'll know better than me.

Any thoughts?  Suggestions?

I appreciate your consideration!

- Ethan

Share this post


Link to post
Share on other sites

If the belt was installed with both cam marks lined up correctly and the crank mark lined up correctly, then the engine is in time...period. What would change if you turn a camshaft 360 degrees? That's a full circle. Wouldn't the lobes be exactly where they were before you turned it? Also I think you may have written it backwards, but the crank turns 2 revolutions for every 1 revolution of the cam. Not the other way around. If the belt is on correctly, then it sounds like you have bent valves.

Share this post


Link to post
Share on other sites

Get a compression tester, drop a cap full of oil down the spark plug hole to encourage the rings to seal, hook up the compression tester tool and see what you get. If it sounds like it's cranking bizarrely fast, I fear you're gonna see zero across the board.

I would not care which valves are stuck open. If valves are bent, head must come off.

After cranking the engine several times, the marks all still line up? Then I would say you have done the job correctly. You didn't touch the cam gears did you? They are adjustable, so when taking them off you have to make sure you put them back the way they were.

http://volvospeed.com/volvo_repairs_how_tos/engine_repairs/timing_belt_change.html

Did you do basically everything this instruction does?

Share this post


Link to post
Share on other sites

Is it possible that one or the other, or both, of the cam wheels need to be turned exactly 360 degrees to fix the problem

Just by symmetry of a rotating body this can never be the case.

Share this post


Link to post
Share on other sites

If the engine is out of time it will still crank. With the timing belt off, the car will still crank. Not saying it will fire, but it will certinly crank. What else happened when the belt snapped? You have something else going on.

Leakdown test each cylinder. Pull the plug, take it to tdc, and put 90psi in it. Leave it for 5 mins. If it still has 90psi, your good and test the next cylinder. This will tell you how focked your valve train is. I'm guessing its fine as long as it didnt let go at high rpm. Check your starter/starter circut.

edit; Also a compression test is pretty useless at this point, engine wont even crank. And you should never jump right to a wet test, if your compression testing, you might as well have a look at your ring sealing ability while your in there.

Share this post


Link to post
Share on other sites
18 minutes ago, Falcone said:

If the engine is out of time it will still crank. With the timing belt off, the car will still crank. Not saying it will fire, but it will certinly crank. What else happened when the belt snapped? You have something else going on.

 

I'm not sure but maybe he worded it wrong. He said it won't turn over, but then he did say that all of the "wheels" that the belt went over are turning. Sounds like it may be cranking but won't start (turn over?). Probably spinning very freely because it has bent valves, but we'll see what he says.

Share this post


Link to post
Share on other sites

I'm going on the assumption he s turning it by hand to verify his marks. Then he tried to start it and no bueno. That's my translation from his post.

Share this post


Link to post
Share on other sites

Yeah, it's cranking - it's just not firing.  And yeah, it was at high RPM when it broke.  All timing marks are dead on even after trying to start it several times.  Sounds like it's dead, yeah?

Anyone have a ballpark idea of what I'm looking at for repairs? Should I just sell the car as a hunk-o-metal and start looking for a new vehicle? I'm in Hawaii so shipping a new engine here is out of the question. I'm somewhat mechanically inclined and I have a fair bit of tools but I'm also not into taking on a million-hour project or dropping thousands of dollars on this car. Damn shame - it's in great condition... other than the fact that it no longer runs...

:sad:

Share this post


Link to post
Share on other sites

You aren't getting compression, so that's why the engine doesn't sound like anything when it is cranking. If the engine rotated more than 1 full revolution after the timing belt broke then the valves are bent, there is no possible way they wouldn't be.

As long as a valve didn't break you can do a rebuild on the head. Excluding valves the whole job could cost you less than $300, but it will be a considerable amount of work if you haven't ever done a head before. The valves are the big variable though, new you could pay more than $1,000 for OEM valves, and the aftermarket valves aren't worth a shit on a turbo car. You can pull them from a used head for almost free sometimes, but being in HI that might be hard. 

Share this post


Link to post
Share on other sites

Think about it. Interference engine. Belt breaks, bends valves, no more compression, belt replaced, valves still bent so no compression, engine spins freely because....no compression. Do what Fudge suggested...Compression test. I think you will have your answer. 

Share this post


Link to post
Share on other sites

Isn't there a shop a few here have used that sells re-manufactured heads? Otherwise, Hawaii's got junkyards right? I'm pretty sure any engine from 1994-1997 850 Turbo will work, or a 98 S/V/C70 Turbo as a straight swap minus swapping a few electronic sensors off the old one. Figure out whats parts will cost you but selling the busted car is likely to be next to nothing. It may be cost effective to repair if you're willing to do some of the work. If you figured out how to get a timing belt on, you can figure out how to pull the engine with enough patience.

Do the compression test first though. Maybe you're missing something. I say add the oil before testing because you aren't trying to check ring wear, the engine will be cold and oil will have slid off the walls. If you get zero and want to confirm further, remove the intake manifold and you might be able to see the bends.

Real slim odds, but there's a thing called lawn mower syndrome where unburned gasoline washes the oil off the walls making it extremely difficult to start the car. If you crank for like a solid minute or two it'll start to sputter mid-way through, and then maybe require gas pedal modulation to get it to come to life. A dash of oil down the spark plug hole can also help fix this. But don't get your hopes up. Broken timing belt on an interference engine usually has one consequence - bent valves.

Share this post


Link to post
Share on other sites
13 hours ago, Ethan5150 said:

So I talked to my mechanic who said that despite this car having an interference engine, he's worked on 2 Volvos (similar years) that blew their timing belt and when he replaced the belt, low and behold, they fired right up.  His suggestion was to spend the $23 for a belt and give it a try.

Must be a couple of redblock he fixed up.

Share this post


Link to post
Share on other sites

Hi everyone - thanks so much for all your feedback.  I'm not sure what I'll do yet.  I'll plan to do a compression test this week but I think we all know what the verdict is.  I really appreciate everyone's input - you guys rock!  I'll be sure to post what I end up doing with this situation.

Thanks again.

Forum contributors are the unsung heroes of our day!  Cheers to you all!

Share this post


Link to post
Share on other sites

  • Similar Content

    • By V850t5r
      Newly rebuilt engine with new timing belt ofc aaand i'm having issues. The timingbelt moves side to side on the pulleys and cogs, i thought it was the old tensioner so i replaced it. Sounded good at first but after 1 min of running the noise came back. The belt moves about 4-5 millimeters side to side. Any advice? Car runs perfect otherwise so the timing sounds like its correct.
      I kept the tension on the belt while i changed the tensioner, could it be that the belt has settled incorrectly and has to be slacked off and retightened? A video of the noise, will try to get another one w/o cover.
    • By Ronny
      I just replaced the timing belt in my 07' XC70. On a video I watched, the tech removed the crankshaft pulley. I tried this and realized that I didn't have the proper tool. So, I felt around the pulley and found a small cover which I removed. There were 2 bolts holding it on. The timing belt then slipped easily around the crankshaft pulley without removing it. Anyone encounter this? 
    • By st0mpy
         Hello volvo speed!
      I've been banging my head against the wall on this one.
      First of all I'm an aspiring auto tech., I work in a full service shop with a few very knowledgeable master techs who had lent me some advice, but are just as stumped as I am.
      I have been riding a motorcycle every day, rain or shine, for almost three years now. I need  a car.. But I didn't want to just buy a car that ran, I wanted something I really wanted, that needed some work, so from day one, I would have already had my hands all up inside her.. He he
      A good friend of mine, ( who is, or was, a member here.. I remember him talking about it a lot) had a 97 850R, at about 100k miles, he did a lot of top end work, new water pump, timing belt, pulley, tensioner, 5 angle valve job, p&p matching the intake through to the turbo, poly intake spacer, custom intake piping, 20G turbo, 3 inch exhaust straight back to a magnaflow, NA cams, it was a beautiful thing. 
      PO drove the car for about 10k miles after the modifications, purchased a new car, and the Volvo was left to sit for about 4-5 years. 
      PO would drive the car around the block every few months to blow out the cobwebs, but I don't think he even let it fully warm up, he said it had too much power to really put it through its paces, and all he would do is drive it around the block a few times, and park it for a few more months.
      One day PO went to start the 850 for a routine spin around the block, but she just would not start.
      The car sat for another year at least in this condition, with continuous attempts to bring the 850 back to life..
      So here's where I come in, I purchased the car from on him not too long ago, turns out it was out of time, zero compression on 1, 2, 4, & 5.    no. 3 had about 140psi.
      Every intake valve was bent to hell on every cylinder with no compression, and the number two valve head on cylinder one actually broke off.. 
      When PO had his P&Pdone, he also had a head from a t-5 he had gotten from a mutual friend, and had that p&p'd as well.
      So I got a new t belt and tensioner, made a cam locking tool from scrap aluminum, and swapped the fresh head onto the block, with the previous cams and can cover.
      I go to start the 850 for the first time onMonday and she started right up, but sounded a little funny..
      Shut it off,restarted, without a hitch just like before, then died.
      At this point turning the engine over sounded just like I had the plugs out.. No resistance from compression. Compression at this point read 20- 23 psi on all 5.
      I check the timing.. Its out.. WAY out..
      Pull the intake and starter, lock the crank in its safe position, set the time on the cams, put the t belt and tensioner back on, turned the key, and she sounded beautiful!!
      I shut it off, put the serpentine back on, fill it with coolant, started it again, and she sat and purred for a few minutes.
      Now I gave it a few revs, sounded good, gave it a little more..  MAYBE 3krpm..  the engine shuts off..
      Check the timing, crank is set, exhaust cam is set, intake cam is off by 6 TEETH.
      The only things that matter that are unchanged, are the cams, and the can cover.
      I have no idea what would cause this to happen, especially in the first place before I purchased thecar, when PO religiously maintained it and used synthetic amsoil.
      My original question was what the hell is happening.. And what could I do to mend it??
      PO claims that he installed NA cams.. But now he says he can't remember switching them.
      I also read somewhere that the OE cams are all slotted.. But mine are NOT..  What's going on here..
      Now I'm thinking of just going to the junk yard and pulling an entire motor with good compression, and dropping it in with all of the current mods. Will a NA motor work fine with no changes? And what other models of what year use the same motor that could be dropped in and work well with said mods?  Should I just get a NA 850 motor and advance the exhaust and retard the intake just a bit to work well with the turbo and be done with it?  
      I have such a headache with this thing.. I've always loved these cars.. Especially the boss motor thaley come with, and am tired of riding my bike in the rain.. Rainy season just started in Florida, and it takes too long to dry my boots for work the next day.. xD
      Thank you for reading and any advice given.
       


    • By Wesdunns70t5m
      So today at a gas station I notice coolant flowing on the ground from under my car.  Upon a quick inspection I believe it's the water pump (coming from above front passenger cv boot). Luckily I was able to make it home without any problems. 
      I just hit 300k miles so I was planning on doing a complete timing belt job with vivas Kevlar belt kit.
      i was just wondering what's the best guide people have used, and does anyone have any advice or tips before I dive in as this will be my first time tackling this.  Thanks in advance everyone!
    • By Oldariel
      Hello all,

      I am preparing to order all the parts needed for a timing belt change on my 1993 Volvo 850 2,5 glt 20V (NA), however I ran into a slight issue. The engine number sticker on the timing belt cover is gone and I do not have records of the previous timing belt purchases, but i do know that the break in engine numbers betwwen 113154 ond 113155 onwards has to be taken into consideration when ordering parts.

      My question is, can the engine number be found somwhere else? Like stamped into the engine itself somwhere? Or can it be read (guessed) from my VIN? Vida unfortunately does not do that - if I provide a VIN it does not give me the engine number or filter the results for parts accordingly.

      I know I could take off the timing belt cover and try to measure the timing belt width, but I thought getting my engnine number would probbably be more useful in the long run, for future repairs.

      And while I am at it - I should probbably replace the belt, tensioner, idler, damper and water pump. I also plan to replace the cam seals, because the engine is a bit oily under the timing belt cover and a little bit of oil accumulates in the lowest part of the cover. Should I replace anything else?

      Best regards