IVE HAD IT with this clutch system and manual gearbox!!

[1985 Ford F-150]

Bench bleedin is pumpin it with your hand while its off the truck.

 

[F 150Cobra]

Bench bleedin is pumpin it with your hand while its off the truck.

yupp i did that

 

[flareside_thunder]

how much did you pump it the first day?

 

[Old_Paint]

Umm, might not be the MC or the Slave at all. Is it possible you buggered the pilot bearing when you put the tranny in? Doesn't take much to do that if you get a little rough with it. Umm, you put the engine in recently, right? Did you use the right pilot tool to center the disk before you tightened down the pressure plate? You said the clutch only moves .5 cm or so. The clutch shouldn't move much, but the slave should move about 3/4 inch, or roughly 20 mm to release the pressure plate. I don't know if you can see that through the inspection holes or not. Never tried to see it.

Mine bled quite easily, actually. Just make sure you don't let the reservoir get low while you're bleeding. Couple of bleeds, then top off. I'm pretty sure I've seen a write-up somewhere on the proper bleeding technique.

Another thing to check, is will it start in gear? If it does, with the clutch released, there should be next to ZERO noise from that transmission. Put your ear on the back of your hand on the shift knob. If it's the pilot, you'll hear it LOUD and clear. The input shaft won't be turning if the tranny is in gear. Make sure to chock the wheels and set the P-brake really good before doing this. Just in case it does lurch because the clutch isn't released.

 

[surewhynot]

Jurgen, yours uses the integral slave/throwout bearing right? Do you have the proper pressure plate? IIRC, it should be a diaphragm style clutch.

 

[F 150Cobra]

Umm, might not be the MC or the Slave at all. Is it possible you buggered the pilot bearing when you put the tranny in? Doesn't take much to do that if you get a little rough with it. Umm, you put the engine in recently, right? Did you use the right pilot tool to center the disk before you tightened down the pressure plate? You said the clutch only moves .5 cm or so. The clutch shouldn't move much, but the slave should move about 3/4 inch, or roughly 20 mm to release the pressure plate. I don't know if you can see that through the inspection holes or not. Never tried to see it.

Mine bled quite easily, actually. Just make sure you don't let the reservoir get low while you're bleeding. Couple of bleeds, then top off. I'm pretty sure I've seen a write-up somewhere on the proper bleeding technique.

Another thing to check, is will it start in gear? If it does, with the clutch released, there should be next to ZERO noise from that transmission. Put your ear on the back of your hand on the shift knob. If it's the pilot, you'll hear it LOUD and clear. The input shaft won't be turning if the tranny is in gear. Make sure to chock the wheels and set the P-brake really good before doing this. Just in case it does lurch because the clutch isn't released.

what do you mean? with the tyresin the air will it start in first? or what do you mean?? no it wont start the truck starts moving

 

[F 150Cobra]

Jurgen, yours uses the integral slave/throwout bearing right? Do you have the proper clutch disc? IIRC, it should be a diaphragm style clutch.

this one i have

 

[surewhynot]

Yup, thats a diaphragm pressure plate.

 

[F 150Cobra]

waw what a relief...


the pressure plate BOLTS got loose... note to self
and now the truck shift buetifully

tomorrow im gonna take them out get new grade 8 bolts with lockwash and locktite!!

ALWAYS USE LOCKWASH AND LOCKTITE ON A HIGH PERFORMANCE ENGINE!!!!

 

[blackhat620]

waw what a relief...


the pressure plate BOLTS got loose... note to self
and now the truck shift buetifully

tomorrow im gonna take them out get new grade 8 bolts with lockwash and locktite!!

ALWAYS USE LOCKWASH AND LOCKTITE ON A HIGH PERFORMANCE ENGINE!!!!

Make damn sure you buy pressure plate bolts for your application. Do not just go to the Hardware store and buy bolts of the shelf. If you are going to upgrade your pressure plate bolts from OEM, you need to purchase ARP or other reputable manufactures High Performance pressure plate bolts. Prior to installing the bolts, thoroughly clean the threaded holes and bolt threads with carb or break cleaner before applying the Loc-tite. Torque the bolts to OEM specifications or if the A/M bolt manufacture lists a specific torque then you need to follow the A/M manufactures instructions.

