Clutch issues

[CarlB]

I have a 1999 Zetec S-3 and broke the clutch at VIR. I contacted the clutch pressure plate manufacturer (LUK) and they told me the part number from the numbers on the pressure plate. When I got the new clutch it was 9 1/2 inches and the old one was 9 inches. LUK said it was superseded and it did bolt on. When I got it all together it was slipping badly. It appears the throw out bearing isn't letting the clutch engage completely. I am desperate to make it to NJMP!! Any help or good people to speak to would be greatly appreciated. 

[Croc]

 

Sorry to hear of the misfortune Carl.  Given my Caterham is engine out as of today, I know the feeling.    I am on the wrong side of the Atlantic for 2 weeks to get near my T-9 documentation but...

 

@S1Steve had a write up on zetec/T9 clutches that I have in my files but never digitized.  I recall it having parts numbers and suppliers.  Calling Steve to this thread.

 

Hail Mary option - I have not bought a zetec T9 clutch in the last 12 years but I think TJ at TK Autosports did.  Give him a call at (609) 744-8232 and explain I referred you.  You may get Ian instead of TJ but thats ok - Ian can also potentially answer this question.  Apologize profusely for knowing me.   Say you are coming to the sevens event in 2 weeks time and that you trying to track down a clutch replacement for a T9 box and do they please have the part number and clutch supplier for Jeff's blue Caterham when they replaced it.  I think it was replaced when it had its engine rebuild 2 years back.  I think it is an identical set up to your car.  

 

[S1Steve]

Carl and Mike, I’m not sure what I exchanged with Mike, but this is what I thought may help. My S1 has the standard Zetec flywheel,( wish I installed a lightweight one), a Ford Motorsports clutch and disc. At the time I thought that would work fine with it’s almighty 139.3rear wheel HP and curb weight of little over #1400. I’ll attach information another S1 owner decided to use…. Hope to see you at NJMP.

 

 

[CarlB]

Thank you all for replying. I hope I have a solution on the way. I think I have  a fix if it doesn't, I will make it work. Bruce Beachman is going through the same thing with a customer car. I am reasonably confident the slave cylinder (throw out bearing) was depressing the clutch in the static position. Kit Cat had a old post about getting a clutch from Clutch Masters and they were very helpful. Zetec cars came with a clutch used in the Focus ZX3. This is a 9 inch clutch and the finger height is different than what the stock replacement clutch people are selling now. The current replacement is a 9 1/2 inch clutch. Clutch Masters seemed to know the difference and were easy to work with. I should have the clutch Monday. I now know how much the clutch should push the clutch in and will make the measurements so I am confident the clutch is fully released before I put the car back together. If there is a issue, I learned a long time ago you can't work on a car without a lathe, a mill, a mig welder, and a tig welder.  That aluminum plate the slave cylinder mounts to will get changed so the slave cylinder works. I want to thank Kit Cat and  Vovchandr for there help. I have spoken to a number of people about this and will post a lot of information about this once I am confident of the solution. Bruce Beachman is a really good resource. He is trying to come up with the elegant solution. I want to get to NJMP. He is trying to find the parts used in the original design, so there isn't any need to make custom parts. 

My car is a very early if not the first Zetec car built. The car Bruce is working on is one that came with the SVT engine. The car Bruce is working on is original and it has the same Fidanza flywheel my car has. The SVT cars did not use the larger clutches the SVT Focus used.   

[yellowss7]

Good luck to you Carl.   Jay I’m sorry to hear of your misfortune. And Vlad. I don’t even know what say about your travails.   
 

But you guys are all scaring the crap out of me since I signed up for a track day this Friday.   I’m going to be babying the car and going even  slower than I usually go, hoping to keep the car together.   

 

Hope to see you on track soon.  Fingers crossed.   Tom. 

[Croc]

 

@S1Steve Thanks Steve - that is exactly the piece of paper I was remembering. 

[Black Hole]

22 hours ago, yellowss7 said:

Jay I’m sorry to hear of your misfortune.

Thanks. I have not given up yet. But my time is limited and I need to make the engine run and more importantly make sure the throttle does not stick!

[parsonsj]

On 9/8/2021 at 5:34 PM, CarlB said:

Thank you all for replying. I hope I have a solution on the way. I think I have  a fix if it doesn't, I will make it work. Bruce Beachman is going through the same thing with a customer car. I am reasonably confident the slave cylinder (throw out bearing) was depressing the clutch in the static position. Kit Cat had a old post about getting a clutch from Clutch Masters and they were very helpful. Zetec cars came with a clutch used in the Focus ZX3. This is a 9 inch clutch and the finger height is different than what the stock replacement clutch people are selling now. The current replacement is a 9 1/2 inch clutch. Clutch Masters seemed to know the difference and were easy to work with. I should have the clutch Monday. I now know how much the clutch should push the clutch in and will make the measurements so I am confident the clutch is fully released before I put the car back together. If there is a issue, I learned a long time ago you can't work on a car without a lathe, a mill, a mig welder, and a tig welder.  That aluminum plate the slave cylinder mounts to will get changed so the slave cylinder works. I want to thank Kit Cat and  Vovchandr for there help. I have spoken to a number of people about this and will post a lot of information about this once I am confident of the solution. Bruce Beachman is a really good resource. He is trying to come up with the elegant solution. I want to get to NJMP. He is trying to find the parts used in the original design, so there isn't any need to make custom parts. 

