1968 3hp Lightwin Fuel Pump

[film495]

I've done just about everything else on this motor and the only thing that bugs me because it is 40 years old is the fuel pump. I could do some test on it, but I think I'd like to either swap it with a new one or put new seals and all that in it. Question is - should I replace the pump or can I get a kit to refirb the existing one? Where is a good place to get said pump or refirb kit?

My take on why it dies once in a while (after reading a lot on this forum) is that the fuel pump can't keep up at WOT, so the carb runs dry - but the last few spins before she completely cuts out - sends some more fuel into the carb, so it can just be pulled. Although, last time it did this - the bulb was soft, so - everything else between the tank and the carb is new, so - that has to be a fuel pump issue that will only get worse no?

 

[film495]

Re: 1968 3hp Lightwin Fuel Pump

http://www.sschapterpsa.com/ramblings/Rebuilding_fuelpump.htm

If this is the correct pump - I'd rather just get a rebuilt kit if there is one. Any ideas where to get such a thing?

http://www.boatingsolutions.com/JohnsonEvinrude-OMC-Fuel-Pump-Kit-25-14HP--P7004C1617.aspx?UserID=4745432&SessionID=ZjMbBRv88Fm{ayaxq4w1

is this the right one?

 

[DC2Gooney]

Re: 1968 3hp Lightwin Fuel Pump

3 HP Lightwin??
Is the fuel tank remote, with a delivery hose,
or is it a half-gallon ring arount the power head (engine)..??

Gooney

http://www.sschapterpsa.com/ramblings/Rebuilding_fuelpump.htm

If this is the correct pump - I'd rather just get a rebuilt kit if there is one. Any ideas where to get such a thing?

http://www.boatingsolutions.com/JohnsonEvinrude-OMC-Fuel-Pump-Kit-25-14HP--P7004C1617.aspx?UserID=4745432&SessionID=ZjMbBRv88Fm{ayaxq4w1

is this the right one?

 

[tx1961whaler]

Re: 1968 3hp Lightwin Fuel Pump

A Sierra 18-7350 would probably work. It is a bit thicker than the original fuel pump, so you'd have to make sure it clears the engine cover. I just replaced the fuel pump on my 1970 6 HP with one, and it cleared the cover fine. Replacing the fuel lines would be a wise move, also.
Available here at iboats:
http://www.iboats.com/Sierra_18_735...6107551--**********.482979184--view_id.174139

 

[tashasdaddy]

Re: 1968 3hp Lightwin Fuel Pump

i agree with tx1961whaler. i just did the one on my 67 3hp.

 

[film495]

Re: 1968 3hp Lightwin Fuel Pump

it is an original remote tank, 3 gallon, all the lines were just replaced and inline fuel filters were put between tank and fuel filter and fuel filter and carb.

I had looked at that replacement pump, but I think I'd rather just put a kit into the original part, well then it is the original part, and also - I don't have to worry about fitting under the cowl top. Although, that is about half the price I've seen for replacement pumps, and I'm glad to know that one will work. Maybe I'll sit on this for a while since I'm burnt on working on the motor and it is going OK for now.

 

[F_R]

Re: 1968 3hp Lightwin Fuel Pump

You should be made aware that those style pumps are not all alike on the inside. In fact some of them were crap. Depending on just which one you have, the repair kit may or may not work. Unfortunatly, I don't know how to tell without taking it apart.

There is a reason OMC said those pumps are not repairable. I suggest a new pump and be done with it.

 

[film495]

Re: 1968 3hp Lightwin Fuel Pump

I went with the kit

http://www.sschapterpsa.com/ramblings/Rebuilding_fuelpump.htm

18-7823

followed the instructions and after a little tinkering it works fine. I don't know if the old one really had any issues, but it seems to be working correctly and after 40+ years, can't hurt. It seems like the motor runs a little faster and is a little less likely to stall out at low RPM now, but I can't really do a test until tomorrow in the daylight. I've timed from the beach to one of the islands at 2:15 every time, so I'll see how some performance testing goes when I get a chance.

 

[film495]

that kit worked until this year. for whatever reason it would stall every 1/2 hour or hour. sat in a garage lastfew years, cleaned it up, new pull cord, carb clean, fuel lines. got it running in a bucket and figured that was good enough to try in the lake. same thing, like every 1/2 hour it would just stall for no reason and then restart fine. I put a replacement pump on it - and it no longer does this, no stall nothing, just runs. it was however, not that simple. the gasket that came with the fuel pump was like 1/4 inch thick, and the screws that came with it were longer too, but the original ones were not and I wasn't going to be able to use them with the new pump. So, but the thread did not match, and I almost put them it, the diameter was correct, but the thread was most definitely finer. Glad I did not put them in and muck it up. I installed it without the gasket, and the originals screws fit, but then I don't have any gasket at all between the pump and the crank. I figured good enough for now and ran it, well, and for a long time, multiple times. I'll have to remember to just cut a thinner gasket and put one on there.

 

[Crosbyman]

14 year old post ... best to start a new one !!