E30 gearbox to change or rebuilt

[johnathan540]

I just had my 318 M40 manual gearbox removed due to faulty bearings. Would appreciate any advice on whether I should change to a used gearbox from the chop shops or rebuilt it by changing all the bearings. How much does these gearboxes cost and I heard they are quite hard to come by. Its was really quiet until i change the clutch, housing and bearing. How could something as simple as changing a clutch set screw up the gearbox!tHANKS.

 

[leforte]

are you using the correct clutch, housing and bearing for your gearbox? if you are suffering from chattering-like sound on idle or while engaging your gears, chances are you may have installed a wrong clutch kit.

your car should be having a single mass flywheel, and a spring loaded clutch plate is required as a dampener for any drivetrain vibrations. Should you have installed a solid plate clutch, with no spring in place, the vibrations can be heard as noisy and chattering-like sound from the gearbox.

both type of clutch plate, be it the spring loaded single mass designated OR the solid plate duo mass designated flywheel will fit into your car, its just a matter of fitting the correct one.

don't think there's anything wrong with your gearbox as the getrag unit is almost a bomb proof design with over engineered parts. regular gear oil changes will keep it going for almost the entire lifetime of the car.

 

[chriseunos]

im having the same problem, i think it's due to clutch bearing...or maybe the pressure plate. i stand corrected

 

[johnathan540]

Leforte, I bought the cheapest clutch set-up, LUK for RM400. It was said to be for the M40 by the spare-part shop. Its the quality I'm worried about... shouldn't have been penny wise, pound foolish. I just thought it would be the same usage.

It started with some grinding sound every time i release the clutch and when I decelerate.... like two plates scheming each other. Then after a week, i heard the gearbox cluttering below..going clack, clack, clack.

My mechanic told me that the bearings are damaged. When I turn the shaft's that protruding from front of the gearbox, its very rough and I could even hear sounds of small little ball bearings knocking each other.

Anyone got a gearbox removed from a previous conversion?

Thanks

 

[leforte]

hey john,
even with the wrong clutch plate, you will still not damage your gearbox as the clutch is merely a coupling for the transfer of engine power to the gears. furthermore, the clutch assembly and your gears are house in a different compartment and its impossible for them to even mess up each other. ANyway, did your mech use the centrerizing pin to aligned the clutch, pressure plate and release bearing with the input shaft, most malaysian mech dont, "thinking they are smarter"? anyway, if its installed off centred it will be noisy as well even if you use the right clutch which is the spring loaded one. and should you have change your manual gearbox oil while replacing your clutch, IF a wrong weight of oil is use, your gearbox will also be slightly noisy but it will be a constant hum and not only while you de-clutch.

anyway from your description, with the noise only appearing when you de-clutch, its the exact symptom of installing a solid non-spring loaded clutch with a single mass flywheel. check the pictures i attached below, i am betting that you install the one without the springs? IF your mech tells you he doesnt know the technical difference in them, he should not be touching your car. IF he tells you the bearing in the gearbox is gone and the ONLY remedy is to replace the gearbox, its time to get a new mech. there's few bearings in the gearbox and they hardly fail anyway. if any of the planetary gears in your gearbox should fail, you can always check your gearbox oil for metal bits and particles.

please refer to the pictures attached. which clutch plate did you install?

 

[johnathan540]

e30 M40 manual gearbox rebuilt

hey john,
even with the wrong clutch plate, you will still not damage your gearbox as the clutch is merely a coupling for the transfer of engine power to the gears. furthermore, the clutch assembly and your gears are house in a different compartment and its impossible for them to even mess up each other. ANyway, did your mech use the centrerizing pin to aligned the clutch, pressure plate and release bearing with the input shaft, most malaysian mech dont, "thinking they are smarter"? anyway, if its installed off centred it will be noisy as well even if you use the right clutch which is the spring loaded one. and should you have change your manual gearbox oil while replacing your clutch, IF a wrong weight of oil is use, your gearbox will also be slightly noisy but it will be a constant hum and not only while you de-clutch.

anyway from your description, with the noise only appearing when you de-clutch, its the exact symptom of installing a solid non-spring loaded clutch with a single mass flywheel. check the pictures i attached below, i am betting that you install the one without the springs? IF your mech tells you he doesnt know the technical difference in them, he should not be touching your car. IF he tells you the bearing in the gearbox is gone and the ONLY remedy is to replace the gearbox, its time to get a new mech. there's few bearings in the gearbox and they hardly fail anyway. if any of the planetary gears in your gearbox should fail, you can always check your gearbox oil for metal bits and particles.

please refer to the pictures attached. which clutch plate did you install?

Thanks for the detailed explaination. That's exactly what my usual mech said about what happened. You see, he was really busy during that time and instead of waiting I sent my car to someone else (thinking that its a simple installation). My mech also mentioned that a lot of foremans usually would sucumb to using a hammer to force the gearbox in when its not aligned properly. Therefore, to other M40 owners make sure your mech knows what he's doing before leaving your car to 'one of their boys' with this so-called easy installation without the right supervision.

