Chevy Kodiak dumptruck gasoline problems

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Yup. But first, remove the contaminated gasoline from the tank, pump and lines. Safest would be to remove the gas tank and have it de-rusted, cleaned and lined.

--Winston

We did this, thanks.

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After two years of setting dry and unattended, I'd guess the carb float is at best stuck and other issues as well. I'm thinking these would still have a manual accelerator pump as well.

All in all, a good carb cleaning and perhaps a kit are likely called for...

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Clogged bronze filter at the carb gas line inlet?

jsw

Jim, where is the filter that you have in mind? On the carb itself?

Like I said, I did disconnect the gas line where it enters the carb, and fuel came out of the disconnected line when the fuel pump is activated.

So, if you mean a clogged filter in the carburetor, I guess it is possible, but if you mean some inline filter on the lines leading to the carburetor, I do not think that it is possible.

i i

Onboard computer bad ? Check fuel line pressure ?

Looks like throttle body injection (TBI), lots of stuff to go wrong.

Best Regards Tom.

Yes, if it is TBI it does not have a carburetor, it has a throttle body which only superficially looks like a carb. The TBI setup has an in-tank high(er) pressure fuel pump and two fuel injectors in the throttle body. You can check to see if the injectors are being opened by the PCM with "NOID" lights which you can usually borrow from an auto parts place (with deposit). If the injectors are getting driven by the PCM they may well be clogged/stuck, I don't believe a set of those injectors is all that expensive. If they are not getting driven by the PCM there could be issues with sensors like crankshaft or camshaft position.

What model year is it? I had a 1990 FS Blazer with the TBI 350 and the TBI 454 was an option. I *think* I still have the manuals for it around.

dpb, here's where I am lost.

The carburetor, visibly, does NOT have a bowl. It does, however, have those electric valves on top. It might have a bowl, but its location is not obvious or visible.

OK... will do ...

This does seem to be TBI (not that I know much) and the engine is a Chevy 454!

If you have anything on it, I would love to get a copy or a scan!

Thanks a lot!

This is what the TBI unit looks like on the 1990 vintage 7.4/454:

Almost certainly it is the TBI - Throttle Body Injection - early fuel injection setup.

Looks like this:

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My thoughts exactly.

Start with something easy - check the ECM fuse.

This link is wrong.

On 2/14/2012 7:14 PM, Ignoramus10095 wrote: ...

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I hadn't looked at the closeup pictures before, but just did after thinking about the year. It's one of the hybrid injection systems. I've had a couple but never had to work on one so forget the earlier thoughts posted--they're not pertinent to these.

I think the phrase is "throttle body injection" for looking for information.

If I were to hazard a complete guess, it would be after two years idle the injectors are plugged. How to attack them, specifically, I don't know, sorry.

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Ignore it...

--what you have in the picture there is throttle body fuel injection and not a carburetor.

. Except it is not a carb. You have a TBI engine - throttle body injected. What year is the puppy? If it is pre-1996 a good code scanner can tell you everything you need to know, if you know what you need to know - if you know what I mean.

The two "solenoids" are fuel injectors - and the other part - the metal hat with the adjuster screw in it is the fuel pressure regulator. See if the connection to one injector has 12 volts on one side any time the key is on and it a 12 volt lamp (test light, noid light, or 194 side marker lamp in socket) connected across the connector flashes when the engine is turned over. If you have 12 volts and the light flashes the injectors or regulator are likely the problem. If not, you have electrical problems. Ther will be a "shrader valve" somewhere on the fuel line. You need to verify your fuel pressure. It should be roughly 10-12 PSI if my memory serves correctly.

If it is pre 1996 you can get the trouble codes off the check engine light by shorting terminal A to B on the aldl connector. That's the two end terminals of the top row on the right side.

You should get a code 12 - flash - - flash flash.

Look for a code 33 or 34 (map sensor), 54 (fuel pump circuit) 55 (bad ECM) 21 or 22 (throttle position switch), or 14 or 15 (intake air temp sensor) Any other codes should not prevent it from starting. Also be sure you ARE getting spark. No spark usually means no trigger for the injectors as well.

A somple injector function test is a stethoscope - you should hear them go "tick-tick" when the engine is cranked.