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Timing Belt Snapped, are the valves hosed?

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  #1  
Old 10-29-2008, 03:40 AM
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Default Timing Belt Snapped, are the valves hosed?

So i changed my timing belt like 3 months ago and the other day I started the car warm it up and it just died.
Instinctively I tried to start it and it whirled over really fast like when you take all the plugs out. So I pulled the distro cap and confirmed the rotor does not move when you crank.

Broken belt!

So I didnt hear any clanging or anything when it went or when I turned it over afterwards. The question is- are there bent valves?

(00 EX D16y8)

Thanks

-Scott
 
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Old 10-29-2008, 05:04 AM
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You always run a risk of engine damage when the timing belt snaps. You'll need to reinstall a new belt to test for damage by compression testing the cylinders:

https://www.hondacivicforum.com/foru...ad.php?t=40559

By the way, the belt snapped probably because it was not installed correctly. Did you replace the belt tensioner and then properly tension the belt during installation?
 
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Old 10-29-2008, 05:27 AM
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We did replace the tensioner- it was a timing belt kit we got off ebay. (so it was probably just a cheap belt)

We have the manual and we went step by step, though the tensioning section didnt make very much sense. We researched and found some magazine articles online with a walkthrough but they also were very vague about the tensioning bit.
So it is very possible I had it too tight.

Whats the best way to know if it is tight but not too tight?
 
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Old 10-29-2008, 05:49 AM
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Originally Posted by wookieneck
We did replace the tensioner- it was a timing belt kit we got off ebay. (so it was probably just a cheap belt)

We have the manual and we went step by step, though the tensioning section didnt make very much sense. We researched and found some magazine articles online with a walkthrough but they also were very vague about the tensioning bit.
So it is very possible I had it too tight.

Whats the best way to know if it is tight but not too tight?
Here's a good place to purchase the timing belt:

http://www.hondaautomotiveparts.com/

What specific part of the belt tensioning procedure (see below) did you find ambiguous?

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Old 10-29-2008, 07:08 AM
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can almost guarantee you have more than a couple bent valves.
 
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Old 10-29-2008, 07:14 AM
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Originally Posted by riceburner700
can almost guarantee you have more than a couple bent valves.
What course of action would you recommend to the OP at this point?
 
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Old 10-29-2008, 08:32 AM
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If you want to check without going thru the whole installation of a new belt...

Turn the crankshaft so the timing mark is 90 degrees out. Now all 4 pistons are at mid-stroke. Then you can turn the camshaft any which way you want.

Now go thru the motions of checking the valve clearance. Any valve that has large excessive clearance is bent. At this point you can decide whether to ditch the engine or fix it.

Theres a chance that a valve or 3 is very slightly bent so it looks OK with the above check. If you securely lock the crankshaft in place, you can try a leakdown test.
 
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Old 10-30-2008, 03:22 AM
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Nice, well maybe I can get something out of it for salvage then.

The whole "turn it 3 teeth" and it will be tensioned thing sounds super simple but when you actually do it- nothing really happens and the belt seems all kinds of loose. So I just tighted it until it felt like an average accessory belt and walked away. Worked fine for 8 months (did the math and figured out exactly when we changed it)

The car has a salvage title so I dont really see any point in dumping any money into it if there are bent valves. Which is a shame since the motor has 101k on it..
 
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Old 10-30-2008, 12:12 PM
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well I sent it off to a mechanic who is going to throw a belt on and then we can do a compression check and stuff. Hopefully it isnt all that bad and its driveable still.

I cant afford to keep driving my cummins back and forth to work.
 
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Old 10-30-2008, 01:33 PM
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Originally Posted by JimBlake
Now go thru the motions of checking the valve clearance. Any valve that has large excessive clearance is bent. At this point you can decide whether to ditch the engine or fix it.
Unless the valve clearance was maladjusted to begin with

it's 8 years old and i doubt the valves have been adjusted, so i bet they're out of whack
my car is a 93 with 162k and had never had the valves adjusted until I did it a month ago. They had WAY too much valve clearance.
 

Last edited by trustdestruction; 10-30-2008 at 01:57 PM.


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