aaddpp

Hi all,

What weight oil does the stock timing belt tensioner take? And what volume?

Thanks
Dave

Mrmerlin

if you click on the User CP at the top of the page,
then click on edit signature,
you can then add your car info to every post you make
Anyway to answer your question this depends on how often you want to refill it. If you have put on a new boot and new clamps then eventually the oil will run out, the WSM did spec 90 wt at some point then changed it to engine oil.
My suggestion use STP oil treatment .( this type of oil stays thicker and wont run out as easily as the other oils do )
fill up a Visene bottle with the tip drilled out this way you cant blow the clamp off the new boot as you can with a hand held pump,
The fill hole is the one closest to the passenger fender or furthest away from the crank.
Remove both of the nipples or plugs from the tensioner prior to filling

Cosmo Kramer

+1 on this, I used Merlin's method and mine has not leaked a drop!

Landseer

A syringe will also do it.

aaddpp

Thanks, added the signature - hope it works.

Also are you saying to use straight STP Oil Treatment in the tensioner?

Thanks
Dave

Landseer

Its just a heat transfer device.

dr bob

Primary duty of the oil is to provide hydraulic dampening of oscillations at the piston. In the bottom of the assy there is a check-valve that only allows oil to flow into the piston, not out. So the piston can follow the belt tension arm quickly as it moves to take up slack, but compresses very slowly when that tendion arm pushes back some.

Plus it carries block front water passage heat to let the spring washers collapse slightly as the engine grows on warm-up.

Landseer

I can understand it lubricating the bellville washers and I understand the heat transfer.
Wouldn't the system need to hold more pressure to dampen the oscillation?

WallyP

The only pressure that it holds is between the bottom of the piston and the closed end of the housing. The piston slides in the body as the tensioner arm moves. As dr. bob says, as the arm and piston moves to take up slack in the belt, oil can flow freely from the reservoir in the block into the cylinder underneath the piston. As the arm and piston try to move back down to add slack to the belt, the check valve closes, trapping the oil under the piston. The oil can still flow around the piston in the cylinder, so the arm and piston can move in relatively slowly. It acts like a one-way shock absorber to reduce the flutter during belt operation.

If the gasket and boot are properly installed and in good condition, the tensioner will leak very, very little. You just need to top off when you check the belt tension. An annual check is a very good idea...

I use the same oil in the tensioner that I use in the engine.

mark kibort

I think you are giving the "damping" purpose of the oil a little too much credit. I have not run oil in the tensioner in 10 years, and thats a lot of race miles and hours. I did fill it finally with the new stroker, as it was a new block and was able to change that gasket, but turns out, it leaked out, yet again, out of the rubber seal around the shaft. If you have ever taken one of these things apart, there is little or no movement of the shaft when the engine is running. Its not like its a shock absorber. there is such little movement, that the oil is not really doing much of any thing. Lubrication is required, as we had scots all jammed up. (no oil either) and the draw back was that we couldnt get the shaft to come out of the structure when disassembled. however, we could set the tension and it did hold, as jammed up as it was. this was also a combination of the wrong components, which gave a real bad angle of the shaft and the tensioning roller. Point is, there is really no movement in the tensioner wavy washers. think about it, if the expansion rate of the entire washer stack , changes the tension a generous, 1 point on the 9002 tool, that is less than half of a turn on the tightener. Even if it was 1 full turn, the movement that it could move is almost imeasurable, except with a micrometer.
I think its good to have some oil in there for anti corrosive reasons, but thats about it. also, I like using swepco gear oil, because it is green and I dont want to confuse an oil leak with the tensioner leak. (amsoil red or goldish, while swepco gear oil 75-90 is green and easy to see)

The only think you loose without oil, is the ability of the heat to flatten the washers to lesson the tension setting until all the heat is transfered to the system. (means, for a longer while, with no oil, you could be running at a higher tension) thats not such a bad thing, especially that eventually when everything is hot, the washers will flatten and loosen the tension to counteract the engine expansion.

I have never given the missing oil in the tensioner a second thought. there is enough oil residue to keep things from corroding and thats all I care about.

dr bob

Mark, you put a whole lot of faith in 'luck'. I'm happy for you that the luck has been pretty much in your favor so far. But bragging that you haven't been doing even the normal-design maintenance stuff on a car that you race just taxes my ability to understand your thinking. With all the discussion, tedious explanations of how it works, the reasoning, and then the failures and the alarm messages to the dash that others and you have reported, why would you ever decide to pull the sensor switch lead and not to put oil in the tensioner?? Then brag about it like some maroon, trying to justify it as if it's some kind of victory that should be celebrated??


Do you know the story of the guy stranded on his rooftop by the rising floodwaters? A rowboat of RL friends come by to rescue Mark, but he says that he doesn't need the help and that God will save him. As the water rises higher, other friends in a rescue boat come to get him. Again, he refuses the help and says that God will save him. As the water rises to his shoulders as he stands on the peak of the roof, a rescue helicopter comes by but again Mark refuses any help, since God will save him. At the Willowy gates a short while later, Mark has that look of wonder on his face as he asks why God didn't save him. Dr. Porsche looks down and says "I sent a rowboat with a belt to save the motor, a rescue boat with aligment tools and a manual, and then a helicopter with tensioner oil. What kind of help were you expecting??" Mark knew then that what he'd really needed was a new brain, one that looked outward at the bigger picture rather than relying on a sample experience dataset of one, one that understood what RTFM means, one that didn't tempt the mechanical devils on purpose or just depend on dumb luck all the time.

Can anybody guess who it was there on the roof? How long can you tread water??

With some luck, God willl save you.

Toms928

does anyone have pictures of where you check and add oil to the tensioner or a link on rennlist. Thanks

davek9

I have to go with WhallyP on this one Mark, and Whally I have following the same method too.
However I do think that start up temp has a lot to do with it and believe that PorKen has shown this to be true.
So the car sitting in my heated garage is going to “flap” less upon start up then the one sitting in my driveway at 17deg F.

Picture on the way..

Mrmerlin

DaveK. FWIW even though there are nipples on the newer tensioners I would still recommend that you remove both of them when you fill the tensioner.
What can happen is the outlet can be plugged and then with the hand pump you happily pump away.
The part that will give is the rubber boot, and the clamp that will fail is the inner clamp, this will let a burst of oil run down the tensioner and then you will have to remove the belt to refit the inner boot clamp.
So that is why I suggest to use a visene bottle with tip drilled out, after removing both of the nipples, place a rag under the outlet port ( the one closest to the crank) and fill with STP, the visene nipple fits perfectly into the fill port and you can not overpressurize the boot.
I have already had a boot clamp failure while using the hand pump method.
This visene bottle procedure works perfectly .
If you already have engine oil in the tensioner you can add the STP and it will push the old oil out as it seems to float the lighter oil, keep filling till you see the thick stuff coming out of the outlet.

Mrmerlin

BTW the tensioner uses about 3 oz of oil