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Old 10-27-2004, 01:48 AM   #1
dreaminsubys
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Question Timing Belt Woes 98 2.5 DOHC

So I finally found the time to put the engine (98 2.5 DOHC)back in my outback after replacing the head gaskets. When I started the car there was a fairly loud "bap bap bap" at cold engine idle speed. When I gave it some gas it went away. The car seemed to running all right. Long story short, it turns out that there was enough slack in the timing belt that it was hitting the plastic cover. You could see it flapping around with the cover off. I am almost positve I put the belt on right. There was one mark on one the top of the left side intake that did not quite line up with the one on the belt so I counted the teeth, 51 teeth to left intake, 54.5 to top of right intake. I was thinking that it might be the tensioner. The weird thing is that after running the engine a couple more times. The slack moved to different parts of the belt. Has anybody experienced this before. Any ideas would be greatly appreciated.
Pete
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Old 10-27-2004, 02:47 AM   #2
Storm
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If this is anything like what I'm now going through.....I hate to even admit it.... check the pulley bolts and make sure they're torqued. evidently I fogot to due this during my rebuild and the belt/pulley was smacking the cover. I didn't figure it out until the belt walked up over the edges of the pulleys, damaging it and slipping a few teeth. It caused the car to suddenly change tune (phish-phish-phish) and die.

I only hope there's no valve damage......for either of us.

Check those bolts to eliminate that end. Then focus on the tensioner.

Good luck!
Jay Storm
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Old 10-27-2004, 12:13 PM   #3
Honkey3k
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When I did my headgasket, on my 98 Outback 2.5DOHC... I also replaced the shortblock. I had somebody else do my timeing, a friend of mine who worked at the dealer for some time... he had it on their in about 20 minutes. I would say, if you dont know what you are doing, dont do it yourself . With close tolerance motors, you could really hurt something.

Anyways, I cant imgine there being enough slack in the belt to move around, unless... The belt isnt the right size for the motor, you didnt wrap the belt around right or something along those lines. If you are certain its the belt, I would say check the tensior and tensioner pulley, the hydrolic arm thing in the tensioner can break VERY easily... check and make sure its putting a great amount of pressure on the tensioner pulley.
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Old 10-28-2004, 01:38 AM   #4
chip4761
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I would say check the tensioner again. I don't know what kind of tensioner system that engine uses, but in mine, it's a little piston thing the presses on a metal tab in the tensioner pulley. It was hard to compress with a bench vise. REAL hard. If you can move it with your hands, it probably needs replacing.
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Old 10-28-2004, 01:46 AM   #5
Storm
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The trick to compressing the tensioner is to go slowly. I think I gave my vise about 1/8turn over 30sec or so. The slower you compress it, the easier it is.
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Originally Posted by chip4761
I would say check the tensioner again. I don't know what kind of tensioner system that engine uses, but in mine, it's a little piston thing the presses on a metal tab in the tensioner pulley. It was hard to compress with a bench vise. REAL hard. If you can move it with your hands, it probably needs replacing.
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Old 10-28-2004, 09:57 PM   #6
ilmaestro
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Quote:
Originally Posted by Storm
The trick to compressing the tensioner is to go slowly. I think I gave my vise about 1/8turn over 30sec or so. The slower you compress it, the easier it is.


Jay Storm
Yes yes. I didn't want to say this, but if you're sure you had the right belt, I'd say your tensioner might simply be bad. I don't think it's uncommon as many mechanics recommend replacing the tensioner when you do the belt. As Jay noted, the subaru tech docs state that you should compress the tensioner slowly over the course of at least 3 minutes if you plan to use it again.

j
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Old 10-29-2004, 03:59 PM   #7
ImprezaVA
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After you pull the 2mm allen key out of the tensioner, don't forget to rotate the belt via the crank bolt. Just rotate the belt back and forth a couple of times to let the tensioner rod/piston fully release.

I second the tensioner being the problem, but if you didn't tighten the cam sprockets down, torque those to 58 ft-lb.

-Charles-
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Old 10-29-2004, 07:54 PM   #8
dreaminsubys
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Thanks for all the great replies. It turned out to be the tensioner. After putting the new one in and lining up all the marks (was much easier to do the first time when the engine was out of the car) it runs like a champ. Valve train is also much quieter after being adjusted. Thanks again.
Pete
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Old 10-29-2004, 09:18 PM   #9
chip4761
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Yay!! I answered a question correctly!! Yay!!
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Old 11-01-2004, 01:43 AM   #10
Storm
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Glad to hear it's running fine now!

Jay Storm
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