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Old 06-19-2012, 11:31 AM   #16
MarkO
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Default Re: Carb Sputtering issue

I will chime in here but will admit up front that I am no kind of expert.

Stumbling from a stop is the result of one of two things--either a lack of gas or too much air. Lack of the former makes a surplus of the latter. If you have a surplus of the latter you will have a lack of the former.

To attack the problem you have to discover what it is you have too much of or what it is you lack.

In most cases, too much air is due to a vacuum leak somewhere in the system. Vacuum hoses, vacuum accessories, carb mount, cracks in the throttle plate, and a loose throttle shaft are all areas in which excess air can be introduced to the system.

In most cases, too little fuel is due to a problem in the carb itself. Not enough stroke on the throttle pump, dirty passages, faulty power valve, low float level, etc. It could also be a lack of volume from the fuel pump, an issue I recently had (the symptoms were lack of power and sputtering under load).

The only way in which to determine what is causing the problems is you need to go about the diagnosis in a step-by-step order so that you can eliminate issues before you start throwing $$$ at new parts that most likely don't need replacing.

Eliminating issues that don't cost any $$$ is better than spending a lot of $$$ only to discover later that the cause of the problem was a no-dollar fix.

Good luck.
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Old 06-19-2012, 02:35 PM   #17
Scoutboy74
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Default Re: Carb Sputtering issue

A couple more thoughts since this problem seems to be temperature related. A vacuum leak, while certainly still a possibility, is generally problematic whether the engine is hot or cold. One additional thing to check is choke function. A partially applied choke will create performance issues on a warm engine. The choke plate must be able to close and open fully without binding up. If automatic, it should be fully open after 5 mins of run time. If manual, verify that a fully pushed in knob is opening the plate all the way. If this is a 2300 modular model, there should be an approximately 1/4 thick Holley or felpro base gasket in place which includes a fuel bowl heat shield. Fuel percolation from engine heat is most problematic at idle and part throttle situations.
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Old 06-19-2012, 06:00 PM   #18
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Default Re: Carb Sputtering issue

So everybody seems to tell me that it's either a vacuum leak, lack of fuel, and/or a choke issue. Scoutboy74 I have a automatic choke. Also scoutboy74 here is the carb info you wanted.
R 7214 a
465529 c91
0968
I don't know if that in what you were looking for but it's the only numbers on the carb. Marko and fdchappie I have replaced all the vacuum lines with new ones. Just wondering, but if I were to hook up the vacuum lines in the wrong place could that cause this sputtering issue?
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Old 06-19-2012, 09:20 PM   #19
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Default Re: Carb Sputtering issue

Those numbers identify it as a 2210, which would be a direct replacement of the stock unit. I'm not a huge fan of this model. They can be dealt with, but they're often more trouble than they're worth. The quality of reman parts, especially carbs is not what it once was. Media blasting, shoddy service parts and incorrect gaskets are the norm. I'm not saying throw the thing in the trash. It might be fine and hopefully it is. These are just things for you to be aware of. It's too bad the friend doing all the urging didn't suggest a brand new Holley list 0-7448 2300 as a replacement. That would be a legitimate upgrade.

So it has auto choke, but have you actually watched the choke plate movement from a cold start with the filter canister out of the way? If not, you should. Your problem could be as simple as a choke that's out of adjustment.

Yes, incorrect routing of the vacuum lines could cause performance issues.
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Coal Trickle - '99 Dodge Ram SLT 2500 Q-Cab SWB 4x4 - 5.9L 24V CTD/NV4500/8800# GVW/12K# winch
Hooty - '74 SII 4x4 - 392/TF727/D20/3.73 D44's/Spartan FA/Powr-lok RA/33g Fuel
Lemuel - '73 1210 Reg Cab 4x4 CS - 304/TF727/NP205/4.09 FA25 & 4.10 RA16/6800# GVW - "Pull Lemuel, pull!"
Organ Donor - '72 1210 Reg Cab 2WD - seized 392/TF727/7500# GVW - "Use my body to keep you alive!"
Mongo - '71 1210 Reg Cab 2WD - 345/TF727/4.10 RA17/6100# GVW - "Mongo love candy! Duh, huh, huh!"
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Old 06-20-2012, 07:04 AM   #20
cropro27
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Default Re: Carb Sputtering issue

Scoutboy74 let me ask you this. Could you rebuild the 2210 by using a 2300 rebuild kit? If I can't then what can I do to deal with this lack luster model? Also where would be a good place to find a vacuum hose diagram for a 76 304 terra?

