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Fuel pump
Posted: Sat Jun 02, 2007 10:53 am
by Niclas
I was thinking of switching the civvy fuelpump with thins one
It's from a enginge marked 806279
So I can get vacuum to the wiper(s).
but how/where do I install the tubes/hooses ?
Is the a simpel way of checking the condition of the pump before I install it ?
I only have 12 days left before im going to do the check so I can get it street legal.
/N
Posted: Sun Jun 03, 2007 12:44 am
by wesk
"B" goes to the intake manifold and "A" goes to the wiper "T". When you operate the pump lever by hand you should feel suction at the "A" hole.
The top hole goes to the carb inlet. The top hole on the front side (not visible in your photo) is from the gas tank. When you operate the pump lever by hand you should feel suction at the top front hole.
There is also a vent hole in the middle of the pump facing away from the engine towards the fender.
Here's a photo of a M38/M38A1 series pump.

Posted: Sun Jun 03, 2007 2:47 am
by Niclas
thx for the help
My Went hole is plugged.
Anything I should do something about ?
/N
Posted: Sun Jun 03, 2007 11:14 am
by Niclas
The fuel pump didnt fit
some cut out hole is to small in the part that attach the engine to the frame.
Think my engine is to new. (not original engine)
/N
Posted: Sun Jun 03, 2007 11:38 am
by wesk
You may have the wrong front engine mount plate. The left mount ear should have had enough relief in it for the pump to fit. There is a CJ3B fuel/vacuum pump that was designed for the 3B/M606 with vacuum wipers.

Posted: Sun Jun 03, 2007 12:48 pm
by Niclas
You are rigth about the front mounting plate.
I have that fuel pump too.
but I think its the same size at the bottom as the other one.
And I have no clue where the current engine is from.
Engine no is 807895
/N
Posted: Sun Jun 03, 2007 3:42 pm
by Cantabria
Hello
front engine mount plate

Posted: Sun Dec 02, 2007 2:03 pm
by JustenWilson
Hey Wes, my "A" & "B" are backwards, would this cause a problem of some sort? Also i try using the pump handle on my fuel pump which should have been rebuilt is not getting any suction either. Also we had to make this fuel pump fit on the engine. BTW my old problem was a fuel pump problem. Tell me what you think.
PS i have the m38 mounting plate.
Posted: Mon Dec 03, 2007 2:06 am
by wesk
Reversing A & B will result in a loss of vacuum for the wipers and the pump's vacuum half will try to pressurize the crankcase. These ports have nothing to do with fuel delivery.
Not sure what you mean by
we had to make this fuel pump fit on the engine
Posted: Mon Dec 03, 2007 7:23 pm
by JustenWilson
well a budy of mine made some shims and shaved the fuel pump with a file until it fit, not so sure that it was done right. i have a electric fuel pump on it but of course i want to take it off.
Posted: Tue Dec 04, 2007 1:17 am
by wesk
The correct M38 fuel pump is spaced the correct distance from the cam lobe with a spacer. It would have been much easier for you to buy the spacer. Too close and the pressure is to high and too far and the pressure is too low.
Note the thick spacer between the gasket and the engine.