40 horse Mercury bogging down at full throttle

[flyingdelorian]

Hey everybody.The motor runs great for a minute or two then bogs down at full throttle. I can pump the bulb and the engine will pick back up and run ok until I stop pumping the bulb then it bogs back down. The bulb is never going really soft just a little less tight then when i pump it. I am thinking either a blockage in the fuel line or a weak pump. Where is the cheapest place to get a fuel pump for a 40 horse Merc? Also, I just bought the boat and don't know the year model of the motor. How can I find out what year model it is? By the way, I was happy to find a forum where I could read and ask questions, thanks for having this site up!

 

[saumon]

Re: 40 horse Mercury bogging down at full throttle

To order parts and to know the model years, we need the serial number, wich is either 7 digits or a letter followed by 6 digits (located on a sticker on the starboard side of the transom bracket and/or stamped on a 1' silvery round "plug" located beside the spark plug hole on the block).

And you won't need a "fuel pump", only a diaphragm kit at 20$ or so, wich contain the wearable parts of the fuel pump. Very easy to do.

 

[flyingdelorian]

Re: 40 horse Mercury bogging down at full throttle

The serial number for the motor is 06237457. By your statement about the diaphram kit, I assume that is what you beleive to be my problem?

 

[saumon]

Re: 40 horse Mercury bogging down at full throttle

Could be and look like that, but if I could tell for sure, i'd be rich!

Yours is a 1983.

Parts look-up found here:

http://www.mercruiserparts.com/selectDocs.asp?doc_nbr=90627

Here's what you need:
55278A1 ----DIAPHRAGM KIT $4.72

I'm not familiar with your engine, but if it has the carbs with the integral fuel pumps you'll need 2 of these kits. If the fuel pump is separate, only 1.

 

[flyingdelorian]

Re: 40 horse Mercury bogging down at full throttle

I think I found the culpret. I drained the tank and found a thin layer of water. I have cleaned the tank and will fill up with fresh gas and try it out as soon as it gets daylight. I will post here with the results. I have another question about disabling the oil mixing system but I will start a new thread for that. Thanks for your help.