Broke timing belt tensioner arm

[j_eclipse96]

I broke the timing belt tensioner arm on my gsx tonight while tightening the special tool to compress the timing belt tensioner.

On this picture, it is simply labelled as "tensioner", and is connected to the tensioner pulley. I was wondering if anyone knew the part number for these or what the "proper" name for them is, so I could order them from the dealer. Thanks.

 

[luv2rallye]

Mitsu calls it the Tensioner Arm. How could you break that? It's solid steel (or at least cast).

 

[perley03]

Just looked it up on CAPS. For your car, its MD130032. Rockville Mitsubishi has one, $21.97, just looked it up.

 

[j_eclipse96]

Alright thanks. Rockville is actually where I ordered all my other timing parts, maybe I should have ordered a tensioner arm too

How could you break that? It's solid steel (or at least cast).

I guess we tightened it down too far. We were trying to compress the tensioner as far as possible, to get the most slack on the belt so we could tension the pulley as tight as possible. When I heard the snap, I was sure it was the bolt tool, but then I saw a piece of the arm on the ground.

We weren't using the special tool (the one to turn the pulley), which was probably a mistake.. So I am ordering one of those, as well as a torque wrench. Shouldn't take long when I get all the parts in, then it will finally be road ready

EDIT: When finished, the pulleys bolt should be almost exactly below the two holes for the special tool, right?

 

[luv2rallye]

You rotate the tensioner pulley counter clockwise so the bolt ends up somewhere between on the right of to above the 2 holes. Here's some other tips:

Timing belt tensioning tips (for 4g63 turbo):

Follow the VFAQ timing belt installation procedure exactly
[for 1g: http://www.vfaq.com/mods/timingbelt-1G.html;
for 2g: http://www.vfaq.com/mods/timingbelt-2G.html;
for home made tensioner: http://www.vfaq.com/mods/timingbeltNOTE1.html ]
with the following tips:

Replace the auto tensioner with new factory one if it is leaking (no after market or you will regret it). And when you compress it to put the holding pin in (eg. 1/16" allen wrench), compress it VERY, VERY, VERY slowly (like steps of: 1/2 turn of vise handle, then wait 20 seconds for it to settle, repeat) or you will damage the seals in the new one.

NOTE: THE EXHAUST CAMSHAFT SPROCKET MAY ROTATE IN THE COUNTERCLOCKWISE DIRECTION AS THE BELT IS TENSIONED. THIS SHOULD BE CONSIDERED WHEN INSTALLING THE TIMING BELT. If the camshaft sprocket timing marks don't line up after tensioning the belt with all the other timing marks lined up, loosen the belt and retension it, but try rotating the exhaust sprocket slightly clockwise (1 tooth off) first.

Sometimes measuring the distance between the tensioner arm and auto tensioner body (usually with a drill bit) is hard to see or do. Example: Can't get in there or see if drill bit is truly parallel to the tensioner top (which affects measurement) or you can't get a 2.6 ft-lb torque wrench on the tensioner pulley special tool #MLR-MD-998767. You can replace all that complicated tensioning torque stuff (which you can rarely get right with the engine in the car anyway - no room) with the following alternative. Just adjust the tensioner pulley so that the auto tensioner holding pin (eg. 1/16" allen wrench) moves freely all the way through the auto tensioner body and pin holes (after you turn the crankshaft and wait for the belt to stretch and auto tensioner to settle). Adjust the tensioner pulley to do this and it will automatically make the distance between the tensioner arm and auto tensioner body (drill bit measurement) be about .157 in. (spec is .150 - .177 in.). I've done over a dozen dsm TB's this way every one done correctly.

You don't have to get the Miller tool #MLR-MD-998767 ($17.47+S&H) to adjust the tensioner pulley (with 2.6 ft-lbs torque – ya right). Instead use a 90 degree pliers in the 2 tensioner pulley holes to adjust it (you may have to cut off one of the handles to clear the compressor pulley and grind the tips a little). Or you can put an allen wrench in one of the tensioner pulley holes and use the tensioner pulley bolt with your socket as a pivot point. The other Miller tool #MLR-MD-998738 (the threaded rod for $8.55+S&H at 800-533-0492) to compress the auto tensioner, I recommend getting if you are going to do more than one TB. Otherwise you can use the VFAQ battery hold down rod idea instead (or even just the 90 degree pliers if you're strong enough, have patience, and a partner). You'll need the threaded rod to compress the auto tensioner to put the holding pin in (and remove) – otherwise you'll have to remove the auto tensioner and compress it in a vise to put the holding pin in.

