7.4 Bravo water pump driven fuel pump

[snowbrd84]

On to the next issue in this 2 months new to me boat. Bought it knowing it had a power loss issue, but it was still usable and a good deal. First thing was compression test which lead me to a wiped cam lobe. Replaced camshaft with help from folks here. Water test yesterday still had issue. Still won't go above mid 3000 rpm at about 24-28mph. 97 sea ray 270. Should do upper 30s at 4500 rpm wot.

Spec is 17.25 r 23p prop. I have brand new 17.25r 21p on. So not over propped.

Pulled the anti siphon today. It was good.

Pulled the fuel pump, it looks to be possibly the issue. The oil reservoir was all the way at the gasket and oil reekedof gas. The roller thing that drives the fuel pump has a ton of play. Is this toast? Cab it be rebuilt. See video.

 

[tpenfield]

My Twin engine Formula had engines with those combo fuel/water pump housings. It seemed like they leaked often. I found that the lever arm on the fuel pump would also wear down. Slip the belt of the water pump pulley and turn the pulley by hand to see if you are getting cam action. I cannot recall how the cam within the housing is designed.

The fuel pump diaphragm probably has a hole/tear in it, thus the gasoline smell. Best to get a new fuel pump. Hopefully the housing itself is still good. IIRC, those things are pricey and may be hard to find.

 

[Scott Danforth]

If you have the room, I would probably switch to a crank mounted raw water pump and use a Carter universal marine water pump and wire it with an oil pressure switch/ relay

 

[snowbrd84]

Yeah I'm switching to electric and installing block off plate for old mounting spot. That bearing requires a ton of effort to replace.

That Carter looks to be hard to get. Might do Holley Red unless u I can find something a little cheaper.

 

[kenny nunez]

The Carter is by far better than the Holley. They cost more for a good reason. You want the oil pressure safety switch also.

 

[snowbrd84]

The Carter is by far better than the Holley. They cost more for a good reason. You want the oil pressure safety switch also.

Just bought the carter on Jegs for $100 and next day shipping. Ordered the carter safety switch earlier. Hope this fixes the issue. Only thing left is the Ignition Module, which is NLA. Will check timing at 3500 rpm to see if advance is rhere or not. If not then ill install a DUI distributor and hopefully be done. Those are 8 to 10 weeks to get though according to their website.

 

[Scott Danforth]

Carter is in stock at summit

Carter P4389 Carter Universal Rotary Vane Electric Fuel Pumps | Summit Racing

Free Shipping - Carter Universal Rotary Vane Electric Fuel Pumps with qualifying orders of $109. Shop Fuel Pumps at Summit Racing.

www.summitracing.com

And the following is absolutely true. The Holley pump is over-priced junk

The Carter is by far better than the Holley. They cost more for a good reason. You want the oil pressure safety switch also.

NAPA has oil pressure switches in stock

 

[flashback]

I bought a carter last year and it's done a good job this summer and I think I may get a spare just in case..
Looks like you're in need of some new pulley belts as well... don't wait for it to break the engine will overheat quickly...

 

[eric102]

On to the next issue in this 2 months new to me boat. Bought it knowing it had a power loss issue, but it was still usable and a good deal. First thing was compression test which lead me to a wiped cam lobe. Replaced camshaft with help from folks here. Water test yesterday still had issue. Still won't go above mid 3000 rpm at about 24-28mph. 97 sea ray 270. Should do upper 30s at 4500 rpm wot.

Spec is 17.25 r 23p prop. I have brand new 17.25r 21p on. So not over propped.

Pulled the anti siphon today. It was good.

Pulled the fuel pump, it looks to be possibly the issue. The oil reservoir was all the way at the gasket and oil reekedof gas. The roller thing that drives the fuel pump has a ton of play. Is this toast? Cab it be rebuilt. See video.

I have the 91 version of your boat/engine and gas leaking into the oil is fairly common, seems like the fuel pump starts leaking within a few years of replacement. As for the performance issue have you replaced any of the ignition components? I replaced the ignition module, rotor ,cap and wires and it made a huge difference. The boat jumps up on to plane now as where before it took its time.

 

[04fxdwgi25]

Actually, those raw water pump drives with the fuel pump are pretty easy to rebuild (bearings and seals) and parts are readily available.

That ring flopping around is normal.

The mechanical fuel pump # are: (believe the OEM is made by Airtex)
OEM part # - 861677T
Carter # - M60932
Sierra # - 18-8860
Airtex # - 60932