94 3.2L How to adjust timing belt tension?

[nujac]

I recently changed the timing belt on my 94 3.2L trooper but feel that the belt jumps around to much when running. Does the tension pusher always create tension on the timing belt or only when the adjustment idler pulley is loosened. I was told on some cars you have to loosen the adjustment idler pulley bracket so that the pusher can tighten up the belt. Is this the case on my trooper.

[atfdmike]

The timing belt tensioner is the same for both the SOHC and DOHC engines. It applies pressure to the bellcrank which keeps the tensioner pulley tight against the timing belt. It is adjustable to a degree. Very often, the tensioner must be cleaned or replaced when performing the belt change. It is not a cheap item, but I understand that it does wear out. Also, many people recommend changing the water pump when doing the timing belt, as they are all accessible and since so much work has to be done just for the belt, many just go ahead and do the tensioner and water pump at the same time. The manual says the tensioner rod protrusion should be from .16 to .24 of an inch.
Good Luck, hope this helps.

1994 Isuzu Truck Trooper (4 Door) V6-3165cc 3.2L SOHC (6VD1)

Vehicle Level Engine, Cooling and Exhaust Engine Timing Belt Tensioner Specifications Torque Specifications Torque SpecificationsTensioner Adjusting Bolt 31 ft.lbTension Pusher Bolts 14 ft.lb
NOTE: When reusing the pusher, press the pusher to retract the rod (1.4 mm piano wire).

1. Remove double clips from pulleys. Temporarily install the crankshaft pulley. Turn the crankshaft pulley clockwise by two turn and make sure that the rod protrusion is within the standard.

Standard: 4 - 6 mm (0.16 - 0.24 in)

1. If out of standard, remove pusher, loosen adjusting bolt, and readjust. Repeat from step 11. Tighten adjusting bolt to the specified torque.

Torque: 42 Nm (31 ft lbs)

1. Pusher

• • Tighten bolts to the specified torque.

Torque: 19 Nm (14 ft lbs)

[nujac]

Where is the adjustment screw? It appears that the idle roller is always free to move up and down with the pusher. Should the idle roller by the pusher be free to move?
thanks for your time
Carroll

[atfdmike]

I am not sure if I understand what you are asking.....did you reinstall the pusher and find that it was out of tolerance, ie: less than .16 or more than .24 in. of the rod showing when it was in place? The pusher appears to have two bolts which may allow some adjustment, but the only written directions I have are what I previously posted. Maybe someone who has had to adjust theirs can give more info., but the Trooper forums are not as active as they used to be due to the loss of owners and dealers, so it could be a while before you get more answers. Can you examine the pusher and see an adjustment on the bottom of it? If not, then what about the belt pulley: does it have an eccentric on it somewhere that can be changed? Just some ideas to get you started. Good luck.

[trooperbc]

Originally Posted by nujac

I recently changed the timing belt on my 94 3.2L trooper but feel that the belt jumps around to much when running. Does the tension pusher always create tension on the timing belt or only when the adjustment idler pulley is loosened. I was told on some cars you have to loosen the adjustment idler pulley bracket so that the pusher can tighten up the belt. Is this the case on my trooper.

Originally Posted by nujac

Where is the adjustment screw? It appears that the idle roller is always free to move up and down with the pusher. Should the idle roller by the pusher be free to move?
thanks for your time
Carroll

• did you install a new tensioner when you installed the new timing belt? it is always recommended that you do.
• is the tensioner functioning correctly, i.e. is it producing the 200lbs or so of pressure. if you reused the one installed, did you check it? you should not be able to push that rod in by hand; if you can, than it needs to be replaced. you should not be able to install the timing belt with the push rod out; it would need to be pushed in with a vice and a wire inserted in the hole to hold it in until the timing belt is installed.
• yes, the tension pusher always creates tension on the timing belt by pushing against the belt tensioner (the pulley looking piece with the 'paddle' that the tensioner pusher pushes on
• as shown in the illustration in the post with the alldata info, when everything is installed (timing belt and tensioner, etc) with the pusher pushing against the belt tensioner pulley and the belt tensioner pulley pushing against the belt, that protruding rod of the pusher should measure between 0.16" - 0.24" (you can measure this with a mic or with a combination of feeling gauges.)
• if the tensioner pusher is new, or the old one is still operating correctly, you can make minor adjustments (though you usually shouldn't have to if everything is working ok). anyway -- the adjustment bolt is in the middle of the belt tensioner. the factory manual says: """ If out of standard [the pushrod protrusion measurement], remove pusher, loosen adjujsting bolt [on belt tensioner pulley] and readjust. [then] tighten adjusting bolt to the specified torque [31 ft-lbs].""" i personally don't see the need to remove the pusher because it requires you to repeat a bunch of steps that don't seem to need repeating (including pushing in that pusher and installing the wire pin to hold it there until all is installed), but i haven't had to do that adjustment, so maybe someone who has will chime in about this.
• yes the belt tensioner pulley moves with the pusher, because that is how the belt is tensioned. but when all is installed there shouldn't be any play going on that you can induce by hand -- all this is at that 200 lbs of force produced by the pusher. the way you write about it, i'm thinking your tension pusher is shot.

