86 4x4, where to start?
abaird
01-05-2005, 11:18 PM
Where to start. I paid $500 dollars for a 1986 silverado 4x4 with a 305 and what I think is a 700r4. I knew the previous owner well and I think I got a good deal. The truck is a great hunting rig. However, it has so many little problems that are a pain in the a**.
No matter how warm or cold it is, after sitting overnight it is one cold blooded sob. When it finally does start you have to let it warm up for ever or it will die when you put it in gear. When it is warmed up it starts and runs great. What causes it to want to die when putting it in gear, just a tired engine or can something be done?
Also the speedometer doesnt work. It is just the cable but I couldn't get the guage itself out to undue the cable. I was afraid to just rip it out for fear of breaking something. Is there a trick to thisOr do you just pull like crazy?
The heater is another thing. When you turn the fan on you can hear it run but very little air blows out of the vents. Not sure where to look.
Sorry for writing a book. Any help is appreciated, thanks alot. Andy
No matter how warm or cold it is, after sitting overnight it is one cold blooded sob. When it finally does start you have to let it warm up for ever or it will die when you put it in gear. When it is warmed up it starts and runs great. What causes it to want to die when putting it in gear, just a tired engine or can something be done?
Also the speedometer doesnt work. It is just the cable but I couldn't get the guage itself out to undue the cable. I was afraid to just rip it out for fear of breaking something. Is there a trick to thisOr do you just pull like crazy?
The heater is another thing. When you turn the fan on you can hear it run but very little air blows out of the vents. Not sure where to look.
Sorry for writing a book. Any help is appreciated, thanks alot. Andy
J-Ri
01-06-2005, 01:15 AM
Mine had the starting problem (still does on VERY cold days) I replaced most of the external carb parts and that helped a lot. Also make sure all the vacuum lines are hooked up where they should be. On the 350, there's a heat riser on the right side of the engine, make sure it's not restricted.
For the heater, make sure the ait intake isn't clogged with leaves and make sure a mouse didn't get in there and make a nest somewhere.
For the heater, make sure the ait intake isn't clogged with leaves and make sure a mouse didn't get in there and make a nest somewhere.
abaird
01-06-2005, 01:42 AM
heat riser? also what external parts? Thanks
rpreston
01-06-2005, 09:28 AM
The heat riser J-RI is talking about is the little silver flexible pipe that comes off the right exhaust manifold and connects to the air filter housing. It's called a chimney pipe. There's a flap in the air cleaner housing that closes when cold (like a choke on a carb). It's in the horn of the housing. All the air coming thru the air cleaner is heated from the exhaust when the flap is closed. The flap should open when the engine is warm.
Not sure what year model they began using them, but if its TBI, the "external" part he's talking about is probably the Idle Air Control Valve (IAC) on the TBI. The ECM controls the idle, hot or cold, thru this valve. You also might try replacing the Electronic Coolant sensor on the front of the intake manifold (if it has one on a 86???). The ECM uses it to monitor engine temp to control the IAC as well as the lenghth of the injector pulse in the TBI (to run rich or lean).
Not sure what year model they began using them, but if its TBI, the "external" part he's talking about is probably the Idle Air Control Valve (IAC) on the TBI. The ECM controls the idle, hot or cold, thru this valve. You also might try replacing the Electronic Coolant sensor on the front of the intake manifold (if it has one on a 86???). The ECM uses it to monitor engine temp to control the IAC as well as the lenghth of the injector pulse in the TBI (to run rich or lean).
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