Carter seawater mounted pump question??
 

Probably a long shot but…
Just curious if anyone has ever upgraded the seawater mounted fuel pump on a Gen 5/6 motor. It is just a standard Carter pump so I believe that I could just swap the indexable part with the Carter Comp series (p/n 61045).
This pump has the –10 inlet and –8 outlet vs. the ¼ NPT holes that the standard pump has and also has a higher flow rating.

Thanks,
Dave

Yes,
I did it two years ago under the recommendation of someone at CP performance.
Because of that I ended up detonating the hell out of my brand new 502 and grenaded it. Fuel pressure was the last thing I checked ( I don't know why) and when I put a gauge on it , it was barely keeping the float bowls full (1050) .
My fault for not checking the fuel pressure first !:mad:

I did it with a couple of pumps from CV Products 2 years ago.

rbtnt and 26Scarab,
could you maybe clarify just a bit.
I believe the only thing unique to the marine fuel pump is the armature device.

26 Scarb, did you just buy a Carter 61045 and swap the lower unit or did you buy the upgrade from CP Performance which, I could be wrong, but I'm thinking is just a 61045 bottom unit.
If that's the case, then I can buy the entire pump from Summit or Jegs for $90 or I can buy half of it from CP for $150:rolleyes:

rbtnt, what is CV products?

thanks,
Dave

I'm using the "stock" pump lever assembly with the upper from the newer Holley Marine pumps. I maintain 6# with twin-carb blower motors. The Carters didn't use the size fittings I needed.

Nordic,
I bought the "upgrade" kit from CP.

I have since been told that the arm stroke ratio on the Merc pump than on a standard pump. In my case I believe it but other people are doing it with good results .

I have had a carter pump on my boat for two years. Works great.

Thanks Scarab26,
what do you mean by the arm ratio? I would be using the same arm so wouldn't this be a non issue? Confused ;o)

Cignificant,
just to clarify, you changed only the two piece pump body (inlet and outlet) and left the armature housing in tact to the sea water pump assembly.. Correct?
Which Holley pump?

Thanks,
Dave

Dave,

I'm using the stock lever assembly from Merc that bolts on the sea pump and a high output pump body from CV. The only thing I had to change was drilling the thread out of the screw holes on one of the units. I think I drilled the threads out of the lever assembly, both units had threaded holes. I then bought some stainless steal allen head screws to screw them together. I still use the green plastic hose from the pump to the flame arrester in case of pump failure.

The only way to buy the high output pump from CV is a complete pump with lever assembly.

Randy

That correct. Originally I had Holley pumps with 1/2" inlet/outlets. The "arms" had been cut and then welded so they would work with the sea water pumps. (I bought then from the OSO "parts for sale" section) They both went bad about the same time. Gas was leaking through the seal around the "arm" - I think the seal may have been damaged in the welding process.

Anyway, Holley no longer makes the 1/2" I/O pumps (I think the part# was 712-454-1). So I bought the 3/8" pumps. Holley's part number is 712-454-13. They match up to the bolt pattern on the stock Mercruiser "arms". Match the stock arms to the Holley "uppers" and that is what I have. It actually works better that the pumps with the 1/2" I/O.

Thanks Guys,
Cig,
looks like I'll be upgrading my pump either with the Holley or the Carter w/#8 & #10 fittings.
Sounds like either one will fit my seawater mounted armature housing (lever assy):D
Randy and 26Scarab,
thanks for the CV lead! I spoke with them at length and they are trying to work with Merc on this issue. They will sell just the billet bottom assembly unassembled for ~$150 or the billet assembly with a standard Carter housing for $175.
I think they want to design a full billet replacement which is what they're working with Merc on. Beautiful pumps!
For my application (this pump will only be priming my Aeromotive) the stock Comp Series Carter or Holley should do the trick!!
Thanks Again,
Dave
:cool:

Dave,

Thanks for the update on CV and what they are doing. I had to buy two complete pumps and come up with two merc pumps to make mine work. Their price of $175 for a complete pump, is a lot cheaper than what I paid.

Good luck and keep us posted on what you do and how it works out.

Randy

Randy,
remember that the $175 was for their billet bottom and standard Carter armature housing. They said, if they were to market the full billet marine pump and a full billet armatur housing it would be closer to $350.
Lots of money (and fuel delivery:D )
Later,
Dave

Dave,
I remember someone saying to check Merc's larger HP engines, like the 800SC. I think they had a higher volume fuel pump that would work. But maybe that was for the block mount style vs sea pump. Maybe something there will line up.

