Isuzu MU repair workshop

[johnsydney]

Hi there. I'm a newbie to isuzu and would like to find out where do people go for repairs on Isuzu MU in Sydney?
I recently have a problem with the harmonic pulley. It wobbles and does not seem neatly fit onto the crankshaft.
The mechanic tells me the only way to fix it, is to replace the whole engine. Please help. Desperado.

[geeves]

If its what I think he has a very slight chance of being correct. Lets hope not.
The real problem is that at some stage the large crank nut was undone when doing a timing belt change and its almost impossible to tighten correctly with the engine in place. When it loosens it moves a spacer behind the pulley which has a keyway in it and keys into the crank. The keyway weres and can damage the crank although this is uncommon.
To fix you need to take off the pulley and inspect the spacer and repair and replace as necessary.

[frederick]

Hi,I agree with Geeves, I also had the same problem with my Big Horn. My crankshaft pulley started wobbling and the belt would fly off. Took off the pulley and the bolt had lost its thread. One of the dismantlers here in Auckland told me that its common with the 3.1 engine. The key way of the pulley was damaged. Got a pulley from Isuzu bits and put thread lock on the new bolt and its good as new now.

[johnsydney]

Thanks guys for the explanation on the pulley. And true enough, the keyway is alittle worn but more so is the inner part of the pulley. Does anyone know where I can buy the harmonic pulley part from Sydney or order from interstate?

[geeves]

My 2.8 did this 70000km after a belt change. Dont know if the bolt striped as we never found it

[Fly3r]

Tom's One Stop Auto Shop, looked after mine when I was in sydney. He also did the timing belt change . let me know if u want more detail...
good luck with it

[geeves]

Could be a harder part to get in Aus as it only applies to the belt drive engine which holden didnt use. For what it is its expensive too.

[johnsydney]

Hey guys, Really appreciate the advice. At the mo, the mechanic that is working on my car has made a mess and taken out the crankshaft and other partts out of the engine. And no other mech wants to touch it because it's already apart. So, the only way for me right now is to get a harmonic pulley and instruc the mech to fix it as per suggested by frederick. Now the issue is , where can I find the part.

[geeves]

Try your friendly holden dealer first but if not www.4x4isuzu.com might be able to send a good one from NZ. Be sitting down while asking the price even second hand.
As the crank is out you might as well measure it up and fit a new set of bearings. If the end of the crank measures as undamaged you might be able to get out of paying a large portion of the bill

[Bargie]

Hi mate i had the pulley retaining bolts let go on my 2.8 td and it flogged the pulley out but the boss that goes on the crank is still ok. as i got a complete unit s/hand with weeks of searching i put the whole unit on.
so i have the boss for the crank sitting in my shed if you want to buy it.
my s/hand pulley/boss assy cost me $300.00 just to let you know what they can cost.

Pm me if you are interested.
cheers Glen.

P.S. i will be away for the w/end so wont reply till next week.

[geeves]

I can send you a copy of the 2.8 engine repair manual. PM me with an email address.
Its 8 meg in size

[pig75]

Give these guys a call http://www.precisionparts.com.au

[mymu1993]

Same problem with mine, pulled out pulley but boss is still wobbly.

Had a quote from www.precisionparts.com.au $154+ GST for Holden Rodeo 2.8 harmonic balancer , but it doesn,t look the same.

Any advice on what is next? is thread normal on that mf bolt?, is air impact wrench suitable tool for that? i guess timing belt has come out?

Thanks in advance.

[geeves]

It probably is different. I dont know why but Australia never used the belt drive 4jb1 engine.

[pig75]

try a 3.1 jackaroo

[pig75]

i am 99% sure the 3.1 is the same size as the 2.8 try holden for a new part.
You might need a chair
belt drive

belt drive.jpg

gear drive

gear drive.jpg

[mymu1993]

Yeap, top one looks just right,
is #20 sprocket sits on crankshaft tied? or is it pushed against something? still puzzled how and what could give so much to make it so wobbly,

[pig75]

It’s all keyed then the bolt clamps it against a shoulder on the crank

[geeves]

Human error
When the cam belt was last done they undidid the large center bolt instead of the 4 small bolts. This torques to about 150 ft pound which is nearly impossible in situ. So over time it comes loose and you have movment which wears things out. Mine took 70000km for the bolt to fall out

[Bargie]

I found that when i had to change my balancer and mounting boss i used a big breaker bar and just give the engine a quick crank and that undid it easy and when doing up with tension wrench i put the MU in 4wd low and 5th gear and that locked the engine from turning.
i also put some loctite on the bolt so it wont come loose again.
and when refitting balancer i used new bolts of a 8.8 grade and they are allenkey headed bolts.
as the originals stretched when i first did the timing belt as that caused the bolt failure.
has been done for 5000km and not moved at all.
hope this helps guys.
cheers Glen.