Why Did My Brand New Timing Tensioner Fail (twice)??? Please Help

[rabenne]

ok well my setup is listed in my profile. I have a brand new stroker with timing belt nightmares.

I timed the car with all new parts with the engine out of the car. after running the car for about 400 miles my timing tensioner failed. to be perfectly clear the tensiner sagged down, allowing the tension arm to hit the tensioner body. I bought a new oem tensioner from slowboy and put it on yesterday. Today at lunch I was checking my car for leaks and realised that the tensioner had failed again. This is with less than 20 miles on it.

I am really lost on this one... I have done half a dozen sucessful dsm timing belt jobs, and I always check my work when im done. The tensioner held over night and was still in spec in the morning.


Please help

 

[rabenne]

I have a fresh engine in the car and have ran it about 600 miles or so. I origionally put on all new timing components. I used a gates racing timing belt. I used all oem parts. Everything was going great until about a week ago the car was running funny so I popped the hood to find a loose timing belt.

for clarification the pushrod sunk into the body allowing the belt to loosen.

so this weekend I replaced the auto tensioner with a brand new oem unit from slowboy. I set the belt tension as I always have on both of my cars. I checked the tensioner after taking a 30 min or so break to eat and the pin still moved in and out of the tensioner body and rod freely. The very next day, some 30 or so miles later the tensioner (brand new, 2nd one) has sunk into the body again.

I am ordering a new tensioner, but want to have some idea of what the cause is before I slap a 3rd $87 part on it. ANY help or suggestions welcome.

 

[prostreetdsmx1]

can you send me one of the parts that you're saying failed so we can check it out?

 

[redyute1]

Wow thats a first for me talk about bad luck,but was there any signs of oil leaking around the shaft,before and after they failed.I'm just asking but i really don't have the simplest idea why they would do that unless the hydraulic fluid leaked out.

 

[lccynmbr13]

So you're positive that the 2 holes on the tensioner pulley are about horizontal and the grenade pin can be easily inserted/pulled out before and after you torque everything down and cycle the engine? Any way you can take a picture of the entire timing belt side of the engine with the tensioner and pulleys in the pic?

 

[luv2rallye]

Go with the Mitsu factory one, they are most reliable. You didn't compress the pin too quickly did you? Look here: http://www.dsmtuners.com/forums/art...5-timing-belt-tensioning-tips-4g63-turbo.html

 

[rabenne]

thanks for the replies guys. For prostreet. I definately can, and will. please let me know how to work that out. there is no signs of leakage.

as for compressing it too quickly, the only time I compressed it even a tiny bit was to swap the pin to the correct side.

Does anybody know why the lock pin in both tensioners was fed through the tensioner the wrong way? I had to put it in a vice to hold it while I inserted it through the correct side.

To my understanding slowboy sells the oem one. That is what I have used both times.

Thanks a lot for your help guys, I will be tearing down the car tonight. Please keep guessing!!

 

[rabenne]

I will try to do that with my phone today, THANKS A LOT FOR YOUR TIME

 

[MidShipCivic]

That's a coincidence has to be if that's the case I would start getting it at the dealer to be sure you're getting something that's coming from Mitsubishi. Since dealers have private couriers that come on a set day to bring factory parts in.

 

[rabenne]

then tensioner at no point showed any signs of leaking. after discussing this with some people I realised that the tensioner was not an oem one. I purchased it as if it was, but for some reason, when i came, its an aftermarket tensioner.

I have another tensioner here with less than 5k miles, which i will try today.

As for the oem unit being the most reliable. I have read that for a long time on various forums, but a very well known builder (very well known) told me today that he has seen more oem ones fail than aftermarket units.

If my belt were set too tight via the tension adjuster pulley wouldnt the rod compress while being turned over by hand before checking after 15 mins? I gave it well over 15 minutes to settle after turning the engine over 6 times. The rod went in perfectly smooth, with as little restriction as possibly imagineable. As far as I know, the belt tension was perfect before being started.


thanks again guys!

 

[TrevorS]

FWIW -- I'm on my third OE tensioner, but that's only because they seem to reliably start leaking by the time the next 60K belt install rolls round.

 

[rabenne]

I am jealous, this will be my third and i havent hit the first service intreval. Turns out slowboy accidentally sent me aftermarket, non oem parts both times. They have agreed to send me out the oem one I paid for, so at this point, the only thing i know to do would be try it and see. I will try using the torque wrench method rather than the pin alignment method. ANY other suggestions welcome


the only thing im concerned with is that I do not have the timing tins that mount between the front engine mount and the block. This makes the tensioner arm, tensioner, and tension pulley a hair closer to the block. The pushrod still hits the tension arm solid, but not directly centered when considering distance away from block.

 

[TrevorS]

I am jealous, this will be my third and i havent hit the first service intreval. Turns out slowboy accidentally sent me aftermarket, non oem parts both times. They have agreed to send me out the oem one I paid for, so at this point, the only thing i know to do would be try it and see.

Darn -- that really sucks, but at least there's good reason to believe the next will be good. Good luck !

 

[rabenne]

well the fact that they are aftermarket alone does not necessarily mean that they failed for that reason. I would like to think that even the cheapo slowboy substituted in my order would hold up longer than 30 miles

I really struggle with the fact that the tensioners had the grenade pin inserted from the wrong side. Its almost as if the tensioner was packaged for another model. I know this tensioner was used on some hyundais, but i cant imagine any differece. if anybody knows anything about those hyundais let me know.

please give me some things to check. I will pull the tensioner tomorrow. and post any findings.

 

[EGuenther]

I have been having the same issue, any hydraulic tensioner I put in fails in short order. I think mainly to blame is me not following the instructions exactly. Next time around, which is soon, I'll do it more precisely Just curious, did yours make a ticking sound, kinda like lifter tick, when they crapped out?

 

[rabenne]

yeah it did kinda make a clicking sound, but I have not been able to diagnose that as the noise. I think its the tensioner arm hitting the auto tensioner body... please let me know what you figure out

 

[MidShipCivic]

I am jealous, this will be my third and i havent hit the first service intreval. Turns out slowboy accidentally sent me aftermarket, non oem parts both times. They have agreed to send me out the oem one I paid for, so at this point, the only thing i know to do would be try it and see. I will try using the torque wrench method rather than the pin alignment method. ANY other suggestions welcome

I said this in your other thread glad you found your problem

That's a coincidence has to be if that's the case I would start getting it at the dealer to be sure you're getting something that's coming from Mitsubishi. Since dealers have private couriers that come on a set day to bring factory parts in.

 

[rabenne]

well im not sure if I have solved it yet. I am waiting on an oem tensioner from slowboy, they are paying for next day but they only get parts at mitsu on thrusdays so it may be as soon as friday, but likely later, that I will be trying again.

if i burn out the oem one in an equally short fashion, i plan on ordering a BLE solid tensioner. this is not my daily driver, its a joy toy i play with on the weekends. I can manage the belt adjustments as I keep a close close eye on my timing belt anyhow. Ill just measure the belt deflection on my 90 laser at a designated point, and match my talon as closely as possible with the solid tensioner.

hey eric, curious as to what cam sprokets you are using, and also, what type of timing belt?
I replaced the timing belt with the 2nd auto tensioner due to oil contamination. I fixed the leak and replaced it with the same model gates racing belt. I am using a brand new crank sproket and the oil pump and sproket are only 500 or so miles old as well.

I got my hands on some timing tins, and plan to install them when the new tensioner comes.

 

[MidShipCivic]

well im not sure if I have solved it yet. I am waiting on an oem tensioner from slowboy, they are paying for next day but they only get parts at mitsu on thrusdays so it may be as soon as friday, but likely later, that I will be trying again.

if i burn out the oem one in an equally short fashion, i plan on ordering a BLE solid tensioner. this is not my daily driver, its a joy toy i play with on the weekends. I can manage the belt adjustments as I keep a close close eye on my timing belt anyhow. Ill just measure the belt deflection on my 90 laser at a designated point, and match my talon as closely as possible with the solid tensioner.

I wouldn't do it, (manual tensioner) I'd have to say what's happening to you is a coincidence.

 

[diambo4life]

Hate to say it but this sounds like user error.

 

[CREEP]

Did a search here and caught your thread. This has recently happened to me too. Mine lasted all of 3 months. I got it from ExtremePsi (which is a great company!..not bashing, just for reference.) I noticed slack in the belt between the cam gears and figured the tensioner arm must have been worn through. Nope..took up some tension from the belt with the "special tool"/battery tie down and it never came back. Hoping to have better luck with the next one and wish you the best too!

 

[rabenne]

I am open to the idea of user error, but I still have no evidence of it. What did I do incorrecty? If I over tightened it then wouldnt it have caused the pushrod to sink into the tensioenr body while I was waiting for it to settle, before checking it....

What type of errors would cause this problem? user errors included

 

[jdd1231]

Well you are assuming its bad because the plunger sunk inside,causing the tensioner arm to hit the body of the hydraulic tensioner,correct?

Over tightening the belt will cause this to,no?

 

[diambo4life]

Can you walk us through on how you set your timing belt tension. Hydraulic adjuster and there's a tensioner pulley. Please don't use those interchangably and it confuses some of us trying to follow what you are talking about. I guarantee you there's a flaw in your methodology somewhere. We just need to find out what it is.

 

[rabenne]

To set the timing belt tension I start by routing the belt, ensuring there is no slack between any sprockets except on the tensioner pulley side. I then use a 1/4" ratchet and the miller tensioner pulley tool and apply just enough force to the pulley to allow the grenade pin on the auto tensioner to loosen up. At this point of tension, I turn the tensioner pulley bolt to torque spec 29-36 ft. lbs, I think i ended up at 33.

After setting the tension in this manner I pull out the grenade pin and waited about a half hour after rotating the crank 6 times. At this point I checked the tension by re-inserting the grenade pin into the tensioner body and making sure it moves freely inside the body and pushrod.


I hope this is clear enough, but then again I dont see where I "interchanged" any terms.

I agree 100% that an over tightened belt would cause a sagging auto tensioner, but I have done several other timing jobs, and never had a problem when setting tension this way. If there is a step I am missing, drop me a line.