Rick

Glad you guys are having luck , all I know is I purchased the Carter upgrade kit(basically the bottow of the pump with -8 fittings) and it did not work for me.
Oh well , live and learn. In a way it was a good thing because now I have a 540 instead of a 502 !:D

:confused: I guess I just don't get it or something?????? Why do you use a Merc pump to "prime" an Aeromotive pump????

The Aeromotive can build a lot of pressure and flow and it WILL suck fuel "uphill" (out of the tanks) thru a filter to the pump and then thru another filter and still maintain up to 60# of pressure out of an A1000 pump???? So, why the mechanical???
Is there something I am missing here????:confused:

I'm not sure of NordicHeat's application, but I'm running the mechanicals on a N/A 540 - 650hp without any other pump.

I had Mallory electrics before and had a 3 fail in a very short period of time. I heard they had a bad batch of pumps 4 or 5 yrs ago when I was trying them.

Hey BlownFormula,

You’re probably right, I may not need the mechanical pump at all; but all it can do is help. I have struggled in the past with rotary vane pumps pulling out of the tanks, which is why they want massive lines on the intake side of the pump. However I would think that small pickups in the tanks altogether nullifies that approach. Obviously you'll only flow as much as the smallest orafice in your entire system regardless of the inlet size.

In my previous setup, I originally got a lot of cavitation from the high pressure pump and the simple addition of the mechanical and a small reservoir allowed me to run appx 550+ hp with a small rated (45 gph at 43.5) EFI pump without any problems at all.
I understand Merc has returned to using the mechanical to feed the vane pump in their new HP applications as well.
They may have experienced some of the same problems.:(

Probably just cheap insurance, and I would also venture to say longer pump life from the Aeromotive. The mechanical running at very low pressure will always keep the Aero fed with all it can handle and allow it do what it needs to do best; push! I believe Brett (at Aero) told me that most failures to their pumps are caused by restrictive supply to the inlet.

Like I said, maybe it's not needed and indeed the Aeromotive pump can overcome a lot, but I just want to help it out a bit. It's a bridge I've crossed already and don't want to reinvent the wheel I suppose.

Speaking of crossed bridges; due to your regulator problem I have since relocated my regulator from the transom to right between the fuel rails. I’ve done this even before it has seen fuel! Thanks for the heads up.:D

Dave

Dave... What I was seeing was the potential, and you have to follow this closley......
Aeration, hence heat build up due to restricted (relative to smallest orfice size in system) flow. If the mechanical is pumping more fuel than the Aeromotive is passing thru to the injectors &/or the return line, then the mechanical is trying to "compress" the fuel (impossible !) resulting in boiling/aeration/cavitation of the fuel & pump. It seems the inlet side would still need to be as large as possible....AN-8 or 10 and the return being the same or only one size smaller than the supply.
Using the mechanical that way requires 3 fuel lines to the engine?? supply to mech pump, return to electric pump, fuel to regulator on engine! A lot of extra plumbing and therefore restriction. I understand the theory you are using, it just seems to be "redundant" in a way. :eek: hence, more expensive!!:D
I'm glad you got something out of my fuel troubles earlier this year. I wish I had known then what I know now!.....
Wait a minute...... didn't we say that about women also???:D :D

Another good point Blown..
One thing with the mechanical is they basically shut themselve off with bypass valves (if self regulated) at say 6-7 psi. So heat generation is probably minimal at best.
To take that a step further, my mech pump feeds a large Racor filter/seperator (4" x 8") that has the pickup lowered 3" inside of it. The pickup is a 3/4 pipe nipple and from there I can run a full #10 out of the Racor to the Aero. (Entire system is #8 otherwise) The Aero pressurizes the fuel rails and dumps through the regulator. The regulator returns thru a water chiller to the same Racor. My Racor filter is always ice cold so I do know that my fuel is very stable at that point which is where the big pump feeds from. I would think any high pressure vane pump would like that supply:D
Overkill:confused:
Probably...
Reliable:confused:
Absolutely:D

Might even give you a good limp home mode if the Aero ever crapped out (unlikely)
When in doubt, build it stout!!

I wish I had known then what I know now!.....
I think they even wrote a song about that:(

Later,
Dave