'76 70 HP Johnson Fuel Pump Rebuild

[eavega]

I have a '76 70 HP Johnson (70EL76D) that I suspect has a faulty fuel pump. Although the repair manual states that the pump is not servicable, iBoats had a fuel pump rebuild kit for this motor. I am in the process of rebuilding the pump, but the kid came with no instructions and I need some guidance.

1. Does anyone have a blow-up of the fuel pump? I took pictures as I disassembled the pump, but would feel better with an actual diagram or blow-up of all the parts to make sure everything is where it should be.

2. Do I need to put any kind of gasket sealer between the layers? There is a gasket between the top metal plate and the bottom metal plate. When I disassembled the fuel pump, the existing gasket was pretty much adhered to the plastic part of the pump. I've cleaned most of that off, but didn't know if it needed adhesive when put back together and if so, what type

Any help would be appreciated. I'd rather not have to chuck the whole thing and spring for an $80 fuel pump if a $10 fuel pump rebuild kit will suffice.

Thanks.

Rgds

 

[mrcrabs]

Re: '76 70 HP Johnson Fuel Pump Rebuild

I did this myself for a 1975 70hp last spring, I used the Iboats kit that I suppose your getting, cost around 11$ from my J/E dealer.
I simply cleaned the gasket and diaphragm surfaces, reused the springs & plastic hats that hold up the new diaphragm cause they don't come in the kit??? but other model kits have them???...used no sealer and it was leak less and ran all of last summer w/no problem's.

Watch out for the springs when you dissemble.

 

[Vic.S]

Re: '76 70 HP Johnson Fuel Pump Rebuild

post deleted due to criticism .

 

[mrcrabs]

Re: '76 70 HP Johnson Fuel Pump Rebuild

Vic me thinks that just not a helpful link for rebuilding a 75, 70hp looper....one should actually just take there time, these pumps are so simple....just make sure the gasket and diaphram & gasket surface's are clean w/no gouges in the plastic body, using sealer is a good way to have a leak, and don't mix the hoses up when you put it back on...IMHO

 

[eavega]

Re: '76 70 HP Johnson Fuel Pump Rebuild

Thanks Mrcrabs, that is exactly what I needed!

I've rebuilt a fuel pump once before (well, not really rebuilt it, just replaced the diaphragm) with good results. I was aware of the springs and caps that can shoot every which way when you are disassembling. I have it all torn down and have the metal parts in "parts cleaner" to make sure I get all of the old gasket off. It looked pretty simple; two springs, two plastic caps, the diaphragm, two internal gaskets and the rubber fuel filter gasket. I just wanted the diagram so I don't second-guess myself. Thanks also for the answer regarding the gasket sealer. I will set it all up dry.

rgds

 

[the machinist]

Re: '76 70 HP Johnson Fuel Pump Rebuild

If you go back to the head of this forum & under the FAQ down near the bottom, you will find a link to my 9.9 /15 repairs. Also here is a link to a copy of the factory info sheet http://www.sschapterpsa.com/ramblings/Rebuilding_fuelpump.htm for these fuel pumps.

About all of the fuel pumps were the same for many OMC motors in those years. I am not dead sure but it appears the posted schematic (above) is for the later 1987 + version, the older 76 should be a totally different fuel pump.

 

[eavega]

Re: '76 70 HP Johnson Fuel Pump Rebuild

I am not dead sure but it appears the posted schematic (above) is for the later 1987 + version, the older 76 should be a totally different fuel pump.

Nope. With the exception of a couple of small pieces, the posted schematic is identical to the fuel pump I just disassembled.

Rgds

 

[eavega]

Re: '76 70 HP Johnson Fuel Pump Rebuild

Just as a final word to any that may turn up this thread when searching, my fuel pump rebuild was a success. The diagram posted was a big help in getting the gaskets right. The most challenging parts of the re-build was cleaning the old adhered gasked off of the metal and plastic parts. Getting it all off was a matter of a dremmel tool, a very steady hand, and a lot of patience. The only gotcha I can think of was getting the diaphragm on in such a way that it wasn't crimped or bunched up against the plastic caps. The small spring-loaded plastic cap at the top of the pump would stretch the diaphragm out the wrong way and the pump wouldn't work. The solution seemed to that if you fully compressed the spring, the stem on the plastic cap would push through a small hole in the back of the pump housing. By carefully holding the stem in place with a pair of needle-nosed pliers (thus compressing the spring and moving the plastic cap flush with the pump housing) you are able to sandwich the diaphragm correctly between the metallic back of the pump housing and the middle plastic piece. Once you secured the pump all together you could let go of the plastic stem and it returns to the appropriate position. A quick "suck and blow" test will let you know that you did it right (You should be able to blow but not suck air through the top plastic connector in the pump which is the fuel in. You should also be able to suck but not blow through the middle brass connector, which is the fuel out). Thanks again to all who helped me save about $70.

Rgds

 

[levi_tsk]

Re: '76 70 HP Johnson Fuel Pump Rebuild

just as an FYI if you buy the oem BRP kit it comes with VERY detailed instuctions and its only a couple dollars more - i just bought two, one for my 1956 fastwin and one for my 1981 johnson 140 the 140 was 18.00 shipped and the fastwin one was 14.00 its well worth the extra dollar or two to get the oem kit because of the dirrections included in the kit

 

[eavega]

Re: '76 70 HP Johnson Fuel Pump Rebuild

but is there an OEM kit? The maintenance manual for my motor says very specifically that the fuel pump is not to be serviced, but rather replaced if it fails.

-E

 

[levi_tsk]

Re: '76 70 HP Johnson Fuel Pump Rebuild

yeah they make em for all the motors now, the part number you would have been looking for was 393103, my guys got it for 14.99 plus 2.89 shipping

my manual says the same thing but i think they changed their policy after a few years