Timing belt deflection

[tompumped]

I just checked my timing belt the other day and when I pulled the top cover off, there was about 3/4" of deflection. I just read through some posts. In sdpatts post it said I can take off a panel to access the tensioner, but it said nothing about using an allen key to tighten the tensioner then lock which I thought was kind of odd.
The engine has 100k on it, should I just reset the tension on the timing belt and forget about it for now. It isn't the original belt and the water pump appears to be changed along with the cps. thanks

 

[tompumped]

"After engine has been assembled and run:
If you have a 3.0L, you can retension the belt by the procedure I mentioned in the earlier post. Take off the small door, loosen the 14mm nut, rotate the crankshaft to the yellow mark at the "0" degree index, retighten the 14mm nut and reinstall the door. "

Should I just follow that procedure, or do a front 60k because they never tensioned the belt right.

 

[93rev2sev]

the belt is cogged so as long as it didn't skip a tooth, you can retension it. You will need to rotate the tensioner with the allen wrench, tension the belt, tighten the nut, rotate the engine and recheck the tension.

 

[Mr Anonymous]

In sdpatts post it said I can take off a panel to access the tensioner, but it said nothing about using an allen key to tighten the tensioner then lock which I thought was kind of odd.

That's because you are re-tensioning the belt, not installing a new belt.

Unless you're replacing the belt, unloading and reloading the tensioner by using the allen key is not necessary; just loosen the nut, rotate the motor and tighten the nut. That's all there is to it, you don't actually "put" tension on the belt, with the nut loosened the tensioner spring just pushes the pulley to take up slack and apply tension.

 

[93rev2sev]

I usually help the spring, just to be sure it didn't stick. I don't crank on the pully and force it into the belt.

 

[tompumped]

Thank you guys, I know my crank seal is leaking but for now i'll just do that. I would replace everything but since it's not the original parts i'll leave it for now, and do the top 60k.

 

[tompumped]

I just went out and did the procedure.
I felt the spring tension on the tensioner and i'd think it should be tighter, but I don't know. I was tempted to try and put some tension on it then tighten but I didn't.
I guess the only way i'll know if it worked is to remove the upper timing cover again.
One more question how much deflection is acceptable and does the engine have to be in a certain position?

 

[93rev2sev]

The trick is to to rotate the engine so that all the slack is on the tensioner side of the belt and then take up that slack with the tensionser. It also helps if the rear cam is being held so that you can snug up the "front" of the belt to ensure ALL the slack is between the rear cam and the crank.

 

[sdpatt]

NOTE: The upper timing cover must be removed to perform this check. If the index marks on the sprockets are near the bottom, rotate the damper another revolution.

The greatest tension on the timing belt is when the crankshaft is 60 degrees before top dead center (BTDC) on the No. 1 cylinder. This is when the yellow mark (1st index groove) on the damper is aligned with the 0 degree line on the lower timing belt cover scale and the index marks on the camshaft sprockets are 30 degrees from 12:00, or at about 10:00. The tension between the camshaft sprockets should be significant and the belt should be tight enough so that a firm press from a finger can only deflect the belt about 0.1". It should be like a guitar string.

[Added later] It is at this condition (60 degrees BTDC) where you can open the access port in the lower timing belt cover, loosen the 14mm nut on the tensioner pulley, allow the spring to take up any slack in the the belt, retension the nut to 35 lb-ft (IIRC) and reinstall the access port. If this is done at times (how many, I do not know) over the 60,000 mile lifetime of the belt, it should theoretically last the 100,000-mile interval of the 3.2L engine with its constant tension arrangement which uses the exact same belt.

Then rotate the damper an additional 60 degrees so that the white index groove (0 degrees BTDC on No. 1 cylinder) is aligned with the 0 degree line on the lower timing cover scale. The index marks on the camshaft sprockets should be aligned with the raised ridge on the metal backplate behind the cam sprockets at 12:00. Disregard the white lines on the belt - they are helpful only when first installing a belt.

 

[Racer X]

I usually help the spring, just to be sure it didn't stick. I don't crank on the pully and force it into the belt.

Don't do this, unless your spring is broken or missing or something.

Overtensioning the timing belt can significantly shorten it's life, leading to premature failure.

 

[93rev2sev]

Don't do this, unless your spring is broken or missing or something.

Overtensioning the timing belt can significantly shorten it's life, leading to premature failure.

I agree, don't force the tensioner into the belt. By the time you tighten the hold down nut, the only thing pushing against the belt should be the spring.

