Mechanical to electric fuel pump 454

[WaterMike]

The mechanical fuel pump went out earlier this year and I replaced it with the same mech. pump and now the new one is leaking out of the top gasket. Really annoyed at $300 a pop, and looking to get rid of the excessive cranking at start up. Has anyone here converted to an electric fuel pump from the mechanical on a stock carb 454 motor? Mine is the bravo style unit (I believe it is called) where it is built into the water pump unit. I have not pulled the leaky new pump off, but from what I can see in my bilge fuel has pushed oil out of the oil filled bearing area of the water pump unit. Any tips or tricks for doing this?

 

[Croz]

I didn't do the conversion myself, but I have an electric pump for my 454 with stock carb. They will typically run the holly blue pump (14psi) with a regulator to have it at 7psi. I'm running a holly red pump on mine that comes at 7psi so there is no extra plumbing. I don't know about other pumps but I know the holly needs to be placed low so it pushes fuel rather than suck fuel. If this sounds off to someone who actually knows what they're talking about feel free to call me out.

 

[74 spectra20 v-drive]

I am an old school guy but thinking they have that pump on the drive unit because there is no fuel pump casting on the newer gen BBC's. I have always run electric pumps, is your concern how to eliminate to mechanical pump? can you post some pics, would like to see how this is set up?

 

[Deja_Vu]

Nordic just put in another mechanical fuel pump on my 454 recently. I asked the same question.
They recommended that I stick with the mechanical pump.

 

[mash on it]

Gen V 454, Berkeley drive, have had a Carter electric fuel pump on it since 1996. It has been replaced about 5 years ago.

Dan'l

 

[BUSTI]

I feed 2- 750cfn Holleys on an 8-71 with 6 lbs of boost with a red Holley which feeds a fuel log off of a stock mechanical pump. System only puts out 4.5 lbs. the key is it has fuel volume all the time. This is how Teague runs their stuff. Check their tech section on their website.

 

[farmo83]

I converted to an electric pump on my stock merc setup a few years ago. Long story but we thought there was an issue with the shaft driving the pump due to finding fuel in it and the problem ended up being a piece of wood caught in the fuel line.


It wasn’t too terrible a job to do, it has a breaker we mounted on the floor and it’s fused and run off the ignition switch, took me and dad a few hours to put in. I went with a holley red pump as for what I’m running I figured a regulator was just something that could go bad. It cranks a lot quicker and still has good pressure on the big end.


I will say this if you do go with electric put an inline filter before the pump. It will last a ton longer.


Hope this helps.

 

[welldigger00]

I run a clay smith mechanical in parallel with a malleroy electric to a manifold, then through a pair of regulators to a pair of quick fuels on my deal. I like the ability to set the fuel pressure before cranking, and then run on the mechanical at idle speeds, then if I’m in the secondaries for a prolonged period of time, I can run both pumps to share the load.


Sent from my iPad using Tapatalk

 

[WaterMike]

I am an old school guy but thinking they have that pump on the drive unit because there is no fuel pump casting on the newer gen BBC's. I have always run electric pumps, is your concern how to eliminate to mechanical pump? can you post some pics, would like to see how this is set up?

https://bpi.ebasicpower.com/shop/me...454-502-92-99-has-fuel-pump-mount-46-807151a8

This is a link to the raw water/fuel pump assembly. I know someone sells a block off plate for the top of the unit to eliminate it.

 

[WaterMike]

Nordic just put in another mechanical fuel pump on my 454 recently. I asked the same question.
They recommended that I stick with the mechanical pump.

Did they give a reason?

 

[Deja_Vu]

Did they give a reason?

They just said the stock Merc setup worked well and to stick with it.

 

[WaterMike]

Thanks for the replies from everyone. I called NAPA and they are going to swap it out when I take it off. For now I am going to just replace the Mechanical pump again to get the boat going. I am going to do some more research and try the conversion this winter when the shops are slower and not back logged for weeks like they are now. I will check out Teagues tech section BUSTI. Thinking about the excessive cranking at start up, it may have gotten worse with the pump leaking and draining all the fuel out of the line from the pump to the carb. Ill keep you guys posted on what I find in a week or two.

 

[Deja_Vu]

Nordic told me there are several fuel pumps that will fit that block.
I guess the one they just replaced for me wasn't the correct pump (automotive type) ...and it was only 4 years old...installed by Prestige.

