Progress, some questions.

[ungoliant]

Okay so I got to tinkering with my Scout some more, I've been having some idling issues.

It was stalling out shortly after starting, but I adjusted the idle screw on my carburetor a bit, and it starts up and idles fine.

However, now the engine tries to die on me when I put it into drive or reverse. If I give it gas, it takes off and drives just fine, but if I sit still with my foot on the brakes (like at a red light) it'll die on me unless I give it gas or put it in park.

I'm open to suggestions. Been a while since I tinkered with carburetors or domestic vehicles.

Also, what kind of carburetor do I have? I know it's an edelbrock, but that's it.

 

[Michael Mayben]

Your carburetor is not an edelbrock. It is a carter afb that has been swapped on, ihc did not use carter carburetors on any sv engine oem.

An edlebrock "performer" series carburetor is a clone of the original carter afb and manufactured under license by marelli. An edelbrock "thunder" mixer is likewise a clone of a carter avs unit, those were a more sophisticated/evolved design of the "air valve secondary" carbs.

The only identification regarding exactly which version it is is the number stamped into the passenger side front mount pad. Same holds true for the edelbrock clones.

That carburetor is in dire need of a complete rebuild. And while it's off, all vacuum hoses and connections need some major attention, as well as replacement of the base gasket with a proper gasket for that carb. The carter afb while having the so-called "squarebore" bolt mount pattern, is not a true squarebore carburetor that was designed to bolt to that oem manifold so the gasket must be carefully selected for match or a major vacuum leak will result.

 

[ungoliant]

Don't get me wrong, I'm just curious: what is the indicator to you that the carb needs a rebuild?

Also, what goes into rebuilding one?

And lastly, where would I find a proper gasket?

 

[Michael Mayben]

don't get me wrong, I'm just curious: what is the indicator to you that the carb needs a rebuild?

Also, what goes into rebuilding one?

And lastly, where would I find a proper gasket?

Clues??? 50 years of experience doing this shit!

The outside is filthy and somewhat jury-rigged. The inside will look even worse due to moisture accumulation over the years due to neglect of maintenance, those carbs are aluminum and corrode like hell internally in the presence of accumulating moisture. I have three of 'em now on the bench that would better serve as scrap parts donors but the owners want 'em rebuilt though cosmetically they will look like shit. Moisture-induced corrosion internally is death for carter afb/edelbrock clones.

Also I know your accelerator pump system is dead (or dying), same thing, lack of maintenance, adjusting won't fix a dead accel pump element.

The e10 fuel that your government has forced you to burn is a carburetor killer. It sucks up moisture like a rag mop, the alcohol component eats some of the metals inside that mixer. You should see what it does to brass floats! When we're forced into the currently-evolving e15 shit, you can park your Scout and just look at it, ya won't be able to drive it unless you are a professional mechanic from the old skool like me!

In my world of carburetor service, a carb has an active service life in daily use of two years, then it needs to be rebuilt, that is part of the never-ending cycle called preventative maintenance.

 

[ungoliant]

I wasn't trying to say you're wrong, I was just curious what your rationale was so I can understand a bit better.


So how is it jerry rigged, exactly? What do I need to fix to make it the way it's supposed to be?

 

[Michael Mayben]

I wasn't trying to say you're wrong, I was just curious what your rationale was so I can understand a bit better.


So how is it jerry rigged, exactly? What do I need to fix to make it the way it's supposed to be?

Juryrig---the fuel inlet plumbing is a disaster waiting to go up in flames. Someone has po'd the divorced choke thermostat/actuator to a carb that was never intended to use a divorced choke mounted that way (from the pic I can't tell if it's actually connected or not). The air cleaner is not sealing the air horn, all that garbage on the clean side of the air horn has gone through the combustion chambers of your engine, might as well leave the air cleaner off. Looks also like the throttle lever and linkage is fudged somewhat.

Also...every piece of vacuum-related rubber under the hood appears to be rotten, that means many vacuum leak points that all add up. And most likely the egr valve is non-functional and needs to be cleaned and tested, and the egr ports in the intake manifold plenum need attention also, I bet they are totally clogged shut and carbon chunks are being drawn through the intake manifold.

When stuff like comes into my shop, everything gets pulled off and dumped in the recycle pile. Then the carb gets completely reconditioned and tested. Once the carb is re-mounted, then all the vacuum-related items are re-plumbed with fresh material.

