Timing belt tension????

[85boostbox]

I am having a issue with my timing belt walking off the cam pulley. I have loosened it to the point of where it is slapping around and it still is at the edge. Motor is a 88 BTW. I have seemed to try everything. Any suggestions of what it could be would be greatly appreciated. Thanks in advance.

Paul

[turbovanman²]

You set it so you can just barely twist it 90 deg at the longest part.

[85boostbox]

I have tried that. It still sits at the very edge. Is there a difference inbetween tensioners.

[turbovanman²]

I have tried that. It still sits at the very edge. Is there a difference inbetween tensioners.

Tall decks had smaller ones IIRC but if you getting tension, that isn't your problem. What have you done to it? Maybe the tensionser pulley surface is worn at an angle.

[85boostbox]

I motor swapped this car. It is a 90 Daytona originally 2.5 turbo auto. Now it is a 2.2 Turbo Auto. It has a plastic tensioner on it now. i did check to see if there was any difference between the depths but i didnt see any difference.

[turbovanman²]

It could be the plastic has rolled with time and causing the belt to walk, its been awhile, sorry, but can you turn the tensioner around?

[85boostbox]

It is a brand new tensioner. I think i might have a CB tensioner on there and not a Non-CB tensioner on there. I am goig to switch them tomorrow and see what it does. Will chime in tomorrow to let you know.

[cordes]

It could be the plastic has rolled with time and causing the belt to walk, its been awhile, sorry, but can you turn the tensioner around?

You can't turn the tensioners around. I think there was a difference between the square tooth and round tooth ones, but I think it's slight. That could cause a problem though I guess. IIRC the tall deck tensioners were different in diameter, but I don't know about the spacing off the block.

There is a proper tool for the job which I prefer to use. It's less than $15 shipped these days I believe.

[85boostbox]

If this is the tool your talking about i have it and this is what i used to do tension.

[cordes]

If this is the tool your talking about i have it and this is what i used to do tension.

That's it. I would look at the distance the belt rides off the block with the two different tensioners you have.

[85boostbox]

That is what I am going to do tomorrow. For some reason that is what i think it is. Will find out tomorrow. Also i need to advance the cam 1 tooth figuring that i am off 1 cause this thing has no low end power but it screams above 4K RPMS. Also my gas mileage has sorta sucked too. Will let you guys know what happens.

[cordes]

If you haven't seen it before here is my timing video.

[85boostbox]

I do mine the same way with the flywheel marks. I just usually have a issue with the cam. And i do the same thing with the I-shaft as well. When my motor was put together by the machine shop they put the oil pump and ishaft off 1 notch. So that is really the only way i can get it right LMAO. Thanks for the info and vid though.

[cordes]

No problem. I think I actually put mine back together properly so that anyone who comes along after me won't be pulling their hair out if they try to do it by the book.

[85boostbox]

Yea i found out the hard way LOL. When i first got the car going my distributor was way off. Took me a few to fiure out why cause i was lining it up with the mark on the pulley's. It was only 1 notch off though so it wasnt too bad. As i said i am pretty sure that i am a notch off on the cam though cause this thing is SLOW off the line but it screams past 4K. So when i change the tensioner tomorrow i am going to move the cam advanced 1 tooth.

[JDIZZ]

I had an 87 2.5 tall deck that was trying to walk the belt off the cam pulley and wearing the edge off the belt. It beat my butt for months. I learned that "flat belts travel to the high side of a pulley". I am sure a new set of pulleys would of fixed it, but I was cheap. As this was a flat tooth pulley, I had my friend at the machine shop lathe cut a small amount off the belt area on both pulleys leaving a slight crown in the middle ( /--\ ). Never had another problem. The belt stayed dead center.
So if you have the same problem I had, one or both of your pulleys may of lost it's crown.

[AngelesRunner]

You can't turn the tensioners around. I think there was a difference between the square tooth and round tooth ones, but I think it's slight. That could cause a problem though I guess. IIRC the tall deck tensioners were different in diameter, but I don't know about the spacing off the block.

There is a proper tool for the job which I prefer to use. It's less than $15 shipped these days I believe.

I have 7 Chrysler, Plymouth, Dodges with 2.2L or 2.5L fours. Where do I get the timing belt tensioner tool?

I've done 4 valve jobs and I use the twist it 90 degree method but the belt on the 92 Acclaim is flopping a bit and hitting the top belt guard so I had to remove the guard temporarily. I would like to tension it properly when I get to work on it.

[cordes]

Here is one for $15 shipped.

http://compare.ebay.com/like/3603957...=sbar&_lwgsi=y

[4 l-bodies]

There is a depth difference between CB and non common block tensioners. The CB is taller which will make the belt ride on the outside edge of pulley. Pic says a thousand words sometimes.
Todd

[ScottD]

There is a depth difference between CB and non common block tensioners. The CB is taller which will make the belt ride on the outside edge of pulley. Pic says a thousand words sometimes.
Todd

Good pic showing the difference between tensioners!

When setting the timing I use the timing belt cover to locate the cam. The oblong hole should be in the center of the hole in the timing belt cover. The intermediate shaft can also easily slip while you're trying to get all your marks aligned, after the belt is tensioned it doesn't hurt to double and triple check your marks.

Lastly, a new belt will s t r e t c h. When you put a new belt on, always go back and re-check tension after a few hundred miles. I have the tensioner tool mentioned here but find the twist method at the longest part of the belt seems to work better for me on 8 valve cars. On my 16v 2.2, I use a tension gauge to check the belt tension.