loud knock possible timing belt tensioner

[dharrison]

i just recently purchased my second dsm. it is a 97 gsx with minor work done. it only has 70,000 miles on it and it has very quickly developed a loud knock in or close to the drivers side of the engine compartment (sounds like a full on rod knock). i have been running only 1-2 pounds of boost on account of a cracked turbo and don't know if that has an affect. i have drained the oil, done a compression test and everything looks good, no trash in the oil, compression was all around 150. also, it started at a slight knock at around 2000 rpm's and got a lot worse within a mile of where it started. it also has tremendous power loss my question is what could it be, all i have narrowed it down to was a timing belt tensioner but once again i am somewhat ignorrant as to what that would sond like. if it is that i would be happy to know that's whats wrong. at this point i need to know how to tell for sure if it is a timing belt tensioner.
on another note how hard is it to replace these tensioners, will i have to pull the motor or can i do it in the car?? ]

please help me out if ya can.

 

[bartels903]

On a 1g, you can pull it out pretty easily. Now on a 2g it might be hard, not an idea.

 

[boosted_91_tsi]

The tensioner can be replaced while in the car, but you have very little room to work with.
I had the same kind of noise and thought it was the tensioner. Took it all apart and put on new pulleys, TB, and tensioner. The noise was still there. My next step was to pull the oil pan and inside I found this...

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...I thought for sure it was rod knock at first but it turns out I spun a balance shaft bearing and the rear shaft had about 1/8 in. play causing it to knock around. When I drained the oil, I didnt see any trash come out either. I ended up removing the balance shafts and installing a kit and it fixed the problem. Just an idea.

 

[dharrison]

where are the balance shafts located??

 

[boosted_91_tsi]

They are located in the block. Never hurts to try the easier thing first though. You should be able to do the tensioner by following certain steps in the timing belt VFAQ for info.

If you are going in there, might as well do it all... TB, pulleys, tensioner, and if you feel up to it the balance shaft removal. All of which can be done with the engine in the car.

 

[dharrison]

would you say factory replacement timing parts? also where can i find a balance shaft removal kit?

 

[B0OST]

I say if your going to replace them, go with aftermarket. This way you sleep better at night

 

[boosted_91_tsi]

I use the factory parts, especially for the belts. All the info can be found at www.vfaq.com .... just look under the engine heading.

 

[FORMONTOYA]

I agree, timing belt components are OEM on my car as well. The balance shaft eliminator kit can be found at just about any of our vendors.

I'll also agree, if you're going in there and you don't know when the timing belt was last changed:

TB, idler pulley, tensioner, TB tensioner pulley, water pump, 4 seals (2 cam seals, oil pump seal, crank seal). The balance shaft eliminator should have the needed components to get the job done, just double check that it comes with the seal or if you need to get that one also.

Timing belt job can be done with the motor in the car. I've not done the BS elimination, but have read mixed reviews on doing it while the motor's in.

 

[dharrison]

is there any way of knowing by looking at the tensioners if they are bad? the reason i ask it they look perfectly normal and seem to be spinning on a direct axis of what they should be.

 

[boosted_91_tsi]

The auto tensioner ...

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...should look dry. Maybe dirty but no fluid leaking from it. It is a good idea to go ahead and replace the tensioner pulleys while the belt is off. Although they may not be bad it can’t hurt to replace them now. The reason for all of this is if you are going in to do the tensioner, might as well do everything so you don’t have to go back later to pull apart the parts you put on to fix something beyond that. I recently did the removal with the engine in the car and it wasn’t too easy. The only bad part about it is the limited space to work in. All of the things mentioned here on this thread are potential problems with age and it would be best to fix it before it becomes a problem.

 

[Fabian972]

The auto tensioner ...

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...should look dry. Maybe dirty but no fluid leaking from it. It is a good idea to go ahead and replace the tensioner pulleys while the belt is off. Although they may not be bad it can’t hurt to replace them now. The reason for all of this is if you are going in to do the tensioner, might as well do everything so you don’t have to go back later to pull apart the parts you put on to fix something beyond that. I recently did the removal with the engine in the car and it wasn’t too easy. The only bad part about it is the limited space to work in. All of the things mentioned here on this thread are potential problems with age and it would be best to fix it before it becomes a problem.

How much does a job like that cost to fix tensioner or a spun balance shaft bearing ?

 

[dharrison]

are the 1g timing belt patterns and 2g timing belt patterns different? because mine looks slightly different than that

 

[boosted_91_tsi]

I believe there is a slight difference between the 6 bolt and 7 bolt motors. I spent around 100 total for parts and varoius things for my balance shaft removal. I did all of the work myself. I can not remember what the cost of the tensioner was, I want to say like 65-70. So around 150 for the tensioner, belts, idler and tensioner pulley...IF you need to replace them. If you have quite a few miles on the car or do not know when the belts were last changed then it would be a good idea to do.

 

[dharrison]

is it as easy as pulling those two bolts and takin it out or is there more to it. also should i just go to the dealership for the parts or is it possible to get them in any store?

 

[boosted_91_tsi]

For the factory parts you will have to go to a dealer or order from one who sponsers the site and you may get a little bit of a discount. The two bolts are all that hold the tensioner on. Just follow the timing belt faq. After you release tension with the tensioner pulley and get the belt off, just swap out the auto tensioner, pretty easy to do.

 

[perley03]

Quick question. My motor is doing the same noise, so I'm going to change the TB and the pullies and auto tensioner. I was also thinking about doing the BS eliminator kit. Do the balance shafts have to be removed or can you run the engine with them still in the block, without a belt driving them?? I really dont want to pull the engine but if I have to im gonna do the BS eliminator kit and will pull them out. Never really understood why you have to remove them instead of leaving them in the block. Sorry if I sound stuipid.

 

[boosted_91_tsi]

I dont think there is such a thing as a stupid question. How else would you learn if you didnt ask.

You must at least remove the rear shaft as it is driven off the oil pump. Just cutting the belt would keep the front shaft in the block and keep it from rotating but the rear would still be spinning with the oil pump. I say if you do the elimination, do both shafts. The front shaft can be left in the block and the rear only removed. I dont see this being any problem but if you are in there, might as well do them both. I removed both of mine with the engine still in the car. It was a PITA, but I figure I might as well do it right. If you can remove the engine, by all means go for it as it will make things a whole lot easier.

 

[perley03]

Oh ok I didn't know the rear was driven by the oil pump. Thats why you need to buy new gaskets when you do this. Ok, I guess i'm gonna pull the motor and tranny and do it that way. I got a few broken exhaust mani studs that i got to get out plus i can put my new clutch in as well. Thanks for the info, and wish me good luck as I am having the same noise issue and hope to get it solved.

 

[perley03]

Another question.....why does the BSEK come with new bearings if you are taking the shafts out???

 

[boosted_91_tsi]

Good luck to you. The bearings are for the front shaft. There are holes in the bearings where the oil is fed through the block to the shaft. You must block off the holes using the new bearing and making sure the holes DO NOT line up. This will block off the flow of oil and increase oil pressure. The old bearings may be used if removed carefully and rotated to block it off.

 

[perley03]

Ok, I got it now. I just didnt know why they would send you bearings when you are taking the shafts out to begin with. But now I understand. Thanks for the help.
Shawn

 

[Fabian972]

Does Rod knock cause you check engine light to come on i have knock coming out of my 98 rs with less than 20k on the motor? "rebulit"