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Timing belt question/issue

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Old 12-12-2009 | 02:14 PM
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Default Timing belt question/issue

Parked the car last evening. No problem. This morning turned the key and heard the sound that reminded me of the sound the last time the timing belt broke when I went to start the car. I am assuming this is the case since this is what was found when I had it towed in the last time. As an aside, I think the "mechanic" who fixed the car for me ripped me off but that's another story. I am thinking that the belt may have been close to going and the stress put on in when the engine turned over was its demise. I have two questions. I assume that if you are zipping down the road and the belt goes that is going to result in some major damage. Since I wasn't zipping...

1. IF the belt is broken can anyone advise as to how much damage might have been done by me turning the engine over for 2-5 seconds? If I take it in to the new mechanic I have found, I don't want to get ripped off again.

2. Can anyone direct me as to how I could actually see the belt to see if it is broken? I know that some things obviously have to be removed. Have tools and beer.

Thanks in advance.
Old 12-12-2009 | 02:23 PM
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First what year is your car as this has a lot to do w/how much damage could have been caused.
To see the belt just remove the Air intake Tubes and look into the vent holes on the top of the belt covers.
Old 12-12-2009 | 02:25 PM
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Don't turn over I think is the conventional wisdom and instead take off the 2 or 3 10mm bolts on the PS/DS timing belt covers and have a close look. Track should be 2-3 mm from the front of the cam gear. Post up what you find. You can also peak down the breather holes.
Old 12-12-2009 | 02:39 PM
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Car is an '85 which I understand is the first 32 valve year? How much trouble am I in?

Thanks again.
Old 12-12-2009 | 02:43 PM
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If - and that is a big "if" at this point - the timing belt has broken on any 32-valve engine and some 16-valve engines (Note - it is ALWAYS a very good idea to give complete info in the car when asking questions), then one engine revolution can bend valves.

Whether valves bend depends upon exactly where the camshafts stopped when the belt broke. It can actually be worse if the belt just slips instead of breaking.

Why do you think that the belt broke? If it was properly replaced, it should last a long time - having two belts break in a relatively short time period seems to be pretty unlucky.

If this is a 32-valve engine, pull the intake air tubes off of the engine, get a flashlight and look down into the little vent tubes on top of the belt covers. If the belt looks good, and seems to be tight, turn the engine by hand (clockwise, or tightening direction only) using a socket on the crank pully nut until the "0" mark aligns with the pointer on the cover. Look down the vent tubes, and see if there is a very small notch on the back of the cam sprocket that aligns with the mark on the aluminum backing plate behind the cam sprocket. If there is no notch visible there, turn the engine one full turn back to "0", and look again. If the notches are visible and aligned with the marks, the belt is fine.

Was the belt retensioned a couple of thousand miles after it was installed? It MUST be retensioned.
Old 12-13-2009 | 11:01 PM
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Default Thanks Wally and everyone.

Thank you, everyone.

Wally, the belt was not re tensioned as you mentioned. I had no idea it needed to be and apparently the "mechanic" who fixed the car did not either. In his defense, the work was done some time ago and there were no problems until this incident. New water pump, tensioner, etc.

If the belt did indeed snap, am I safe in my assumption that the only was to see what damage might have been done to the valves, etc will be to tear the engine apart. In a nutshell, I am thinking major labor time resulting in major expense and am considering my options, limited as they may be.

Thanks again in advance.
Old 12-13-2009 | 11:38 PM
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Did you check if it broke yet?

If it broke, yes you more than likely have bent valves.
Old 12-14-2009 | 12:41 AM
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Did it turn over faster than it normally does?
How many miles on the belt?
Where in TN are you located?
Old 12-14-2009 | 01:03 AM
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Can you do your own work? Cheaper, easier and better, if you have the failities and desire.

First, do the checks that have been suggested. Very easy to do, especially if it is a five-speed. If it is a five-speed, you can put the transmission in fifth gear and pull the car forward by tugging on the front of the car to turn the engine to the "0" mark, which is Top Dead Center (TDC).

