J10 Loosing power going up hill in high third

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VOX
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Re: J10 Loosing power going up hill in high third

Post by VOX »

BEAVER wrote:Thanks so much! I will try a regulator. The weber specs are in the truck at the dealership. The carb was purchased from weber to replace the Carter that was in the truck. Any special regulator suggestions?
this won't fix your problem, if anything it'll compound it. your problem is a restriction in fuel flow and/or a vacuum leak. also have you checked to make sure your float level is set correctly and your clutch isn't slipping when going uphill?
Keith

1980 Wagoneer
1973 J10
1975 Cherokee Chief

letank
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Re: J10 Loosing power going up hill in high third

Post by letank »

Stuka wrote:
I am running a Holley regulator with a gauge.

Image
So, who is watching the gauge when you drive?

Debatting about putting a hole in the hood to see the gauge, where I will put some louvers latter. I need to figure out my flooding while cutting off the throttle at high speed. Or installing a video camera! My pressure is good at idle and under acceleration and cutting the throttle off in the driveway.
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)
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Stuka
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Re: J10 Loosing power going up hill in high third

Post by Stuka »

letank wrote:
Stuka wrote:
I am running a Holley regulator with a gauge.

Image
So, who is watching the gauge when you drive?

Debatting about putting a hole in the hood to see the gauge, where I will put some louvers latter. I need to figure out my flooding while cutting off the throttle at high speed. Or installing a video camera! My pressure is good at idle and under acceleration and cutting the throttle off in the driveway.
The gauge is there for setting it. I don't watch it constantly :)

Are you running a regulator? At high RPM the pressure climbs way up on the stock pump.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

letank
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Re: J10 Loosing power going up hill in high third

Post by letank »

Stuka wrote:
The gauge is there for setting it. I don't watch it constantly :)

Are you running a regulator? At high RPM the pressure climbs way up on the stock pump.
I have a self regulated carter epump, I guess the hole in the hood seems like a necessity for the sake of it! But a high rpm w a 360.... I do not think that I have gone over 4K.
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)

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BEAVER
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Re: J10 Loosing power going up hill in high third

Post by BEAVER »

You guys were right! The dealership screwed up the adjustments on the new weber. I cant even drive it in first. Either they will fix it back to specs or I will have to have it towed to my mechanic.
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Stuka
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Re: J10 Loosing power going up hill in high third

Post by Stuka »

BEAVER wrote:You guys were right! The dealership screwed up the adjustments on the new weber. I cant even drive it in first. Either they will fix it back to specs or I will have to have it towed to my mechanic.
I have the instructions scanned into a PDF here: stuka.fsjnetwork.com/fsj/carb/weber-manual.pdf

Towards the end is a troubleshooting page, may help you work through what you are seeing. It also contains a page on how to properly calibrate it.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

serehill
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Re: J10 Loosing power going up hill in high third

Post by serehill »

Interesting this is real familiar. I bought a 258 4 speed J10 Honcho about 5 months ago that was doing the same thing since I'm not a mechanical pump guy the first thing I did was put an electric pump on it. It ran better but not perfect so I pulled the tank because it had some kind of restriction. I found the stainless sock had disintegrated & stopped the pick up about half way. I bought all new parts & replaced the pick up & left off the sock. That made it better but every time I opened up the secondary it would still run out of fuel. I pulled the fuel system apart again & found the fuel line restricted between the tank to the motor. Trash in the fuel line. I took a compressor & blew a ton of junk out of the line. Then put it back together & now like my Cherokee that's been set up for years the same way it runs like a clock. A red Holley fuel pump at the tank. No regulators nothing else just a filter out of the tank then to the pump then to the VENTED filter at the front. Then to to the Weber. With the vented filter on the front there is no need for a regulator. The vented fuel filter works just like a regulator. My opinion & my solution but it works just fine. I looks really clean under the hood. Tons of solutions your choice & good luck. The solution is most likely simple. a break down of the entire system will find it.

Another real issue here is the possibility of a hole in the fuel line sucking air. Always a possibility. This would be in between the pump & the tank. there's a lot to be said for a pump at the rear pushing instead of a mechanical at the front. Every vehicle today has that type of system for a reason & it's not solely fuel injection.


PSI is not the key although you do need to stay in spec. GPH's are the key.

Of course all this is dependent on you fixing what the UH mechanic screwed up.
Last edited by serehill on Fri May 09, 2014 1:21 pm, edited 1 time in total.
1980 Honcho 258 4 speed mostly stock with 4 " lift.

WIP

You know the rude dude from IFSJA


1980 Cherokee wrangled & mangled
MSD complete system
Eddy intake
Holley 650
Comp cam 270H
4" Rusty's
Ramsey 12K winch
208
Built to drive not sit in the garage.


No longer strangled. I didn't build it for anyone else.
If you can't improve it why waste your time?
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haminawag
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Re: J10 Loosing power going up hill in high third

Post by haminawag »

serehill wrote:PSI is not the key although you do need to stay in spec. GPM's are the key.
Really? Exactly how many gallons per hour does your Jeep drink? Sounds awfully thirsty to me. :lol:
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Ham-in-a-Wag
1967 Plymouth Fury
1979 Wagoneer
2000 RAV4

serehill
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Re: J10 Loosing power going up hill in high third

Post by serehill »

haminawag wrote:
serehill wrote:PSI is not the key although you do need to stay in spec. GPM's are the key.
Really? Exactly how many gallons per hour does your Jeep drink? Sounds awfully thirsty to me. :lol:
Really Doesn't matter how much pressure you have if you're not getting any fuel. :P
1980 Honcho 258 4 speed mostly stock with 4 " lift.

WIP

You know the rude dude from IFSJA


1980 Cherokee wrangled & mangled
MSD complete system
Eddy intake
Holley 650
Comp cam 270H
4" Rusty's
Ramsey 12K winch
208
Built to drive not sit in the garage.


No longer strangled. I didn't build it for anyone else.
If you can't improve it why waste your time?
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