325i Sport Gearbox reconditioned?

[BIGJO]

Hello there, got a bit of a problem at the moment. Just rebuilt my engine with a high lift Shrick cam (288) & high performance valve springs. However, the gearbox cannot take the power due to it doing 183k by previous owners & myself.

The gearbox is making noises when i release my foot of the clutch. I have taken it to a BMW specialist who has advised me to either get the gearbox reconditioned or to pay £200 for a second hand one that he has (Sport gearbox).

Not to sure about a second hand one as the majority of E30's these days have at least 100k on the gearbox. Also, how can i ensure that after a couple of years the second hand gearbox won't need replacing or fixed as well?

Think getting a reconditioned gearbox is the only real option, however i do not know where i might be able to send my gearbox off to for it done.

Just wondering if anyone can help me?

Many thanks, Jo.

[Dr Firefly]

I asked the same recently, but I don't think it's that commonly done as the used ones are pretty cheap these days and it's easier to just change them for another as they wear out. I'm sure in 5 or 10 years a lot more people will be doing it. Have you asked the BMW specialist who they get to recon their gearboxes and engines? Because they probably won't do it in house, they'll send them to a specialist.

[BIGJO]

Spoke to the fella working on the car & he said he could rebuild it himself, however because he's busy, he's not able to do it at the moment.

As the engine's been rebuilt i think the best option should be to get the gearbox rebuilt as well. This should improve the car's performance as well & should last for a long time. If i do however do decide to pick up a second hand gearbox, it may just last a year or so as the engine is pumping a lot of power.

Really not sure what to do to be honest........

Jo.

[Turbo-Brown]

Think you might struggle to properly bust one of the gearboxes.

They seem to handle pretty beefy power and, more importantly, torque outputs.

I had a quote for about £500 odd last year for a recon I seem to recall though, have a search on the internet, seems there are lots of places offering the service.

Dunno if the internal bits would be available from BMW though, gearboxes aren't really all the complex inside, you just need to be extremely methodical when taking them apart and be ready to catch all the little ball bearings and springs which fly out at you.

Great fun!

[Martinaston]

All the bearings are still available from BMW and not that expensive, but i'm not too sure about the shims.
The individual gears are a fortune though

[Chris-W]

Is it making nasty noises under load, or is it just at tickover that you notice the noise when the clutch pedal is released?

[BIGJO]

When the car is in neutral & the clutch is lifted up......it makes a rattling noise, the car starts shaking (minor though). Just wondering what it is as i'd rather get it sorted asap!

Spoke to a chap on the phone from a gearbox place on the phone, he advised me to pop up so he can see what's wrong with the gearbox. He said that it could be the clutch that needs replacing, but the clutch is fine.

Think i need it all looked at before something goes wrong.

Many thanks, Jo

[Chris-W]

Might just be your clutch release bearing.

[BIGJO]

Hopefully mate! I really hope it's nothing major as i've spent most of my money rebuilding the engine & putting a few extras. Not got a lot left for all this Black & Decker business.



Many thanks to all, Jo.

[ian332isport]

If it only rattles at tickover with your foot off the clutch, then it's a 'feature' of Getrag gearboxes. My original 5 speed did it and my current 6 speed does it. It's very common and not actually a problem.

It's basically the gears chattering against each other when they are not under any load. Lumpy cams make the noise worse due to a slightly less smooth tickover. It's not the release bearing as this only spins when you press the clutch, not when you release it.

If you do find it's a problem then I can HIGHLY recommend these guys for a rebuild.

http://www.hardyengineering.co.uk/

Cheers,

Ian.

[BIGJO]

Is there no cure for it though?

It only occurs when i release my foot of the clutch. I can't really hear it that much as the car sounds like a drag car since it's had the cam in it alongside the engine rebuild.

Thanks, Jo.

[ian332isport]

Is there no cure for it though?

It only occurs when i release my foot of the clutch. I can't really hear it that much as the car sounds like a drag car since it's had the cam in it alongside the engine rebuild.

Thanks, Jo.

No cure that I'm aware of

It was also something that afflicted some Vauxhall Carltons (also used Getrag gearboxes). Way back when Carltons were current, I believe that Vauxhall supplied a special synthetic oil that quieten'd it down, but this has not been available for quite some time.

You could maybe mess around with different oils, but if you go thicker to make it quieter, you also increase drag and therefore reduce power to the wheels. A good quality synthetic oil of the correct (standard) viscosity may be an improvement, but don't hold your breath.

Sleep well in the fact that it's not about to fail on you. The box is actually very strong and is extremely unlikely to die. It's more of a charactristic than a fault

Ian.

[Chris-W]

It's not the release bearing as this only spins when you press the clutch, not when you release it.

Quite right - apologies.

[BIGJO]

Someone did mention Vauxhall Carltons when i enquired about the noise. I don't understand why the box didn't make any noises before the rebuild & cam?

Maybe because the car was away for like a month for the work, now that i got it back it's more powerfull i tend to put my foot down more often. That's probably the cause

Thanks, Jo.

[ian332isport]

I don't understand why the box didn't make any noises before the rebuild & cam?

It's because the tickover is not as smooth. This causes the gears to rattle more. If you went back to a standard cam it would probably go away (or at least get quieter).

You should hear my 6 speed. Sounds like a bag of spanners at tickover

Ian.

[Turbo-Brown]

It's not the release bearing as this only spins when you press the clutch, not when you release it.

Not sure that's true Ian, the spring in the slave cylinder keeps the bearing pressed against the clutch all the time so as long as the engine's running, the bearing will be spinning, just not under any great load.

[Chris-W]

Excuse my back-and-forwardness, but a dying release bearing will be audible at tickover with the clutch pedal released. Sound goes away when the pedal is depressed & the bearng loaded up.

There.

Sorry - been under a car all day in 25 degree heat.