Possible mismatched clutch components?? or what??

[defecater]

Recently got done swapping out a bad E4OD for a T-19 behind a 7.3 in a 93 F-350. I sourced the transmission, bellhousing and flywheel from an 85-86 ish F-250 with the 6.9, and bought a new clutch kit from the local parts store. For the pedal assembly and hydraulics, I went to the local junkyard and pulled them from an 92-97year of truck with obviously a ZF 5 speed.

I did notice two things about the pedal assembly that I didnt like- the nylon bushings that the crossrod rides in were worn/unseated, and the side of the assembly that the master cylinder attaches to through the firewall had apparently been broken loose at some point and someone did a crappy job of welding it back together. I managed to scrounge up some steel tubing with just the right inside diameter, and permanently welded in some support sleeves to replace the bushings. Didnt do anything about the welds, as even though they look crappy, it appeared to be straight and has plenty of quantity to suffice for quality.

Anyway, my problem is that the clutch will not disengage entirely. Is it possible that I have some sort of mismatch in the parts that are keeping this from happening?? I could be totally wrong on this, but it seems to me from my past experiences with Ford hydraulic clutch setups, that the external end of the fork looks like it is too far back, plus, when I installed the slave cylinder it popped easily into place, whereas all others I have done that I can recall were real mothers to get the rod pushed in and the slave seated in the bellhousing bracket.

Or is there something else I am overlooking???

 

[65sixbanger]

Try adjusting the clutch push rod. Take it off and unthread it 1/4'' or so and give it another try. I am assuming you bled the clutch system right?

 

[harleyjohn45]

Try adjusting the clutch push rod. Take it off and unthread it 1/4'' or so and give it another try. I am assuming you bled the clutch system right?

Not trying to steal the thread here, but I have a 91 superduty with a ZF5 and my clutch drags. Are you saying i can adjust the clutch push rod? Is it a big deal, I sure would love to add another quarter inch to the length of the push rod. I have to keep the clutch pedal all the way to the floor to change gears and I can tell its not releasing all the way.

 

[towcat]

Not trying to steal the thread here, but I have a 91 superduty with a ZF5 and my clutch drags. Are you saying i can adjust the clutch push rod? Is it a big deal, I sure would love to add another quarter inch to the length of the push rod. I have to keep the clutch pedal all the way to the floor to change gears and I can tell its not releasing all the way.

f450's don't have the adjustable pushrods.
you have a problem with either worn out bushings in the pedal assy or worse yet, a cracked firewall.

 

[DragRag]

Nice Avatar Cal....

 

[harleyjohn45]

f450's don't have the adjustable pushrods.
you have a problem with either worn out bushings in the pedal assy or worse yet, a cracked firewall.

Thats what I was told, but I've been told a lot of things. Thanks for the reply. Another thing about 450's is they also use a transfer case on the rear of the transmission that accepts the emergency brake assy and the transfer case won't come off the transmission. I have a bad bearing in the rear of the transmission and parts are hard to find for my year model.

 

[RLDSL]

Assuming the fork is on the ball correctly in the bellhousing and the firewall is intact, you can get a replacement adjustable clutch rod for the master cyl from napa for a few bucks that will solve your problem. Adjust it to where you have 1" free play before the throwout contacts the fingers and 1" up from the floor before it starts to grab and you will be in business

If you have the type of starter cutout switch that goes around the clutch rod, you will need to grind the end of the slot out a bit for the nut of tthe adjustable rod to fit down into it, and the whole assembly will have to be stuffed from the engine side with the switch attached

 

[defecater]

I was going to try bleeding the system like someone else posted in another thread- removing it all and bleeding it with the slave above the master. I was aware of the adjustable master rod, but I am reluctant to try it, because I don't think I should need it- the truck was an autountill I put this 4 speed in, so the firewall is intact.

I just keep coming back to how far back that throwout bearing arm is. I also noticed today while "brainstorming" that the pushrod on the slave is sticking out of the dust boot about 3/4 of an inch more than it apparently was when it was on the truck at the junkyard based on the amount of clean and shiny rod now visible that used to be inside the boot before.

I am afraid that if I am correct about there being something mismatched about the components, and I start messing around with adjustable pushrods and such, that I will cause something to go past the limits of its travel- push the throwout bearing off the end of the input shaft snout, or blow the piston out the end of the slave cylinder.

RLDSL- I am very skeptical about your statement of setting the throwout bearing an inch away from the clutch fingers. That would work with an old school mechanical clutch linkage, but all the Ford hydraulic clutch setups I have worked on in the past had the throwout bearing in constant contact with the clutch fingers because of a spring inside the slave cylinder.

 

[RLDSL]

RLDSL- I am very skeptical about your statement of setting the throwout bearing an inch away from the clutch fingers. That would work with an old school mechanical clutch linkage, but all the Ford hydraulic clutch setups I have worked on in the past had the throwout bearing in constant contact with the clutch fingers because of a spring inside the slave cylinder.

An inch at the pedal does not translate to an inch at the bearing. The bearing and the clutch itself move very little The fork is a lever on a fulcrum, exact ratio I couldn't even venture to guess but picture it in your head for a minute and the light bulb should go off. An inch at the pedal does not equal an inch at the bearing it is more like 1/8 of that ( remember Archemedes folks . The bearing sits real close but should never ride on the fingers or you would be eating throwout bearings on a bi-monthly basis. That is a non sealed bearing in there if it were running full time you would eat the things

 

[Agnem]

Get a hold of a service manual. There is a spec for the distance the slave cylinder rod should move, and you can compare what you see to the spec, to decide if your problem is upstream or downstream of the slave cylinder.

 

[harleyjohn45]

Thanks for all the feed back, I've been very busy and have not had time to mess with this old truck. I did go buy a new clutch cylinder and a new slave. Hope to get them in this weekend. The fire wall looks perfect, no flexing there. The clutch pedal does have some slop from side to side, so I will replace the bushing there, if it has one. I have not had it off yet. The clutch rod does not seem to have much play, so I hope the master and slave cylinders take up the slack. They don't leak, but they don't seem to be doing much. The clutch as always caught right at the bottom, but now it is not fully disengaging. I have a manuel for the engine, but not for the truck chassis. I'll try to locate a ford CD or something on that.
thanks again

 

[CESMITH]

Is the master and slave from aZF 5 the same as aT19 could there be issues with length makes you think mecanical is the way to go. I made my slave cylinder in the lathe at work , I was tired of changing junk

 

[defecater]

I had time to do some investigating on mine yesterday and could find nothing conclusive yet. I did not have anyone to push the clutch pedal while I took measurements though. I did measure the ZF slave I am using and compared it with the the T19 slave and a couple of 460/zf slaves- they all are pretty much the same length, but I dont know about internal diameter. I am going to see if the parts store lists different slaves by application in the next couple of days.

 

[CESMITH]

I kept blowing slave cyls. onmy 93, the NAPA guys wanted me to put on a larger dia. slave ,so i did I couldnt get enogh stroke out of it . natturlay they wanted me to buy anew master cyl. that is when I ordered a new master from CNC in califorina its all aluanum and made a steel slave out of bar stock .I used the guts and seals out of one of the originals I had. I beleve it to be 25mm bore . my master is3/4 bore . the ones on the 86 are larger and i havent had any problems yet.

 

[Agnem]

The clutch hydraulics are the same for all the IDI family.