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mattyboy
05-01-2010, 05:04 PM
can you guys give me a quick schooling on the pro and cons of electric pumps

what pressure do I need also what are the do's and don'ts

gcarter
05-01-2010, 06:49 PM
Buizilla and Mr Fixxxxxittt can give you their reasons (maybe they even like mechanical), but I like the consistancy and control an electric pump gives you.
Holley makes their marine "Blue" pump w/a regulator that can be mounted in a number of convenient locations.
Be sure and use an oil pressure operated safety switch! :yes:

BUIZILLA
05-01-2010, 07:20 PM
what are you trying to accomplish? and why?

Zinger
05-01-2010, 07:30 PM
You may need a return line on some electric pumps, you must mount it as low as possible do to the poor suction. Relay, wires and sensor. I currently running a mallory 140 without any problem. But if I a manual pump for my 502 I would use it the only problem is I'm running a serpertine belt. I have not seen one set-up this way not sure if you change the pulley on it if it would work. The cost to buy the seapump housing and pump I can buy two mallary electric pumps. I read people having failures with both types of pumps, I would say a manual pump would be safter to run.

mattyboy
05-01-2010, 07:53 PM
what are you trying to accomplish? and why?


I'm trying to get the boat running for the dustoff ;)


what I thought was some kind of water seperator in the fuel line turns out to be an automotive 5-9 psi electric fuel pump with all the leads rusted off it. found the other end of the leads

nothing special going on here just a ford 302

VetteLT193
05-01-2010, 07:53 PM
Personally this is a no brainer.

With Electric:
Turn on the key, let the pump prime
pump the throttle
turn to start...
done deal

Mechanical... badududududududududududududududududududududududud
badudududududududududududud
badududududududududud
badududududududududa finally start

Get a holley marine pump. done deal, good to go.

Conquistador_del_mar
05-01-2010, 08:08 PM
can you guys give me a quick schooling on the pro and cons of electric pumps

what pressure do I need also what are the do's and don'ts

I like them for certain applications. I can't think of any particular cons if you rig it up correctly. Like was already pointed out, you do not need to turn the motor over to get fuel to the carburetor like the mechanical pumps. You will have to get one large enough to handle your engine needs. A red holley does not need a regulator but most if not all the larger capacity pumps need a regulator to get the pressure down to around 8PSI or less. I always rig in a constant duty solenoid to supply the power from a good source using the ignition wire to trigger the solenoid - this way you don't run much current through the ignition switch. My two cents, Bill

mrfixxall
05-01-2010, 08:11 PM
what vette said,, i have been running a electric fuel pump in my x for 20 + yrs,i would't go with out one..if your going to replace it go with a mallory. theirs to many problems with the holley plus they are vary loud..also i always drain my tank over the winter and its nice to just disconnect the line going to the carberator and hook my extended fuel line and shove it into my suburban and just turn the key on..

this one should be enough to power your boat,you wont need a regulator because its only 6 psi...Run the fuel line through your filter first then to the fuel pump...

http://www.summitracing.com/parts/MAA-4070M/

penbroke
05-01-2010, 08:24 PM
what vette said,, i have been running a electric fuel pump in my x for 20 + yrs,i would't go with out one..if your going to replace it go with a mallory. theirs to many problems with the holley plus they are vary loud..also i always drain my tank over the winter and its nice to just disconnect the line going to the carberator and hook my extended fuel line and shove it into my suburban and just turn the key on..

this one should be enough to power your boat,you wont need a regulator because its only 6 psi...Run the fuel line through your filter first then to the fuel pump...

http://www.summitracing.com/parts/MAA-4070M/


Will a pump like that cycle on and off or run all the time that the key is on?


Frank
Just wondering...

VetteLT193
05-01-2010, 08:34 PM
Fixx is correct... The Holley is kind of loud but over CMI's... lucky to hear anything. Since fixx suggests the other one I wouldn't hesitate to use it

VetteLT193
05-01-2010, 08:36 PM
Will a pump like that cycle on and off or run all the time that the key is on?
Frank
Just wondering...

The Holley blue pump runs all the time when activated. the regulator is separate post pump.

I assume they are all like that but you might find one different. I have run 3 different electric pumps in carbed marine applications and all have run all the time.

mrfixxall
05-01-2010, 09:19 PM
Will a pump like that cycle on and off or run all the time that the key is on?


Frank
Just wondering...


yes it runs all the time with the key on, you can hook the wires yo a oil pressure sender and hook the + wire the the sender so the pump will only be on while the engine is running..