Well its kinda hard to drive with the hood up and really see whats going on. So no I haven't delt with my issue that way, but I have had the engine running with the hood up and the canister out of the way. It works fine but im not mechanic. So I'm not sure if what I perceive as normal is normal.
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Old 06-20-2012, 08:30 AM   #21
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Default Re: Carb Sputtering issue

Not to say the carb is not the issue but do a real simple check of both the mechanical and vacuum advance and make sure they are both properly working. Either one can cause a sputter or hesitation upon acceleration and both are very easily checked. Once you have confirmed that the distributor mechanical advance is not stuck or sticking and the vacuum advance is holding a vacuum then I would move onto the carb.
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Old 06-20-2012, 08:41 AM   #22
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Default Re: Carb Sputtering issue

No, you can't cross-mojinate between the 2300 and 2210 models. They don't share any parts in common, as they are a completely different style of carb, though they are both made by Holley. Your approach to diagnosing the root cause of the issue should still be centered on ruling out simple causes first.

Obviously, you cannot monitor choke function while driving. That would be difficult and unsafe even if the hood were removed. You watch it while idling parked in your garage or driveway when you have 5-10 minutes of free time to dedicate to the process. I more or less described normal function in one of my previous posts, but I'll provide some additional description. When the engine is cold, one stab of the throttle should set the choke plate closed nearly all the way. When you engage the starter, the engine should light off within a few starter cranks and rapidly race up to a fast idle speed of approximately 1600 rpms +/- 100. This increased speed is necessary to help keep the cold engine running. As the thermal spring inside the choke mechanism warms, it begins to pull on the linkage rod, which in turn gradually begins to open the choke plate, while engine speed also gradually drops. After roughly 5 minutes of run time give or take, the choke plate should be viewed as fully perpendicular inside the air horn opening, with an equivalent air gap on either side of the plate. Engine speed should have also settled to a curb idle of roughly 650 rpms by this time. If you need assistance determining what's going on and you have access to a digital camera, you can post a pic of the choke plate just prior to starter engagement along with another after the engine has warmed. Pictures aid the cyber-diagnostic process greatly. In many cases they are a necessity.

The best source for a vacuum diagram would be found in a service manual for your Scout. They are available for purchase via the IH Parts America online store. If you plan on owning and tinkering on a Scout for any real length of time, it is a valuable resource to have available. In the mean time, if you are desperate with no recourse, I can scan and attach the diagram from a '74, which should have close enough if not identical vacuum hose routing as it deals with the same carb model.
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Coal Trickle - '99 Dodge Ram SLT 2500 Q-Cab SWB 4x4 - 5.9L 24V CTD/NV4500/8800# GVW/12K# winch
Hooty - '74 SII 4x4 - 392/TF727/D20/3.73 D44's/Spartan FA/Powr-lok RA/33g Fuel
Lemuel - '73 1210 Reg Cab 4x4 CS - 304/TF727/NP205/4.09 FA25 & 4.10 RA16/6800# GVW - "Pull Lemuel, pull!"
Organ Donor - '72 1210 Reg Cab 2WD - seized 392/TF727/7500# GVW - "Use my body to keep you alive!"
Mongo - '71 1210 Reg Cab 2WD - 345/TF727/4.10 RA17/6100# GVW - "Mongo love candy! Duh, huh, huh!"
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Old 06-20-2012, 09:17 AM   #23
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Default Re: Carb Sputtering issue

Yes hooking the hoses up incorrectly could cause the problem. Try plugging of the egr hose and running it to see if that resolves the problem. The egr is the round device located behind and to the right of the carburetor on the intake manifold. Then try hooking the distributor vacuum advance unit directly to ported vacuum that should be located on the front of the carb near the bottom.
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Old 06-20-2012, 12:02 PM   #24
cropro27
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Default Re: Carb Sputtering issue

Scoutboy74 the choke plate does completely flatten out before I start the engine. After the 5 or so minutes the choke plate does open but not all the way open. It probably opens to about 60% to 70%. It doesn't open fully vertical.

Now say I have checked all the vacuum, choke, and any other things that might be causing this problem. What else could the issue be if those other things check you to be ok?
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Old 06-20-2012, 01:10 PM   #25
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Default Re: Carb Sputtering issue

Sounds like it isn't opening all the way. Just to be sure, I'd like you to look at it again after you've gone for a drive and gotten the engine good and hot. Pop that canister off and see if it hasn't opened any further. If not, an adjustment needs to be made so that it will open fully. I think you've been given to verify and rule out for now. We can cross the "what if" bridge when/if we come to it.