Anyway, I decided to rebuilt the gearbox instead of sourcing for used ones as the only available units would probably be from local models which have been taken out due to conversions and therefore quite aged. The chopshops only have auto boxes from Japanese spec models. The gearbox was taken apart and the found that the front gearbox bearing was completely crack and split, with ball bearings all over the place. Must have been some serious shuffing it endured. Since the box was apart, I decided to change what ever wear & tear parts possible even when its not completely damaged. I listed the item & part no for anyone who's interested to take this route:

1) gear box bearing (Fag) 23121224375
2) rear groove ball bearing 23121228292
3) roller bearing 23121282566
4) roller bearing 23121224375 (this is same bearing as the above (3) except for the cover which has a slot in the middle. Its usually not available but bearing (3) could be used by using the old cover.)
5) shaft oil seal (m) 23121205430-0
6) shaft oil seal 23121282394
7) shaft oil seal 23111228314

and then there's labour which is not too expensive. I'm not sure whether I should be listing prices here. Don't want to piss off anyone who's actually running this sort of business.

 

[jeembo]

johnathan...i think you should list the prices lar...so dat we can compare. i think no harm would be done cos sometimes we are being charged over price man...thanks!

 

[leforte]

Ouch!!! i feel your pain in the pocket. just in case if you feel like needing a NEW gearbox, you may checkout bavarian auto in segambut, heard they have one in stock, totally new.

 

[laneza]

aiseh sounds pitty becouse of RM400 cheap clutch..u have to pay extra thousand of $$$...

 

[johnathan540]

aiseh sounds pitty becouse of RM400 cheap clutch..u have to pay extra thousand of $$$...

If you check out leforte's posting earlier, its not due to the clutch that damaged the gearbox but the person that installed it. This has been confirmed by the gearbox specialist when it was opened. The front bearing was completely wreck because the inexperience mech forced the gearbox in, probably with a hammer or something. Apparently, there's some sort of measuring equipment that's required to get it aligned properly before slotting the gearbox shaft into the clutch and flywheel assembly. SO ALL E30 DRIVERS MAKE SURE YOU SENT YOUR CAR TO SOMEONE WHO KNOWS HOW TO GET IT DONE PROPERLY. Its not as simple as you think.

 

[pussy]

sorry, john, i just reached home, got your PM..

hmmn.. seams you proceeded on doing back the box.

ps. yes, the half car is still available. theres a right one also comming over next month.

regards.

 

[leforte]

If you check out leforte's posting earlier, its not due to the clutch that damaged the gearbox but the person that installed it. This has been confirmed by the gearbox specialist when it was opened. The front bearing was completely wreck because the inexperience mech forced the gearbox in, probably with a hammer or something. Apparently, there's some sort of measuring equipment that's required to get it aligned properly before slotting the gearbox shaft into the clutch and flywheel assembly. SO ALL E30 DRIVERS MAKE SURE YOU SENT YOUR CAR TO SOMEONE WHO KNOWS HOW TO GET IT DONE PROPERLY. Its not as simple as you think.

THAT's the problem with all our local "smart" mechanic including the few specialist bmw workshop recommended. they all claim to KNOW but do they follow the actual technical procedure and utilizing the proper tools to do the job???? NO... most of them will just go on with their habitual way of doing things, using the wrong procedure ie, those meant for other makes and improper tools. so IF you are lucky, you will be off with a working car but chances are you will not be so lucky, and the aftermath would be a constant return visit to your dear friend for remedies... which in most case, the root of the problem would have already spread like a cancer to other working parts.

a reputable mech is essential but as a supplement i would advise everyone to do a proper research on the internet, for all the proper procedure for the replacement of the particular part before actually venturing to your fellow mech. watch them as they do the work and rest assured, should there be a error in the process you will be there to spot it before it actually causes more damage later...

 

[fabianyee]

hmmm.. mine oso have chattering on neutral but goes away when I depressed the clutch pedal or when I applied slight force to push the shifter into gear. So I deduced the free play is from within the gearbox. Didn't give me any problems after so long so I left it as it is for now...

 

[Bmmad318i]

hmmm.. mine oso have chattering on neutral but goes away when I depressed the clutch pedal or when I applied slight force to push the shifter into gear. So I deduced the free play is from within the gearbox. Didn't give me any problems after so long so I left it as it is for now...

Same experience here....other then that it works fine.

 

[elwine30]

mine also behaves the same. unless someone try to change the bearing inside.

 

[pussy]

it's common on the single mass fly wheel..usually the trust bearing worm gear worns out or the distance contact point has a free play.. so it's flywheel chatter..

even a dogleg box is worse..somemore with lighten flywheel..

elwine, yours chatter cos you removed some weight..

 

[elwine30]

so, will it make any difference if i change the bearing?

 

[pussy]

nope, change the flywheel..

 

[Zoggee]

even a dogleg box is worse..somemore with lighten flywheel..

dude...my dog got no sound at all. and not even intsalled by a bmw specialist sumore.

I'm back on my old trusty 240 getrag. Still running fine. No sound from the gearbox at all.

Now my rear diff is howling....very loud.

 

[pussy]

you very lucky your dog never whine.. hehehhe

but i notice that the single mass wheels has more problems than the dual mass..