Need fuel pump rebuild kit?

[Spring]

Hi All at iboats, Well, I bought a nice 82 Astroglass 140 bass boat with an 83 Mariner 50ELPT ser.# 6367670 motor. All cylinders test at 100 psi with #3 being 105. Normally, the motor runs fine. However, at times, I have to pump the fuel line bulb to keep it running when it starts to die. It always happens at least once during an outing and sometimes more often than that. I have checked the fuel line from the tank inlet to the carbs and can find no air leaks. The fuel line did have some kind of plactic liner that had disintegrated that I removed and the fuel line was pinched between the lower carb and the engine block. I thought I had fixed it but the problem returned. I'm thinking now that the problem may be the fuel pump itself and searching for them has only confused me even more as there are multiple part numbers for this engine. I would like for someone to please id the correct part number for the fuel pumps for this engine. The closest I can come is part # 7815 from Mastertech Marine, http://www.maxrules.com/fixmercfuelpump.html. , but am unsure due to the part number of the engine. Can someone tell me if this is correct?
Thanks for any info that you can provide.
Dee

 

[Spring]

Re: Need fuel pump rebuild kit?

I may add that the engine will deplete the fuel in the fuel line to the bulb and the bulb will be empty. Squeezing the bulb a few times and the engine will pick back up and keep running. After doing this 1-2 or 3 times it will run ok for a while but if I fish and don't use the engine for 30 minutes or more I have to pump the bulb again when I restart the motor.
Any ideas anybody?

 

[alaskanassassin]

Re: Need fuel pump rebuild kit?

Same symptoms with my dad's merc 15hp, my old 15hp evinrude, and my buddy's 9.9 force. Fuel pump fixed it. Also, check all fuel fittings and clamps for air leaks. Squeeze the bulb up tight with the cover off your motor, and check for fuel leaks. You should be in good shape with a new fuel pump kit. The ethenol fuels are killing those fuel pumps, try to find real gasoline and use it every time if it available in your area. Otherwise count on replacing fuel lines and pumps a lot. Let us know how it goes.

 

[Spring]

Re: Need fuel pump rebuild kit?

Thanks for the response alaskanassassin. I have checked everything up to the fuel bowl/filter and just finished replacing the bulb with a new attwood and blowing out the fuel lines from the bulb to the fuel bowl/filter. Lines were clean and I can find no leaks of any kind. It still dies until I pump the bulb.
Looking at the carbs/pumps, it appears that new gaskets have been installed recently and a call to the po verified this. He said he had the carbs rebuilt with new pumps about 3 weeks before I bought it. I suppose mistakes can be made even by pros and I am looking at pulling the carbs for a look/see.
Just seems to me that if the pumps were bad that it would run poorly, or not, all the time instead of dieing momentarily like it does now? 98% of the time it runs good!

 

[alaskanassassin]

Re: Need fuel pump rebuild kit?

It will run fine on a pump that's going bad, with an issue once in a while. Take your pump apart and see if everything is correct inside. If this work was recently done, you may have gotten crud in the carbs afterword. Anyone else have any ideas? I am far from an expert, but seems to be exactly what I've dealt with in the past with bad fuel pumps.

 

[alaskanassassin]

Re: Need fuel pump rebuild kit?

You could have blown the new pump due to the pinched fuel line. check it.

 

[nathanhooper]

Re: Need fuel pump rebuild kit?

depleting the fuel in the line to the bulb almost sounds like the vent for the gas tank is clogged. Just a thought.

 

[Spring]

Re: Need fuel pump rebuild kit?

You could have blown the new pump due to the pinched fuel line. check it.

Next thing to do is check it. Thanks alaskanassassin.

 

[Spring]

Re: Need fuel pump rebuild kit?

depleting the fuel in the line to the bulb almost sounds like the vent for the gas tank is clogged. Just a thought.

That thought came up too so I ran the little 4-banger with the cap loosened with no improvement. I'm going to pull the carbs and check the pumps tomorrow. I keep ya'll informed of what I find.
Thanks for all the suggestions everybody.

 

[Spring]

Re: Need fuel pump rebuild kit?

I couldn't wait for tomorrow so I went ahead and removed the carbs to chk the pumps. Top carb looked great, clean with no debris inside and the pump screen was also clean. Bottom carb was a different story. I believe the po, most likely the mech., rebuilt the top carb but not the bottom carb. There was just too much difference in the cleaniness and overall condition. The pump screen was almost completely filled with crud, tiny bits of rubber and pieces of the plastic fuel line liner. How all this stuff got past the filter bowl just baffles the jeepers outa me. Anyway, I cleaned the crap out of it and replaced them both back onto the engine. Hooked up the muffs, pumped the bulb and smelled gas immediately. Damn, it's the bottom carbs pump cover leaking, bad. Don't see how unless I overtightened the + screw too tight and cracked it.
I guess I'll do it tomorrow after all..

ps- why does the icons not work?

 

[alaskanassassin]

Re: Need fuel pump rebuild kit?

Cool! Looks like you have the issue under control. The reason all that crap got by the screen is it was all tiny bits until they swelled up with fuel. Get that thing all cleaned up and sealed and let us know if it did the trick.

 

[Spring]

Re: Need fuel pump rebuild kit?

I think I fixed it! Won't know for sure till I get it on the lake this evening but it sure did run better than it ever has on the muffs. Did not die out like it used to and that is encouraging.
The plastic pump covers gave me a fit trying to seal them. Apparently, they are precision fitted and to seal they must be precision fitted again if one ever removes them. I had to lightly bevel the edges to get them to seat back into the recess against the cork gasket and had to make a new gasket for the top carb but managed to get them to stop leaking. Persistence is a good thing!

 

[Spring]

Re: Need fuel pump rebuild kit?

Just got back from the lake and it is still doing the same thing only not as often. It does idle better, planes quicker and seems to have a tad more power.
However, it still wants to die while trying to take off from idling at times. Once on plane it will run till you stop. It's just when you stop and try to take off again. I'm thinking that the pumps are weak and not receiving strong enough of a pulse from the engine to keep the fuel pressure up.
Anyone have any thoughts on this?

 

[abarron]

Re: Need fuel pump rebuild kit?

My 1974 850 Thunderbolt did the same thing,get a 5gal outboard tank,and line and a good bulb,and try it out.thats what i did and it ran great! i aso would ad some seafoam in my gas.this will tell you if you inboard tank is trashed, like my tank was.

 

[Spring]

Re: Need fuel pump rebuild kit?

I really think it's the fuel pumps, especially the bottom one since it looked much older than the top one. I have already disassembled, cleaned and reinstalled the carbs/pumps with some overall improvement but still have the dieing problem. Anyway I have new rebuild kits ordered along with new inlet covers, screens and gaskets. Hope that does the trick.

I know on weed eaters if that tiny screen in the carb is the least bit dirty it will not run right. They may look clean but they are not.

 

[Spring]

Re: Need fuel pump rebuild kit?

Is Seafoam worth it's salt? Could it really help my situation? I've heard a lot about this stuff but never used it.

 

[abarron]

Re: Need fuel pump rebuild kit?

It worked great for me! I also added a touch of Marvel Mistry Oil.