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Broken timing belt

Old 10-24-2001, 09:46 PM
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Join Date: May 2001
Location: Paramus, NJ
Posts: 54
Post Broken timing belt

I just broke the timing belt on my '86 951. I have three questions please: 1) how much will this repair cost at the dealer assuming no other repairs or damage; 2) is the stock '86 951 a non-contact engine (what are the chances of bent valves); 3) how difficult is it to replace the belt myself assuming above average mechanical skill (did this once before on a Toyota Corona).
Thanks for all the help Listers.

Steve '86 951
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Old 10-24-2001, 11:10 PM
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Location: Santa Barbara, CA
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Oh, first time out, count on 5-8 hours to do your timing belts. You'll need the following tools:

    Nothing terribly difficult, just follow the instructions in the manual.
    Danno is offline  
    Old 10-25-2001, 12:23 PM
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    Location: A suburb of Silicon Valley, CA
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    I pushed the envelope and at 45,000 BELT MILES our 85NA gave up the cam belt. I must admit I could hear the belt slaping around at idle. I knew the 2/30 rule, but then we dont always make the right decisions. Teeth were everywhere in the front cover. Bent all four exhaust valves (looked kinda cool actually). No piston damage. A local machine shop replaced the 4 exhausts, reworked the guides, did a complete valve job and resurfaced the head (I believe that due to the high compresion ratio of the NA, a head can only be surfaced once)all for $700US. I removed and replaced the head.

    I feel for you man. My biggest hurdle was talking the wife into spending the $ on the repair. While she loves to drive the car, she does not understand routine maintenance costs "Just go get a cheap new honda that wont break". Sends chills up my spine!
    Bill is offline  
    Old 10-29-2001, 04:35 AM
    Join Date: Jun 2001
    Location: Tustin CA
    Posts: 102

    ok just did this one

    1. yes it's a contact head and you did bend a valve ( at least assume you did 95% do )
    2. you will have to remove
    a. intake manifold
    b. more plumbing than the sears tower
    c. cam tower & lifters
    d. Exhaust manifold.
    remove the intake and stuff is about an hour or so job.. just make shure you remove all the hoses from it before you take it off there is nothing to hold if on if everything is off. You will need a set of Metric allen heads ( I reccomend Craftsman I know they fit ) to remove the cam tower and other stuff. Cam tower is straight forward remove the bolts from each end first and work towards the middle as the springs will lift it up on each end.. mark which lifter goes which hole ( ziplock bags are the best )
    remove the six bolts holding the exhaust mainifold to the headers remove the head bolts and slide the whole assembly up.

    get the widefire head set from paragon $120 I think.
    send the head out you'll need new guides ( they all do ) and the seals are with the head kit. figure $100 a valve other than that i got mine done for $300 at a local shop.
    assembly is the reverse the belts really arn't any harder to do than your average Toyota or BMW.. get someone who knows to check the tension after your done an off the cuff way is to tension it till it wines then back it off. mark hoses and lines as they are a nightmare . took me about two weeks weekends and nights but I did alot of other stuff. it's not an impossible job at all just take it slow things seemed screwed up they are ( I almost had to replace my cam tower becuse I didn't understand how to remove the cam gear.)

    Good Luck

    lordgrommit is offline  
    Old 10-29-2001, 04:28 PM
    Join Date: Jul 2001
    Location: New Hampshire
    Posts: 170

    Take some pictures as you take things apart. Especially pics that show the vacuum lines/plumbing ... it will be good reference when you go to put it all back together.

    -Bob P.
    rplencne is offline  

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