Mercury 1150 thunderbolt - can I install an electric fuel pump without issue?

[Billet Works]

Hey all, I'm new to the forum here but this is my second Hydrostream. It's got a Mercury 1150 Thunderbolt out back but my fuel pump is out and squiring fuel through splits in the pump housing. I'd like to just ditch it and put on a low psi electric pump but wanted to see if it'll cause me issues and see what pressure pump would be ideal.

I've got to tear into the motor anyway to swap out the harness and rebuild the carbs, would be a great time to knock out the pump as well.

I've searched a lot without finding the exact answer I'm looking for. Any help is greatly appreciated!

I'll get some pics of the Viper in the next few days to post up.

Don

 

[Barnacle_Bill]

Re: Mercury 1150 thunderbolt - can I install an electric fuel pump without issue?

Not a good idea for safety reasons.

 

[Faztbullet]

Re: Mercury 1150 thunderbolt - can I install an electric fuel pump without issue?

Only if you use the Holley "red" marine fuel pump as it meets U.S. Coast Guard regulations. Wire it in thru a solid state relay that energizes off the stator, as that way it will only turn on when engine is running. You can put a "primer" button on dash to bypass relay to primer engine....

 

[Billet Works]

Re: Mercury 1150 thunderbolt - can I install an electric fuel pump without issue?

Holley red is what I had in mind...that's what I had on my johnson powered vector. Thanks for the tip on the primer button. What pressure pump would best suit the 1150?

Cant thank y'all enough for the replies. At this point, my other option is machining a new pump housing for the stock fuel pump...figured electric would be easier. I do have my own cnc on standby just in case tho.

Don

 

[JWH0420]

Re: Mercury 1150 thunderbolt - can I install an electric fuel pump without issue?

umm somthing about this electric replacement stuff... if the housing for one of fuel pump housings is cracked and there are 3 of them if i am not mistaken if u intend to bypass them u will need somthing to block off the holes to the intake side of the case aka take the housings place for the one that is cracked not to mention the price of those pumps and instalation mats wouldnt a used fuel pump housing and some rebuild kits be a better option that is unless ur set on electric pump for reason other than cost of repair w existing system

 

[Billet Works]

Re: Mercury 1150 thunderbolt - can I install an electric fuel pump without issue?

I may be misunderstanding completely here, but my motor has one mechanical fuel pump. It is fed off of crank case pressure so I understand blocking off the pulse lines. My concern with picking up a used fuel pump housing (if I can find one) is the possibility of it being in less than optimal condition and continuing to fight this battle. Id just assume draw up a billet housing and machine a fresh one before I put an eBay special on it.

The way I'm seeing it is, I block off the pulse lines and run a new fuel line from the quick connect straight to the carbs. Then between my tank and my quick connect I route it through the Holley red. Wire the new pump and bypass switch in and go.

I just don't like the fact that when the housing began leaking, on my recently rebuilt stock fuel pump, it squirted gas all over the motor while still running. I love havin a 70's tower of power on my 79 viper and would like to avoid fires.

All this said, I am pulling the pump off tomorrow to closer inspect and see if I can save it...but at this point I wanted to see what other options I had, if any.

I'm open to all input and appreciate every bit of it.

Don

 

[JWH0420]

Re: Mercury 1150 thunderbolt - can I install an electric fuel pump without issue?

i am not familiar with rebuilding one of these pumps as of yet i own a tower of power 1150 maybe i am mistaken and missunderstood the purpose of the other housings but there are 3 housings involved in the fuel pump part of things. as for using a used replacement housing i cant see how it would be under par unless it was damaged or flawed which i would think u would see beforehand. the other point would be the safety u mentioned if u did put a electric pump on it and for some reason a carb or line leaked its gonna spray everywhere unless its enough pressure loss to kill the engine just the same

 

[Billet Works]

Re: Mercury 1150 thunderbolt - can I install an electric fuel pump without issue?

One pump, three main parts to the pump assembly. A carb or carb line that leaks will spray fuel regardless of mechanical or electric fuel pump. I rebuilt my stock pump last year, so I have had it apart before, and used the boat all last summer.

Hair line cracks and small imperfections are pretty tough to spot on my internet pics.

 

[JWH0420]

Re: Mercury 1150 thunderbolt - can I install an electric fuel pump without issue?

What are the other housings that share lines and split fuel feed to carbs on mine... and w pump on boat if u leak before motor its bein pumped into bilge

 

[Billet Works]

Re: Mercury 1150 thunderbolt - can I install an electric fuel pump without issue?

Part of the fuel system. Scroll half way down this page for a breakdown of the fuel pump itself. http://forums.iboats.com/showthread.php?t=210649

Regardless of pump location, a fuel leak before motor will go into bilge. My point was, installing an electric pump will eliminate the leaky old mechanical fuel pump housing that is plaguing me currently by spraying fuel all over my motor. When I rebuilt my pump last year it had broken seals and sprayed fuel everywhere then as well. Anyway, the argument that an electric pump (if installed/wired properly) would be any less safe than a mechanical pump doesn't make sense to me...hence the reason I am seaming out knowledgable advise here.

 

[JWH0420]

Re: Mercury 1150 thunderbolt - can I install an electric fuel pump without issue?

Ok did some homework quick.... 76 1150s have 2 options for fuel pump setup depending on serial # so technically we are both right there is a single pump setup as well as multiple pump setup... as for thesafetything a fuel line onboard theboat w a opening and a mechanical pump will be a dribble leak and most probably draw air into line a leak post pump w electrical will push presurizedfuel out at much greater rate

 

[Billet Works]

Re: Mercury 1150 thunderbolt - can I install an electric fuel pump without issue?

We are talkin about a 5-6 psi pump here, i believe. I didn't think any had 3 pumps. I do know of the dual pump setup.