 

[tompumped]

I appreciate the responses, it helps ease my mind.
I'm more worried about doing things the right way then i've ever been, and I don't want to jump time. Then possibly bend a valve because of carbon buildup.
If I had the money right now I would've just replaced everything and been done with it, but I trust the belt if it's not the original.
Thank you Patt for explaining in detail, no way to mess up now. I never would've known about checking the other timing marks. I will do that on Wednesday hopefully it takes up all the slack, but that spring felt a little weak.

 

[Mr Anonymous]

I usually help the spring, just to be sure it didn't stick. I don't crank on the pully and force it into the belt.

Don't do this, unless your spring is broken or missing or something.

Overtensioning the timing belt can significantly shorten it's life, leading to premature failure.

Exactly, and over-tensioning the timing belt by doing so is the primary cause for premature timing belt failure.

The greatest tension on the timing belt is when the crankshaft is 60 degrees before top dead center (BTDC) on the No. 1 cylinder. This is when the yellow mark (1st index groove) on the damper is aligned with the 0 degree line on the lower timing belt cover scale and the index marks on the camshaft sprockets are 30 degrees from 12:00, or at about 10:00. The tension between the camshaft sprockets should be significant and the belt should be tight enough so that a firm press from a finger can only deflect the belt about 0.1". It should be like a guitar string.

Scott is exactly right. There's a reason that yellow mark is on the crank pulley!

I'm more worried about doing things the right way then i've ever been, and I don't want to jump time. Then possibly bend a valve because of carbon buildup.

If I had the money right now I would've just replaced everything and been done with it, but I trust the belt if it's not the original.
Thank you Patt for explaining in detail, no way to mess up now. I never would've known about checking the other timing marks. I will do that on Wednesday hopefully it takes up all the slack, but that spring felt a little weak.

Stop worrying.

These motors are almost idiot-proof and not nearly as prone to disaster as you might think reading other posts. Just follow the tensioning procedure and you'll be fine. Jumping time is a pretty rare occurrence. Just enjoy the car and keep on top of maintenance!

 

[sdpatt]

Here is the link to the topic where I posted the timing belt alignment pictures.

 

[tompumped]

I didn't expect this many responses, thanks. It's also good to see that you are still here Patt. I remember 7 years ago when I had my first car which was a SHO you helped me out. Then I knew nothing, i've come a long way since then.
I guess i'm just worrying too much because I need the car to get to work, otherwise I would just jump in and hope for the best. I built a reliable high horsepower engine and drivetrain in an F body. I have no idea why i'm worried.
One more question it seems that most people from what i've read found no valves out of spec when they did the 60k service is this true from what you guys have seen. I think the oil was changed regularly from the looks of the old rod bearings.
I should really just sell the car and get one with less rust, but i'm an idiot.

 

[sdpatt]

It is recommended to check the valve gaps every 60,000 miles. Having performed six 60Ks on my own car, I have learned that there is no guarantee that all valve gaps will remain in spec. The last two services on my car found only 1-2 at the limit of the allowed range, but none over the limit. Since the gaps on my engine have been quite consistent, the oil has been changed religiously and I have no leaks in the spark plug wells, I am considering to skip the gapping service at the now due service. The plugs were replaced and the plug wires don't show signs of grounding, so I will try to make it until the next 60K interval at 440,000 miles. Be aware though, that it is a risk one takes to skip the recommended service.

Scott

 

[tompumped]

I went out to do the procedure the right way this time, and when I opened the cover I saw a small tear in the timing belt. I just ordered basically everything from rockauto to do the front 60k. I was going to order it from RCM, but $60 shipping was steep.
I guess i'm going to use national cam seals and crank seal with anaerobic sealer, I might get ford ones if I can make it there before they close.

 

[tompumped]

Mr.Anonymous after reading your post I decided to use the 1213n seals, only problem I ordered the timken ones. They should be the same dimensions if they are the same number.
My question have you ever used the crank seal part number 710220. I'm not sure if I should use that or get the ford one.

 

[Mr Anonymous]

Mr.Anonymous after reading your post I decided to use the 1213n seals, only problem I ordered the timken ones. They should be the same dimensions if they are the same number.
My question have you ever used the crank seal part number 710220. I'm not sure if I should use that or get the ford one.

Timken/National, they're the same company.

The 710220 works fine. The Fel-Pro seal is the problematic one.

 

[sdpatt]

Yes, the National 710220 is the exact match for the OEM part that I removed during the first front end 60K on my car. I have always used the Fel-Pro TCS45870 camshaft seal set which very closely resembled the OEM parts. The crank seal is covered with a rubber finish and no sealer should be used. I do not recall the need or use of any sealer with the cam seals either as the Fel-Pro set was also rubber covered.