Author Topic: Dualjet cruising lean hesitation  (Read 36667 times)

Offline VileZambonie

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Re: Dualjet cruising lean hesitation
« Reply #30 on: August 11, 2024, 07:10:09 pm »
If you've validated your fuel volume and that there is not a feed issue, replace the ignition control module.
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Offline Scaryfastatx

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Re: Dualjet cruising lean hesitation
« Reply #31 on: August 12, 2024, 07:15:46 am »
If you've validated your fuel volume and that there is not a feed issue, replace the ignition control module.

It's a brand new GM module in the hei, the rest of the ignition is new as well

Pretty sure the pump plus the leak at the tank was the cause of my issues. Gonna get the Delphi warrantied and throw the old Carter I had back on there and see what it's pressure looks like

Offline Scaryfastatx

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Re: Dualjet cruising lean hesitation
« Reply #32 on: August 20, 2024, 08:59:03 am »
So the seller on amazon refused to warranty the Delphi pump, Amazon told me to call Delphi, they told me to email them and I got a 1 line reply, warranty through reseller, we dont deal directly with consumers.... GREAT JOB amazon! well fool me once

I got a new lifetime warranty pump from Orielly and slapped it on, and fuel pressure is now pretty constant, jumps between 6-8psi, revving it up drops to 4 but never below

no bubbles in the line

but took it for a ride and it would not stay running for long

I was thinking and thinking about it, and had an idea to check the power piston, maybe the spring is too weak and the rods are staying down in the jets

so I pulled the carb today and the spring is stretched out and the seal is super worn
https://imgur.com/QY1z28p







gonna address that, then maybe see if tweaking the APT setting

fingers crossed!


Offline Shifty

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Re: Dualjet cruising lean hesitation
« Reply #33 on: August 20, 2024, 10:11:03 am »
Good luck bro!
87 V20 Standard Cab Longbed (current)

87 R30 3+3 Longbed (days of yore)

98 C2500 ext cab longbed

Offline Scaryfastatx

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Re: Dualjet cruising lean hesitation
« Reply #34 on: August 24, 2024, 11:21:43 am »
With the new spring in the power piston, it still is dying

So after thinking a while it popped in my head to check the float level before and after it dying

In the driveway is idling and revving like a champ

So here is the float level at idle

~4.8cm (~1.88in) from float to top of the air horn, pushing down I can feel the float bob and smell the gas


So drive it around and after just a bit it dies

Here's the float level Dead on the side of the road but cranking

~5.3cm (~2.08in) from float to air horn

So definitely a fuel supply issue still going on

Right now I have 3 filters
1) long filter in the carb
2) aftermarket chrome filter on the frame rail
3) sock in the tank

I'm gonna pull the filter on the frame since it's the easiest to get to, see what that does

Then move to the filter on the carb

Then finally drop the tank and check the sock

It's a brand new tank and sock gonna be so pissed off it's the sock

Offline Shifty

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Re: Dualjet cruising lean hesitation
« Reply #35 on: August 24, 2024, 11:50:24 am »
I'd start with the one in the carb....what are the odds that it's upside-down, and the check ball is having it's way with your sanity?
87 V20 Standard Cab Longbed (current)

87 R30 3+3 Longbed (days of yore)

98 C2500 ext cab longbed

Offline Scaryfastatx

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Re: Dualjet cruising lean hesitation
« Reply #36 on: August 24, 2024, 11:56:48 am »
I'd start with the one in the carb....what are the odds that it's upside-down, and the check ball is having it's way with your sanity?

Yeah good idea
I've noticed that these new filters get rusty really fast, even with ethanol free

Wonder if that's blocking the filter too

Gotta love old vehicles!

Offline JohnnyPopper

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Re: Dualjet cruising lean hesitation
« Reply #37 on: August 26, 2024, 01:16:49 am »
Isn't the check valve/ball at the entrance of the fuel inlet?
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Scaryfastatx

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Re: Dualjet cruising lean hesitation
« Reply #38 on: August 28, 2024, 07:59:21 am »
Isn't the check valve/ball at the entrance of the fuel inlet?

yep, it has the little plastic plunger type check valve in the middle of the filter body


my gut is saying its the sock in the tank.... which Im kicking myself for not looking at it when I had it dropped earlier to replace the lines.... LIVE AND LEARN

Offline Shifty

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Re: Dualjet cruising lean hesitation
« Reply #39 on: August 28, 2024, 11:52:05 am »
Isn't the check valve/ball at the entrance of the fuel inlet?
I've seen it installed upside-down about 10% of the time.
87 V20 Standard Cab Longbed (current)

87 R30 3+3 Longbed (days of yore)

98 C2500 ext cab longbed

Offline JohnnyPopper

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Re: Dualjet cruising lean hesitation
« Reply #40 on: August 29, 2024, 06:41:47 am »
With that many filters, I'd delete the carb filter and see what happens. If still choking, delete the inline. Of course, if still choking, you will be left changing your sock, like out moms told us long ago... ::)
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Scaryfastatx

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Re: Dualjet cruising lean hesitation
« Reply #41 on: September 30, 2024, 08:56:44 am »
Ive been working on other projects, but finally got back to the truck this morning. I decided to cut open the filter to see whats going on. I dont know why I hadnt thought of it in the past, just always checked the check valve plunger to see if it would go into the filter body.

But yikes, I am really glad I checked it out




new filter is supposed to be here today.

Im guessing there is a lot of trash in the lines, all my fuel hoses are new, new tank, new sender, new pump.

Offline bd

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Re: Dualjet cruising lean hesitation
« Reply #42 on: September 30, 2024, 09:24:38 am »
Now, aren't you glad the filter did its job?   :)

Before the incorporation of check valves, you could simply blow through the filter to determine if it was plugged.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Scaryfastatx

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Re: Dualjet cruising lean hesitation
« Reply #43 on: September 30, 2024, 09:39:31 am »
Now, aren't you glad the filter did its job?   :)

Before the incorporation of check valves, you could simply blow through the filter to determine if it was plugged.

haha yep, that is exactly what I thought, I just rebuilt the carb, wouldnt have been fun cleaning out all the trash again.

Offline bd

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Re: Dualjet cruising lean hesitation
« Reply #44 on: September 30, 2024, 10:34:50 am »
It would be prudent to disconnect all of the lines and blow them out from the tank forward.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)