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Unread 11-29-2012, 10:09 AM   #1
Renegad87
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Mechanical fuel pump upgrade

I have a 1987 Jeep Wrangler with the inline six and a weber 38 on it and I want to get ride of the mechanical fuel pump and go with an electric one. Does anyone know the best way to do this? Is there a kit?

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Unread 11-29-2012, 03:49 PM   #2
laffman
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This is what I run in my Jeep.

Carter Fuel Pump
Holley Safety Switch
Painless Performance Pump Relay
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Unread 11-29-2012, 04:13 PM   #3
uhohthe50
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Subscribed.. I'm curious about this too
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Unread 11-29-2012, 06:18 PM   #4
uhohthe50
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Quote:
Originally Posted by laffman View Post
What did you put in place of the old mechanical pump?
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Unread 11-29-2012, 06:51 PM   #5
Old4X
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Quote:
Originally Posted by uhohthe50 View Post
What did you put in place of the old mechanical pump?

Block off plates are available. But The mechanical fuel pump is the most reliable way to feed a carb. The only use I would have for an elect pump is as a boost pump for starting after sitting a week or more.
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Unread 11-29-2012, 08:34 PM   #6
uhohthe50
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Quote:
Originally Posted by Old4X View Post
Block off plates are available. But The mechanical fuel pump is the most reliable way to feed a carb. The only use I would have for an elect pump is as a boost pump for starting after sitting a week or more.
I think I found it:
http://www.summitracing.com/parts/sum-402035
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Unread 11-30-2012, 08:57 AM   #7
booboowv77
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I would leave the mechanical on as a back up in case the electric one fails.
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Unread 11-30-2012, 09:05 AM   #8
Jax89Jeeper
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Quote:
Originally Posted by booboowv77
I would leave the mechanical on as a back up in case the electric one fails.
If you don't disconnect the fuel lines, the mech pump will act as a restricion to the elec pump and if the mech pump is over powered you'd blow the diaphragm. If you disconnect the fuel lines and leave it in place, it will fail fom being ran dry. The fuel coming thru cools the pump much like it does an electric one. IMO the Mech fuel pump is an advantage over electric and would leave it in place (K.I.S.S. method). A mech pump is much less likely to fail and your carb does not need any more fuel pressure than what it provides. If you must go electric, get a block off plate.
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Unread 11-30-2012, 09:47 AM   #9
Jeepsr4me
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You can get these 7 psi pumps at just about any parts house. Last one I bought was like 22 bucks, even came with a inline filter before it. Remember electric pumps like to push fuel not pull it. So mount it LOW like on the frame rail. I never liked the mech ones on the block. WHEN they leak, they always do, they fill the oil pan full of fuel and ruin bearings.
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Unread 11-30-2012, 03:52 PM   #10
booboowv77
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Quote:
Originally Posted by Jax89Jeeper View Post
If you don't disconnect the fuel lines, the mech pump will act as a restricion to the elec pump and if the mech pump is over powered you'd blow the diaphragm. If you disconnect the fuel lines and leave it in place, it will fail fom being ran dry. The fuel coming thru cools the pump much like it does an electric one. IMO the Mech fuel pump is an advantage over electric and would leave it in place (K.I.S.S. method). A mech pump is much less likely to fail and your carb does not need any more fuel pressure than what it provides. If you must go electric, get a block off plate.
Sorry I swore I read it somewhere about leaving the Mechanical on as a backup would work. Good to know it won't.
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Unread 11-30-2012, 06:08 PM   #11
Jax89Jeeper
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Quote:
Originally Posted by booboowv77

Sorry I swore I read it somewhere about leaving the Mechanical on as a backup would work. Good to know it won't.
Well you can leave it inplace to plug the hole..... but it would not be of any use as a back-up.
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Unread 12-01-2012, 08:53 AM   #12
Renegad87
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Awesome thanks for the info. Another question I'd like to ask is the order of components starting from the tank. My current understanding follows this setup:

Tank
Fuel Pump w/integrated filter (Mounted by tank)
Fuel Filter w/return line (Engine Bay)
Fuel Pressure Regulator w/gauge (Engine Bay)
Carb

Some people have placed the FPR before the filter and I don't see why.
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Unread 12-02-2012, 07:44 AM   #13
Ksyrium
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Quote:
Originally Posted by Renegad87 View Post
My current understanding follows this setup:

Tank
Fuel Pump w/integrated filter (Mounted by tank)
Fuel Filter w/return line (Engine Bay)
Fuel Pressure Regulator w/gauge (Engine Bay)
Carb

Some people have placed the FPR before the filter and I don't see why.
It is my understanding is that if you use the Carter fuel pump, you should not need the regulator.
I read about that here
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Unread 12-03-2012, 10:02 AM   #14
laffman
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Quote:
Originally Posted by Renegad87 View Post
Awesome thanks for the info. Another question I'd like to ask is the order of components starting from the tank. My current understanding follows this setup:

Tank
Fuel Pump w/integrated filter (Mounted by tank)
Fuel Filter w/return line (Engine Bay)
Fuel Pressure Regulator w/gauge (Engine Bay)
Carb

Some people have placed the FPR before the filter and I don't see why.
With my Carter pump, I run a filter between the tank and the pump. The Carter doesn't have an intgrated filter. The rest of your setup looks just like mine.

Quote:
Originally Posted by Ksyrium View Post
It is my understanding is that if you use the Carter fuel pump, you should not need the regulator.
I read about that here
I still needed the regulator with my Carter pump. It's pushing 6 psi, which is too much for my Weber 38. It was flooding. I installed a Redline regulator. I'm running 3 psi now.

Redline regulator
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Unread 12-03-2012, 04:15 PM   #15
Jax89Jeeper
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Quote:
Originally Posted by laffman

I still needed the regulator with my Carter pump. It's pushing 6 psi, which is too much for my Weber 38. It was flooding. I installed a Redline regulator. I'm running 3 psi now.

Redline regulator
Yeah, with the Weber carbs, any fuel pump needs a regulator.... Even the stock unit.
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