Look thru the tubes and see if the cam marks are there. If not, pull the car enough to turn the engine exactly one revolution and look again.

There is a small risk involved, but you can look thru the tubes and watch the belt while someone operates the starter. Since the engine has been turned over several times, any damage has probably already been done, if the belt is broken or slipped. The belt should move smoothly in time with the crank pulley.

If the belt has broken or slipped, you can install a new belt just to the point where the belt has been tensioned and checked, but the covers, distributor caps, etc. have not been installed. Pull the fat coil wires from both distributor caps and ground the ends to the chassis, avoiding any wire harnesses.

Pull the plugs and check the compression - you will immediately know if any valves are bent.

If the belt is good, either have a good mechanic retension it, or call Jeannie and get the $60 tool so you can tension it yourself. Two hours of easy work the first time, thirty minutes the third or fourth time.
Old 12-26-2009 | 03:46 PM
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Wally and "Blown '87"

I am in the Nashville, TN area. I certainly do have the desire to do the work, Wally and might be able to find a place to do it, but am probably lacking in the area of expertise. In answer to the other questions Car did not turn over faster but slower when tried to start it. I am trying today to see if I can see the belt since it is finally a little warmer outside. Speaking of "expertise" or lack thereof, my problem is that when you guys mention pulling the "air intake tubes" off of the engine, I'm not sure what you refer to. Are they the tubes that run on each side of the engine back to the air filter??? Somehow I don't think so. I know there was a site at one time that showed the engine and had a "what is it" section but will have to google to find it again. Thanks again for everything. I am vacillating between getting it fixed, selling it to Pull a Part or sticking it in storage until I can do what needs to be done and getting some basix transportaion in the meantime.
Old 12-26-2009 | 03:53 PM
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Originally Posted by PatrickP
Are they the tubes that run on each side of the engine back to the air filter???
Yes they are. Go pull them right now and then follow Wally's directions. It'll take you 5 minutes and save you hours of stressing about a broken belt.

Go...
Old 12-26-2009 | 04:10 PM
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Duh!

NOW I know what you guys are talking about! The little tubes that used to give me such a hard time when I was putting the air intake tubes back on when changing the filter, etc. Going to look now to see if I can see anything. Thanks! I'll let you know.
Old 12-26-2009 | 04:38 PM
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Update:

Looking down the breather holes the belt does appear to be intact. Now, assuming I have a socket for the cam, I will crawl underneath and see if I can see anything that makes "until the "0" mark aligns with the pointer on the cover" make sense to me!
Old 12-26-2009 | 05:07 PM
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Final update for the day:

Well, it looks as if "until the "0" mark aligns with the pointer on the cover" is moot for me at the moment as I do not have a socket large enough to fit on the pulley bolt. Anyone know the size for future reference? I also made a mark on the belt through the breatther hole and followed Wally's suggestion (you can look thru the tubes and watch the belt while someone operates the starter) and the belt did seem to move just fine. Starting to think I may be looking at the wrong problem. My wife mentioned that she remembers when I was initially parking the car that there was a noise "when you turned" and I am now wondering if there might be a problem with the power steering pump. My thought process is that if it maybe froze that this might explain the "strained" cranking. Guess I could take the belt off, or just cut it, to see it it is turning smoothly. Then again, I feel as if I am giving a whole new meaning to the phrase "grasping at straws" and it may be time to have the darn thing hauled into someone who knows what he''s doing.

Thanks again to everyone for all of your help. Any more suggestions are welcome!
Old 12-26-2009 | 05:52 PM
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27mm and you will need a short extension too. You could, carefully bump the engine over with the starter too. It takes a long time to get it to line up with O/T, but it's duable. At the same time you can ask you wife to see if the PS pulley is turning. If the PS pump is siezed, and you don't mind cutting the belt, go for it.



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