Carb rebuild kits and fuel pumps

[Gary H NC]

I am getting ready to order the kits to do my carbs on my 81 175.
I noticed the fuel pump kits are only 8 bucks apiece, is it worth doing the pump kits? I know replacement pumps are 75 bucks.
I don't think the pumps or carbs have ever been rebuilt on this engine.
The paint on the nuts holding the carbs on is still intact and the gaskets look original too.
Being i don't know the service history on this engine i thought doing the carbs and both fuel pumps for under 100 bucks in parts was a good idea.
Any suggestions on the rebuilds?
Still trying to find the reason for my low WOT rpms..

Also should i get the kits made by Mallory or spend a few bucks more and get OEM?

 

[HighTrim]

Re: Carb rebuild kits and fuel pumps

For 8 bucks a piece thats probably a better evening spent than hanging out with the wife I try not to fix what isnt broken, but that is fairly cheap preventive maintainence. I can tell by your boat you take care of your belongings. Im not 100 %, but I seem to recall reading on here some of the non OEM carb rebuild kits are short a few parts, the float I believe. Not usually something you need to change anyways, but something for you to look into. Im sure someone will be able to verify that. GL

 

[Barnacle_Bill]

Re: Carb rebuild kits and fuel pumps

Pumps are an easy job. Usually the diaphram is what goes. I don't recall every buying a carb kit that included the float. OEM or aftermarket. They were always extra.

 

[Gary H NC]

Re: Carb rebuild kits and fuel pumps

The OEM kits show the float included for 27 bucks.The Mallory kits with no floats are 17 bucks.
I have been getting a rough idle at times off and on. my WOT has slowly dropped off about 400 rpms.
Was just doing some checking and found i slight fuel leak where the fuel line hooks to the bottom of the top carb and another leak at the fuel line that goes to the bottom fuel pump.
Kind of seems strange they use zip ties for clamps..The zip ties i have will not tighten enough to keep it from leaking.
Special ties? Or can i use very small hose clamps?
Would minor leaks cause low top end?

 

[Silvertip]

Re: Carb rebuild kits and fuel pumps

On a boat there is no such thing as "a minor fuel leak". Fuel leaks can cause lean running. Lean running can cause rpm drops and more importantly, engine destruction. On an engine that old, the fuel lines have probably not been replaced either so doing that at the same time as the rebuilds would certainly be a good thing. Hard fuel lines cannot be properly sealed with zip ties.

 

[jtexas]

Re: Carb rebuild kits and fuel pumps

zip ties are OEM spec - try using two on there side by side. Is the leak from the pump nipple or the carb? or a "T" or some other fitting? maybe time for new fuel line?

I believe it's useless to do any other fuel delivery troubleshooting while fuel leaks exist - the fuel line has to stay pressurized for the motor to run right.

have some gasket remover and gasket sealer on hand for your pump rebuild.

My experience, she just always seems happier after a carb rebuild even when you don't find anything wrong during.

 

[Gary H NC]

Re: Carb rebuild kits and fuel pumps

I'm sure all the lines are original.No dry rot cracking but they are pretty stiff.
The leak on the pump looks like the nipple as well as the one carb.
Can i use standard fuel line? What size is it?
I may get the leaks fixed and do a test run before the carb rebuild..
Thanks guys!!

 

[Barnacle_Bill]

Re: Carb rebuild kits and fuel pumps

If you use the ty wraps be sure to use black ones. They are made for outdoor use. At least thats the way it use to be back when we used thousands of them in telephone work. They don't get hard like the white ones.

 

[Gary H NC]

Re: Carb rebuild kits and fuel pumps

I'm going to look for the ones with the metal catch in the end.I used to have some and can't find them but they were very strong and you can get them real tight without stripping the catch out.