| T O P I C R E V I E W |
| brucepinpoint |
Posted - May 27 2012 : 09:11:14
Great day on the sassafras.............then running at 4200 RPM the motor died. It sounded like fuel starvation. Pulled the fuel pump and there was a broken spring and no oil. I am correct that there is an oil resivare in the sea water/fuel pump? It is a 1993 Mercrusiesr 7.4 B1. Do I have to replace the whole pump-there is a piece that pushes against the fuel pump arm that is loose inside the housing.Why would there be no oil in ths housing? Thanks for any help!!!! |
| 11 L A T E S T R E P L I E S (Newest First) |
| j-d |
Posted - May 29 2012 : 21:26:07
Good idea. Just collect PAMikee's source in case you need to replace the fuel pump part of this combo. If the original ran this long, it gave you pretty good service. Hopefully the new unit will run as well. |
| brucepinpoint |
Posted - May 29 2012 : 19:55:52
Issue resolved-bought a new unit. I learned they can be rebuilt but since this is both fuel and water I didn't want to take any chances.Thanks for all the replies!!!! |
| Pa Mikee |
Posted - May 28 2012 : 22:06:37
I wish I could be of more help but it's been a few years since I worked on mine. Can you restate what you mean by the cam is loose? Are you referring to the slip ring? |
| brucepinpoint |
Posted - May 28 2012 : 20:06:47
Thanks guys for the comments. The reason i think I may need a new unit is the cam that pushes the fuel pump arm is loose. What do you think? |
| Pa Mikee |
Posted - May 28 2012 : 19:15:04
I have the same fuel/water pump on my 1992 7.4L B1. Not sure why the oil resivior was empty on yours. Mine was filled with water due to bad seal. All I had to do was disassemble and replace the seal. My fuel pump would leak a little gas into the resivior and dilute it. I bought a new Merc fuel pump. Went to the auto parts store to buy the gasket. While talking to the parts guy he and saying how much I paid for a fuel pump; he cross referenced the pump and they could have gotten the exact pump for almost half the price. The only difference was his would not have been painted black. Yes, it had the connection to go to the carb if diaphram failed and let gas leak. |
| j-d |
Posted - May 27 2012 : 22:24:37
Just noticed on the page linked above that there's a raw water pump kit without the mechanical fuel pump designated "with electric fuel pump." Of course you'd still need the electric pump and the related safety switch (usually oil pressure) and wiring. |
| j-d |
Posted - May 27 2012 : 20:18:03
found the pricey thing on several sites. Our own sponsor, Boatfix.com, has it at $516 new and complete. That price was about average. I still don't know if yours can be serviced/overhauled in any way, or how it's lubricated.
http://www.boatfix.com/bykeywordmerc.asp?textfield=46-807151&texttype=2
Every source I found showed rebuild kits for only the water pump portion of these units. About all I can offer is that it may be less expensive long run to change the unit out than the labor time to repair it.
An option somebody here might have taken would be replace water pump with a plain one and install a marine-approved electric fuel pump. I'm assuming all MerC's ingenuity came from GM omitting the mechanical fuel pump mounting boss from their engine blocks. Oddly, our 1996 small block still has and uses it. |
| j-d |
Posted - May 27 2012 : 19:11:53
I've never worked on one. I searched it out to encourage comments by others. I also don't have much luck looking up the service manual, but there's one on line here. Help should be on the way. |
| brucepinpoint |
Posted - May 27 2012 : 16:29:57
Yes! That's it.it was bone dry.I guess that's why the cam inside is rattling around. Does the whole unit have to be replaced? |
| brucepinpoint |
Posted - May 27 2012 : 16:29:15
Yes! That's it.it was bone dry.I guess that's why the com inside is rattling around. Does the whole unit have to be replaced? |
| j-d |
Posted - May 27 2012 : 12:44:03
is it an assembly that looks like this?
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