Has anyone had success cleaning a EFI in tank fuel pump before. The prowler has a hard start problem and is not keeping fuel pressure when I apply the first turn of the key. A few priming key flicks and it runs great. But it has died out at a light not being able to keep up pressure.
No cels yet and it's more inconvenient then catastrophic. I have pulled motorcycle pumps that were jammed up and sonicated them to get all the crap out but never a car fuel pump.
part is NLA except on the cater market as a 400$ partial part that requires moving tons of old plastic over the new pump which I would prefer to avoid if possible.
Any other ideas.
It's more likely the pump sized from moisture than the fuel. Thats what happened on my Miata. It's possible that the actual pump could be a simple replacement- even if the assembly is nla
That's the one. It requires moving a ton of old nla plastic parts from the original car over and big chance to break something I cannot replace and would have to fab from scratch.
it's not a money thing it's a risk thing.
In reply to wearymicrobe :
I cannot find pictures of the actual pump. It looks like the plastic has tabs to keep them together. Is that the problem with them breaking? It just hit me, wonder if a housing could be 3d printed to hold an aftermarket pump. I couldn't find instructions for the above kit. Do you have a link?
How difficult is the pump to remove?
If its easy to get access to the pump, then it might be worth trying to replace the pressure regulator before trying to disassemble the pump.
A sticking regulator could cause the issues you are seeing if it's sticking and not maintaining pressure. I'd assume a pump would work, or not work, but a regulator could allow fuel to drain back creating the need to cycle the key to build pressure on a cold start.
Mr_Asa
MegaDork
7/4/24 11:22 p.m.
Stampie said:
In reply to wearymicrobe :
I cannot find pictures of the actual pump. It looks like the plastic has tabs to keep them together. Is that the problem with them breaking? It just hit me, wonder if a housing could be 3d printed to hold an aftermarket pump. I couldn't find instructions for the above kit. Do you have a link?
This is a very possible thing. You would be looking at nylon or some other hydrocarbon resistant filament, and those can take more effort to print than the average home printer. (Provided that 300°C is still a little high for your average home printer.)
Mr_Asa said:
Stampie said:
In reply to wearymicrobe :
I cannot find pictures of the actual pump. It looks like the plastic has tabs to keep them together. Is that the problem with them breaking? It just hit me, wonder if a housing could be 3d printed to hold an aftermarket pump. I couldn't find instructions for the above kit. Do you have a link?
This is a very possible thing. You would be looking at nylon or some other hydrocarbon resistant filament, and those can take more effort to print than the average home printer. (Provided that 300°C is still a little high for your average home printer.)
I have a 3D printer with a annealing chamber so printing in nylon or carbon is not an issue. Would only take a few hours in solidworks if I really had to remake the parts plus printing time. I am going to pull the pump tomorrow afternoon and take a quick look at just how much trouble I am going to be in. Pump only has 25K miles on it but its been sitting. I have had luck in the past letting them soak in 100% seafoam then sonicating it which is my first pass option I think. I bet that its a 3.5 300m pump that they are reselling but until I get in there and remind myself what it looks like and the condition. Part of me thinks its just gummed up from sitting and with a thousand miles of use and a lot of cleaner in the tank that it will come back to life. I think it's actually the check valve that is failing not the pump itself which is why I am not keeping pressure up.
Just working through it in my head with you guys helps.
Is the fuel tank plastic or metal? Is sticking a bulkhead fitting or welding a threaded bung to it and running an external pump an option?
Could you install an inline check valve on the supply side?
Pump was pulled and is making really bad noises when powered externally. I checked pressure and its all over the place. Cleaned it up and it runs better but still has pressure fluctuations and flow is uneven. So sent the cash for the full assembly to the prowler store along with another 400$ or so part on top that I need to make the car perfect.
I am going to find a better power supply and run cleaner through this pump for 4-5 hours or so in the sonicator like I do with the Harley pumps and see if I can get it back. But need to get a bigger sonicator from a friend to try that and a LOT of cleaner so might get put on the back burner. Wife and family will be borrowing the car and don't want any trouble with them out having fun.
All done and it no longer stalls at a light. The pump delivered looks like a Walbro 255 GSS series fitted into a housing that was shared with another car. Which is nice because if I had to I am 90% certain I could make it myself if they stopped being available. Had to cut the pump cap off and replace it with another part that was luckily available and easy to find.
Not 100% sure it was the pump itself but I put in a new pressure regulator, new pump, filter and if it starts first thing tomorrow in the morning then I will consider it fixed. Pump is much quieter though and that could just be that it is new or a different part. The OEM part was a Walbro as well but it is 25+ years old and the sock is much smaller then what I had.
In reply to wearymicrobe :
Could you share any pictures you have of the disassembled pump? I had a hard time finding them on the web.
Give me to tonight. I left the old unit off the car.
