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Slight transmission noise - reverse?
Gergely - 14/7/09 at 01:39 PM

Hi, we had our R1 engined MNR out testing during the weekend. Everything is fine, the car drives brilliantly, the engine is fine, although needs setting up and rolling roaded.
We have covered around 60 miles during the weekend, not much, but we wanted to check everything, make sure all is well.
At the end of the last outing (public roads only, no track yet) at constant engine speed we realised a slight vibration and "Rrrrrrrrr" noise from somewhere in the transmission. The noise and vibration goes away if you back off the throttle. We stopped and checked all prop bolts, diff mounts, but everything seems tight and well. None of the markings on the bolts have moved.
I feel no play in the props, half shafts either.
When getting back in the car, the noise seemed to have disappeared... but after another half a mile, it came back, so we slowly limped home.
Unfortunately work schedule meant I could not look at it just yet, but I was thinking... could it be that the Quaife reverse spat its oil out and running with very little - if any - oil? We have experienced oil being spat out before, so now we fitted a catch tank, but have not refilled the box ever since installed (around 80 miles in the box total)...
I will take a look and fill up the box this evening, but maybe someone has any other ideas what to look for before I go for a test drive? Electrical connections or handbrake lines fouling something, etc.... ?
Thanks!
Gergely


Gergely - 15/7/09 at 08:27 AM

Took the tunnel cover off and it was the front propshaft (engine to the Quaife reverse), reverse side mounting bolts that all worked loose and one of the four actually fell out!
Lucky that nothing else happened.
The problem with the Quaife flange is that it is a cross shape instead of the propshaft's circular shape, so practically nothing else than the four bolts transmit the full power of the engine to the wheels... And there is only around 8mm thread in the flange, which we have Loctite'd but it was not enough...
We will now have some bolts made that have no thread at the head for 5mm (the propshaft flange part) and we will use a stronger loctite to secure the thing in place...
I broke down in sweat just thinking about what could have happened...


kjouk - 15/7/09 at 09:35 AM

Have look at k-nuts, had this problem many times on a westy reverse box but not since fitting these although they are a bit pricey.

Kev