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View Full Version : Urgent problem with Mitsu. van crank pulley.



coldamus
27-12-2007, 06:24 PM
I apologise for this long post not being about a Magna. It is about a fat relative though, the Mitsubishi WA Van.

Firstly, does anyone know the Mitsubishi engine type for the 2.4L petrol engine in the 1998 WA Van. Not the traditional L300 Express van but the walk-through version with a sloping front that looks like a Delica. It is definitely not the same engine as the L300 in the late 80's and early 90's. I'm hoping it may be the same as 4 cylinder Magna 3rd Gens. If so, their workshop manual may help. Gregorys/Haynes do not make a workshop manual for the WA Van.

Secondly, can anyone shed some light on the following problem because it does not make sense to us.

The van belongs to my brother. He is in Brisbane and I'm in Sydney so I haven't seen the situation first hand.

The cam belt was recently replaced but the workshop that replaced it is closed for the holidays. After it was done, the car was Ok for a while but in the last few days has been down on power and the engine vibrating badly. It turned out that the crankshaft pulley, which apparently includes a dynamic balancer, was wobbling badly.

My brother tried to take it off. First problem, it was very tight and he broke the central bolt that he thought held it on the crankshaft.

Second problem, the pulley still wouldn't come off. Apparently it was held on by four bolts spaced around it that screw into the cam belt drive cog. It now seems that the central bolt actually holds the cam belt drive cog onto the crankshaft and the pulley is bolted to the cog.

Third problem, after undoing the four bolts and getting the pulley off, the cam belt drive cog slid forward slightly. Its front surface is recessed, so he can't get at the broken bolt stub to get that out.

OK, he has bought a new bolt, so if he can get the old one out, it should be just a matter of putting the new one in and tightening everything up.

It is pounds to peanuts that it was stuffed up when the cam belt was replaced, but what could they have done wrong?

The bolts were all very tight. The cam belt drive cog is splined onto the crankshaft, so you wouldn't expect much play there. Yet from my brother's description, the pulley was acting as loose as Britney's morals. Well, maybe not loose but wobbly.

Since the cam belt is involved, we want to ensure the whole assembly is on properly this time. Also, being down on power might indicate the valve timing was affected. A cam belt that loose doesn't bear thinking about.

Any clues would be most welcome.

No name
27-12-2007, 06:59 PM
I'm pretty sure that they have the 4G64 engine. Same family as the L300 4G63 (2.0L) just bigger.

I'm very surprised that you managed to brake the bolt going into the crank! If they had the timing a tooth out you would of felt it straight away when you got the car. These engines have 2 belts. I'm thinking it may have something to do with the balance shaft belt because you said it vibrated badly.

Other than that it wasn't just a normal misfire?

Madmagna
27-12-2007, 08:07 PM
If it is the same motor I am thinking of, it is a close relative of the 2.4 in the TE, there are slight variences.

The problem may be an incorrectly tensioned balance shaft belt, this may be ok for a time but the the belt slips and all goes wrong.

This however is unlikely given that the front pully was all over the place. From memory these have a rubber sleve to dampen them, this can come loose with age and cause a similar thing.

To break the bolt when taking it off is strange even if it was over tightened. The bolt is nto all that hard, you should be able to drill it and then use a large easy out to get it out. The only issue here is that he may have used a ton of lock tight on it and even an easy out will not then get it out.

coldamus
27-12-2007, 09:29 PM
Thanks for the advice. I had forgotten about the balance shaft belt. That will need looking into. Hopefully we will know more tomorrow.

magna buff
28-12-2007, 02:16 AM
usually the timing pully is on a keyway as well


the motor may need the crank replaced
this would be cheaper than having the broken bolt machined out and rethreaded etc

the problem happend on a few pajeros years back

thought it was solved

might be bad workmanship /cross threading