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zzion
04-22-2013, 03:29 PM
I have a g54b engine in top condition. Last june I put a napa el fuel pump on it. May have been thr ethinole but it worked perfect till Feburary then quite pumping. Still ran but wouldnt push fuel,. Took it back to napa they replaced it 8monthes old. I put the new one on it ram for 3 days and went south. It has great pressure but runs 20 seconds and quites. Napa dealer said there is something wrong with my tank but there is not. Any way I'm el pump shy now and won't to put the mech pump back on. I'm a lttle confused as to where the hoses go. The pump is marked in,out, and nothing on one which I consider the return. Given that the in means from tank and out means to carb and return goes where? there are 2 connections to the carb mikuni 1 pointed down 1 pointed towards the fuel pump with a small cover on it. I thought the 1 pointed down was from the out on the fuel pump and the 1 pointed sideways towards the fuel pump was from the unmarked "return the fuel pump. The pump works fine in My hand but when connected it diesn't have myuch pressure.
Can some one tell me how it connects? there is a line on the dr side of the carb that conects to the tank I'm assuming is the return line.
Thanks for the help
zz

camoit
04-22-2013, 07:22 PM
Is this an electric pump or mechanical pump you are using?
Also have you replaced the fuel filter?
If it's an electrical pump then you need to be with in 12 inches of the tank. It's more preferred, to be below the fuel level or as close to the bottom of the tank as you can. They will push better then they pull.

zzion
04-22-2013, 08:33 PM
I had an electric pump mounted on the frame 4" from the tank and beneth it.
I ordered a new mechanical pump today. I never had a problem except it lost prime once.
I misplaced my haynes repair manual. Which should a good pic of the lines.
I put an old mechanical pump on it seems to work a little then quit.
The fuel filter is new.
Ill have the new pump in the morning.
zz



Is this an electric pump or mechanical pump you are using?
Also have you replaced the fuel filter?
If it's an electrical pump then you need to be with in 12 inches of the tank. It's more preferred, to be below the fuel level or as close to the bottom of the tank as you can. They will push better then they pull.

camoit
04-22-2013, 08:55 PM
Look in the manual section. We have a factory first gen manual and there is a late model Haynes under the over 216 manuals area. Look for the montero.

BradMph
04-22-2013, 10:47 PM
Picture of a mechanical pump if yours is similar
http://www.mightyram50.net/vbulletin/showwiki.php?title=Fuel+Management+System:Mechanic al+Fuel+Pump+Diagram

Andy 2
04-25-2013, 07:28 PM
The line pointing down on the carb leads to the float bowl. The line pointing towards the fuel pump flows through to the return line on the drivers side. So you are right, The one pointing down goes to the pump outlet. The one pointing toward the pump connects to the unmarked. My mechanical pump has a plastic spacer between it and the cylinder head. Without it the pump won't last long as it will get over stroked by the cam.