Cracked Gearbox Housing

[Mister25t]

Hi there,

I have owned my Series II R33 GTST for over a year and it has always had clutch troubles; at first suffering from feeling notchy and grinding the odd shift with the engagement point constantly moving but slowly getting worse with the clutch sometimes slipping when dumped hard and other times peeling the tyres over with little effort required and now when the engine is running it can't select a gear and tries to roll forwards like the clutch is not even disengaging at all. I havn't driven it in months as i havn't had the time to work on it, but this week i got some clutch cylinder rebuild kits to see if that would help (i have have tried bleeding it so many times) but today when i dropped the slave off i see that around the clutch fork hole in the bellhousing is all cracked. The cracks are pretty extensive and go right to the front face of the bellhousing and underneath as well but it seems that they have been caused by the operation of the clutch slave cylinder?

Obviously im going to have to drop the gearbox to weld it up or replace the front housing but does anyone have any insight into the cause of this problem? The car supposedly has a brass puck clutch and the clutch pedal is quite heavy so could a heavy and perhaps failing clutch cause this sort of issue?

Cheers for any input, just seems strange i've never heard of anything like it and couldn't find any reference on the forums either.

Edited March 15, 2009 by Mister25t

[SteveL]

Looks more like casting artifacts to me. I'm particularly suspicious of the crack theory when it would appear that the largest crack doesn't extend completely to the clutch fork hole (but that might be just the nature of the photo). If the bellhousing is so severely cracked to the extent that it affects clutch operation, you should be able to see the cracks open/close with operation of the clutch pedal.

Before having anything welded, you should have the cracking confirmed by an NDT specialist using dye penetrant or possibly even eddy current testing. Aviation industry specialists qualified to ANDT and CASA requirements are the best to use for this.

[Nathan76]

from those photos they just look like casting marks not cracks at all.

the only time i have seen a bell housing crack is when people rattle the bellhousing bolts up unevenly or with something caught inbetween block and bell housing

[2LV8ETR]

Got the same casting marks on mine. No probs here!

[Mister25t]

Aw yeah thats great news guys. Just me being bloody minded it looks like. I'm predicting that im going to have to drop the gearbox anyway so i didn't really take a good look over the whole housing to see all the marks everywhere. Thanks for the quick help and not burning me for being a dumbass. Just waiting on braided clutch line to arrive before i put the lot back together and see how it goes.