'85 GMC 350 bogging problems!! - The 1947 - Present Chevrolet & GMC Truck Message Board Network

chargedstang89 · 10-03-2002, 01:01 PM

Hi all...this is my first post here, i just registered.

As if you couldn't tell, I'm a mustang guy, but I love chevy trucks!!

Anyways,

Last night, I looked at an '85 gmc 1/2 ton 4x4. it has a 350 in it and about the only real mechanical problem it has is when it gets warm, it boggs out and wants to die when you take off from a stop sign or light. I'm a mustang guy experienced with engine building and fuel injection. I haven't touched carbs for a few years, but I"m thinking possibly the choke is stuck or a vaccuum problem, but I'm not sure. What do you guys think?

I put $$$$ down on it to hold it until I can see if I get approved for the loan or not, but I just want a heads up as to what might be wrong. I"m great with cars, so fixing the problems isn't a big deal for me..just wondering what is going on.

josh

Hooter · 10-04-2002, 02:33 AM

well sounds like a carb problem to me. Check your heat riser. (little rod sticking up on rh side of intake manifold hooked to carb) Check to see if it opens the choke when your engine warms up. Fart around with the timing for a bit. It also could be a bad accelerator pump, in that case its time for a carb rebuild

gchemist · 10-04-2002, 08:53 AM

Check the advance too. It may be slow or not working.

chargedstang89 · 10-04-2002, 10:46 AM

Thanks for the info, guys. Like I said, I'm trying to get a loan to buy this truck still, so I'm trying to get some ideas as to where to start. I'm thinking I'm going to just ditch the stock carb and get an Edelbrock instead. Couldn't hurt.

chargedstang89 · 10-04-2002, 11:45 AM

Also, there are broken vaccuum lines coming off of the motor and the guy has an electric fan on it with a manual switch in the cab. i woudln't mind keeping the electric fan, but i would rather not have to switch it on myself. Does anyone make good relay switches for fans...AND...does anyone know where I can get a picture of an engine compartment so i can see where the lines are going, or a good vaccuum/electrical diagram?

chargedstang89 · 10-05-2002, 12:47 PM

anyone?

gchemist · 10-06-2002, 11:52 AM

chargedstang89,

You can buy a heat activated thermostat from www.jegs.com or www.summitracing.com They sell parts from www.painlesswiring.com I'm going to one the switch from Painless. The fan is activate by heat. They have two settings to chose from 200 on 185 off or ~190 on and 180 off.
For the hose wiring check under the hood. There should be a small diagrm there. If not most parts stores have a Chilton manual available with the diagrams.

This board is mostly 67-72 truck gurus. If want to visit a more active board follow this link I post there too.

10-03-2002, 01:01 PM	#1
chargedstang89 Registered User Join Date: Oct 2002 Posts: 90	'85 GMC 350 bogging problems!! Hi all...this is my first post here, i just registered. As if you couldn't tell, I'm a mustang guy, but I love chevy trucks!! Anyways, Last night, I looked at an '85 gmc 1/2 ton 4x4. it has a 350 in it and about the only real mechanical problem it has is when it gets warm, it boggs out and wants to die when you take off from a stop sign or light. I'm a mustang guy experienced with engine building and fuel injection. I haven't touched carbs for a few years, but I"m thinking possibly the choke is stuck or a vaccuum problem, but I'm not sure. What do you guys think? I put $$$$ down on it to hold it until I can see if I get approved for the loan or not, but I just want a heads up as to what might be wrong. I"m great with cars, so fixing the problems isn't a big deal for me..just wondering what is going on. josh

10-04-2002, 02:33 AM	#2
Hooter My other Love Join Date: Aug 2001 Location: Castlegar B.C. Canada Posts: 4,085	well sounds like a carb problem to me. Check your heat riser. (little rod sticking up on rh side of intake manifold hooked to carb) Check to see if it opens the choke when your engine warms up. Fart around with the timing for a bit. It also could be a bad accelerator pump, in that case its time for a carb rebuild __________________ Castlegar B.C.The great white North (Canada Eh!) Hooter_5@hotmail.com First generation Monte Carlo club pictures of my life

10-04-2002, 08:53 AM	#3
gchemist BAD BOW-Silverado XST Join Date: May 2000 Location: Senior Member from Austin, TX Posts: 6,431	Check the advance too. It may be slow or not working. __________________ Gerardo a.k.a. Mad Chemist Silverado XST videos

10-06-2002, 11:52 AM	#7
gchemist BAD BOW-Silverado XST Join Date: May 2000 Location: Senior Member from Austin, TX Posts: 6,431	chargedstang89, You can buy a heat activated thermostat from www.jegs.com or www.summitracing.com They sell parts from www.painlesswiring.com I'm going to one the switch from Painless. The fan is activate by heat. They have two settings to chose from 200 on 185 off or ~190 on and 180 off. For the hose wiring check under the hood. There should be a small diagrm there. If not most parts stores have a Chilton manual available with the diagrams. This board is mostly 67-72 truck gurus. If want to visit a more active board follow this link I post there too. __________________ Gerardo a.k.a. Mad Chemist Silverado XST videos

10-04-2002, 10:46 AM	#4
chargedstang89 Registered User Join Date: Oct 2002 Posts: 90	Thanks for the info, guys. Like I said, I'm trying to get a loan to buy this truck still, so I'm trying to get some ideas as to where to start. I'm thinking I'm going to just ditch the stock carb and get an Edelbrock instead. Couldn't hurt.

10-04-2002, 11:45 AM	#5
chargedstang89 Registered User Join Date: Oct 2002 Posts: 90	Also, there are broken vaccuum lines coming off of the motor and the guy has an electric fan on it with a manual switch in the cab. i woudln't mind keeping the electric fan, but i would rather not have to switch it on myself. Does anyone make good relay switches for fans...AND...does anyone know where I can get a picture of an engine compartment so i can see where the lines are going, or a good vaccuum/electrical diagram?

10-05-2002, 12:47 PM	#6
chargedstang89 Registered User Join Date: Oct 2002 Posts: 90	anyone?



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.