968 Engine leak down & compression
#1
Rennlist Member
Thread Starter
968 Engine leak down & compression
Finally got to getting the motor under closer inspection. Pulled valve cover, belt covers, pulled plugs, shot couple squirts of marvel mystery oil in cylinders, put some assembly lube on the cams, poured some 30 wt oil all around on everything else and turned motor by hand. Now want to do compression & leak down test. Think a friend of mine has a leak down tool and compression tool.
Want to do leak down and wondered if my smallish PorterCable pancake compressor has enough constant pressure for one of these tools??
Wanted to also confirm my thoughts on compression testing. All plugs pulled during this test? About how long to leave starter engaged on each cylinder?
Water pump is seized and have a little concern with turning over too much as back side of timing belt sliding across seized pump pulley. Dont want to snap the crazy thing and bend some valves. I put a little lube on the backside of the timing belt because of this. At least with the plugs pulled there is not a lot of pressure on the belt??
Thanks John
Want to do leak down and wondered if my smallish PorterCable pancake compressor has enough constant pressure for one of these tools??
Wanted to also confirm my thoughts on compression testing. All plugs pulled during this test? About how long to leave starter engaged on each cylinder?
Water pump is seized and have a little concern with turning over too much as back side of timing belt sliding across seized pump pulley. Dont want to snap the crazy thing and bend some valves. I put a little lube on the backside of the timing belt because of this. At least with the plugs pulled there is not a lot of pressure on the belt??
Thanks John
#2
Rennlist Member
I would strongly recommend not trying to turn the engine with a seized WP. Even though the chances of you doing damage to the valve train during cranking is minimal, it's not worth the risk.
#4
Rennlist Member
Thread Starter
Its all the work that needs to be done to put an old one in just for testing that makes me crazy.
I think I will do just the leak down testing, if things look reasonable then I will invest in the belts/pulleys/water pump and actually start the thing.
Is it difficult to start a 968 engine with just the DME out of the car on a stand??
What tricks would you need to sort out electrically?
John