Then the ignition system gets the freshening operation also before the engine is started for tuning. Once that is out of the way the carb is dialed in for idle mixture after verifying proper choke operation and "pull-off".

Once the carb is 100%, then the air cleaner system is checked for dirty air bypass and repaired as needed. Then a fresh fuel filter (or two) are installed and yore done.

What you have is a typical piece of old iron being brought back to life that has been sorely neglected for years...we deal with these exact same vehicles issues 24/7 around here! I'm doing one right now that while it is essentially a virgin under the hood and had over $10k spent on it in 1987/88, it has not been run or even moved since 1990.

If you post some nice, well-focused and lit, medium shots of the engine from several angles I can pick your motor apart like a buzzard, then you will know what needs attention!

 

[ungoliant]

Pictures will be coming during this weekend. There's a bunch of wires that aren't connected to anything, some hoses that aren't either. It's kind of a nightmare, but I got a service manual, so hopefully that will help with some of it.

I'm fairly experienced with engines, but I lack experience with carburetors and I'm not terribly good at diagnosis, but I'm decent at guessing (though I don't like that method).

And to give you an idea of the history of this vehicle, the guy who I got it from had 5 scouts until someone else and myself each bought one. The one I have he used to use as a daily driver, however he hasn't run it over a large portion over the last year or so. I received it maybe a week or two after it's been running again.

Anyhow, could you point me to a couple things:

1. A diagram showing where the parts you listed are? I.e., the pcv valve, air horn, egr valve, egr ports, etc.

2. What a proper setup of this carburetor is supposed to look like since it's not a stock carburetor, and where to get a rebuild kit for it.

Also, I think it is an edelbrock performer 1405 (I'm pretty sure, the numbers were kinda hard to see).

 

[Michael Mayben]

Good detail!

So your situation regarding your project is no different from the majority of other folks around here who have faced/are facing the same exact scenario! That's what makes this stuff projects and not life it'sownself!

I believe all of your current questions are addressed in the various sub-forums here if you will take some time to scan through each and every thread. You are going to find vacuum routing diagrams, electrical schematics, tons of pics (many of which are far worse than yours!!). Once you post your pics we can get down to the business of correcting/upgrading all the typical lack-of-maintenance points ya got. Once that is out of the way, then ya can move on to dealing with all the other issues you will have. Take this stuff in stages, concentrating on a systems-basis. If ya shot-gun it you will chase your tail forever trying to diagnose/repair secondary issues that are not root cause!

And if you have the service manual, you will find all diagrams needed in the book, though it will take some careful concentration to figure out that stuff, there are several variations of vacuum routing dependent upon if the vehicle was originally a 49 state unit or kalifornikate emissions only. Same for testing/servicing the egr system if still functional.

If in fact the numbers 1405 are stamped on that carb, then it is indeed an edelbrock clone. It looks like someone has "activated" the vent on that bowl cover to connect to the charcoal canister component of the evaporative emissions system (a smog-related system). So I stand corrected...now you know what ya have, that is the first step in dealing with this stuff!

The 1405 number denotes a manual choke version, thus it has been somehow connected to the oem divorced choke thermostat on your engine, without clear shots of that hookup, we can't tell if it's currently operating or not. And since the edelbrock does not provide a "choke pull-off" component, the correct operation of a divorced choke on that install is gonna be less than desirable and May well be part of your overall issues.

There is only one carburetor kit for the edelbrock performer series mixers. Those are available everywhere. Go to the edelbrock website and do some research including downloading the significant tuning guide for that carb.

A correct base gasket to mount that carb on the ihc 4v manifold is going to require a bit of gasket fabrication. You will need a Holley-type squarebore base gasket with the smallest throttle plate openings that you will carefully hand cut to match the edelbrock throttle body.

Those carburetors are designed for a completely different design manifold base/plenum that does not use the "four round hole" pattern that makes the slang term "squarebore" so popular. That is why edelbrock supplies that thin steel transition plate with those mixers when purchased new. I can't tell from the pic whether yours has that plate or not. I'm not saying you must use it or will not use it. I need to see the top of the mounting flange for your manifold in order to make a call about that as these intake manifolds on the sv motors are not "all the same".

 

[ungoliant]

The divorce choke isn't hooked up to the carburetor, it's just been disconnected and left in place.

 

[ungoliant]

Well I replaced all the vacuum lines and swapped some around to where they're supposed to be, and it's running about twice as good as it was.

Still has a bit of trouble, but now I've noticed transmission trouble.

So we'll see where I get with it in the next month or so.