My car keeps jumping timing

[bojanglesracing]

Ok my car has jumped timing 3 times now. So in fear that something had to of broke I pull the head off. For some reason there is nothing bent or broke no marks no signs of valve hitting the pistons. Now why does my car keep junping time? And why did it not hurt anything? The last time it did it it was out by 2 and a half teeth. So if anyone has any ideas please let me know.

 

[GVR4592]

Are you using all new parts? Who's doing your timing belts?

 

[bojanglesracing]

I am and yes the belt i put on the first time only had 500 miles. When it jump I used the same belt, then when it jump again I got a new one and put that on and it was fine for a2 weeks then it jump again.

 

[prplhz96]

like he said, did you use new parts??????Sounds like to me as if you are reusing the same "bad" hydraulic tensioner, or you are not setting the belt at the right tension.

 

[blue92laser]

maybe i have a solution....first - 2 teeth arent gonna bend valves, its when it jumps way out...

the reason it may keep jumping is due to the accentric tensioner driving the timing belt. This tension is the round one attached to the hydraulic tensioner assembly. If the 2 pin holes arent straight up...or pretty close to straight up. Straight up, of course I mean if it is over top of the center bolt holding the pulley onto the hydraulic tensioner assembly. If IT IS NOT OVER TOP - the timing belt stretches of a period of time and will become even looser if that tensioner isnt centered right.

Let me know what you find out...

 

[GVR4592]

You need to replace all of the timing components and get the proper tools to adjust the tension. It sounds like you have some worn out components or you just aren't setting the tension correctly.

http://www.vfaq.com/mods/Tbelt-checklist-pre.html
http://www.vfaq.com/mods/Tbelt-checklist-rem.html
http://www.vfaq.com/mods/Tbelt-checklist-inst.html

 

[bojanglesracing]

Well it all apart now. Going to do bse and replace the oil pump so when it go back together I will look in to that. Thanks for the help.

 

[jo_91gs]

also, if the timing components are still in good condition (hydraulic tensioner, pulleys, belt especially) and it still jumping, then you might be overlooking some of the directions from the book. i tell u that from experience, for instance the oil pump sprocket must be set synched to the other pulleys (cam, crank) but with the weight of balance shaft at the bottom of the sprocket. it is very obvious when the weight of the oil pump sprocket is down or up if you are turning it by hand. and after you have completed installing all components of the timing and the belt still feels that it has too much slack, there might be a chance that the tensioner adjuster pulley is not being tightened properly. again these steps might have been overlooked and it might be possible that your components are still good and if installed properly your timing will be set. hope any info helps....

 

[toybreaker]

I've seen a couple of motors jump time.

When I took them apart to investigate, I found the tensioner was wound the wrong way. It's possible to get the correct~ish tension by going counterclockwise, but you get less wrap around the intake cam.

The tensioner arm needs to move freely. Have you dissassembled and lubricated it's pivot?
Make sure there's not a dimple on the arm where the tensioner pin hits it.

Try wrapping the tensioner clockwise this time and set it where you want it.

Pull the tensioner pin.

Rotate the motor a few times, wait approximately two beers, and then check the tensioner pin protrusion. In a perfect world, you could reinsert the pin. If it's close, you're probably good to go.

Also, the best t-belts for these cars come from mitsubishi. I strongly reccomend you use factory timing components, if for no other reason to eliminate a variable from your problem.

 

[ErichMoraga]

... the oil pump sprocket must be set synched to the other pulleys (cam, crank)...

That's one reason it's nice to go with a balance shaft eliminator kit.

-Erich