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  #16 (permalink)  
Old 12-28-2010, 09:35 AM
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@ Cyclops: The sparkplugs were gapped to 0.060 for California emissions. But since some of the emissions stuff is missing, .045 may be the way to go. And don't worry about the sides. I know what you meant

@ T-Bucket: That was my mistake for not providing the right information on the igntion system. Sorry




Just so everyone can see what I'm working on, here are some pictures.


Engine Bay:




Distributor Cap and Coil:





Carb - Front View:





Carb - Top View:




Carb - Passenger Side View:





Carb - Driver Side View:




Fuel Filters by the Right-Side Tank:

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  #17 (permalink)  
Old 12-28-2010, 09:43 AM
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Wow! You don't have the canister for adjusting the choke. Hopefully somebody better with Quadrajet carbs can help out on this one. I've had one with a similar choke setup and ended up eliminating it and went to a manual choke with a cable at the dash. The two steele canisters with the hoses to them should hold vacuum. Unhook the hoses from them and push the plunger in on one, put your finger over the end of the hose or fitting on it and see if it holds the plunger down, a minute for each ought to be sufficient. If it lets the plunger back up while you have the port covered, it is not acting as a choke pull off which would open the choke or close it which I'm assuming one of the two does.
Good luck and I'll keep checking this thread as it updates,
Chip.
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Old 12-28-2010, 10:18 AM
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Looking back at the picture, I see only one canister. Test it like I said and suck on the hose to it to see if it pulls the choke open or closed. I'm thinking the choke closes at the application of throttle prior to starting it and that'll lead to a choking problem. If that is a choke pull off and it won't hold vacuum, it'll stay choked. I'd think most any parts store would have it in stock.
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  #19 (permalink)  
Old 12-28-2010, 12:09 PM
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Quote:
Originally Posted by cyclopsblown34
Wow! You don't have the canister for adjusting the choke. Hopefully somebody better with Quadrajet carbs can help out on this one. I've had one with a similar choke setup and ended up eliminating it and went to a manual choke with a cable at the dash. The two steele canisters with the hoses to them should hold vacuum. Unhook the hoses from them and push the plunger in on one, put your finger over the end of the hose or fitting on it and see if it holds the plunger down, a minute for each ought to be sufficient. If it lets the plunger back up while you have the port covered, it is not acting as a choke pull off which would open the choke or close it which I'm assuming one of the two does.
Good luck and I'll keep checking this thread as it updates,
Chip.
Quote:
Originally Posted by cyclops34
Looking back at the picture, I see only one canister. Test it like I said and suck on the hose to it to see if it pulls the choke open or closed. I'm thinking the choke closes at the application of throttle prior to starting it and that'll lead to a choking problem. If that is a choke pull off and it won't hold vacuum, it'll stay choked. I'd think most any parts store would have it in stock.
Chip,

I will give this a shot tonight and post back with results.

Cant thank you and the rest enough for your continued help!



BTW, here is a picture of the fuel:

I shook both bottles before taking the pictures.
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Old 12-28-2010, 12:17 PM
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Dang, that's a huge difference. How old is the gas with detritus? Gas goes bad in months now rather than years. Stabil is your friend if your vehicle sits for long periods of time.
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  #21 (permalink)  
Old 12-28-2010, 12:34 PM
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Quote:
Originally Posted by cyclopsblown34
Dang, that's a huge difference. How old is the gas with detritus? Gas goes bad in months now rather than years. Stabil is your friend if your vehicle sits for long periods of time.
I believe the gas was probably last filled in September, so its roughly 3 months old. I hardly ever drive this thing. Its been driven no more than 450 miles since I bought it last December. However, at the very least, I do start and warm it up and drive it up the drive way once a week for street sweep.

Yes, Stabil may be a good idea for this. Actually, I may need to dump it in my other lingering projects as well
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  #22 (permalink)  
Old 12-29-2010, 09:12 AM
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UPDATE: Wednesday, 8:10 AM

Due to the rain today, I won't be working on the truck just yet. I'm hoping it will be okay to do some work when the rain stops this evening. Otherwise, I'll try again tomorrow.


At the suggestion of a member on another forum, I did go and buy a fuel pressure and vacuum gauge tester from Harbor Freight: http://www.harborfreight.com/automot...ter-93547.html


Having never done a vacuum reading before, I did some research and found this article: http://www.aa1car.com/library/vacleak.htm.


Since I didn't see an emissions label under the hood, I am using the following two vacuum diagrams from Chilton's for reference: CA emissions and Non - CA emissions



So now, based on all the advice given and everything I've read, here is a checklist of what I'll be doing:

- Re-gap the spark plugs to 0.045".

- Make sure no wires are arching. Replace and reroute if needed.

- Siphon out as much of the dirty fuel as possible before resorting to dropping the tank and dumping it out. Replace with clean gas.

- Replace fuel filters.

- Test the canister on the carburetor to see if it the choke is working as Cyclops suggested.

- Do a vacuum reading.

- Post all results.
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  #23 (permalink)  
Old 12-29-2010, 09:44 AM
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Quote:
Originally Posted by lt1silverhawk
UPDATE: Wednesday, 8:10 AM

Due to the rain today, I won't be working on the truck just yet. I'm hoping it will be okay to do some work when the rain stops this evening. Otherwise, I'll try again tomorrow.


At the suggestion of a member on another forum, I did go and buy a fuel pressure and vacuum gauge tester from Harbor Freight: http://www.harborfreight.com/automot...ter-93547.html


Having never done a vacuum reading before, I did some research and found this article: http://www.aa1car.com/library/vacleak.htm.


Since I didn't see an emissions label under the hood, I am using the following two vacuum diagrams from Chilton's for reference: CA emissions and Non - CA emissions



So now, based on all the advice given and everything I've read, here is a checklist of what I'll be doing:

- Re-gap the spark plugs to 0.045".

- Make sure no wires are arching. Replace and reroute if needed.

- Siphon out as much of the dirty fuel as possible before resorting to dropping the tank and dumping it out. Replace with clean gas.

- Replace fuel filters.

- Test the canister on the carburetor to see if it the choke is working as Cyclops suggested.

- Do a vacuum reading.

- Post all results.
That canister is a standard choke pull off and secondary lockout. It should open the choke 1/4" or so when the vehicle starts and then the choke should slowly open over the course of 5 minutes or so. It looks like you have the old style choke stove in the manifold. These can be problematic as they rot out or break. The other issue with these is if the wrong intake gaskets are used or the heat riser valve in the exhaust is defective no heat will reach the manifold and the choke wont open. There is a cross over passage that runs through the manifold and the valve in the exhaust closes at low rpm to force some exhaust through this passage to warm the manifold and choke spring. Without this functionality it will still open eventually but it can take a long time.

You need to get rid of that gas to start with and change the fuel filters, that could be half your problem. That filter at the carb is not looking to healthy either.
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  #24 (permalink)  
Old 12-29-2010, 10:00 AM
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Hey Chet,

Quote:
Originally Posted by T-bucket23
That canister is a standard choke pull off and secondary lockout. It should open the choke 1/4" or so when the vehicle starts and then the choke should slowly open over the course of 5 minutes or so. It looks like you have the old style choke stove in the manifold. These can be problematic as they rot out or break. The other issue with these is if the wrong intake gaskets are used or the heat riser valve in the exhaust is defective no heat will reach the manifold and the choke wont open. There is a cross over passage that runs through the manifold and the valve in the exhaust closes at low rpm to force some exhaust through this passage to warm the manifold and choke spring. Without this functionality it will still open eventually but it can take a long time.
The most immediate question for me right now is should I ditch this carburetor all together? (I've got a Holley 650 cfm sitting around but I don't know if it will work with this manifold).


Quote:
Originally Posted by T-bucket23
You need to get rid of that gas to start with and change the fuel filters, that could be half your problem. That filter at the carb is not looking to healthy either.
The filter before the carb was removed and cleaned. But I guess it couldn't hurt to replace it as well. I think the filter element is replaceable.



Thanks for the continued help!
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  #25 (permalink)  
Old 12-29-2010, 11:30 AM
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The first thing you need to do is get rid of that fuel and change the filters. Check the operation of the choke to make sure it is opening.
I would not introduce anything new that is unknown.
If you are absolutely sure the other carburetor is good then maybe.

Is the choke operating correctly, the other very useful tool is a vacuum gauge.
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  #26 (permalink)  
Old 12-29-2010, 11:46 AM
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Quote:
Originally Posted by T-bucket23
The first thing you need to do is get rid of that fuel and change the filters. Check the operation of the choke to make sure it is opening.
I would not introduce anything new that is unknown.
If you are absolutely sure the other carburetor is good then maybe.

Is the choke operating correctly, the other very useful tool is a vacuum gauge.
Got it. The carb swap is, of course, a secondary issue at this point, but something that is nagging me all the same. But I will stay focused! The other carb was rebuilt according to the previous owner, but I am not 100% sure.

Will post results on the filter swap, choke operation, and vacuum reading as soon as I can.

Thanks for keeping me on track Sir!
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Old 12-29-2010, 06:00 PM
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I think the previous owner may have had fuel problems, because those canister filters under the truck are not the stock setup. The OEM setup only had a filter under the hood at at the carburetor inlet. There may have be a reason (bad gas?) the PO added more filters.

If you want to drop the tank, its fairly easy to put a flat board under the tank (2x6 or 2x8) and then support it with a small hydraulic jack. Then unbolt the tank brackets from the frame and lower it down slowly until you can reach the fuel lines to disconnect them. Do not try to remove the bracket & straps from around the fuel tank unless you want to buy all new straps.

Bruce
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  #28 (permalink)  
Old 12-29-2010, 06:19 PM
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Hey Bruce,

Quote:
Originally Posted by 75gmck25
I think the previous owner may have had fuel problems, because those canister filters under the truck are not the stock setup. The OEM setup only had a filter under the hood at at the carburetor inlet. There may have be a reason (bad gas?) the PO added more filters.
Honestly, the previous owner(s) have done quite a few things to this rig, apparently in an attempt to build a cheap hauler that could be used for off-roading as well. Aside from the body and gas tanks, I doubt much is stock.




Quote:
Originally Posted by 75gmck25
If you want to drop the tank, its fairly easy to put a flat board under the tank (2x6 or 2x8) and then support it with a small hydraulic jack. Then unbolt the tank brackets from the frame and lower it down slowly until you can reach the fuel lines to disconnect them. Do not try to remove the bracket & straps from around the fuel tank unless you want to buy all new straps.

Bruce
Thank you for the tips about the straps! The tank itself doesn't seem awfully hard to remove.
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  #29 (permalink)  
Old 12-29-2010, 06:47 PM
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I think you have a weak fuel pump. The reason it starts acting up at highway speeds is probably because it cant get enough fuel to run right. These old trucks with no overdrive turn some high RPMs on the highway and high rpm = high fuel consumption.

You probably had problems with the truck getting up into the driveway because it was cold. With the choke held open with the screwdriver the engine wont be getting a rich fuel mixture which it needs while it is cold, not just while starting. I have to start my carbed vehicles 2 or 3 times when its cold before they will even run long enough for me to rev them up. Then I have to hold them a 2000 or 3000 rpm for a couple minutes before they are warm enough to drive. Thats because I took the choke off of them... lol.

You will have to let the truck warm up a while before you can move it with no choke or a malfunctioning choke.
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  #30 (permalink)  
Old 12-29-2010, 07:12 PM
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Hey Torque454

Quote:
Originally Posted by Torque454
I think you have a weak fuel pump. The reason it starts acting up at highway speeds is probably because it cant get enough fuel to run right. These old trucks with no overdrive turn some high RPMs on the highway and high rpm = high fuel consumption.

You probably had problems with the truck getting up into the driveway because it was cold. With the choke held open with the screwdriver the engine wont be getting a rich fuel mixture which it needs while it is cold, not just while starting. I have to start my carbed vehicles 2 or 3 times when its cold before they will even run long enough for me to rev them up. Then I have to hold them a 2000 or 3000 rpm for a couple minutes before they are warm enough to drive. Thats because I took the choke off of them... lol.

You will have to let the truck warm up a while before you can move it with no choke or a malfunctioning choke.
Damn, no choke? Lol! Why is that?

That the fuel pump might be to blame was my immediate assumption as well. But right now, I can't even get it to stay on to idle and warm up without having to pump the accelerator every few moments. It has a mean lopey idle right now(which sounds good but its not going anywhere ). I find myself siding with the other guys in thinking that the water and debris contaminated fuel is clogging the fuel filters, which is why the truck is starved for fuel. But the fuel pump can also be a part of the problem too.

But it is good to know what you go through when starting your truck in colder weather. I haven't used the truck long enough to say I know it well. But I can say, aside from struggling when starting, it ran pretty damn well, even in the heat of summer.
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