What does intermediate shaft do?

[threeOh]

I just had one go through the block with a truly ugly sound. Odd thing is the car never skipped a beat and I was convinced the sound was from another vehicle. Drove another 30 miles just fine, pressure and temp normal.

Once the engine was turned off oil simply flowed out. Not a spot of oil on the undercarriage so I assume negative engine pressure kept me from losing it.

New engine on the way.

What does this shaft do? I thought perhaps the oil pump but I maintained pressure.

[PTEC]

I just had one go through the block with a truly ugly sound. Odd thing is the car never skipped a beat and I was convinced the sound was from another vehicle. Drove another 30 miles just fine, pressure and temp normal.

Once the engine was turned off oil simply flowed out. Not a spot of oil on the undercarriage so I assume negative engine pressure kept me from losing it.

New engine on the way.

What does this shaft do? I thought perhaps the oil pump but I maintained pressure.

The intermediate shaft does indeed drive the oil pump. Generally when intermediate shafts break, its not like it breaks in half. What happens is a small stud which protrudes from the much maligned intermediate shaft flange seal breaks off an goes flying around in the bell housing. If you take a look at some of the pictures people have taken of the flywheel side of the engine when the transmission is off, you can see a 13mm nut centered in the intermediate shaft flange seal, that nut and the stud its affixed to break. Oil pours out of the hole left in the middle of the flange seal.

The crank is still driving the intermediate shaft therefore you will still have oil pressure. The other purpose of the intermediate shaft is to drive the camshafts. One end of the intermediate shaft has two sprockets and the other has one. The end with two has one for the drive chain from the crank, and the other drives the cams.

Edited November 21, 2005 by PTEC

[threeOh]

PTEC,

Thanks for the reply. The leak was -- at least appeared to be -- right above the bellhousing.

I now understand the maintenance of oil pressure and the fact the valve train seemed ok. A few hours after it happened a retired F1 mechanic for Lotus and his son, a piston engine airplane mechanic dropped in. We had a heck of time coming up with explanations. The intermediate shaft was immediately eliminated as we believed it probably drove the oil pump.

Have to hand it to Champion as well P. Called in about 7 am and the car was picked up within minutes. I called a few hours later to see if they knew the car was there and a new X51 was already on its way.

[PTEC]

Thanks for the reply. The leak was -- at least appeared to be -- right above the bellhousing.

Yep, oil will puke out of the intermediate shaft flange and right out into the bellhousing. It'll look almost like a HUGE rear main leak.