BUIZILLA
05-01-2010, 09:21 PM
hook the + wire the the sender so the pump will only be on while the engine is running..pump won't work not cranking/cranking until it gets oil pressure either :cool:

gcarter
05-01-2010, 09:38 PM
pump won't work not cranking/cranking until it gets oil pressure either :cool:

Yep, that's what the safety switch is good for.
It runs when it's cranking and when there's oil pressure.
It don't run when there's no oil pressure and when it's not cranking.

gcarter
05-01-2010, 10:13 PM
So here's the Holley safety switch;

http://cgi.ebay.com/ebaymotors/Holley-Safety-Fuel-Pressure-Switch-12-810-/370373751381?cmd=ViewItem&pt=Motors_Car_Truck_Parts_Accessories&hash=item563bfef255

You put in a tee where the oil pressure sender is and the sender runs on one side of the tee and the safety switch on the other side.

And here's the Holley "blue" pump w/regulator;

http://cgi.ebay.com/ebaymotors/Holley-712-802-1-Blue-Marine-Electric-Fuel-Pump-110gph-/390189464519?cmd=ViewItem&pt=Motors_Car_Truck_Parts_Accessories&hash=item5ad91abbc7

mattyboy
05-01-2010, 10:23 PM
clear as mud

BUIZILLA
05-01-2010, 10:25 PM
FYI... if your going to buy a Holley pump and use ethanol fuel you MAY have an issue, these pumps and regulators shown here are for gasoline... which we haven't had for a year now.. you need the 120 pump and an alky suitable regulator..

mrfixxall
05-01-2010, 10:30 PM
Jim,George,,thats what i ment,the safety switch :)

gcarter
05-01-2010, 10:43 PM
clear as mud

Matty, the switch has three lines to it.
One from the starter switch, one from the ignition, and one to the fuel pump which isn't switched, it's connected all the time.
When the starter is engaged, power goes to the fuel pump while the engine is cranking.
When the oil pressure comes up, the ignition wire will be connected to the fuel pump. I think it remains connected until the oil pressure falls below 5 PSI or so.
When the engine dies and the ignition switch is on, the fuel pump doesn't run because it's a normally open switch that only closes when there's oil pressure.
So the fuel pump only runs when when the starter is cranking and when there's oil pressure.

gcarter
05-01-2010, 10:50 PM
FYI... if your going to buy a Holley pump and use ethanol fuel you MAY have an issue, these pumps and regulators shown here are for gasoline... which we haven't had for a year now.. you need the 120 pump and an alky suitable regulator..

So Jim, are you talking about this pump?
It claims it's good for alcohol.

http://www.holley.com/12-125.asp

mattyboy
05-01-2010, 10:59 PM
this was one recomended by a friend

http://cgi.ebay.com/ebaymotors/Carter-P4389-Marine-Electric-Fuel-Pump-72gph-6psi-12v-_W0QQcmdZViewItemQQhashZitem5ad9296182QQitemZ39019 0424450QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccesso ries

gcarter
05-01-2010, 11:03 PM
Matty, it looks good, it seems to be compatible, maybe doesn't need a regulator, but I don't see a drain port.......
Maybe the picture isn't of the marine version.

BUIZILLA
05-02-2010, 06:28 AM
Matty.... that Carter pump is an excellent choice for YOUR application.... get a 5 blade relay from Radio Shack and your good_to_go. :yes:

mattyboy
05-02-2010, 07:27 AM
now a few other questions.

there is not alot of fuel line in this system cause the tank is closer than normal. it doesn't have a shut off valve and I would like to add one, a water seperator and fuel filter

the existing fuel lines/fittings are 5/16ths is that ok or do I need 3/8ths when all said and done there will be maybe 5-6 feet of line between everything using the gray fire retardant usgc fuel hose

i am going to put the shut off on the tank outlet then to a seperator then to an inline filter then to the pump then the carb

the pumps talk about a 30 inch distance is that a vertical limit or a true distance limit to have the correct psi at the carb or is it from the tank to the pump?

thanks

BUIZILLA
05-02-2010, 07:34 AM
pic's are mandatory at this point.. :wink:

mattyboy
05-02-2010, 07:51 AM
pics of it now it is still a mess or when I am finished,come to think of it there won't be much difference ;)

the fuel system is ripped out an laying on the work bench

so what do we want to see?? I take some shots today

gcarter
05-02-2010, 08:04 AM
Matty, I reccomend this Aeroquip hose between the fuel tank shutoff and your filter seperator;

http://dunham.thomasnet.com/item/ul-hose-hydraulic-hose-aeroquip-aqp-hydraulic-hose/aeroquip-fc234-fuel-and-oil/fc234-08?&seo=110&bc=100|1518|1239|1507|3002338

