Hot starting problem
#16
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Bill: Your test is valid, but when you're dealing with 25 year old fuel hose it's not always a good idea to disturb them by clamping. If the hose becomes fractured it's a very difficult section to replace, and where Russell lives he may not be able to find adequate supplies. However, the check valve discussion is also a good point. My shop used to replace them from time-to-time, but I had found them becoming hard to get. Quite honestly, I'd assumed that they were NLA by now. If you have a good source that's available to Russell you might want to post it, along with a part number. Cheers!
Pete
Pete
#17
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Pete,
You are correct, the CV is NLA.
There are 3 fixes that I'm aware of. First is to replace the fuel pump with new (I'm assuming there will be a new check valve in the pump). Second, and this is the direction I took, is to replace the banjo fitting on the end of the fuel line at the fuel pump with a banjo fitting that contains an integrated check valve. Zims Autochenik in Bedford TX carries this part. The third method is as I mentioned earlier, is to add an inline check valve. I don't know the specifics of this part, but John Walker in Seattle mentioned it to me.
Listers, best of luck in your repair.
Mark
You are correct, the CV is NLA.
There are 3 fixes that I'm aware of. First is to replace the fuel pump with new (I'm assuming there will be a new check valve in the pump). Second, and this is the direction I took, is to replace the banjo fitting on the end of the fuel line at the fuel pump with a banjo fitting that contains an integrated check valve. Zims Autochenik in Bedford TX carries this part. The third method is as I mentioned earlier, is to add an inline check valve. I don't know the specifics of this part, but John Walker in Seattle mentioned it to me.
Listers, best of luck in your repair.
Mark
#18
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Fascinating, I suspect the check valve is faulty in my 911SC too as the fuel pressure is low after an over night stop but fine during the day when I go from place to place and don't leave it for too long. After a long stop it doesn't burst into life like it used to it just rumbles into life as fuel pressure builds up, runs fine apart from that. If anyone knows a source for in - line check valves let us know , sounds like there will be a few takers.
#19
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You are correct, the CV is NLA.
#20
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Bill: Great info - thanks for the effort!
bones: Sorry, an overnight stay means that the car is cold enough for the cold start system to kick in, which, if working correctly, will allow the car to burst to life. You should have your fuel mixture checked, as well as an inspection for possible air leaks and other basic issues. Maybe it's tune-up time...
Pete
bones: Sorry, an overnight stay means that the car is cold enough for the cold start system to kick in, which, if working correctly, will allow the car to burst to life. You should have your fuel mixture checked, as well as an inspection for possible air leaks and other basic issues. Maybe it's tune-up time...
Pete
#22
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Mark: No big deal - parts occasionally go out of favor with Porsche, then they realize there is still a demand and put more into the system. I dealt with a couple of the largest dealers in the U.S. on a regular basis, both in SoCal, and there were times when neither place had pieces that I needed to fix something. It happens!
Pete
Pete
#23
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I found the fuel pump attached to the crossmeber behind and below the tank with a hose clamp, I am sure that this is not the orginal fitment method. The fuel pump is newish looking and is encased in a rubber housing insulating it from the earth. The banjo clip (pressure side) looks "wet" and the guard plate below the fuel pump has some fuel leak residue on it, indicating that the banjo clip is leaking from it seals. I am not convinced that the leak is big enough to cause my problem, so I would like to get a check valve.
To simulate the check valve I clamped the pipe between the tank and the fuel pump (most flexible rubber hose on the fuel system so it was the least likely to be damaged by clamping) after running the car, I left it for 30 minutes and the car started first turn (looked like the problme solved). I repeated the test later in the day and was back to the old problem, so I will test it again-2 out of 3 rule.
My immediate problem is that Porsche parts are harder to find in Zimbabwe that democracy, I am told that the check valve from a Mercedes 230E would probably do the trick, is there anything special about a Porsche check valve?
Because of a dirty fuel problem a second fuel filter was installed after the fuel pump, I would install the check valve after this filter.
The accumulator looks newish, much shinier than other parts in the engine so I do not immediatley suspect it.
Thanks
Russell
To simulate the check valve I clamped the pipe between the tank and the fuel pump (most flexible rubber hose on the fuel system so it was the least likely to be damaged by clamping) after running the car, I left it for 30 minutes and the car started first turn (looked like the problme solved). I repeated the test later in the day and was back to the old problem, so I will test it again-2 out of 3 rule.
My immediate problem is that Porsche parts are harder to find in Zimbabwe that democracy, I am told that the check valve from a Mercedes 230E would probably do the trick, is there anything special about a Porsche check valve?
Because of a dirty fuel problem a second fuel filter was installed after the fuel pump, I would install the check valve after this filter.
The accumulator looks newish, much shinier than other parts in the engine so I do not immediatley suspect it.
Thanks
Russell