How to tension timing and balance belts tooless

[AA_Ezra]

I know alot of you use different techniques and it's allways in a thread that usualy off topic so I thought it would be nice to have here.
The one method one of you recently posted was In regards to the timing belt being tight enough to just move the water pump by hand. And then there is the twist method wich I must have done wrong as my belts were tight.

Please post you're techniques.
I have the arnworx 920x but it's always nice to double check with a diced t method.

And please state weather you can use the technique on a new and used belt..
Thanks
Jaime

[VINMAN]

I use both the twist and W/P method. never had an issue. I have verified both using an Arnworx tool one time. Pretty much dead on.
As I've stated many times before, to me, the whole belt issue is over-paranoia

[vdubr928]

I've gone both ways but bottom line is unless you have a pretty good idea what it should feel like. (Ie not first time with an adjustable tensioner) then you should do it with a bible in one hand. Not that it can't be done with the twist method. I've done it and verified and it was close but that was on a non interference 8v 928 engine. Surely there is a porsche club in town? One of the guys I met had one.

[AA_Ezra]

Nope town is small

Was my description of the watermpump method the way it's done or is there more to it.

I agree vdubr928. I have no auto tensioner so I don't have a feel of it for this car. Funny thing is I have done it on fords and the like just never occured to me to check the tension as the tensioner was still in good shape

[944Larry]

Krikit to start, then belt twist and w/p pulley twist for me.

[AA_Ezra]

So is the water pump pulley supposed to move or not? After using the arnworx tool for a brand new belt it does not budge. Maybe because it's new.

[944Larry]

It should twist on a new belt, not sure about an old one.

[vdubr928]

Too bad you couldn't work somethig out with someone who.has one. Once you use the tool once you can get it super close without one. I don't know if I would go in blind on an interference motor. How much is the tool now? If you are wrong either way its an entirely different but each potentially very expensive (and sometimes block ruining) set of issues. Im sure you know this and im a DIYer but at some point you order the tool. You're going to use it.

[John_AZ]

Originally Posted by AA_Ezra

So is the water pump pulley supposed to move or not? After using the arnworx tool for a brand new belt it does not budge. Maybe because it's new.

The pully, when grabbed with clean fingers on one or two hands depending on your strength, has to move. This is because the engine will expand .0112569 of an inch (or something close ??) when it heats up.

I check the belt twice with the WP method. Each time I rotate the crank 4X clockwise and stop at TDC. The engine has to be cold, at about 68 degrees.

If you cannot turn the WP pully with 2 hands, using thumbs and a couple of fingers on the pully----your belt is too tight.

NOTE A brand new belt must feel tighter than a used belt. The new belt cogs need to settle in the pullys. I check a new belt after about 700 miles. This can be done by just taking the top half of the belt guard off.


You have the great Arnnworx tool, this is a second test to use.





GL
John

[AA_Ezra]

John. You need to do you're own wikipedia :P

This thread is going great. Pc was down for a bit so i could not search the arnworx p920x vs the Porsche p9201 but i remember them both being accurate and the poser leaned toward the Lower tension settings on the arnworxs tool.

It worked great the first time i used it but never got a chance to use it to retention as i had an oil leak that maybe got oil on the belt.

I think the Water pump pulley method wold work but i just realized that my Rebuilt pump was painted in some kind of Aluminum paint including the roller so the surface on the roller is not smooth but has a little texture which i think is enough friction that i can't move the pulley.

Now i don't know weather i should let the paint wear off from use or wet sand it off wich would be a littel tricky when mounting.

I will try one more time when it cools off again. Original tension was done around 64-68 F outside temp in the shade


see my whole pump was painted including the roller

[vdubr928]

Probably standard procedure to paint the pulley. Anyone? My last one was black and smooth though. Looks like they used the same paint for the entire thing. Lame.

[AA_Ezra]

Originally Posted by vdubr928

Probably standard procedure to paint the pulley. Anyone? My last one was black and smooth though. Looks like they used the same paint for the entire thing. Lame.

yes they did and i agree lame. it has the texture of primer

[looneybin]

Visalia is not too far of a road trip from Fresno if you need a hand.
I used the water pump method & had it checked by Sigfrieds (before the fire) and was dead on to their 9201

[vdubr928]

Set it up. Get it close. Run it at idle for five minutes. Burn off the paint then recheck. You wont hurt anything just don't go drive the piss out of it. If you have a pretty good idea what it should feel like you know its not rocket science. It seems like (being smart enough to realize the paint is an issue) you have a pretty good head on your shoulders. Trust yourself.



Use the force luke

[89-944NA]

Twist, pull through 2 revolutions twist again...never had a problem

[Brozoar]

Now, when twisting on a broken-in belt, should it twist a bit more than 90 degrees? I'm guessing yes, since it should now be around 27 +/-3 lbs. of tension (according to Krikit), as opposed to the proper 40 +/-3 libs. for a new belt?

I just need to stop second-guessing myself. =) WP test yields about the same result as a new belt for me, though.

