Different clutch on BDR

letitbe · #1 (**permalink**) 08-09-2005, 05:53 AM

It seems like a lot of BDRs are having clutch problems with the hydralic clutch.
Has anyone tried to convert to the old style mechanical spring loaded type.

Is the clutch with hydraulics having a problem because of heat? There has to be an answer to the problem.

I haven't had this problem yet but I"m trying to prepare for it.

Letitbe

madmaxx · #2 (**permalink**) 08-09-2005, 07:26 AM

I have to beleive it is heat related. I do not have header wrap or coating and let me tell you the master cylinder booster, clutch master cylinder get extremely hot. I am debating header wrap and speed sleeves for the headers.

conan · #3 (**permalink**) 08-09-2005, 08:03 AM

I own BDR #143 have had the car for about a year with 1400 miles on it,havent had a problem with boiling fluid. headers are ceramic coated. It is my understanding that older BDR's dont have ceramic coated headers as standard equiptment. with yours being #202 you should have the coated headers if engine was installed by BDR

JayBar · #4 (**permalink**) 08-09-2005, 09:17 AM

I have ceramic coated headers and I still "cooked" my clutch master cylinder. Once I replaced both the master and slave and wraped the line in a heat reflective tube. That appeared to cure the problem. But while the engine was being replaced I wraped the headers. May be over kill but it is a PITA to loose you clutch while out on the road.

trs900 · #5 (**permalink**) 08-09-2005, 01:36 PM

Speaking of headers and heat it seems that my sidepipes where the 4 tubes go through body of car are starting to loose their coating.. anyone else had this problem.. only 1500 miles on car..

jeffko · #6 (**permalink**) 08-09-2005, 02:26 PM

I believe it to be 2 problems. One is in fact heat and the other is low quality parts. It seems the inherent problems of the poor parts quality is often further compounded by high fluid temps. Hydraulic fluid suffers adverse effects and its ability to maintain viscosity and anti-wear agents degrade. From what I have read this usually starts occurring at approx 180F. Uncoated headers run upwards of 700F so there is plenty of heat transfer available. Without a sufficient air gap that crappy little mazda clutch slave does not stand a chance. Let alone being designed for 4-6 cylinder pressure and being used for high performance V-8 clutch pressures. Bad recipe!

Short term solution: get as much air gap as possible and use some kind of heat shield to deflect temps.

Long term solution: ??? We should all do some research and post to this thread until a viable solution is found.

That’s my two cents.

JayBar · #7 (**permalink**) 08-09-2005, 03:49 PM

Quote:

Originally posted by jeffko

Long term solution: ??? We should all do some research and post to this thread until a viable solution is found.

[/b]

There is a solution see my post above. I got 5K miles on my car.
Mazda salve has served me well. Drag racing, and open track events. Get a Wilwood master cylinder about $50.00. Then wrap the master and line in some type of insulation and reflection tape or tube. The slave is far enough back to have a decent air gap.
For less that $75.00 you have a perminant cure.

jeffko · #8 (**permalink**) 08-09-2005, 04:13 PM

Jaybar, I saw your post. My opinion is that a 4 cylinder mazda clutch slave is not up to the rigors of an 8 cylinder high performance clutch. It is not just a proximity problem with the exhaust. I believe we need a better design that fits the application. There is a noticeable percentage of BDR owners that have fluid leaking problems including myself.

Nor Cal Al · #9 (**permalink**) 08-10-2005, 08:54 AM

I think if you search past threads you will find this all has been discussed before. I went with a kit from Anthem Motors in Phoenix. They have a block that bolts to the engine and uses a pull type piston. I think it is a Wilwood product. Works like crazy, but you will need to find the fitting that mates the european flare from the cars tube to the domestic hose supplied. I could not find it in rural NorCal so I had a hose made with proper ends. No problems at 1700 miles. Also, I had my headers ceramic coated. I have the 392W, King Cobra clutch and a Tremec.

jeffko · #10 (**permalink**) 08-10-2005, 04:38 PM

NorCal Al

I think your solution is a good one, but rather expensive. The price is now roughly $500. I am hoping to come up with a quality solution for half the cost. Still trying though...

DC COBRA · #11 (**permalink**) 08-10-2005, 06:00 PM

I used the adjustable hydraulic throw out bearing from Mcleoud Industries. My whole clutch assembly is from Mcleoud, my headers are ceramic coated, also they have 2'' diameter tubes(custom). I have not had any clutch, clutch master cylinder, or even any brake fluid problems what so ever. The Mcleoud unit works so smooth and nice, same time every time. I now am approaching 2000 miles on the car.

DON

JayBar · #12 (**permalink**) 08-11-2005, 02:44 PM

jeffko

Quote:

Originally posted by jeffko

[Long term solution: ??? We should all do some research and post to this thread until a viable solution is found.

[/b]

Why do you insist on re-inventing the wheel. I gave you a viable solution. It's not rocket science. You can buy the Wilwood master and a rebuilt slave from Napa. Insulate the master and line to the slave. That will cure any problem you have. One step fruther would be to wrap the headers. Now if you like to spend money and fabricate things, you could buy the Wilwood slave, but it is a "puller" and will need a custom bracket.

AS far as the Mcleoud unit I have heard nothing but horror stories about it. Image a leak inside your bell housing, you would wish you had a slave cylinder from a Yugo instead.

DC COBRA · #13 (**permalink**) 08-11-2005, 04:57 PM

Yes I have heard the horror stories also, but I think this one was their newest model. So far no problems, besides you will never see me wishing for a Yugo part on my cobra, I would rather push it and wipe up the leaks. HA!HA!

DON

tfarhood · #14 (**permalink**) 08-11-2005, 05:15 PM

The only reason my slave failed was due to the way I installed the rod that connects the slave piston to the clutch fork. I used a threaded rod with jamb nuts on it. The jamb nuts vibrated around allowing my slave piston to pop-out of the cylinder. The slave never leaked at all. when I replaced it, I found the mirror image slave so the bleeder valve points up. 6200 miles and thousands of shifts, no leaks ever from the slave. The master formed a dripping leak at the seals on the plunger on the inside of the cockpit after about 5000 miles, the new master (identical unit) is working fine. I do have header wrap on my headers, but no other heat protection. I have never had any clutch or brake fluid failure due to heat or any other reason. This is not a difficult system. Header wrap or ceramic coating is a good idea regardless of the clutch or brake systems. Less heat under the hood is always a good thing.

Snakester · #15 (**permalink**) 05-14-2006, 03:19 PM

The slave cylinder was leaking so bad (only 300 miles on car) when I changed cylinders I noticed the fluid was very thin , very black making me think there was a heat related problem! I made and installed a heat shield and haven't had any other problems.

Snakester

tamanaco · #16 (**permalink**) 09-09-2006, 11:18 AM

Quote:

Originally Posted by tfarhood

The only reason my slave failed was due to the way I installed the rod that connects the slave piston to the clutch fork. I used a threaded rod with jamb nuts on it. The jamb nuts vibrated around allowing my slave piston to pop-out of the cylinder. The slave never leaked at all. when I replaced it, I found the mirror image slave so the bleeder valve points up. 6200 miles and thousands of shifts, no leaks ever from the slave. The master formed a dripping leak at the seals on the plunger on the inside of the cockpit after about 5000 miles, the new master (identical unit) is working fine. I do have header wrap on my headers, but no other heat protection. I have never had any clutch or brake fluid failure due to heat or any other reason. This is not a difficult system. Header wrap or ceramic coating is a good idea regardless of the clutch or brake systems. Less heat under the hood is always a good thing.

tfarhood, can you tell me where to find the mirror slave cylinder? Thanks

Gatorac · #17 (**permalink**) 09-09-2006, 02:14 PM

You must keep the fluid in the clutch system fresh. The slave and master will not last long if you don't. It won't matter if the slave is from a Yugo or a Ferrari.

I have found I need to replace the fluid twice a year. Suck the old fluid out of the master and refill it with new fluid. When bleeding, you can get 3 pumps of the pedal before you need to fill the master back up. Don't try 4. I have to bleed almost a full 12 oz bottle of fluid through it before it starts to look clear.

I also have some insulated sleeving over the hard line from the master to the slave.