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Timing belt missing teeth

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Old 08-26-2017, 12:32 PM
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Tampa 928s
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Default Timing belt missing teeth

84 5-speed Euro no sunroof
Owner can't remember when the belt was changed, I bet he will remember from now on!
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Old 08-26-2017, 01:03 PM
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There are conflicting stories on whether the 16V Euro cars are interference, or non-int engine. Also, the heads may have been shaved at one point in its life, thus making a non-interference into an interference engine.

I would remove the battery, and insure the engine is not turned over at all except by hand to set it at TDC for the belt job. If it is interference, he's seconds away from a major repair bill.
Old 08-26-2017, 01:19 PM
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Missing teeth? Must be from the south!
Old 08-26-2017, 02:17 PM
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Since he is all in I plan on stringing an old belt line things up and do a compression check before going any further.
Old 08-26-2017, 02:36 PM
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FredR
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Originally Posted by Tampa 928s
Since he is all in I plan on stringing an old belt line things up and do a compression check before going any further.
Any specific reason[s] to believe the belt might have jumped the crank sprocket? Appreciate the missing teeth are missing for some reason. That 3 teeth are missing and close to each other is suspect. Is it a simple tooth failure thing due to age degradation or was the belt too loose and it jumped causing several teeth to shear in the process?
Old 08-26-2017, 02:43 PM
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James Bailey
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The common t-belt failure is the loss of teeth.....obviously the maximum load is at the crank gear and when enough teeth have left the party it slips.
Old 08-26-2017, 02:52 PM
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He had someone from NY worked on this before he moved to Florida. He said took the car for a drive and wife put up window and car stalled and not even the dash warning lamps came on after that So far there is a burnt wire off of the Ce panel and cut wires on both sides of the doors harness. The battery had a bad cell he replaced it car started but ran really rough, this is what I found. What is concerning me is I had to add a gallon and 1/2 of Coolant and the oil level is over full but seems ok. For now I need to remove everything pressurize the Coolant and look for leaks. Do a compression test drain the oil and look for Coolant. Car has been butchered and owner has to determine how much to put into this. So no not sure what caused the belt to loose the ribs but it's a brand x and sat for years.
Old 08-26-2017, 04:09 PM
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Sounds as though you are going to have a shed load of fun on your hands- should we have a sweep to predict what is going to be the biggest piece of crud in there?
Old 08-26-2017, 05:24 PM
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With the car standing, the oil will "float" on top of the coolant. Grab an oil sample from the bottom of the sump (loosen, drain some, and replace the drain plug). Let the sample stand a bit and you should be able to see if there's coolant or water in the mix.

Pull the plugs now and take a look at them. They need to be out for a compression check, should be out for a belt replace anyway. Coolant leaves splotchy to pure white electrodes.
Old 08-26-2017, 10:08 PM
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If there is lots of coolant in the oil, you will see it as soon as you pull the drain plug. FIrst teh coolant will be coming out and then oil.
Old 08-26-2017, 10:37 PM
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So I guess you guys have my day planned tomorrow!!

From my conversations with the owner overfilled oil and some story about leaking thermostat and 5- different thermostat gaskets it is possible he lost most of the Coolant. I have new oil and filter waiting, going to drain oil first to see what I have before I start tearing into it. The car is about a 7 although original shows 59k 5-speed no sunroof Euro. At what point do you say it's not worth fixing and what would it be worth if repaired. He has 5.5k into it and just basic mechanics of 3k minimum to get it running correctly assuming no blown head gasket, bent valves or bad head.
Old 08-27-2017, 02:40 PM
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Oil looks good no Coolant
The answer the comment about the belt loosing teeth what caused it or was it just an old belt here you go. The oil pump was stuck and took a lot of effort to turn so I am assuming this is what caused the shredded teeth, there are a few more teeth that are 1/2 broken off. Any feedback on these cams and condition not sure if his budget has those in it.
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Old 08-27-2017, 02:47 PM
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Did you get chance to see where the cam index marks were relative to where they should be before you removed the belt? Sounds as though it would not have been possible so the logical conclusion is the belt did jump as the motor conked.

Just a question now of whether the motor was non interference or a bag of bent valves. It will be interesting to learn about why the oil pump is seized or whatever describes its status.

How do these poor cars end up like this given they are more or less bullet proof with a modicum of attention?
Old 08-27-2017, 02:57 PM
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The oil pump was stuck and took a lot of effort to turn so I am assuming this is what caused the shredded teeth

Forget the cam gears, does his budget allow for understanding why the oil pump is 'stuck'?
Old 08-27-2017, 05:13 PM
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The timing did slip but the markings on the balancer do not have a 45degree Mark. Not sure if that indicates that there is no need to set to 45D to install the belt to prevent valve damage like the 32V engines.


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