did i miss anything?

hth

//bc

[nujac]

I install a new pusher, two new belt rollers, and the roller bracket. Looking at my old parts I do not see how the bolt that holds the pulley on can be adjusted. All of the pictures that I have seen of this bolt looks line it is off centered and can be turned for more tension. My bolt is dead centered.

I did have a notice that came with the PCI TS26220 kit is said.

"Notice"-T60381
The enclosed Tension Adjuster is a new design.
It may appear shorter in length than original.
This is the new OEM design. It will operate
correctly when installed correctly and according
to the vehicle manufacturer instructions.
Bulletin T60381

[2eyefishclaw]

There Is No Adjustment The Tensioner Is Hydraulic And Will Automatically Take Care Of Slack Unless You Have The Wrong Tensioner Or Its Just A Bad One

[trooperbc]

Originally Posted by nujac

...I did have a notice that came with the PCI TS26220 kit is said.

"Notice"-T60381
The enclosed Tension Adjuster is a new design.
It may appear shorter in length than original.
This is the new OEM design. It will operate
correctly when installed correctly and according
to the vehicle manufacturer instructions.
Bulletin T60381

so -- now we need someone who has that Bulletin T60381 to see if it has a clue as to what your install problem is. or perhaps 2eyefishclaw has access to it, and/or has installed this new design and can clue us in. . .

btw, 2eyefishclaw: my 92 does have the adjustment on the belt tensioner (pulley); i didn't have to use it, but are you saying not to use it? even if the pusher's protrusion is out of spec?

finally, nujac: you did remove the 'grenade' pin from the pusher, right? and now that it is installed, it's tight, or it is easily moves in and out. if it moves in and out easily, sounds like you got a bad one.


//bc

[nujac]

I did remember to remove the pin.

[trooperbc]

Originally Posted by nujac

...Looking at my old parts ...I did have a notice that came with the PCI TS26220 kit is said.

"Notice"-T60381
The enclosed Tension Adjuster is a new design.
It may appear shorter in length than original.
This is the new OEM design. It will operate
correctly when installed correctly and according
to the vehicle manufacturer instructions.
Bulletin T60381

...

OK, i'm a little slow on the uptake, i guess. i googled those numbers you gave and came up with this site
http://www.store.partsdinosaur.com/page129.html
is this where you ordered this stuff? to me this is some cheap priced and cheap looking stuff. personally, i'd only do true oem/dealer parts for this job. there's no way to tell if these parts are good to go or not. did you exactly compare the parts to your old ones before installation? i'd be very wary of these things myself, and wouldn't trust it on a slow boat from china.

i also googled "pci" and came up with the site of the 'manufacturer', here:
http://www.preferredcomponents.com/index.htm
there's an address and telephone numbers. call them and ask obout that "Notice" and "Bulletin T60381".

frankly, i think you'd be better off eating the price of this stuff, chalking it up to educational expenses and buying the good stuff from st. charles isuzu in missouri (free shipping, discount, expertise--ask for merlin) or
jlemond who is a real isuzu expert and sells many oem isuzu parts and is well respected on these and other forums -- check the FAQ for the contacts on both these. here i looked it up.
http://isuzu.stcharlesauto.com/Department-Parts.aspx
call merlin...they are open saturday am.
try searching for "jlemond" on this site and send him an email or PersonalMessage.
i found this post in another thread

This is a perfect question for Jerry Lemond, he would know exactly what to do. jlemond@bellsouth.net

he is an isuzu tech.
__________________
-Ryan
Isuzu Moderator

btw, you usually don't need to replace the pullies and such unless they are bad.

good luck


//bc

[nujac]

Thanks for the advice. I replaced the pulleys because the bearnings were out and the pulleys also had rough surfaces where the belt rides. All the parts that I pulled off looked the same as the new ones. I did install a Goodyear gatorback belt and was going to keep the new one that came with the kit for a spare. I pulled the cover off of the belt after putting about 100 miles on the car. It seems that the belt is tighter now if I check it by hand than when I first installed it.