My car is a very early if not the first Zetec car built. The car Bruce is working on is one that came with the SVT engine. The car Bruce is working on is original and it has the same Fidanza flywheel my car has. The SVT cars did not use the larger clutches the SVT Focus used.   

@CarlB, have you solved this issue? I have the EXACT same problem, and am contemplating the of a lathe (to turn down the release bearing carrier on the gearbox) and a mill (to allow the aluminum plate to move about 6mm deeper). If there is a bolt-in solution, I'd be thrilled. 

[MV8]

My two cent contribution:

They probably still sell the tools to check these things but no need to get fancy. I would lay a straight edge like a ruler or carpenter level across the bell with a helper to hold it in place or a spring clamp. I would take dowel or ruler in one hand across the straight edge with the end against the hrb (hydraulic release bearing), then push the hrb to compress the spring in the green bellows as far as it will go, keeping the dowel against the hrb and my finger nail where the dowel and straight edge meet on the front of the straight edge. Mark the dowel then measure the length plus the straight edge thickness. This is the maximum pressure plate (pp) finger distance from the block to bell mating surface (may include a shim plate if you have one). This measurement should be greater than the actual finger height with a new clutch because as the clutch wears, the finger height increases. If it can't move away, the pp will eventually cause the clutch to slip. How much extra space is required depends on the pp finger ratio and the clutch design. Typical pp ratio is 3.5:1 and a clutch is typically worn out after .030" of wear, so add .120" to the max finger height to prevent slipping before it is worn out.

Place a straight edge across the pp fingers and measure to the block to bell mating surface on each side to take the average distance or use spacers on the block to bring the straight edge just above the fingers and measure down to them. Fingers can be slightly bent and uneven. If it is a larger/smaller number, machine/shim the hrb adapter plate. The shim must fully support the entire base of the hrb and would be clamped by the hrb.

I believe the high finger pp applications started around 2002.

[parsonsj]

@MV8 Thanks very much. I've done exactly as you described, and I have a -6mm problem +/- 1mm. It's not as simple as just machining the bellhousing or the HRB adapter plate. The HRB rides on the gearbox input shaft housing, which has a shoulder, so that will need to be turned to allow the HRB to slide farther back. I've got the tools to make these sorts of modifications, but I wanted to talk with some experts in case there's a simpler solution. 

Edited May 27, 2022 by parsonsj

[CarlB]

The clutch I installed last year is fine. It is the pressure plate used in 2 L applications. That is not what Caterham used. They had a smaller diameter clutch. I didn’t have to do anything to the throw out bearing. Everything worked. I do not know if the clutch master people made the fingers sit lower or not. I did not have a stock clutch to compare. The only thing I do not like is the clutch disengages at the top of the peddle. That could be fixed with a smaller master cylinder. I would get in contact with Bruce Beachman. I know he was trying to get the correct clutches from the UK.

[parsonsj]

@CarlBThanks Carl. I've left a message for Bruce. 

[MV8]

1 hour ago, parsonsj said:

@MV8 Thanks very much. I've done exactly as you described, and I have a -6mm problem +/- 1mm. It's not as simple as just machining the bellhousing or the HRB adapter plate. The HRB rides on the gearbox input shaft housing, which has a shoulder, so that will need to be turned to allow the HRB to slide farther back. I've got the tools to make these sorts of modifications, but I wanted to talk with some experts in case there's a simpler solution. 

The input shaft spline engagement and pilot may tolerate a 5mm block shim. I assume these come with a plate that fits between the block and bell that is installed before the flywheel on the block. I've not seen any domestic that did not have such a plate. I believe the thickness is typically about 3mm and affects starter pinion clearance on bell mounted starters versus block mounted. A thinner flywheel may also be an option or some combination. How is your crank end play?

[parsonsj]

@MV8Crank end play should be perfect. This is a brand new Dunnell engine, with about 10 minutes run time on it.     The flywheel and clutch are also Dunnell provided parts.  You're right about the plate -- it was there on the old engine, but Dunnell did not provide one with the new one.

 

In the meantime, I've gone ahead and turned the gearbox input shaft cover to allow the HRB to move back 7mm. Tomorrow, I'll set the bell up in the mill and lower the HRB adapter landings. I'll take some "perfect" measurements to make sure I cut just the right amount. I hope.

[MV8]

Hooray!

Since the full travel without damage on these oem hrbs is usually only about 12.2mm, the minimum hrb extended height/length is important to ensure full release with a new clutch and a given pp.

To check the actual finger position necessary for full release, tape a lot of .030-.040" washers evenly across the pp ring face and install a new clutch.

[parsonsj]

OK, so the HRB height issue is fixed. I had to mill and turn 9mm to achieve the proper clutch depth. All is well now. 

 

Thanks to all for the help!

 

 

 

Edited May 28, 2022 by parsonsj