1986 Jimmy 5.7 Fuel Issues and De-Smogging

[Tankr]

I recently purchased a 1986 Jimmy 5.7 w/ SM465 in nearly original condition w/ all factory SMOG system 100% in intact and original CCC Q-Jet, air cleaner, cold air hose etc.. I am having fuel issues @ carb as it will not start w/o manual priming. I am worries that well plugs are leaking however i plan to make pulling carb a last resort as it runs perfectly after finally starting! After getting running this weekend the fuel pump began to leak from weeps therefore i plan to replace. While trouble shooting I began checking wiring and found that sensor in t-stat housing w/ wire going to carb had broken spade, see embedded image. In order to replace fuel pump i have to remove smog pump for access purposes. That being said i would like to go ahead and remove all SMOG equipment from the truck and plug ports in manifolds. I have 3 questions.

1. What is the GM part number and or proper description of this sensor?
2. Will my CCC Q-Jet run properly after de-smogging? If not, what needs to be done to run correctly
3. Does anyone have any suggestions for de-smogging and or references to previous threads for how to? I do not want to cut the wrong stuff out or remove vacuum lines that I may need...

Any help would be greatly appreciated.

 

[Wes Harden]

Pictures aren't showing for me.
Removing air system will not effect ccc, it may effect how long the catalytic converter lasts, if you keep. Egr is ok to go as well. Keep the evap system, and make sure the map sensor has good solid vacuum signal.
The sensor near the Tstat is probably the ect ( engine coolant temp).

 

[diesel4me]

I'd avoid deleting all the smog equipment--it won't run any better without it ,maybe worse,and in the future you may need to have it all intact & working to get the truck to pass an emission test--not all areas will remain "smog test exempt" in the future,when the feds decide to start culling old vehicles labeled "gross polluters"..

If you just dont care,go ahead and take it all off,plug off the A.I.R. ports in the exhaust manifold,and you could sell off all the stuff to someone in CA who cannot register a old vehicle with missing emission parts..

You may suffer carb icing if you get damp chilly days under 50 degrees without the hot air stove air cleaner setup installed and working..it also reduces the time required to warm up from a cold start,which can improve gas mileage..

Your fuel pump diaphragm may be ruptured if gas is coming out of the casting's "weep hole" or around the crimped can that houses it--that can let fuel siphon back to the tank or to where the leak is and empty the float bowl,so you'll need to crank it over a long time or prime it to get it running--gas can get in the crankcase when a mechanical fuel pump fails,so changing the oil right away is a must..

Pictures not working for me either...

 

[muddermilitia]

He's a new member. There is a required amount of posts before he can post pictures. I forgot what the post limit is

 

[frankin5]

5 posts

 

[dyeager535]

Removing EGR will cause it to run lean (edit: under part throttle. You will feel it surge). I suggest not monkeying with anything more than necessary to keep it running. "Improving" things usually results in unintended consequences. And I hate carbs, the CCC system being among the worst.

The only way I'd screw with it, is to yank everything, and drop TBI in there.

 

[imiceman44]

Removing EGR will cause it to run lean. I suggest not monkeying with anything more than necessary to keep it running. "Improving" things usually results in unintended consequences. And I hate carbs, the CCC system being among the worst.

The only way I'd screw with it, is to yank everything, and drop TBI in there.

I second this