McLeod bolton HTOB problem

[67redrocket]

Hello I have a McLeod hydraulic throw out bearing on my toploader transmission. Its almost new, and Iam guessing its something wrong with it. Iam wondering if someone else have had the same problem.



When I press the clutchpeddal with high rpm on the engine on second gear, the clutch dont release and the pedal is stuck in the floor. After some seconds the pedal comes back from the floor and everything is back to normal.

Since this only is a problem with high rpm i guess the problem is clutch/HTOB related. And since the cluthc dont release when the pedal is pressed i guess the piston on the HTOB hasnt moved. Iam thinking that the hydraulic oil in the HTOB is leaking past the Orings and to the other side of the piston somehow.

Any ideas?

[andrewb70]

Are you loosing hydraulic fluid in the system? Any wetness under the bell housing?

Andrew

[67redrocket]

Are you loosing hydraulic fluid in the system? Any wetness under the bell housing?

Andrew

No nothing, everything is dry.

[andrewb70]

Did the McLeod instructions tell you to space the bearing a certain distance from the clutch spring fingers?

Andrew

[67redrocket]

Did the McLeod instructions tell you to space the bearing a certain distance from the clutch spring fingers?

Andrew

Yes, i think was between 0.1 and 0.3 in, cant really remember.

I have talked with mcleod and they say there is probably a problem with the clutch, that this is a common issue with some diaphragm style pressure plates. When you go above 5500 RPM the centrifugal forces keep the diaphragm spring held down which will not allow you to shift until the RPM is lowered.

The thing is that this was not a problem before i installed the mcleod 1304 HTOB. Iam not shure if I want to change my HTOB or my clutch

[Red67Mustang]

I thing this has to do with the "over center" point on the clutch fingers vs pressure plate. I don't know the full details but have heard of this in the past when a mis-adjusted clutch bearing compresses the fingers too far... The complaint is that the clutch doesn't return as quick as it should. You should have plenty of disengagement though. Try pressing the pedal only enough to shift (not to the floor) and see if that makes a difference.

[andrewb70]

I thing this has to do with the "over center" point on the clutch fingers vs pressure plate. I don't know the full details but have heard of this in the past when a mis-adjusted clutch bearing compresses the fingers too far... The complaint is that the clutch doesn't return as quick as it should. You should have plenty of disengagement though. Try pressing the pedal only enough to shift (not to the floor) and see if that makes a difference.

This can very well be happening.

I would jack up the car and get a buddy to help. With the engine off and the car in 4th gear, have a buddy press on the clutch very slowly. As he is doing that, grab the driveshaft and put a rotating force on it. With the clutch engaged you won't be able to turn it, but as the clutch is slowly released you should be able to start turning the driveshaft by hand. Note the position of the pedal when you are able to turn the driveshaft by hand. Have him continue to press the clutch further and if it starts getting harder to turn the driveshaft again, you are indeed over traveling the clutch.

Is there an access panel in the bell housing? If so, you should be able to check the air gap between the flywheel and clutch disk using a feeler gauge. The required gap will depend on the style of clutch disk material, but most manufacturers recommend .090" with the typical street style clutches. If you have significantly more or less, that's a problem.

Andrew