I've searched, but cannot find a thread that I thought had some details on an upgrade from the factory F40 Clutch? Anyone have a source? Thanks very much, Mark
Mark, There is a guy down the street from my house who says he has lots of spare F40 clutches. He goes by mrknowitallf40 on here. You should send him a PM. http://www.ferrarichat.com/forum/member.php?u=16787
The ap clutch is really pretty good. Are you sure its not the bellhousing/hydraulic system? Many guys think it the clutch when its just a leaking bellhousing. You can burn up the clutch pretty fast if the the system is leaking. Nobody ever changes the clutch fluid and the reservoir is vented to atmosphere. Griling makes a bellows that fits in the cap to stop this. All of the f40's and 288's eventually need new bellhousings. I switched to silicone fluid to avoid this. I know it makes bad brake fluid but it works great in the clutch. Stops the corrosion problem pretty quickly. Look in your clutch reservoir to see if there is magnesium mud in it. What type of an upgrade do you want?
AP makes a glycol based fluid that was specifically formulated for magnesium compatibility. I have been using it for years in 288+F40 with no outgassing of the mag which is what causes 95% of the hydraulic problems in those. I have never had a bell housing sealed and have had zero problems. That fix was dreamed up by the factory because their fluid caused so much gassing in the mag.
Brian, I noticed Ferrari of Atlanta flushed and changed the clutch fluid on my F40 to silicone based DOT 5 brake fluid for the magnesium gassing issue last service. I assume the silicone fluid is better than DOT 4 brake fluid but that the AP glycol based material is the best solution? Regards, Drew Altemara
Its the water in the fluid that causes the problem glycol or not. The outgassing is hydrogen gas that is produced by the corrosion reaction between the bellhousing and the steel fittings that are screwed into it. That bellhousing will corrode and you cannot stop it ,only slow it down. I am on my original bellhousing and I have changed to stainless steel fittings which are less electrochemically active. Silicone brake fluid does not absorb water and the new fluid is much better than it used to be. What AP fluid are you refering to? Most magnesium castings from the era were pretty porous and ceramic sealing the hydraulic conduit is not a bad idea. A sleeve would even be better. Being compatible with magnesium only means that it is PH adjusted to prevent corrosion on magnesium. Once the fluid is wet it will still cause a problem.
In my opinion it is. Very few even know of the AP fluid because they don't promote it. I only found out about it because I wrote an article about brake fluid a number of years ago and discovered it doing research. Been using it ever since. F40 uses seperate reserviors so you can use 2 different fluids but 288 does not. I abhor the idea of silicon fluid in a brake system so this is a good choice.
Silicone brake fluid is the only fluid that wont mix with water or absorb water. It also has a neutral PH. Its come a long way since the 70 when everyone in the SCCA used it because of its elevated boiling point. Problem was that its compressible at high temperatures and used to give the feeling of a spongy pedal. Better than no pedal. Some have reported seal compatibility issues but that was a seal material problem. Fact is that every brake system in the military from tanks to aircraft uses the stuff and it lasts forever and it completely noncorrosive. All the motorcycle manufacturers use it as well. Its come a long way since GE made it. Repairing the clutch release bearing on an F40 is a big job. Problem for us is that the factory does not retroactively fix issues. I do have spare bellhousings but thats just so i dont have to refinish them! In the clutch it really no issue. What do you feel is the downside?
Does this mean that we will never know the identity of the afore mentioned fluid? What did you use before you did research for your article?
Ap racing does not make a fluid specifically for clutches. They make only brake fluid. Any of their products can be used in the clutch system. AP 551 is recommended. AP 600 is specifically warned not to be used in conjunction with magnesium due to its corrosive nature and nonneutral ph. Mystery solved. Just dont use AP 600 in the clutch. Fine for the brakes. Thanks Brian you almost got it right. All the AP fluids are glycol based as are most others. The big exception being Castrol SRF.
Hi, can you private message me? I would like to learn more about having a bellhousing repaired, as I feel I have one that is starting to exhibit signs of the dreaded internal corrosion. Thank You! Jordan