overdrive?

[whydidistartthis]

Can the over-drive give similar symptoms as a slipping clutch?
This is not a consistent problem. Sometimes can drop the clutch, causing sound and a little smoke as the tires struggle for grip!

Other times lots of engine noise, and not a lot of forward progress!

I have changed the gearbox and now have this problem that was not there before.(gearbox was noisy).

Any thoughts anyone?

[cliftyhanger]

http://www.canleyclassics.com/technical ... overdrive/

have a read....

[whydidistartthis]

Thanks, food for thought.

Looks like the box will have to come out again! I guess removing the overdrive unit with the box still in the car is a no go?

[Jon Tilson]

Its doable on an 1850 but I found it impossible on a Sprint once when I tried having done it to an 1850 before.

I guess it may be possible if you can lower the subframe.

Jonners

[covcourier]

We have the same problem on our 1500HL with overdrive.

Get the symptoms of clutch slip in second when accelerating quickly. If you let the clutch up then get on the power it is ok but if you are on the throttle too quickly it just goes nowhere and you need to ease off then go again gently.

[tony g]

My sprint had the same symtoms. It is down to the one way clutch or also known as a sprag in some circles. later overdrives had a revised sprag and these give the trouble. Reverting back to an older type fixes it. Speak to overdrive spares for a better idea of whats needed. http://www.odspares.com/

Tony

[Jon Tilson]

Sorry but that's cobblers.

If your one way clutch is lunched then it makes horrible clicking noises. It cant slip....trust me.

It either transmits drive or it doesnt.

If it slips its because you have burned out linings on the cone clutch. Last time I thought about having one
relined a complete exchange overdrive was a similar price.

It can originally be caused by sticky valves and dodgy O rings, blocked filters and old oil, bit if its allowed to persist
the cone clutch soon wears out. Its not meant to slip much.

If yours has only done it once or twice, change the oil and filters and all the small O rings you can get at under the access cover. It may survive but its no more than a 20% chance.

Jonners

[tony g]

You clearly don't know how a one way clutch works John. Its a very smooth action and the angle of the ramps is critical for operation. If you speak to someone who knows o/d's inside out you will be told the same thing.
The problem here isn't a friction lining problem as it would slip in all conditions. When the one way clutch is faulty as in this case, you can have drive all the time but now and then when pulling away with a bit of urgency (as in the op's description) the one way clutch CAN slip without noises and you lose all drive, as if in neutral.

Tony

[tony g]

Half way down the second paragraph..

http://www.canleyclassics.com/technical ... overdrive/

Tony

[stokieat75]

Had this same problem on my 1500hl two years ago after converting to overdrive from non od and I can confirm it is the one way roller clutch, when I took mine out after stripping the unit the rollers were quite badly grooved and that I think is why it slips, after replacing it I have had no problem. I have done about 5000miles since then. You can take the of unit off with the gearbox in place I think. There was slight glazing of the cone linings and I cleaned it up with fine wet and dry used dry.

[whydidistartthis]

Sounding like a slightly thorny issue..

Car won't get much use over the winter, but might check out the filters and o/rings. It can't do any harm....can it?

Thanks for the advice. Will try and report back, if I get some results....

[wimpus]

Had this same problem on my 1500hl two years ago after converting to overdrive from non od and I can confirm it is the one way roller clutch, when I took mine out after stripping the unit the rollers were quite badly grooved and that I think is why it slips, after replacing it I have had no problem. I have done about 5000miles since then. You can take the of unit off with the gearbox in place I think. There was slight glazing of the cone linings and I cleaned it up with fine wet and dry used dry.

Any pics of when you where doing it ??

On my Spitfire 1500 i have problems with the O/D also.
Slips in 3rd only and only when it's hot outside (around 25° or so)

[Jon Tilson]

Fair enough...

I've only ever had the worn out linings issue. Guess I must have been lucky then. Its not a problem I have had
more than 5 times on various early 1850 dolomites so maybe I've never seen the later weak one way roller clutch.
I have rebuilt one or two with new rollers using the big cable tie method to replace the special tool. Bit of a fiddle...

The horrible clicking noise comes if you try to reverse in a car in which o/d has failed to disengage. I've had this on 2 cars
but obviously stopped quickly enough to not be terminal. Sticky solenoids after long lay ups were to blame. Luckilly it cured itself with more use.

Jonners