Belt driven raw water fuel pump assembly
 

Greetings all, looks like I’m into break out thousands again territory. I thought I had an oil leak but it seems to be coming from the belt driven fuel pump which I understand has gear lube inside with shaft bearings that go bad.

has anyone had any luck with the aftermarket replacements which are in the 200-300 range or is this a only buy Mercruiser 1,100 part?

has anyone had these pumps rebuild successfully?

Thanks
Duane

I know a guy that’s running the Amazon ones and not having any issues at all. I’m sure others will chime in.

https://a.co/d/09MU3B4K

one for the pro column!! Thanks.

I would definitely do some homework on this.

You don't have much to lose by trying one of those out. The real concern is the fuel pump. I keep buying the merc overpriced pumps, that start to leak within a year or 2 and they trash the seal on the sea pumps. I tear the fuel pumps down and cannot find anywhere they are leaking.

Love the translations
but that store has all kinds of things

these pumps can be rebuilt. I have done a few with good results. I have changed the bearings out to the 2RS style (double rubber sealed) that way i removed the rubber seal on the inside section of the bearings for oil to get inside and still have another seal on the outside of the bearing to help keep things inside the pump assembly. Sort of a double seal on each end of the shaft.

Helmwurst, I cant remember what the brand of pump it was but i have used a regular automotive fuel pump before...the only thing that different is how it leaks the fuel out in case of a diaphragm rupture. The standard auto version just has a hole to leak onto the ground since they are out in the open air. On a boat i have taken the pump body apart and drilled and taped the hole to install a nipple and ran a small 1/8" fuel line up tot he carb to dump into the engine in case of rupture...thats the way the old merc style pumps were done anyway...

^^^^ Wally that would be great if you remember what pump you used. I cannot believe Holley does not make one. The pumps I see on Amazon have a roll pin that holds the arm in place. I would NOT recommend one of those. Even the Carter's marine fuel pump has those, and we put those on a friend's boat last year and one failed in the first 2 hours. Wore out the roll pin and the hole to the point that the arm fell off when I removed the pump. The other engine pump was starting to show wear in the same area.
If you can, due you remember the part number of the seals that you used in the sea pumps? I could not find a cross reference to the factory seals and I like the idea of using a 2RS seal.

I honestly don't remember what fuel pump i used :( ...that was like 25yrs ago now....i want to say it was an Edelbrock pump i used but it may have been a holley just the same...sorry


https://cimg2.ibsrv.net/gimg/www.off...e805ef70e8.jpg
Old style pump
https://cimg3.ibsrv.net/gimg/www.off...8083c8e9a7.jpg
bearings for old style pump
https://cimg4.ibsrv.net/gimg/www.off...e4c83a418f.jpg
Inner seal taken out
https://cimg5.ibsrv.net/gimg/www.off...42578bf304.jpg
Seals for old style pump
https://cimg1.ibsrv.net/gimg/www.off...10e93d1232.jpg
Fuel pump style seawater pump
https://cimg2.ibsrv.net/gimg/www.off...45215843bc.jpg
Dust cap removed
https://cimg3.ibsrv.net/gimg/www.off...1adcdfe5e5.jpg
must remove retaining ring
https://cimg4.ibsrv.net/gimg/www.off...8658218f81.jpg
retaining ring removed
https://cimg5.ibsrv.net/gimg/www.off...5b073d82fc.jpg
Shaft assembly removed
https://cimg6.ibsrv.net/gimg/www.off...f16a36f46d.jpg
Shaft assembly taken apart
https://cimg7.ibsrv.net/gimg/www.off...e52ef31ac4.jpg
Drilled and tapped a drain plug for easier maint.


The bearings for the pumps with the fuel pumps on them....... i think are the same size as the non fuel pump style pumps. And i know those are the 6204 bearings cause i have a pic of them. I know those are 20mm ID for the shaft, 47mm OD and they have a 14mm Width
So i would take the pump apart and measure the old ones to be sure. Then get them in a 2RS version and just take out one of the seals on the inside where it will be filled with oil. You may need to clean out the bearing grease in there just so it doesn't cross contaminate the oil.
The actual seals i don't know what the part numbers are for those. I do have the part numbers for the old style pumps....there's 3 of them. the two small ones are a 7450 and the one large dust cap behind the pulley is a 7690
I really suck at taking pics consistently. I have a habit that when i start a project i just plow right through it without stopping to take pics and if i do i usually missed like 10 steps along the way! :D

Have you ever changed the gear lube?? It gets fuel diluted and over pressurizes.
The sea pump rebuild kits are on ebay, but you need a hydrailic press do it.