It's fire retardant, USCG approved, wire armored, and WON'T be the cause of any fire you may ever have.
Any Aeroquip shop will have it.
This is the 7/16" size, they also supply a 5/16", but no 3/8" size.

mattyboy
05-02-2010, 08:10 AM
I was thinking of putting the shut off directly on the tank pickup it is accessible basically the fill and the outlet are on the back of the tank which comes out right by the bulkhead in front of the motor

gcarter
05-02-2010, 08:26 AM
That is close, isn't it?
I think I'd like to see pictures too.
But your thinking is correct. I always install a shut off at the pickup and another just in front of the filter............but they've always been further apart than what you're describing.

BUIZILLA
05-02-2010, 08:28 AM
that hose is very good but a wierd size... it is sold as #8, which is .500 ID, but it's .410 inside dia., which is larger than 3/8, but smaller than 7/16, by approx the same denominator.... or .090 smaller than advertised.. that's a ton of difference..

gcarter
05-02-2010, 08:32 AM
that hose is very good but a wierd size... it is sold as #8, which is .500 ID, but it's .410 inside dia., which is larger than 3/8, but smaller than 7/16, by approx the same denominator.... or .090 smaller than advertised.. that's a ton of difference..

I agree. I think most folks end up using the 5/16" size, and that would probably be OK for Matty's application.

gcarter
05-02-2010, 08:34 AM
Here's all your choices and you can see what I mean.

http://dunham.thomasnet.com/viewitems/ul-hose-hydraulic-hose-aeroquip-aqp-hydraulic-hose/aeroquip-fc234-fuel-and-oil?&bc=100|1518|1239|1507

BUIZILLA
05-02-2010, 08:37 AM
I may have, after 6 years, just stumbled on a Critter issue... :bonk:

gcarter
05-02-2010, 08:44 AM
I may have, after 6 years, just stumbled on a Critter issue... :bonk:

Is it what I'm thinkin'?

mattyboy
05-02-2010, 09:35 AM
go easy it is my phone cam , me taking the pics , and it is a work in progress



the original tank was replaced and sealed in 1995 they put a 40 gallon tank under the floor from the foot locker back basically under the bench seat what you see is the back of the tank which goes forward under the seat locker then the floor locker which was removed

the fill is on the port side just ahead of the clamshell vent the tank just infront of the motor

they must have used Fixx's trick the tank is bone dry

hope that helps

gcarter
05-02-2010, 10:05 AM
Jut curious, what's doing most of the retention of the tank?
That appears to be an anti-syphon device screwed into the pickup. I usually remove that and screw the shut off valve into the pickup at that point. I think Worst Marine offers a street (male and female ends) shut off valve. Then you screw in an adapter to screw into the end of the shut off valve (NPT) and SAE (or whatever hose end you choose) on the other end of the adapter. Then the hose is screwed onto the adapter.
The other end of the hose is screwed onto the filter/seperator. The anti syphon device can be screwed into the other side of the filter seperator where you would normally use push on hose.

mattyboy
05-02-2010, 10:33 AM
it is supported by foam in each corner it rests on neoprene strips and it thru bolted by brackets to the stringers front and back. the back one is just out of lens range in the pic

not in the budget for this year but the original tank will be replaced in it's original location when the deck is lifted sometime in the near future.

i was thinking of something like this for a shutoff

http://cgi.ebay.com/ebaymotors/Kantleak-M670C-N-3-8-Marine-Fuel-Shut-Off-Valve-_W0QQcmdZViewItemQQhashZitem1e5af2f46fQQitemZ13037 4890607QQptZBoatQ5fPartsQ5fAccessoriesQ5fGear

MOP
05-02-2010, 10:36 AM
Matty looking at the tank shot it looks like you have quite a mixture of fittings there, they should all be aluminum all others will react with the aluminum over time. It may be time to throw all that junk out and put a new pickup tube and anti siphon valve in, you really do not need a shut off they are not required when the tank is below where it feeds the engine. Anti siphon is a requirement!

gcarter
05-02-2010, 11:43 AM
Matty, the one you've chosen is fine.
I think this one is a bit smaller and gives you a lot of fitting options.
http://cgi.ebay.com/ebaymotors/Earls-230501-Fuel-Shut-Off-Valve-JEGS-/200463874634?cmd=ViewItem&pt=Other_Vehicle_Parts&hash=item2eac93fa4a
Materials aren't much of a problem since gasoline isn't an electrolite.

I wish I could find the one I used in the past.....maybe it's not made any more.