CIS No Start

outlaw912 · 05-21-2011, 07:30 PM

I have a 71 911T with CIS. Dont ask...

Today there was a very high pitched sound from the fuel lines when I turned the key, then the car cranked, and cranked, and cranked. No start. I haven't started the car in two months but before this I've never had a problem. I tried it a couple more times and then the battery died. And I noticed some fuel around the accumulator aswell. I tightened the hoses at the filter and accumulator but no still luck. I pulled one of the injectors and its spraying normally. Now after a charge, I hear the starter click but no crank. There is fuel leaking from where my headers meet the muffler. Is it possible one of the cylinders is full of fuel? I'm tempted to pull the spark plugs, but any advise would be much appreciated.

I hope I didn't fry the starter.

Thanks in advance

j911brick · 05-21-2011, 09:56 PM

I can't believe nobody wants to throw this guy a bone...

I'll take a stab at it. That high pitched noise was probably the injector(s) bleeding out. May a leaking injector or stuck fuel distributor piston. Yes, it is possible to fill the cylinders with fuel. Its called hydro-lock and if it happens you may not be able to crank the car. Disconnect the ignition and pull the plugs. turn the motor over by hand to at least two revolutions to displace as much fuel as possible. Do not crank the motor with the starter if you have any fuel under the car (the vapors with ignite once you hit the starter). Keep in mind this whole process is pretty much a fire waiting to happen and you should probably have a fire extinguisher handy. Once your convinced you have the fuel out you can put the plugs back in and start the car. Now you can start to fix the problem you had in the first place. Once you got everything sorted out change the oil because its probably got allot of fuel in it now.

don gilbert · don gilbert's Garage

I agree with James, sounds like the metering piston was stuck open and you flooded the engine. Hydro locking can do major damage to your engine if you not careful. even just by cranking the starter you can bend a rod into a noodle, split a piston into, or pull all your head studs. (seen all three) Be sure and check to make sure you oil is not diluted with fuel once you get it running, when the metering piston is sticky, cis dumps ALOT of fuel onto the tops of you pistons. report back with your finding.

outlaw912 · 05-22-2011, 07:24 PM

OK,
So I removed the plugs. 5 of the them were severly corroded. Two of them were wet with fuel. I hand cranked the motor 5 or 6 times and quite a bit of fuel was leaking from the header studs and muffler. I releived the fuel pressure and removed the fuel distributor and air sensor plate from the airbox. When I disassembled it I found the plunger was infact stuck. I removed it with a pair of needle nose pliers. I cleaned the whole thing with carb cleaner and reassembled it.

When will I know if its safe to put in new spark plugs? Also what is the best way to reestabish the fuel pressure so I dont flood the motor again when I try and start it? Also, do I need to worry about which fuel lines connect to which ports on the fuel distributor? I marked it but the gasoline washed my sharpie marks off

Thanks so much. Hopefully this works.

j911brick · 05-22-2011, 09:38 PM

It doesn't matter where the lines go on fuel dist. They all spray at the same time and the same amount. Just make sure the center one goes to the WUR. If everything is dry you can put it back together. No need to prime the system. Should only take a couple seconds to get fuel running through the system again.

outlaw912 · 06-10-2011, 07:28 PM

ok, as I was reassembling the fuel distributor last weekend I over tightened one of the banjo fittings and broke it in half. I tried to order one from pelican but found out they are no longer available from porsche. I think they are 5mm fittings. Anyone know the exact size and where I could find the right part? Also should I torque them to a specific setting to avoid breaking them? Any help is greatly appreciated.

89turbocabmike · 06-10-2011, 08:51 PM

Place a want ad with picture in the used parts classifieds or try BAT Inc or Special T Auto. I know that BAT had them.

spuggy · 11:39 AM

Quote:

Originally Posted by outlaw912

ok, as I was reassembling the fuel distributor last weekend I over tightened one of the banjo fittings and broke it in half. I tried to order one from pelican but found out they are no longer available from porsche.

Did you type "CIS banjo" into Google? Remember that many years of VW, BMW, Mercedes, Ferrari, Cadillac and other cars used Bosch CIS as well.

Len in this thread is a Pelican, and obviously supplies/stocks CIS parts as well as makes fuel lines up: 930 Fuel Hose Assys

Or try these guys - not dealt with them myself yet, but found them when I was figuring out how to modify my fuelling - they list lots of useful things for CIS: CIS LINE & FITTINGS