Clutch to Valve Guides - the slippery slope
01-15-2013, 02:43 PM
#16
Instructor
Thread Starter
A very tardy update (for those interested)
It is possible to replace the bronze exhaust valve guides yourself, but (having now done it) I can not recommend it to any but the most hardcore do-it-entirely-yourself-er. If anyone is interested, I can share the details and lessons learned. For those curious as to the ending: the guides are all installed to exactly 13.2mm height and reamed to 9mm clearance; valves lapped and good to go.
Lessons learned:
1) The perfect tool for removing the circlips (from the pistons) is a corkscrew. Little screwdrivers, patience, needle nose pliers, ... do not work. A corkscrew removes then in seconds and leave no marks on the pistons.
2) The Porsche tool 9500 (000.721.950.00) to install the circlips is USELESS! The little "bridge" next to the cutout snapped off when installing the first circlip. Needless to say, one finds this out when the cylinder o-ring is coated in loctite 574 and when the tool fails, you are seemingly doomed. Sincere thanks to Rocket Rob for allowing me to borrow his Stomski circlip tool which worked like a charm.
3) Timing the engine appears to be scary, and they are few places I have found which present the needed information in a clear and concise manner. I will attempt in the next post (give me a day) to write up what I have found to be useful - or at least the infomration that made it clear how all this works and what to look for.
4) It is very difficult to remove a broken exhaust stud. I did not buy a special tool for this, and a dremel with diamond and carbide grinders is a marginal (and very slow) substitute.
5) Finally - there are any number of posts and threads on the perfect lubricant for the case, gaskets, o-rings, ..... I have decided to use only what is specified in the service guides - optimoly, loctite 574, or light coat of oil. If it leaks, my fault for not following the myriad advice.
Cheers,
Scott
It is possible to replace the bronze exhaust valve guides yourself, but (having now done it) I can not recommend it to any but the most hardcore do-it-entirely-yourself-er. If anyone is interested, I can share the details and lessons learned. For those curious as to the ending: the guides are all installed to exactly 13.2mm height and reamed to 9mm clearance; valves lapped and good to go.
Lessons learned:
1) The perfect tool for removing the circlips (from the pistons) is a corkscrew. Little screwdrivers, patience, needle nose pliers, ... do not work. A corkscrew removes then in seconds and leave no marks on the pistons.
2) The Porsche tool 9500 (000.721.950.00) to install the circlips is USELESS! The little "bridge" next to the cutout snapped off when installing the first circlip. Needless to say, one finds this out when the cylinder o-ring is coated in loctite 574 and when the tool fails, you are seemingly doomed. Sincere thanks to Rocket Rob for allowing me to borrow his Stomski circlip tool which worked like a charm.
3) Timing the engine appears to be scary, and they are few places I have found which present the needed information in a clear and concise manner. I will attempt in the next post (give me a day) to write up what I have found to be useful - or at least the infomration that made it clear how all this works and what to look for.
4) It is very difficult to remove a broken exhaust stud. I did not buy a special tool for this, and a dremel with diamond and carbide grinders is a marginal (and very slow) substitute.
5) Finally - there are any number of posts and threads on the perfect lubricant for the case, gaskets, o-rings, ..... I have decided to use only what is specified in the service guides - optimoly, loctite 574, or light coat of oil. If it leaks, my fault for not following the myriad advice.
Cheers,
Scott
