Seawater/Fuel pump
 

I bet this has been talked about but any input will help.We have 2003/ 500EFI with 250 hrs

Was in the boat checking things out and found oil on the bottom side of both pumps. Not so much to start dripping into the bilge...I did know that they ran lube in them but never spotted a leak so never checked them.I pulled the fill plugs and they are way over full...No water just oil and gas...Checked the tube running from the weep hole on the fuel pump and it is dry..Removed one of the fuel/water pumps tonight and every thing looks fine as far as the cam in the fuel pump is concerned..I love what you have to do just to drain the oil in this set up..:(

How bad do they leak? with 250 hrs..I find it interesting that the weep tube is dry but I have gas with the lube.

Will I be ok just putting them back together and keeping a close eye on the level to see what happens or should I replace the fuel pumps??

Can the pumps be rebuilt??

If I do replace the fuel pumps is there a pump that I should be checking out other than Mercurys??
Thanks for any help!!
Bob

No one has ever had this issue???

Yes I had my problem with one pump around the same hours found out after the fact merc wants us to change fluid every oil change bad design only one plug to fill with! after mine leaked put new one on, what needs to happen is drill and tap lower part of housing for a drain plug, for now I remove the fuel pump and wipe out the lube and refill and install new gasket I've got 500 hrs now it's another excuse to be in the hatch:D now

Bad engineering.... Been there...

They all leak. Just change the fluid once a year. Might as well do the impellors too while everything is apart.

525's are the same way. Gas get's into the shaft oil and breaks it down and will cause a failure. Every season I drain and replace with fresh drive oil.
I've setup a plastic syringe and flex tube to extract it on the every other years that I don't replace the Impeller. Make's it a quick change without having to pull the whole assembly!

Same here. I use a drill pump with a small ID silicone line attached and suck the old fluid out.

I thought I had read a post somewhere on the subject where some one had mentioned there were 2 plugs on his pump, and it came that way from Merc. Mine is a 1995 BBC. Wonder if Merc had the sense to put both a filler and a drain plug in the later models. Would be nice.

Now that I have them all apart and every thing looks ok I was going to do two things before I put it back together..

It will be very easy to drill and tap the bottom of the housing for a 1/8 pipe plug..

I found that the fill plug is the same thread as the magnetic plugs that goes in my lower unit. It will not interfere with anything in the housing so I thought it may be a good idea is check for metal when changing the lube..

Thanks for all the replies
Bob

Here's a thread from last summer. I use the syringe method mention above and do it when I change everything else every 25 hrs.
http://www.offshoreonly.com/forums/s...+seawater+pump

Just had both of mine off last weekend for water pump impellers. Mine have 2 plugs and both had alot of gas in them too. One seemed like more gas than lubricant. Where did the lube go? Dont see any leaks.

fuel in the lube seawater/fuel pump
 

wow! I'm a newbe to this..That is,,,to this sight and big boats!!We just went from a smaller boat to a bigger boat... We just got a 2003 Formula Fastec, it has twin 525 EFI's in it ...I guess we have one more thing to keep an eye on!..Found fuel in the lube for the seawater/fuel pump on both engines also!!!.:eek:.. Anyone know if merc has come up with a new fix or new base yet..From what I've been reading and researching,,, its the base thats leaking?? Anyone know the cost on rebuilding?

That setup is the biggest POS next to a damn Yugo to come down the pike in years...yes they love to fail, if you are getting fuel in the oil replace the fuel pump now, ck the bearings and keep a eye on the fluid...when they take out the bearing from the oil being contaminated from fuel it ain't cheap !

Any rule of thumb for swapping out the fuel pump prior to it starting to leak down? Change it out every two-years? Rather be proactive in saving the bearings as I know how much those things are!!! And how much a day on the water means to me!!

Engineering Marvel!!!

The diaphram on the fuel pump wears out and starts leaking into the oil . They all do this

have a 02 575sci and had the same problem. Replace the pumps last year and have about 50 hrs on them now and checked the oil and no sign of fuel. If theres fuel in the oil there bad, dont just change the oil change the pumps....

Ditto.

You could also tap the bottom and install a drain plug. I think some pumps actually had removable plugs on the bottom.

Is there a rebuild kit for the diaphragm or is there a aftermarket fuel pump? I'm guessing being its a Mercury Racing part you have to buy OEM. I'm addressing changing the lube on mine this year, but if they are leaking I might as well rebuild/replace the pumps while I'm at it.

What weight oil are you guys putting back in? I'm running 75W110 in my drives I'm guessing thats too heavy for this pump.

I'm also going to attempt to put a drain plug in mine while they are out. How did using the drain plug with a magnet on it work out?

I had to rebuild sea pump last year because the diluted oil took out the bearings and seized the pump up bad enough it brike the shaft. Anyways, I got my pump from Speed and Custom Marine (speedcustommarine.com). It was $95.00 plus the ride and it is the same oem pump other than it is not painted black.

http://www.offshoreonly.com/forums/g...fuel-pump.html going thru this right now,,,had a drain plug put in bottom for ez service,,new fuel pump also,,,cv marine fuel pumps makes a replacement fuel pump,,,not cheap tho http://www.cvproducts.com/Products.aspx?Search=fuel pump&CATID=10000441

Irish,,,i was wondering the same,,,this is what i found ,,hope it helps,,,http://www.offshoreonly.com/forums/g...el-pump-2.html