[ernie9944]

Originally Posted by Brozoar

Now, when twisting on a broken-in belt, should it twist a bit more than 90 degrees? I'm guessing yes, since it should now be around 27 +/-3 lbs. of tension (according to Krikit), as opposed to the proper 40 +/-3 libs. for a new belt?

I just need to stop second-guessing myself. =) WP test yields about the same result as a new belt for me, though.

Take a look at the video I just send in on the Tread (944s2)this will answers many of your questions I'm sure.

[SolReaver]

I tension by hand but advise less experienced mechanics to use a tool the first few times to "get the hang of it" a Kricket is reasonably cheap as a starting point. I have discussed this subject so many times....IF you search my posts you will find enough to do the job right. However...I am not responsible for your work or your car. If you are unworthy....you don't deserve the car anyway.

Timing belt happiness
this is the thread where I "named that tune" for less than 100. IOW, I got really lucky. You won't. face it, I am better looking and live cleaner than most. The majority of time you might want to replace more than the belts. How good are you at inspecting the components? and...tools....FW lock, pin spanner, etc.


Check out this thread:

Timing belt help

Just a little service I run for people who haven't gotten the hang of the search function. In case you are too lazy to look at the thread which has nifty pics and discussions and PORN. (Ok, no porn, I just said that to get you interested) here is my insane methodology....

I tension by hand and so do a lot of "old school" mechanics. It can be done. For the first few times I suggest that you use a tensioner tool in order to get a feel for it. The auto tensioner (if so equipped) gets you close, but they are notoriously inaccurate. Hand methods include "twist" WP pulley, Plucking, by ear and whine threshold. (among others) It really depends on your mechanical aptitude and comfort level. I can walk you through it if you like.

CAVEAT: you are on your own...I am NOT responsible...PERIOD. This works for me, but I am not there looking over your shoulder so, I can't be sure you are doing it right. VERY important to rotate the engine TWICE and check the marks if you slip on the tension (if the belt goes slack) as these things skip a tooth a lot during the job. Also, mark your flywheel at the low bell housing with a strip of paint to be sure of TDC without having to use the stupid sight hole at the top.

A LOOSE belt will EAT your Valves (or worse) use extreme caution. a belt that is too tight will kill your water pump in no time flat, again use extreme caution.

IF you have an auto tensioner...use it. It gets you in the ball park. Mark the components and use these settings as your starting point.

It helps to have the sprocket wrench or some other pin type wrench to get the fine adjustment on the auto tensioner. DO NOT lever against the pulley...EVER!

Twist method entails tensioning the belt by twisting it between thumb and forefinger. You should be able to twist the belt to 1/4 turn with little force, 3/8 ths twist with reasonable force and half a twist with strong force at it's longest span.

WP pulley method is when you can just barely turn the WP pulley against the belt tension. If it slips...too loose...If it can't be turned at all...too tight.

Plucking and by ear entails plucking the belt and feeling and listening to the noise it makes and feeling the vibrations that it makes against your finger or thumb as you dampen it. It takes an ear and a feel that a lot of people just don't have.

Whine threshold entails setting the belt tension as best you can using any or all of the above methods and running the engine. A belt that is too tight will "howl" and a belt that is just right will be almost silent when cold and whine a bit when warm. I leave the covers and alternator and PS belt off for these brief run sessions and listen from the drivers seat with the windows up and from the front of the engine. the whine sounds a little like an electric motor that matches the speed of the engine or an alternator that is full fielding.

The bal belt whines as well, you have to set it a bit low to be able to hear the Cam belt correctly, OR be able to isolate the two different sounds. Both belts make a nice harmonious sound when you do it right, kinda like a cross between a whirr and a hum.

It the foregoing makes no sense at all to you, or makes you nervous...pick up a kricket or some other reasonably priced tool, they are really not that expensive and you will be doing the job again in 1000 miles and repeating the whole thing 30K or three years from now anyway, so it is a prudent investment. OK?

[AA_Ezra]

Good to see you're still around Sol Reaver, have seen you post in forever. welcome back :P

[AA_Ezra]

Originally Posted by looneybin

Visalia is not too far of a road trip from Fresno if you need a hand.
I used the water pump method & had it checked by Sigfrieds (before the fire) and was dead on to their 9201

Hey thank's for the offer looneybin, How's the 944 or porsche scene in general over there? I have a local guy here in visalia who has a 944 we talk a few times a year and were supposed to ride with his buddy in a 914 on some civilian run military access road with good twisties but that never paned out.

Update on the belts.

After double checking with the arnworx tool and rotating the engine 2 full turns i was able to move the watter pump pully very snugly. But i might have to do it all over again because i rotated the tentioner roller for the timing belt CLOCKWISE and Not Counte CLOCKWISE as i read in Clark's Garage. But the directiosn for the arnworx tool did show that Clockwise was to add tension and counter clockwise so release tention.
So i don't know now.

I do have a bit of a belt whine. i am asuming its the balance belt as i re-used it but it had about 1-1.5k miles on it. Maybe loosen it a bit as it's already broken in? I will double check with the arnworx tool tomorow morning when the car is cool.

I did have a huge knocking noise upot start up wich i thought was lifter or rod knock... IT was the dang Steering Linkikage hitting the OIl PAN!! good times