Help with rebuilding the Carter Mechanical Fuel Pump on my 3.7 Mercruiser 470.

[86Rinker19ft]

Hello all. I have a 3.7 Merc. with the factory Carter Mechanical fuel pump. Went down to the local marina and they happened to have the diaphram/rebuild kit in stock however, it did not come with the gasket that seals between the filter housing top and the check valve section of the fuel pump body. I went back and verified, that ONE gasket is not part of the rebuild kit......WHY NOT!!?? Anyways, I want to replace that and I think I may have figured that out. Now to the question at hand, how do I get the little rod that holds the armature into the fuel pump body out? It has a little brass plug that, when removed exposes a rod inside the body. If this rod were to be removed it SHOULD let that armature out (I assume) and I think that armature must have a fork like end that holds the main diaphram of the pump in place. I have searched the internet and these forums yet have not been able to come up with ANYTHING on rebuilding one of these fuel pumps. I have Mercruiser #8 manual (BIG thanks to Don) and it also says nothing about rebuilding this pump, aside from changing out the internal filter. So any advice is much appreciated.

 

[cr2k]

Re: Help with rebuilding the Carter Mechanical Fuel Pump on my 3.7 Mercruiser 470.

probably not rebuildable or parts are NLA.

 

[dccordell]

Re: Help with rebuilding the Carter Mechanical Fuel Pump on my 3.7 Mercruiser 470.

It's not that bad of a job, if you have instructions! When I did mine, I found this link on rebuilding a carter pump. It's not the exact pump that you have, but it is pretty darn close and the process is nearly identical. Very helpful, check it out!

I don't remember the gasket you are talking about, but I know which one. Seems like the kit I had did have that gasket, as I don't remember having to buy any other gaskets. The kit you have is a QuickSilver part, right?

Edit: Oh yeah, I just remembered I had a thread on this subject from quite a while ago. It may be of help, and it also shows how to get that pin out. There is a keeper clip inside the pump on that shaft that you have to get out with some needle nosed pliers, then pop that little cap off (brass?) from the outside of the pump where the pin is, then just grab the pin from the inside with the pliers and slide it out to the side where you removed that plug. Mine came out pretty easy. Check out that thread here.

 

[86Rinker19ft]

Re: Help with rebuilding the Carter Mechanical Fuel Pump on my 3.7 Mercruiser 470.

Thanks for the info dccordell, but after reading your entire post, it seems that your kit also was missing the gasket I was talking about, AND your kit seems to have contained less parts than the one I got. Mine includes: fuel filter and the base gasket for that, the main diaphram, the little shaft brass plug, and new mount gasket. As I read your post it seems that your kit only had the main diaphram and the gasket that goes to the base of the filter (direct quote from your post)- "All I got in the kit was the diaphragm and the gasket that goes on the filter and bowl." Your post does however EXACTLY answer my question, PLUS you have a pic! So tomorrow I will try removing that armature and see if I cant get it all back together, THANKS SO MUCH dccordell, and I will let you all know how it turns out. It DEFINITELY seems like the way to go over buying a new one!

 

[dccordell]

Re: Help with rebuilding the Carter Mechanical Fuel Pump on my 3.7 Mercruiser 470.

Yep it sure beats paying over $100 for a new pump...

Guess I should have read over my own post before posting it! I thought it came with the check valves and other stuff but I guess not. Anyways, glad it helped! Oh, I do remember it came with the new brass "plug" that goes on the outside, musta forgot to mention that in the thread.

Also, I remember that my check valves were sticking after I rebuilt the pump the first time, so I had to take it back apart and clean them. They will come out pretty easy, just try not to tear them up. Clean them up and make sure they will go in and out pretty easy and not bind up at all. If one of them isn't working, neither will the whole pump. IIRC, I took a toothpick and pushed them in and out making sure they would move easily.