TKO600 clutch

[twobjshelbys]

Originally Posted by twobjshelbys

Here is the status. Scott did the mechanical adjustment and then drove it and said it faded when he was driving it. I've noticed that it seems to come back if I pump it. He said the same thing. So when I went back to the shop this afternoon I pumped it - and after about the 10th cycle it was flat to the ground.

We're thinking Clutch Master Cylinder....

Does anyone know what the equivalent part for a CSX roller would be? I've got a call in to Shelby Autos but if I can get a cross part number I might be able to find it locally. I was planning on taking it to a car show (and they were psyched! but if I can't find one tomorrow and get it FedEx'd overnight I'll be out.)

A little more info - I'm going from the info Scott told me, but the clutch master cylinder has two lines going to the clutch slave, and the reservoir is remote. Does anyone recall this kind of setup?

[patrickt]

Originally Posted by twobjshelbys

A little more info - I'm going from the info Scott told me, but the clutch master cylinder has two lines going to the clutch slave, and the reservoir is remote. Does anyone recall this kind of setup?

I don't know a whole lot about CSX cars, but does the outside of the cylinder tell you anything obvious, say Willwood 7/8" or the like? Or is just a no-name?

[twobjshelbys]

Originally Posted by patrickt

I don't know a whole lot about CSX cars, but does the outside of the cylinder tell you anything obvious, say Willwood 7/8" or the like? Or is just a no-name?

I was pointed to this by HST:

http://www.cncbrakes.com/mc.asp?grp=...712&subseries=

Thanks Jean!

[patrickt]

Originally Posted by twobjshelbys

I was pointed to this by HST:

Thanks Jean!

There are five different bore sizes on that page -- you need to get the right one. Any chance you could snap a quick pic of the MC that is on your car and post it?

[Eljaro]

I drove the car again after tightening the six 5/16 bolts of the pressure plate.
I checked them again yesterday after a ride. They were not as TIGHT as they should be. So there is some movement there which looses them up.
So I bought six socket head screws in DIN 12.9 strength (which is higher than grade 8) with shoulder. The 30mm long screws did not have shoulder, so I had to buy the 40mm long ones and cut them to size. I used hardened steel washers since the head of these screws are very small and tend to sink into the pressure plate metal.
I also used blue locktite and tightened to 28 lb/ft.
I will have regular checks on these screws, easy to do through the fork hole.

This is one disadvantage of aluminum flywheels I was not told about.

Regarding twobjshelbys problem, it is either the master or slave cylinder.
If by pumping the pedal the line purges itself empty it is probably the master cylinder. It happened to me once when I wrongly used DOT 5 brake fluid. The inside of the cylinder got corroded and leaked past the piston.
Disassemble the master cylinder ( depending on your setup you can do that without removing it from the car) and check visually.

[elmariachi]

You guys really know how to keep a guy up at night wondering if he used the right bolts and got them tight. I have a 427 FE/TKO 600 with a McLeod 11" clutch and 11" PP setup from Brent Lykins, along with a Fidanza aluminum flywheel. The McLeod PP came with 5/16ths grade 8 bolts, and McLeod said to mount them with blue Loctite and NO washers, so that's what I did. I checked them as a result of this thread and they are muy bueno.

Great Asp, I have noticed that a speed shift from 2nd to 3rd with my TKO 600 is dicey. I am hoping its just me getting used to the narrow entry gate. I may give myself one of Brent's Steeda TKO shifters as a Christmas present. He tells me it'll make me shift like Don Prudhomme.

[blykins]

Thanks to Patrick and Rodger for bird-dogging all of this. It's all very good information and that's what makes this site worth-while. I will be sure to take all of this into consideration with the next aluminum flywheel combo that I sell.

Great Asp, I can set you up with a new clutch kit, custom for your application, wants, and driving style. Just shoot me an email and we can talk at length about it.

elmariachi.....I won't make any promises. Wait, does Don Prudhomme even shift during a run?

[lovehamr]

Originally Posted by blykins

Wait, does Don Prudhomme even shift during a run?

Not since about 1968!

[patrickt]

Originally Posted by elmariachi

The McLeod PP came with 5/16ths grade 8 bolts, and McLeod said to mount them with blue Loctite and NO washers, so that's what I did.

They provided their own fasteners? Do you happen to remember whether they were shouldered bolts? The only reason they would specify no washers would be to increase the fastener depth (which would seem to indicate they are aware of the issue). It would be nice if someone with a Fidanza aluminum flywheel could measure the depth of the shoulder hole and post it. From the factory, did Ford PPs come with washers under the PP bolts?

[patrickt]

Originally Posted by elmariachi

You guys really know how to keep a guy up at night wondering if he used the right bolts and got them tight.