 

[WaterMike]

The one I looked up on Marineengine.com for the Gen V (1992-1996) and VI (1996-1997) blocks is the same pump. Sierra Maine 18-8860, this is the same one I got from NAPA. Is this the right one?

Gen V
https://www.marineengine.com/parts/...03118-thru-0f800699/fuel-pump-and-fuel-filter

Gen VI
https://www.marineengine.com/parts/...00700-thru-0k999999/fuel-pump-and-fuel-filter

 

[Deja_Vu]

I think I got the Mercury Marine one for $265 but yeah the Sierra Marine is showing to be equivalent so you should be okay.

https://www.marineengine.com/newparts/part_details.php?pnum=MER861677T

 

[74 spectra20 v-drive]

https://bpi.ebasicpower.com/shop/me...454-502-92-99-has-fuel-pump-mount-46-807151a8

This is a link to the raw water/fuel pump assembly. I know someone sells a block off plate for the top of the unit to eliminate it.

Thank you for the link, as this was purely for my education... electric or mechanical, Ford or Chevy, its a choice and not that big of a deal. You could make a simple block off plate with some 1/4 to 3/8 aluminum and a gasket. I like the electric because you can turn the key on and fill up for carbs bowls, and not have to crank the engine to build pressure. I run a simple little carter on my flat and I run a Mallory on my Day cruiser, I like them both.

 

[rush1]

I'm going to replace my mechanical pump on my raw water pump but I'm going to spend the extra bucks and use an oem mercury pump. hopefully it will hold up as long as the original from 1997

 

[HitIt]

Are you talking about the accessory mounted raw water/fuel pump? Freaking hate that thing. Water, oil, and fuel all separated by a few o-rings and diaphragms. If this is what you are talking about, you are supposed to change the oil in the little reservoir ever 20 hours or something ridiculous like that.

I just replaced mine with an airtex. From what I hear, they are the oem for merc. $60 and you are done. Buy a few

https://www.amazon.com/gp/product/B002HTYRD8

 

[rush1]

I just changed the oil in my raw water pump housing, it was super black , plus on my housing there isn't drain hole had to suck the old oil out.

 

[HitIt]

I just changed the oil in my raw water pump housing, it was super black , plus on my housing there isn't drain hole had to suck the old oil out.

Last time I had mine out I drilled and tapped it for a drain hole. Makes it easier to service.

 

[WaterMike]

Are you talking about the accessory mounted raw water/fuel pump? Freaking hate that thing. Water, oil, and fuel all separated by a few o-rings and diaphragms. If this is what you are talking about, you are supposed to change the oil in the little reservoir ever 20 hours or something ridiculous like that.

I just replaced mine with an airtex. From what I hear, they are the oem for merc. $60 and you are done. Buy a few

https://www.amazon.com/gp/product/B002HTYRD8

That is a smoking deal! I believe the angle of the arm is different on those than mine cuz the earlier ones mount directly to the engine block.

Got my new mech pump installed and started it in the drive way. Going to watch it when I get out on the lake to make sure the seals don't leak.

 

[johnehr]

Sorry to respond to such a late thread. However, I'm encountering a lot of hesitation when getting above 2k rpms and/or in chop (it gets better over time) after upgrading from my mechanical pump to an electrical one. My mechanic is trying to source another "fuel line", but I'm guessing its a regulator, but think its hard to believe thats the issue that would cause hesitation at higher rpms. Are there any ideas what could cause the problem? Any common mistakes? I have a 1990 cobalt condurre 243 with the 454 7.4L Mercruiser.

 

[sintax]

I run a clay smith mechanical in parallel with a malleroy electric to a manifold, then through a pair of regulators to a pair of quick fuels on my deal. I like the ability to set the fuel pressure before cranking, and then run on the mechanical at idle speeds, then if I’m in the secondaries for a prolonged period of time, I can run both pumps to share the load.


Sent from my iPad using Tapatalk

This gives me a lot to think about and process.

I have been thinking about running an elec in parallel as well. If my boat does sit for a while, obviously the bowls dry out and I usually end up having to start w/ a bottle if its been a few weeks. I think the elec pump would help prime the system.

So you have your elec pump AFTER the mechanical ??

are you running dead head or return style regulators ?

 

[welldigger00]

It’s parallel to the mechanical, not in line , with check valves to prevent fuel from circulating back.