1983 Chevy k-20 6.2 diesil

Ok I have a 1983 Chevy Diesil, I replaced the glow plugs, and it seems to start harder, I have been told that its my Pump. But if my pump was going bad wouldnt I have truble while warm also? and is there any way to test my pump ? It seems to be logical, beacuse when I let it sit for like one day no matter if its cold or not I have to pump the petal to get it start. One thing I did notice is that it blows alot of white smoke when first runing then if I rev it
up the smoke goes away. another question that I had is, why even if drive it for 45 min the park it for 2 hours and go try to start it it has to crank, crank .. Do the 6.2 cool down that fast ?? Its about 3 degrees in Minesota, and I barely get it running if it sits got 2 hours. When I plug it in it starts no problem.

Thanks guys

Brandon Motoman69X@aol.com


Junior Member
I dont know much about diesels but they are harder to start in the cold weather, and they tend to take a longer time to warm up.

The white smoke is water that sat in your combustion chamber and is evaporated from the heat.

Also, theres suppose to be filters that remove water from diesel fuel. Check to see if there is a bleed for removing water from your fuel filter, or in the owners manual.

You can also buy diesel additives that helps diesel fuel to stabilize in cold weather, diesel tends to thicken up.

Is there a glowplug idiot light on your dash that tells you when the plugs are warmed up, before you crank the engine? Some diesels suppose to have a seperate fuel heater as an option or a HPCA that advances timing.

I dont have any literature about fuel pressure on the pump.

good luck

Power mad

The white smoke coming from your pipe is from cranking it over and over until it starts. Because what is happening is raw fuel is being injected into the cylinder, not ignighting and then dumped into the exhaust. Then when it fires the fuel build up in the exhaust burns away.If you have replaced the glow plugs and it still doesn't fire, then you need to check the rest of the system. The pump is most likly fine, and pumping the pedal will have no effect on starting, due to the fact that a desiel engine is fuel injected, flooring the pedal only dumps more fuel that isn't burned. pull one of the terminals off of the plug, take a test light, and insert it into the wire lead, turn key to on position, and check to see if wire is hot. You should also hear the controller cycling the plug solinoid. There are several components that regulate the controller. There is a temp sending unit like the one for the temp gage, that tells the controller what the temp is. That is one item that can go bad. Or the controller itself could be faulty. And on a rig that age it isn't uncommon. I believe there is a site for desiel engines that could give you more information but I don't have it, but I have seen it on this forum before. If the controller has gone bad then you can bypass it with a push button switch, which almost all of my customers have had me do rather than spend the money on replacing it.


Junior Member
6.2 Cold Starts

I recently replaced the injector pump. The pump re&re guy described that symptom.

There are a few o-rings which seal the fuel supply on the throttle actuator and the drive shaft for the pump. If the drive shaft seal gets a tear, when you stop the engine, there is a chance fuel will leak out and air in. This air in your pressurized fuel system gives the hard start. If it is warm, there just wasn't time for the fuel to leak out.
It is sporadic because depending on where the pump drive shaft stops determines if it leaks.

The tolerances are very fine, and although you could get a few seals from a kindly pump-shop, I'd pony up and get a new injector pump.. one day it just won't start.

The pump sits beneath the intake manifold and wasn't a hard job if you go slow. Bleed the injectors one by one when you're done.

Also, the dual battery system design is a bit lame, i've installed 2 large capacity deep cycle batteries to give the cranking amps after the glows. this helps really cold starts..

good luck

Top Forums

Similar threads

Similar threads