Hydrolic Clutch - ZR-1 Net Registry Forums

John Boothby · 01-28-2006

What would be the "TYPICAL" life expectancy of the hydraulic clutch system? ie. master and slave cylinder? Mine was last replaced about 2years and 8,000 miles ago. I am having a new master/slave/hose replaced Monday and I want to know how long I can expect it to last in normal city driving? I have a feeling that the last master cylinder was defective. It apparently has been leaking since I bought the car. I had been having to add fluid from time to time especially after a week or so of sitting. Just found the leak on the inside of the firewall. It was seeping behind the insulation and unnoticeable until I pulled the insulation back.

tomtom72 · 01-30-2006

Hi John,

Same place my master leaked and it had between 8K and 9K miles on it. This is a shot in the dark but I figured my car didn't get much use from the original owner, 8200 miles in 15 yrs. I get the car and I must look like a slave driver to the those parts, 8K miles in a yr. The conclusion I draw from my experience is that too little use is no good for the hyd clutch sys. I don't have anything factual or a conclusion drawn from mechanical knowledge though. I'm just guessing. I replaced all the parts and had 8K miles of trouble free driving. I did the adding of the fluid thing from almost the time I got my car till I found the leak inside on the firewall, that was about a month of checking & adding fluid.

I figure the first time I have to add fluid I'm gonna start looking to replace all the stuff again. I still think if the car gets use the seals will remain well lubed and not get stuck from sitting??

Tom

Tom · 01-30-2006

I have seen the clutch master and slave cylinders have bad bores when they come out of the box. You should disassemble any new master or slave cylinder and inspect the bore. The bad bores will have one or more depressions in the surface where there are no hone marks. The bore should have a uniform surface finish from end to end. The cylinders with this bore problem will last for several thousand miles before the seals wear enough to start leaking.

The cylinders are very easy to disassemble, pull the rubber dust boot back, remove the retaining ring and you can then remove the piston assembly. Reassembly is just the reverse.

John Boothby · 02-05-2006

Thanks for all the info. The car is back from the shop and seems to be ok. I drove around town a bit and took a 150 mile trip with no problems. Since the car was repaired at the dealer's, I did not get a chance to look at the cylinder internals. If this problem returns, I will check the next ones.

Thanks for all the info!

01-28-2006	#1
John Boothby Join Date: Jul 2005 Location: Las Vegas, Nevada Posts: 777	Hydrolic Clutch What would be the "TYPICAL" life expectancy of the hydraulic clutch system? ie. master and slave cylinder? Mine was last replaced about 2years and 8,000 miles ago. I am having a new master/slave/hose replaced Monday and I want to know how long I can expect it to last in normal city driving? I have a feeling that the last master cylinder was defective. It apparently has been leaking since I bought the car. I had been having to add fluid from time to time especially after a week or so of sitting. Just found the leak on the inside of the firewall. It was seeping behind the insulation and unnoticeable until I pulled the insulation back. __________________ JB 1990 #148 Red/Saddle Haibeck AYBKG5 Chip/RC Engineering/Flowmasters/K&N/Samco/Fuzzy Dice :cheers:

01-30-2006	#2
tomtom72 Join Date: Dec 2004 Location: Jacksonville, FL USA Posts: 4,645	Re: Hydrolic Clutch Hi John, Same place my master leaked and it had between 8K and 9K miles on it. This is a shot in the dark but I figured my car didn't get much use from the original owner, 8200 miles in 15 yrs. I get the car and I must look like a slave driver to the those parts, 8K miles in a yr. The conclusion I draw from my experience is that too little use is no good for the hyd clutch sys. I don't have anything factual or a conclusion drawn from mechanical knowledge though. I'm just guessing. I replaced all the parts and had 8K miles of trouble free driving. I did the adding of the fluid thing from almost the time I got my car till I found the leak inside on the firewall, that was about a month of checking & adding fluid. I figure the first time I have to add fluid I'm gonna start looking to replace all the stuff again. I still think if the car gets use the seals will remain well lubed and not get stuck from sitting?? Tom __________________ 1990 ZR-1, Black/grey, #2233, stock. ZR-1 Net Reg Founding Member #316 & NCM member

01-30-2006	#3
Tom Join Date: Jan 2004 Location: Southern CA Posts: 108	Re: Hydrolic Clutch I have seen the clutch master and slave cylinders have bad bores when they come out of the box. You should disassemble any new master or slave cylinder and inspect the bore. The bad bores will have one or more depressions in the surface where there are no hone marks. The bore should have a uniform surface finish from end to end. The cylinders with this bore problem will last for several thousand miles before the seals wear enough to start leaking. The cylinders are very easy to disassemble, pull the rubber dust boot back, remove the retaining ring and you can then remove the piston assembly. Reassembly is just the reverse.

02-05-2006	#4
John Boothby Join Date: Jul 2005 Location: Las Vegas, Nevada Posts: 777	Re: Hydrolic Clutch Thanks for all the info. The car is back from the shop and seems to be ok. I drove around town a bit and took a 150 mile trip with no problems. Since the car was repaired at the dealer's, I did not get a chance to look at the cylinder internals. If this problem returns, I will check the next ones. Thanks for all the info! __________________ JB 1990 #148 Red/Saddle Haibeck AYBKG5 Chip/RC Engineering/Flowmasters/K&N/Samco/Fuzzy Dice :cheers: