Starting up after sitting for up to 7 months?

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spitfire_er

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Just bought a 84 K10 Silverado. Previous owner wasn't mechanically inclined. Long story, I'm sure this thing has sat for at least 2-3 months maybe longer without running. I'm also fairly certain they dumped the cheapest ethanol laden fuel the could get into it.

Truck has what im assuming to be a 305 with a 4 bbl quadra jet.

For it cranking today. Dumping some fresh gas in the carb would kick it off and run good for 4-5 seconds then dies. I use to work on cars quite a bit but its been a few years. I would like tonget this thing running. I plan to pull the filter out and clean/replace. Fuel pump looks fairly new. Previous owner said it ran fine but wouldn't run good past 45mph.

Is it worth the trouble to rebuild the carb. Never done it but I can figure it out.

Any other suggestions?
 

Soundmound

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Just had the Q rebuilt on my 305. So far it's worth the juice in my opinion. I just want it drivable while I pick away at the list of fix its. If it isn't drivable, I'd probably start to lose interest and sell it for part of a house down payment.
 

CRM

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Does it have a choke?
 

fast 99

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Suggest figuring out why there is a fuel issue first. Could be a carb problem but just because it has a new pump doesn't mean it works.

Ethanol fuel should be ok for 6 months to a year. However, it will run better with E free.

Most likely if the carb has any age, it will need a rebuild. Q jets aren't particularly hard to rebuild but there are a few things to look for and do.
 

scrap--metal

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Previous owner said it ran fine but wouldn't run good past 45mph.
My K20 ran great on the test drive, but wouldn't maintain highway speed on the drive home. Filling the gas tank washed all the loose rust into the fuel and it plugged up the fuel filter twice on the drive home.

You have the right idea starting with the fuel filter. Good luck!

If the filter looks clean while you have it apart, verify that the fuel pump is working. Have someone bump the key to turn the engine over while you hold the fuel line over an appropriate container. It should burp a good gush of fuel every time the arm in the fuel pump moves.
 

CRM

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Have you checked choke operation, and voltage?
 

Camar068

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clogged screen on sender? Put that pump line into a bucket, milk jug of gas to half split troubleshoot it. Or even better drop the tank a bit, pull the line and put it in the jug. Pick your poison spot to start.
 

spitfire_er

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Today, I pulled the filter and it looked pretty bad inside. Grey/white gunk. I think this could explain the poor power and bad power on the highway. Got it hooked up again and still no gas, took the carb apart, a little dirty, but looked OK and pump was squirting fuel on the primaries. Put it all back together... nothing.

Pulled the main fuel line, No fuel. This is after I checked it before all of this and it was pumping.

I'm thinking now, the tank is empty and not sure if the fuel gauge works. I will add a couple gallons tomorrow and see what that does. Ill have to play the fuel tank lottery and just go with the one its currently switched to which is the right side.

If thats the problem, my $1,000 truck, will have taken $17 to get running. Not including the $140 battery and the $65 starter(that I probably didn't need at this time).

If I have gas in the tank and still no fuel, I'll replace the fuel pump.
 

spitfire_er

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Well, after trying to fill up the drivers side tank and realizing it was very full, I figured out how to make the tank switch in the cab work. Went from the completely empty passengers side tank to the completely full drivers side tank. Been many years since I saw the needle move that fast when switching tanks. At least the switch and fuel gauge works.

Cranked for about 5 seconds and fired right up. Idled fast till it warmed up then kicked the pedal and dropped down to an idle.

Now, the next thing. Ill just start a build thread..... it won't end till I rebuild the entire truck it seems.
 

spitfire_er

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I don't think I have time for a build thread and not sure I'll even do that much to it.

I got it running, pretty good actually, but two issues. First the trans shifts hard out if 1st and the engine RPMs are really high when it kicks into 2nd.

Main issue though is I am getting a knocking noise, almost sounds like a diesel. It's there all the time and worse with higher RPMs.

I compression tested all cylinders and they all run 150-170 psi. #1 cylinder has a badly fouled and oil covered spark plug. The others look fine. Not sure what the problem is, but getting smoke of course from that side of the exhaust.

I'm not sure what causes this, but I don't think it's in my wheelhouse to repair. Any ideas?
 

Scott91370

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Sounds like the detent cable needs to be adjusted (if your model has it) to get it to shift earlier.
 

Frankenchevy

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Which transmission do you have?
 

newguy11

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Today, I pulled the filter and it looked pretty bad inside. Grey/white gunk. I think this could explain the poor power and bad power on the highway. Got it hooked up again and still no gas, took the carb apart, a little dirty, but looked OK and pump was squirting fuel on the primaries. Put it all back together... nothing.

Pulled the main fuel line, No fuel. This is after I checked it before all of this and it was pumping.

I'm thinking now, the tank is empty and not sure if the fuel gauge works. I will add a couple gallons tomorrow and see what that does. Ill have to play the fuel tank lottery and just go with the one its currently switched to which is the right side.

If thats the problem, my $1,000 truck, will have taken $17 to get running. Not including the $140 battery and the $65 starter(that I probably didn't need at this time).

If I have gas in the tank and still no fuel, I'll replace the fuel pump.
That’s some politician math right there. 17 + 140 + 65 = $17!

I joke I joke, glad you got your rig in good working order. For what it’s worth I rebuilt my quadrajet this year with a kit from quadrajet power ($40 I think) and I made a world of difference.
 

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