You do not want to get this wrong, more than one driver has been killed or severly injured when a clutch/pressure plate/flywheel has had a failure. I have seen them come up through the dash and exit through the roof of the vehicle.

 

[F 150Cobra]

Make damn sure you buy pressure plate bolts for your application. Do not just go to the Hardware store and buy bolts of the shelf. If you are going to upgrade your pressure plate bolts from OEM, you need to purchase ARP or other reputable manufactures High Performance pressure plate bolts. Prior to installing the bolts, thoroughly clean the threaded holes and bolt threads with carb or break cleaner before applying the Loc-tite. Torque the bolts to OEM specifications or if the A/M bolt manufacture lists a specific torque then you need to follow the A/M manufactures instructions.

You do not want to get this wrong, more than one driver has been killed or severly injured when a clutch/pressure plate/flywheel has had a failure. I have seen them come up through the dash and exit through the roof of the vehicle.

first they where not OEM they where of the shelf hardware store bolts i guess thats why they fail in the first place..


gotta findout what thread they are and get these?
http://www.summitracing.com/parts/ARP-250-2201/?image=large

i can get those at a hardware store same type..

 

[1985 Ford F-150]

I used grade 8s and lock washers on mine and never had a problem.

 

[blackhat620]

I used grade 8s and lock washers on mine and never had a problem.

Problem with this is that pressure plate bolts are application specific, some have rounded shoulders and some do not. Also you have low profile heads and larger diameter heads. From a safety standpoint improper bolts can get deadly.

 

[1985 Ford F-150]

I dont understand how it could be unsafe if theyre tightened down properly and the heads are big enough to where it wont pull through.

 

[F 150Cobra]

i know what he means that the hole at the PP is a little bigger than the bolt size and could develop a little play in there...

but my pp is not like that its the same size as the bolts so im gonna get a bolt that looks like this

 

[1985 Ford F-150]

Yeah the hole on the pressure plate is a hair bigger but not that much.

 

[blackhat620]

I dont understand how it could be unsafe if theyre tightened down properly and the heads are big enough to where it wont pull through.

Well if you study the engineering of fastners, and in this case bolts, head diameter,, head thickness, thread pitch, shaft diameter, sholder detail, tensil strength etc all play a factor in fastener design and selection. Just because you went to a grade 8 bolt does not mean it is safe. If the bolts tensile strength, shear capacity or hardeness are incorrect for the intended use you can get premature fatigue failure. For example if a fastener is to hard it may crack prematurely do to the loads it sees. Harder is not always better because as it the metal gets harder it also becomes more brittle. As for head size, what calculations did you use to determine the head size was sufficient?

 

[LEB Ben]

Well if you study the engineering of fastners, and in this case bolts, head diameter,, head thickness, thread pitch, shaft diameter, sholder detail, tensil strength etc all play a factor in fastener design and selection. Just because you went to a grade 8 bolt does not mean it is safe. If the bolts tensile strength, shear capacity or hardeness are incorrect for the intended use you can get premature fatigue failure. For example if a fastener is to hard it may crack prematurely do to the loads it sees. Harder is not always better because as it the metal gets harder it also becomes more brittle. As for head size, what calculations did you use to determine the head size was sufficient?

Ahhhhh...all the stuff Dad always tried teaching me when I worked in his die shop comes flooding back. Apparently, I didn't blow him off as much as he thought I did.


That is all...and please continue.

 

[1985 Ford F-150]

I just got the old bolts that were in pretty sad shape and went down to Napa and matched em up with some grade 8. I do understand that as they get harder they are more brittle but a grade 8 is very hard to break.

 

[blackhat620]

I just got the old bolts that were in pretty sad shape and went down to Napa and matched em up with some grade 8. I do understand that as they get harder they are more brittle but a grade 8 is very hard to break.

Not if the fastener is to brittle for the application. Case in point, A/M High Strength head studs for the 6.0 PSD. Some of the A/M head stud manufactures jumped on the band wagon of harder/stronger is better, well that proved to be false in short order. The High Strength head studs were shearing off/breaking from rapid fatigue because they were to brittle. These studs have been discountinued. Now ARP stood back and studied the head bolt/stud problems with the 6.0 PSD and came out with a great retrofit that works, but they must be installed exactly to manufactures specifications and specified head gasket to prevent catastrophic engine failure or premature head bolt/stud failure.