Replace the "B" belt also at this time. And if you haven't replaced the water pump in the last 40k miles (or you suspect a problem with it), now is the time since you must remove the TB to do it (also get a new water pump gasket and replace the o-ring in the crossover inlet pipe by putting it on the pipe end first, coating with coolant, and then insert pipe with o-ring into water pump – do not put the o-ring into water pump first as it will not seat properly and will leak). I recommend a dealer water pump as they always out last any after market ones (worth the extra $). Replacing the tensioner and idler pulleys at this time is also a good idea if they haven't been in the last 50k or they make noise when you spin them.

 

[steve]

If you compressed the auto tensioner hard enough to break the tensioner arm it's likely toast too.

Where the tool fitting holes in the tensioner pulley go depends on which engine and the final pre-loaded tension on the belt. On 1gs the tool fittings are on top of the bolt and tensioning the pully rotates them clockwise and 2gs the holes are below and you rotate them counterclockwise into the belt.

With the tensioner pulley loose there is more than enough slack on the timing belt with the autotensioner compressed and the retaining pin installed to work on the timing belt.

Steve

 

[j_eclipse96]

Alright thanks guys. I'll order a new tensioner arm and auto tensioner tonight.

So when I release the auto tensioner, the two holes on the tensioner pulley should be facing down, with the bolt above them. Then I rotate the crankshaft once until the timing marks line up again. After that, I should loosen the tensioner pulley and turn it slightly counter-clockwise to put a slight tension on the belt. Correct?

Thanks again guys.

 

[steve]

So when I release the auto tensioner, the two holes on the tensioner pulley should be facing down, with the bolt above them. Then I rotate the crankshaft once until the timing marks line up again. After that, I should loosen the tensioner pulley and turn it slightly counter-clockwise to put a slight tension on the belt. Correct?

No, you should leave the pin in the autotensioner until your almost done.

You can preload the timing belt with the pin installed, turning the tensioner pulley into the belt until the pin becomes loose and slides freely then you lock (torque) the pulley bolt, make sure the pin is still free, and if it is, go and turn the crank over 6 rotations (to line all the timing marks up again) wait 15 mins before checking the pin again.
If it's still free, then you can remove it and check the gap if you like. Make sure you have removed or backed off the threaded rod adjuster before starting to preload the belt so that it isn't holding the tensioner arm.

Steve

 

[j_eclipse96]

Okay thanks alot guys, you just made that last bit 100x clearer. I just ordered a new tensioner arm and auto tensioner from Rockville, should be here sometime next week (arms were out of stock, because who breaks them? ) Gonna be hard to wait that long, can't wait to drive her! Thanks again guys.

 

[j_eclipse96]

Okay, the new tensioner arm got here, but it doesn't appear to be the right one. The arm only contacts the tensioner pushrod about halfway across, and the arm appears to be different when put over the old one. Also the pulley rubs on the tensioner arm then it rotates, which wasn't a problem with the old one. The part number they sent me was MD130032.. They are closed today but I am going to call them up on monday and see what went wrong. Any other suggestions on why it wouldn't fit right?

 

[lookin4dsm]

Okay, the new tensioner arm got here, but it doesn't appear to be the right one. The arm only contacts the tensioner pushrod about halfway across, and the arm appears to be different when put over the old one. Also the pulley rubs on the tensioner arm then it rotates, which wasn't a problem with the old one. The part number they sent me was MD130032.. They are closed today but I am going to call them up on monday and see what went wrong. Any other suggestions on why it wouldn't fit right?

According to CAPS, the "timing belt tensioner arm" part number for a 1998 GSX is
MN119896.

Mike

 

[j_eclipse96]

I went by the above post in this thread that said it was PN MD130032, and thats what I ordered from Rockville. Maybe that is a 1g arm instead of a 2g one? Regardless, I should have looked into it further instead of just ordering it according to a part # posted on here.

To prevent future problems, can I get one of those CAPS cds on ebay, and how do I know if it has the CAPS function or not?

I guess I'll call up Rockville when I get home tonight and figure stuff out, and order MN119896 and send back the one I have. Hopefully this new one is the correct one, and she'll be back on the road sometime this week. Then I can enjoy until something else breaks Thanks again guys, I'll update again soon.

 

[lookin4dsm]

To prevent future problems, can I get one of those CAPS cds on ebay, and how do I know if it has the CAPS function or not?

Download CAPS here:

http://www.stealth316.com/2-wincaps.htm

Mike