quadrajet secondary adjustment

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it is carb # 17085226 first pic is plug that came out with several thousand on them the second plug pic is the new plugs I had it it last time i drove it Sat. All the plugs look similar.

[bd]

Bone stock '85 c10 305 ... I had one issue with the tank selector valve that was fixed some time ago ... the hoses are good, the fuel filter is brand new, the fuel pump pumped a quart in 30 seconds....

After reviewing your opening comments and without detracting from all of the suggestions and guidance you have received thus far, did you ensure that the tank selector valve motors full rack?  When you said the hoses are good, did you verify that none are kinked or perforated?  Any chance the fuel filter behind the carburetor inlet nut is backward?  What were the fuel pump draw and pressure measurements?  What is the float level spec that you used?  What happens if you lockout the secondaries so that they cannot open and then accelerate WOT?

[bedwards]

After reviewing your opening comments and without detracting from all of the suggestions and guidance you have received thus far, did you ensure that the tank selector valve motors full rack? I tried both tanks more than once. The gauge moves, not 100% sure of the valve, but knowing how its made inside, more than likely. When it failed last time, it pumped fuel from one tank to the other and when that tank was full into the evap canister and when it was full flooded the engine through the vent. I did replace the canister at that time.

When you said the hoses are good, did you verify that none are kinked or perforated? Its metal from pump to carb, Will have to get under it to see at the fuel selector valve

Any chance the fuel filter behind the carburetor inlet nut is backward? verified, rubber end with ball towards fuel line

What were the fuel pump draw and pressure measurements? I don't know how to measure the pressure with what I have but it pumped almost a quart in 30 seconds of cranking it is the original factory pump though

What is the float level spec that you used? 13/32, it did not need moving from where it was last time I rebuilt 3 years ago

What happens if you lockout the secondaries so that they cannot open and then accelerate WOT? I will have to try this, not sure

carb kit was a GP Sorenson 96-519A from AutoZone

I am assuming that there is an electronic aux enrichment on passenger side front. It has a solenoid and what looks like a power valve underneath that it opens. All I did was clean it and put new gasket on. Not sure how to test function and there wasn't anything on how to in the instructions. I guess I could check with ohm meter to make sure there is resistance there

The carb fuel bowl was not really cruddy inside and there was no junk or water in it, but it did have a bathtub ring around it where the fuel has been.

I appreciate all your thoughts and help

[bd]

Under the circumstances, I recommend making sure that you adequately cover the basics, especially those that could manifest "suddenly" since that seems to be how the symptoms developed.  IMHO, unless the cause is obvious, only after the fundamental of adequate fuel supply to the carburetor has been substantially verified should you pursue a diagnosis, repair, alteration and fine-tuning or replacement of the carburetor.

• Rubber hoses connect the steel fuel supply line (and return line when used) to the fuel pump, the tank selector valve and the fuel tanks.  Check them all to verify that none are collapsed, kinked, split or otherwise perforated.  Be patient and wear safety goggles to keep falling debris out of your eyes.
  
  
• To check fuel pump draw and pressure you need to borrow, rent or purchase a vacuum/pressure gauge that accommodates 30 "Hg vacuum and 15+ PSI pressure.  They are available from auto parts stores for sale/rent (sometimes for free with a refundable deposit) and Harbor Freight for sale, etc.
  
  
• Try locking out the mechanical secondaries to determine whether symptoms disappear or are in fact directly related to secondary opening.
  
  
• The solenoid protruding from the top right side of the fuel bowl cover controls an accelerator pump enrichment circuit that should have no bearing on the symptoms you described.
  
  
• The 'bathtub ring' inside the fuel bowl probably reflects water contamination sometime in the past.

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Ok, will be this weekend before I can report back

thanks again

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Fuel pump is jumping from 0-5 lbs while cranking. It also does not hold pressure. Is it supposed to? Anyhow, there is a new Delphi pump on it but was too tired to finish it tonight. Will blow out the lines and get it cranked tomorrow. The lines are good and flexible, no kinks. New fuel filter too although the one in there was not 2 months old.

[bd]

The fuel pump should draw >20 "Hg and build/maintain 5-7 PSI pressure.  The pump has internal check valves that may be leaking or a ruptured diaphragm.  Drop some oil from the engine dipstick onto the tip of a clean finger.  Does the oil maintain a tight circular puddle with defined boundaries or does it quickly track out along your finger ridges?

Did you install the new Delphi fuel pump before or after posting the "0-5 lbs" measurement?

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Put the new pump on after testing the old one. I figured the pump should hold pressure. It had been hard to start cold and the choke is working. I figured its letting the fuel drain back. I'll check the oil. It hasn't made oil and it smells like oil and not like gas but will let you know.

[bedwards]

Ok, I guess I am officially one of those people (Parts re-placer)
It was the fuel pump all along. It runs really well now. It should, its got a bunch of new parts. It faked me off when it pumped a quart of fuel 30 seconds and I didn't have the gauges to check pressures then.
It wants to tink just at tip in if I go to 12 btdc so it is set at 8 right now.
Should I back off the secondary spring or leave it? It is at roughly 1 turn from just touching right now. Factory was 3/4 turn.
BD your right about starting with the basics.

Many Many thanks for all your suggestions.

[bd]

The factory secondary air valve adjustment is 7/8 turn (see my earlier post - the information was quoted from the factory service manual) so set it accordingly or leave it where it is for now.  Follow the other members' guidance if you wish to fine tune the carburetor beyond the stock configuration.

The image you posted of your new spark plugs indicates the plugs are running slightly hot.  Next tune-up, consider dropping one heat range, which may decrease the engine's sensitivity to detonation and pinging.

[ron350]

Glad you got it sorted out.

Speaking of spark plugs what is the plug in that last picture?

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It's an Accel 0566. Bought them shooting for a cooler plug. The porcelain and the tip don't go as far in as the Delco's that came out and the Delcos were one range cooler than factory specs. I am changing the oil tomorrow although it sat thick on my finger without spreading out. I did put a big plug of grease on the pump pushrod to hold it in place and hopfully the oil washed it away and I will get it out with an oil change.
tell me what you think of the plugs: