Need some Velvet drive help.

[yorklyn]

I'm hoping raising the rpm up will help some. good to know I'm not the only one with this noise and even better hearing that people have been running with the rattle without issues!
Crossing my fingers!

[rickalan35]

Hi Todd, You have no doubt been all over the net searching for an answer to your velvet drive rattle issue. I happened upon this chain and will list it here in proper order. Might help. Rick

I have a Velvet Drive 1.52:1 transmission on my 83 stars and stripes. When I bought the boat the transmission had water in the fluid. I drained it twice and refilled with Dextron III. When the boat is first put in gear with the RPMs just off idle there is a rattle in the trans. As the RPMs come up the rattle stops. It is worse in reverse than in forward. The rattle sounds like loose parts and seems to come from the rear of the trans. I have also noticed that the trans does not start spinning until the RPMs come up a bit. It does not start spinning as soon as you put it in forward. You have to advance the throttle a bit in order to get it to start turning the prop. Not the same in reverse. Any transmission gurus out there!

Increase the Idle RPM a little and see if the rattle goes away. The clutch plates are forced together by oil pressure from the oil pump in the trans. Low RPM will not let the oil pump produce enough pressure if it is somewhat worn and lack of sufficient oil pressure will let the clutch slip a little causing the planetary gears (reduction gears) in the trans to rattle. If increasing the Idle RPM doesn't fix the problem, check the damper plate. Did you find out why there was water in the trans?

Make sure the noise is really from the trans and not a worn/broken spring on the damper plate that bolts to the flywheel.It will make the noise only at idle

I'd check the damper plate first off. My 86' did this when I bought it. Bought a whole new trans for it thinking that was what it needed. When I tore it apart I realized it was the damper plate. Needless to say the boat got a new trans and damper plate.

[yorklyn]

Thanks Rick!
Thats actually one of the first ones I read after Mike suggested I google the issue. Thought it was funny that the description of the issue,

"The rattle sounds like loose parts and seems to come from the rear of the trans."

Was the exact description I would have used.
May try to run down tomorrow night to mess with it, if not then ill be working on it saturday.

[yorklyn]

Update:
Double checked all plug wires and everything was correct. adjusted the rpms up to 750 idle in neutral and the sound all but went away!!!
Of course I now have a slight tranny leak at the flange seal and a oil leak at the intake manifold ! aghhh
actually ran the boat up the sassafras river up to the bay (1hr round trip). Stopped a few times to mess with the packing glands but the boat ran great. 19mph at 3000 rpm and 22-23 at 3300.
I believe the tranny leak may be from the engine alignment being slightly off. no vibration but I checked it with a feeler gauge and it needs some tweaking. Hoping the intake leak will disappear after I re torque the bolts down, if not its easy enough to pull and re seal it.
Thanks for all the help troubleshooting the velvet drive guys!

[BobCT]

Todd,

Did you use the intake manifold end pieces or just use RTV? I used just RTV on the ends (this time) and it's been leak free. The back end near the H/E is sort of an issue on the 454's. A slight snug up might just fix it. Had the same issue when I rebuilt my trans last year. The output seal immediately leaked for no plausible reason. I put about 4-5 hours and it stopped and never leaked again.

So worth a shot to let that go for a bit. For now, here's a trick I used. Put some spray adhesive on the back of an oil absorbent sheet and stick it to the bilge under the leak. It'll stay in place and you could deal with it in the fall. I'm doing that now on my port oil filter housing. You just need a little bit to keep it in place and the it peels right off.

Bob

[yorklyn]

the machine shop used a product called "the right stuff", its an awesome product
http://www.permatex.com/products-2/prod ... ker-detail
naturally it leaks on me! Lol!
I like the idea of the spray adhesive to hold the oil mat in place, thanks!
im thinking the slight tranny leak could be caused by the slight mis alignment putting more pressure on one side of the seal and creating a gap on the other??? they need to be aligned anyway so ill wait and see.
BTW Bob, Thanks a million for the part # on those led lights, they fit perfectly and put out a ton of useful light! it hurt a bit paying $170 for 10 bulbs but after seeing them in action they were well worth it!!! no more burning hot bulbs!!!!