Cleaning Carburators? Tech Question
 

I have an old 93 isuzu pickup that I bought 2 years ago for $500. It is so nice to have a beater POS that I can beat to hell. (I have another car and a motorcycle for more reliable transportation). It has 197k miles on it, and was running good until this week.

When it is warm, it seems to totally lose power - it is NOT a misfire issue (I have a great general knowledge of cars, and have built and replaced engines myself - but only really have tech knowledge of FI cars). I thought I was totally losing compression since it has so many original miles and really felt like it was losing power. But today I did a compression test and the results were 150psi across the board +/- 5 psi which is well within spec.

Upon inspecting the carbs, it looks like on one of the barrels (its a two barrel) the butterfly valve for the choke (i think) doesnt seem to be doing anything. It has no spring resistance to it - meaning that if I flip it to one side, it just stays there. I am thinking that this could be the problem. Maybe the valve is flapping around and choking the engine? Does it sound possible?

And if so, would cleaning the carbs help? I don't want to just spray carb cleaner in there, but would rather remove them and fully clean them.

Any advice on this? Also - I have a Chiltons manual - but they are pretty half-ass. But at least it give me torque specs and stuff, but little about cleaning the carbs.

Just figured with the amount of people on this board, someone has done this at least a few times before.

If its a beater, why not try a simple, cheap, quick fix like carb. cleaner first. Unless its not a beater. . .

If I recall correctly, the butterfly valve should be attached to a rod that activates it. Sounds like the spring or actuater is shot or missing. If that is the case, you may have a few solutions, like trying to replace it with a new spring, or rebuilt carb al together.

I have seen people who have gone so far as to rig a manual choke with something as "cheap" and "simple" as parts gotten from a bike shop.

It is definately a beater. I had some carb cleaner, but the can was almost empty and just sorta sputtered. I will try to get a new can this weekend - I need a new air filter as well.

Thats what I was thinking too. I dont know how the choke butterfly is suposed to be activated normaly, but it doesnt seem to be working regardless. I will try to take the carbs off this weekend and have a look.

The bicycle rig job sounds like something I would do. I like that tip!

Well, I think I figured out part of my problem. I spent some time working on the carbs today, and after removing some parts I found this:

The Carb



Here is a pic after I removed it:

The Problem

Crazy. I have had the car for a while, and never knew. The guy who had it before me must have dropped it in there. Needless to say it runs a lot better now.

Don't you just love simple fixes?

I can safely say: don't use carburetor cleaner to dissolve the glue that holds on your devil horns that are part of your Halloween costume.

Freakin' OW.

Actually, hell yea. I was thinking that same thing after I got it out. I wish all car problems were that visually obivous. Newer cars have so many damn sensors and are completely inoperable without their computers it takes forever to diagnose problems. I'll take a bolt in the carb anyday over a short in an electrical system. :D





It took me about three reads of your post to figure out what the hell you were talking about. Then I laughed my ass off. :lol: Thanks for the tip!

I'm here to help.