Here's something to think about while you're not sleeping... I'm advised that, from the factory, FE pressure plate bolts had washers under them. I'm further advised that both ARP and Mr. Gasket replacement OEM PP bolts are both shouldered and come with washers (and that includes the "good" ARP bolts and the "great" ARP bolts). I am also told that the McLeod Street Pro plainly says that it "uses stock pressure plate bolts," which are not included. The Super Street Pro says that it "includes pressure plate bolts." The RST and RXT Installation Instructions specify the use of "your stock pressure plate bolts." Nowhere on their forums, installation instructions, or web site do they discuss the use of a shouldered PP bolts. I'm betting that, for them to provide you with PP bolts and to specify that you NOT use washers, those bolts not only are not shouldered, but probably have dubious thread depth as well. The only way you'll know for sure is to pull one of them out and look at it. You should be able to tell from the caked goo on the thread how deep they were in, but if not, a little dye would answer that question. Spotting the shoulder (but I bet there isn't one) will be really easy. Sleep tight.

[elmariachi]

Originally Posted by patrickt

They provided their own fasteners? Do you happen to remember whether they were shouldered bolts? From the factory, did Ford PPs come with washers under the PP bolts?

Yes, they supplied 5/16"-18, 3/4" in length, no shoulders. Steve Christ's rebuild book references bolts and lock washers in the clutch reassembly process.

Originally Posted by patrickt

I'm betting that, for them to provide you with PP bolts and to specify that you NOT use washers, those bolts not only are not shouldered, but probably have dubious thread depth as well. The only way you'll know for sure is to pull one of them out and look at it.

I removed one and it appears that the bolt was threaded into the flywheel a tad under 1/2". All six of them very tight when I checked them. I think changing bolts is a bit of overkill for my street application but what would be the ideal bolt??

[patrickt]

Originally Posted by elmariachi

I removed one and it appears that the bolt was threaded into the flywheel a tad under 1/2". All six of them very tight when I checked them. I think changing bolts is a bit of overkill for my street application but what would be the ideal bolt??

Honestly, I wouldn't touch them. I have heard of every type of driveline failure there is in Cobras. U-Joints, Transmissions, Differentials, Rear Ends, even twisting axles so that the white line on them looks like a barber's pole. I have never heard of pressure plate bolts shearing off. Coming loose and falling out? Maybe... but not shearing off.

[patrickt]

... but if you're really worried about them you could always safety wire them to the bell housing.

[patrickt]

Originally Posted by elmariachi

Yes, they supplied 5/16"-18, 3/4" in length, no shoulders.

Ford OEM bolts (Mr. Gasket & ARP, too) are 5/16"-18 x 1" -- but they're going to have the shoulders on them. If those shoulders bottom out in to your flywheel then your pressure plate is not going to be tight no matter how hard you torque them down. If you have half an inch of thread grip on a 5/16" bolt, I'd leave it alone. I really would like an answer though from McCleod on exactly what it is they're doing with their bolts.

[elmariachi]

I JUST spoke with Lee at McLeod. They have confirmed with Ron Fruchi (sp?) at ARP that the correct bolt to solve this issue is either the ARP 150-2201 or 250-2201, depending on the strength bolt you want to use. You MUST have a shouldered bolt that takes advantage of the counterbore in order to achieve reference, provided you have no dowel pins to create reference.

He says the bolts I have were not supplied by McLeod but by Fidanza, though I do not think that is right because I bought my Fidanza new from a local guy but there was no box, only a shrink-wrapped flywheel and paperwork, and no bolts. Regardless, we now have the McLeod recommendation.

[patrickt]

Originally Posted by elmariachi

I JUST spoke with Lee at McLeod...

How are you going to check that the shoulder bore depth of your renegade flywheel is to OEM specs?

[elmariachi]

I am talking to Fidanza now....

[patrickt]

There is an apparent discrepancy in the lengths of the ARP and Mr. Gasket PP bolts. Page 178 of the Mr. Gasket catalog has them listed at 1 inch. Rodger reported that he measured the ARP bolts at .75 inch. Here is a length to the Mr. Gasket catalog. http://www.mr-gasket.com/pdf/Fasteners.pdf

EDIT -- I guess Mr. Gasket could be including the size of the head in their numbers....

[elmariachi]

According to Aaron at Fidanza, the Fidanza flywheel has three different bolt patterns, two for pressure plates with for 5/16" bolts and one for 3/8". The counterbore measurements are as follows:

- 3/8" bolt pattern, depth is .20 and width is .375

- 5/16" bolt pattern, depth is .20 and width is .312. This is the pattern my long style McLeod 360500 uses.

Aaron says these FE flywheel counterbore dimensions would have been derived from the original steel flywheel. I have my original R-code flywheel in the garage and I see absolutely no counterbore.

So I guess I will get the thickness of the McLeod pressure plate at the bolt hole, call ARP and do some math.

[patrickt]

Originally Posted by elmariachi

So I guess I will get the thickness of the McLeod pressure plate at the bolt hole, call ARP and do some math.

Just in case you were dozing when we went over that in math class...

D = Basic Diameter.
p = Screw Thread Pitch
Le = Length of Thread Engagement
A t = The screw thread tensile stress area
d p = Pitch circle diameter of thread
A ss =The thread shear area

The following formula for the Tensile Stress Area of the (male) screw