One thing we should do is make proper id of your distributor. Originally, a '76 would have a Holley electronic ignition with remote module, more commonly referred to as a gold box due to the common color of the nodule which would be located on your driver side firewall. But, just in case someone has swapped in something else along the way, such as a points distributor it would be good to know. It always helps to have as much information about the components in play as possible. These rigs aren't all the same and parts do get swapped around like rockers swap girlfriends.
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Coal Trickle - '99 Dodge Ram SLT 2500 Q-Cab SWB 4x4 - 5.9L 24V CTD/NV4500/8800# GVW/12K# winch
Hooty - '74 SII 4x4 - 392/TF727/D20/3.73 D44's/Spartan FA/Powr-lok RA/33g Fuel
Lemuel - '73 1210 Reg Cab 4x4 CS - 304/TF727/NP205/4.09 FA25 & 4.10 RA16/6800# GVW - "Pull Lemuel, pull!"
Organ Donor - '72 1210 Reg Cab 2WD - seized 392/TF727/7500# GVW - "Use my body to keep you alive!"
Mongo - '71 1210 Reg Cab 2WD - 345/TF727/4.10 RA17/6100# GVW - "Mongo love candy! Duh, huh, huh!"
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Old 06-20-2012, 02:33 PM   #26
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Default Re: Carb Sputtering issue

I ran the truck for about 20 to 30 minutes mostly at 55mph and higher. The bad news is that the choke valve didn't open any more then what I last told you.

I do have electronic ignition. I have replaced that gold box, distributor cap, plug wires, and the ignition coil over the years. I have been coming to believe that it might be the egr valve. It's the original one that was installed in 1976.
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Old 06-20-2012, 02:48 PM   #27
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Default Re: Carb Sputtering issue

What's the benifits and disadvantages of using a egr block off plate? If I installed one of those would that stop that sputtering issue?
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Old 06-21-2012, 08:00 AM   #28
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Default Re: Carb Sputtering issue

Well, the choke not opening fully May not be thee Problem, but it is a Problem that needs to be addressed. At best it is creating a low air to fuel ratio at cruise which hurts your mpg's. At worst it is making the engine fart and stumble too. If this thing is no longer subject to smog certification, I wouldn't hesitate to delete that egr and cap off the vac line. The only purpose that item serves is emissions management.
When you replaced the cap and plug wires, you were very careful in your wire routing, yes? Two wires where they ain't 'sposed ta be can give ya all kinds of headaches.
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Coal Trickle - '99 Dodge Ram SLT 2500 Q-Cab SWB 4x4 - 5.9L 24V CTD/NV4500/8800# GVW/12K# winch
Hooty - '74 SII 4x4 - 392/TF727/D20/3.73 D44's/Spartan FA/Powr-lok RA/33g Fuel
Lemuel - '73 1210 Reg Cab 4x4 CS - 304/TF727/NP205/4.09 FA25 & 4.10 RA16/6800# GVW - "Pull Lemuel, pull!"
Organ Donor - '72 1210 Reg Cab 2WD - seized 392/TF727/7500# GVW - "Use my body to keep you alive!"
Mongo - '71 1210 Reg Cab 2WD - 345/TF727/4.10 RA17/6100# GVW - "Mongo love candy! Duh, huh, huh!"
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Old 06-21-2012, 09:34 AM   #29
cropro27
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Default Re: Carb Sputtering issue

Ok so it seems like we have deduced that it's probably the choke not opening all the way. I hope that all it is. I was a little worried that it might be a compression thing. When I replaced the cap and plug wires I took off and replaced each wire one at at time.

I want to thank you and the others who helped me hopefully take care of this problem. If not then I will keep working at it. At least now I have a direction. So again thank you and until the next minor issue.
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Old 06-21-2012, 12:19 PM   #30
Scoutboy74
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Default Re: Carb Sputtering issue

Might be jumping to a conclusion. No doubt your engine will be happier with a choke that can open fully when the engine is warm, regardless of whether or not the sputtering is gone. There were good leads suggested by others that are still worth pursuing. That's what we're here for. Most of us have had to deal with our fair share of vehicular issues. Please follow up with your results after you've adjusted the choke and gone for a drive.
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Coal Trickle - '99 Dodge Ram SLT 2500 Q-Cab SWB 4x4 - 5.9L 24V CTD/NV4500/8800# GVW/12K# winch
Hooty - '74 SII 4x4 - 392/TF727/D20/3.73 D44's/Spartan FA/Powr-lok RA/33g Fuel
Lemuel - '73 1210 Reg Cab 4x4 CS - 304/TF727/NP205/4.09 FA25 & 4.10 RA16/6800# GVW - "Pull Lemuel, pull!"
Organ Donor - '72 1210 Reg Cab 2WD - seized 392/TF727/7500# GVW - "Use my body to keep you alive!"
Mongo - '71 1210 Reg Cab 2WD - 345/TF727/4.10 RA17/6100# GVW - "Mongo love candy! Duh, huh, huh!"
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