No neutral on Velvet Drive

[TCdave]

Hey Crew,

After falling in love with my bu, a buddy of mine sold his Moomba and bought a 96' Sportster Flightcraft. At some point the engine was upgraded from the stock 265HP 5.7 to a 99' 310HP carb 5.7. The boat looks and runs well except that it drifts forward while in neutral. I adjust the linkage to no avail last night. I then too the shift cable off of the transmission and shifted it by hand. When the lever is in the neutral position the shalt still turns but much slower than it does when in the forward position.

The fluid appears to be full and is clear, like brake fluid. I understand that these transmissions will tolerate a range of fluids but which one is the best given its age?

I have downloaded a copy of the manual.

Model # 10-17-004

Ratio 1:1

Thanks

[oldjeep]

If you google it you will find it is a pretty common issue. Two main causes seem to be slightly warped clutch plates and leaky seal in selector valve.

[2014Skier]

What OJ said. The only way to test for a leaky selector valve is to hook up a pressure gauge to the forward clutch pack pressure port and measure it. The plates could be warped too, that would require a rebuild. From the fluid standpoint sounds like gear oil, which is quite thick and could be creating drag in the clutch pack. Type f atf which you could also run is gonna be thinner. Though changing over to a different fluid could be challenge ad you don't really wanna be mixing two types and getting all the existing fluid out would require multiple flushes and even that would take a bunch to get the existing fluid out of the clutch cylinders.

Edited September 4, 2015 by 2014Skier

[Woodski]

@TCdave: I have run both 30 wt. hydraulic oil and ATF and prefer the hydraulic oil due to reducing the clatter at low speeds. The hydraulic oil seems (my experience) to act just a bit more like a damping fluid and makes the box a bit quieter. Either work. If you drain to change, don't forget to drain the transmission cooler and lines (that is actually really easy and you can basically lift it up above the trans and let gravity do its thing). I use a cheap transfer pump (~$5) from Harbor Freight to suck the fluid out of the unit.

[TCdave]

Thanks for all the replies!

We are changing the fluid over to type F this. Weekend. If that doesn't help, the owner has already located a rebuilt one from a shop in VA for $700.

[TCdave]

Update- a buddy of ours replaced the shaft packing on this boat as it was leaking pretty bad. This also fixed the transmission issue (or hid it) as well.

[Woodski]

@TCDave: assuming the seal was the only change, the drag of the new seal is stopping the creep. I would certainly frequently check the shaft temperature, simply by touch, to make sure it is not getting too hot while spinning.