Don Carter

Made it to el Paso, no problem. Cleaned the FP fuse this morning that had a dull gray surface in the contacts. Will keep going to phoenix.

Don Carter

Mrmerlin

thats a corroded ground it needs to see some deoxit and a wire brush.
Glad your ride is going well, It should continue that way!

karl ruiter

Looks more like build up from a slight fuel leak than corrosion to me. Still could have been the issue. When you get where your going a new pump might be prudent. I would also have a very detailed look at that ground wire.

Mrmerlin

I thought the boot was a "filled with water situation" since the check valve looks to be clean of deposits

Alan

Don made it to Phoenix (well Mesa anyway) in time for dinner before the show!

Timing was tight but we made it work. There was another cut-out problem on the way in that caused a small extra delay. Seems to definitely be the fuel pump. Dan at Exotic Motorwerks may be able to help out tomorrow - he has a pump ready to go! I know Don was trying to get one shipped by Roger also.

One way or another the trip should continue!

Alan

James Bailey

Awesome guys, keep them running !!

Don Carter

Wow, what a day. The car ran perfect for about 8 hours just like yesterday, then about 50 mile out of Mesa, it died. We had noticed that when it rests for a while it starts back up so we let it sit for 10 min then fired it up and the pump was buzzing normally. I got some good video of the sound it was making when it was running bad that I will post later. Anyway, got back on the road and made it to Mesa and had a fun dinner with Alan, Dan and Rick followed by an incredible concert (Steven Wilson). I'll check on the local pump tomorrow (thanks Alan, and thanks Dan for making the dinner so special for my son. You had him laughing so hard he almost lost his dinner)

dr bob

Don (and others playing along...), does your 86.5 have the in-tank fuel pump? Looking for the extra wiring that connects to the main pump with a second connection to an in-tank pump.

Hot-climate operation caused Porsche to add the fuel cooler to the cars tio help avoid boiling the fuel in extended hot-weather operation. Still experiencing problems even with the fuel cooler, they added the second in-tank pump to prime the main pump when fuel temps go too high. The pressure drop through the in-tank strainer and the suction fitting and hose is enough to cause the fuel to boil as it enters the main pump. Putting the priming pump in the tank ensures that there will be liquid at the main pump inlet. In process terms, this is callled "net pump suction head", the amount of inlet pressure needed to avoid boiling in the first stage of a pump. When the fuel boils, the pump makes a much different sound as it tries to pump vapor instead of liquid. Regardless of whether you have an in-tank pump that's failing, a suction strainer that's partially clogged, or just plain "fuel is too hot", the net symptom is the same.

To minimize NPSH issues, perhaps the easiest thing to do is to not let the fuel tank run low. Perhaps you can see a connection between your fuel pump issues and running below a certain level in the tank? Stopping and letting the fuel cool off for a bit wil also help. Turning off the AC is a wash really, since the fuel cooler doesn't do anything with AC off. Maybe reducing the fan speed will extract more heat from the fuel.

Don Carter

Bob,

You may be on to something with your theory. The pattern of failure, then cooling off fixing the issue seems to fit. We never let the tank run low though, it was almost full when it first failed. We had driven about an hour after full, so maybe 4-5 gallons used from the tank. I'm headed to Dan Warner's shop in a few minutes to have the pump and filter replaced. He said he also replaces the strainer in the tank when he does a pump, so if it is partially clogged, that may help. The pump is original, so I don't feel bad about replacing it. Car has about 105k miles on it. We have run the very cold R12 AC the entire trip. I'll discuss your theory with Dan as well.

Keith Coe

Don: sorry to hear about all your issues with the trip. Glad to hear that you're getting the problem narrowed down. If the trip had been flawless, it probably wouldn't be as memorable in years ahead. Good luck on the return trip to Cypress!

Don Carter

Also, no in tank pump on 86s.

Dan listened to the video and immediately said it was the bearings in the pump. He drove us to a nearby mall and will have it done in about 2 hours. There were no less than 7 928s at his shop so I think it's in good hands.

Don Carter

Keith,

Your right, this will be a more memorable trip with all the car issues. We met people and stayed in places we would have never seen otherwise.

Darien

Don, glad you're safe. Good thread on faulty FP indicators

redpathtribe

Don, it is absolutely in good hands. Dan knows 928's like few others and is great to work with. One of the very few people I trust implicitly to work on my car.

Great meeting you and Josh last night. You should be all set after Dan gets finished working on your car. Enjoy the rest of your trip!