Factory Part # 42021 TA030 Electric Fuel Pump for 1991 KS4 c/w SC EMPI system Note: Might fit other years/ models that use EMPI system
Fuel Delevery Requirements Does anyone happen to know the pressure or flow requirements that an aftermarket fuel pump for a 1991 SC Sambar will need to have? Does the pump have a built in pressure regulator or does the truck have a seperate one? Also is there some sort of valve inside the tank that must open when the pump is running to allow fuel to be pulled out? I have 5 gallons of fuel in my tank. Prior to filling with the 5 gallons, I inavaertenly left a hose off after removing the tank and cleaning it and no fuel poured out as I expected it should be after I discovered that I had left the hose off (or while I was trying to dump out the old gas). Does the pump make a whining noise when the key is turned on? Mine doesn't make any noise and even after I reattached the pump inlet hose and disconnected the outlet hose from the filter to see it pump fuel, I had nothing but a clicking sound coming from the pump itself that I could really only feel more than I could hear (only one click). I have only had the truck 3 days so I am not framiliar with all of the normal sounds. Context clues lead me to believe that this pump is bad (it just went bad overnight, no warning) and I have found several aftermarket pumps that may work (I did see the post from Timetripper that said which pump he used (Jideco E8059) and it is ~$260 where I live), the thing is that I belive there are much cheaper pumps that will do the trick if I just knew the fuel delivery requirements. The Advanced Auto Parts website said that the pump only produces 1-5 psi but I am sure with EFI that this needs to be much more. Please answer all that you can... I promise to do the same as I learn more. I hope to create some sort of spreadsheet with all of the parts that can be used and locally purchased (even those requiring modification).
Before spending money on a pump, why not verify that you have 12V power to the pump with a multimeter or test light? I'm just cheap!
Fuel Pump I have removed the pump, cut the factory plug off so I can use it on a new pump, and connected it straight to the battery...still no luck.
Well, that sounds like the pump to me then. You'll need to know the pressure for the system to replace the pump, or use a pressure regulator then. I don't know that one though, sorry!
The low psi pump wont work... Its for carbs. You need somewhere in the neiborhood of 30-50 psi. Usually there is a vacuum controlled regulator built into the fuel rail. I cant speak for the subaru's regulator though.
Will the psi differ with supercharged trucks? Or is 30-50 psi standard? Thanks for the replies thus far...
MWYANT It sounds to me that your fuel pump is siezed, you also mentioned that you cleaned out your fuel tank. Is it possible that something got sucked into the fuel pump and is not letting it spin? Can you look into the intake tube of the pump with a flashlight to see if there is a foreign object in there. Or spray some carb cleaner into it and let it sit for a while, maybe that would soften up whatever is jammed in the impeller. Just an idea that might save you $300.00. Also I looked up the Fuel Pump output pressure and it should be 3.1kg/cm2 or 44.09 PSI hope this helps!!
Sorry didn't read all of your questions. The fuel pump pressure according to my book is the same for S/C or regular EMPi systems. And there is a pressure regulator that regulates to 3.1kg/cm2. It is interesting that in the book it also states that the pump pressure with the ignition switch on motor not running is 3.1kg/cm2 but with the motor at idle it is 2.6kg/cm2 or 36.98 PSI.
I will try to clean it and see if I can see anything in there. I have a feeling that you are right about sucking up some trash into the pump. I did blow it out with a air gun and still no luck other than some old looking gas (rust color). Where did you locate the pressure requirements? Does the book have anything about flow requirements (gph or lph)? Thank you for helping me!
I have the Subaru Sambar English Factory Service Manual which has alot of good info in it (but nothing regarding ecvt transmissions or superchargers). It does not say anything about flow requirements. You mentioned the fuel that came out of your pump was rust colored maybe you need to spray some penetrating fluid or liquid wrench into the pump to unsieze (is that a word?) it.
Sorry for hopping back on an old post but I was scratching my head trying to figure out why my Sambar Manual lists 3kg/m2 when I cam across this. kg/cm2 makes WAY more sense for carborated engines than kg/m2.
