[limuman]

Hi guys, My car developed a rattling noise from the crank case recently. Initially it was barely noticeable and then it slowly became louder especially at high revs. i just had it examined by my mechanic.
He says the noise is coming from the right hand balance shaft. He says the balancing shaft bush is worn out or damaged.
According to him, the balance shaft can be disabled by removing the gear that meshes with the oil pump gear and replacing it with a spacer which will not be in contact with the oil pump gear. He says this should solve the problem. he however has warned that i might experience some higher vibration of the motor especially at low revs.
The alternative is to replace the bush. According to the engine manual, replacing the bush appears to be a major operation that requires special tools and basically removing the engine from the car.
Has anybody ever done this? I mean disabling the balance shaft. By the way, disabling the shafts will cost a lot less (for now at least)if nothing else gets broken as a result of the higher vibrations.
Any advise will be welcome.

[trekker1]

Not an uncommon practice on the 2.5 range, as disabling is only a matter of removing or simply not replacing a broken balance shaft belt.

I maintained such a Paj, and have to say I didn't feel any additional vibrations. This particular engine leaked oil from the front seals after I fitted a new balance shaft belt, so I returned it to as was, and my friend was quite happy for years after.

An engine rebuilder advised me he avoided fitting new bushes due to subsequent problems of premature bush failure, and plugged the bush housings instead.

[Marty Russell]

I have owned a 1989 Gen1 Pajero LWB station wagon since 1999. It has a 4D56 2.5 litre turbo diesel motor. On two occasions over the years I have had the balancer shaft belt come off the drive pulleys and jam in the timing belt. In the first incident I was able to repair the head, but on the second occasion I was driving at 110kph and the camshaft bearing caps tore out from the cylinder head. Apart from bent valves and a wrecked head there was no other damage to the rest of the motor.

Having read messages relating to similar incidents on the UK Pajero Club website, where there are many owners of Gen1 Pajeros, I decided to run the motor without balancer shafts. There is a little more vibration, but as I removed them three or four years ago neither my wife nor I notice it. It is of interest that the fuel consumption improved slightly to 12.5 litres per 100km.

I would not hesitate to remove the balancer shaft belt on your Pajero. After all, if you find the additional vibration unacceptable, you can always put the belt back again!

it is a pleasure to be able to make some useful comment on the SA Pajero Club website because few people now own Gen1 Pajeros in South Africa as only a few were imported or came in as 'grey imports'. Elsewhere in Africa - Kenya for instance - they are a common sight on the roads.

Our Pajero has now done 350,000 kms, 200,000 of those kms have been done by my wife and myself - mostly on safari. We have driven and camped in all of the African countries from South Africa to Kenya with the exception of Angola.

The Gen1 is a tough wagon. All steel bumpers, no external plastics, the same chassis and gearbox as the early Colts, the same motor as the current Hyundai one tonne bakkies - so no problem with spares, NO electronics (I have even replaced the electronic glow plug timer with a manual switch on the dashboard, comfortable, a/c, power steering. My wife loves it!

Best of all, I can fix anything that goes wrong myself, no one wants to steal it and insurance is cheap!

[limuman]

Matty and Trekker1,
thanks guys for your comments. i have actually decided to go ahead and disable the balance shaft. My paj is still on the operating table (and am the surgeon ). still working on figuring out how to plug the bush housing so as not to loose oil pressure when the motor is running.
will come back and post on how it all goes.
Big ups guys.

[trekker1]

Hi again limuman.

I don't think Marty plugged the bushes as you are considering, certainly I didn't, and nor will any of those who simply leave the timing belt off.

The plugging I referred to was at a machine shop, on engines being re-bored and made ready for a total re-build by an agent.

[paramaniac]

I have a 1985 gen 1 Pajero with the 2.5D motor, the balancing shafts have been disabled with no ill-effect, motor is smooth, can't vouch for the improvement in fuel consumption as the motor has just been totally overhauled. I am, however, contemplating going the lexus v8 route sometime in the future. I have the high roof wagon version and the motor just doesn't like that big body.

[Marty Russell]

Trekker1 is correct. I left the shafts in place after removing the drive belt - just leave them where they are and they will keep the holes blocked! You could even remove the belt without disturbing the timing belt. Just take to top timing belt cover off, cut the balancer shaft belt with a pair of snips and withdraw the cut belt. A fifteen minute job!