Kain
3/4 ton status
i rewired the starter charging system after finding this
CK5
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Engine starts ok, but immediately stops:
- Thread starter vandelay industries
- Start date
It is REAL easy to have the positive battery cable at the starter solenoid,to lean over and touch the small "S" terminal ,which will make it start cranking as soon as you hook the cables to the battery..
I did this myself ,even knowing better--sucks pulling down a 6.2 starter 4 times,they weigh twice what a gas engine starter does..
GM had positive cables with a special 90 degree bend and a "locating lug" made into the crimped end,and that lug must be properly seated in the spot on the solenoid cap ,otherwise it will make contact with the small "crank" terminal and also usually the plastic cap will crack as you tighten the nut to the cable,if it isn't aligned perfectly...if an aftermarket cable was installed ,you must make sure it isn't touching the other small terminal on the solenoid..
You should have at least one thick red wire at the starter,that goes on the same stud as the battery cable does..some years have two wires,others had one..that wire is what sends power to practically everything in the cab..and it has to be hooked up..
I did this myself ,even knowing better--sucks pulling down a 6.2 starter 4 times,they weigh twice what a gas engine starter does..
GM had positive cables with a special 90 degree bend and a "locating lug" made into the crimped end,and that lug must be properly seated in the spot on the solenoid cap ,otherwise it will make contact with the small "crank" terminal and also usually the plastic cap will crack as you tighten the nut to the cable,if it isn't aligned perfectly...if an aftermarket cable was installed ,you must make sure it isn't touching the other small terminal on the solenoid..
You should have at least one thick red wire at the starter,that goes on the same stud as the battery cable does..some years have two wires,others had one..that wire is what sends power to practically everything in the cab..and it has to be hooked up..
vandelay industries
1/2 ton status
UPDATE:
i decided to go thru the starter wiring one more time. This time the only thing i really did differently(if that) was to swivel the wires to insure they are not touching each other (not that they definitely were before) and really tighten things down better.
We are back to----engine shuts off after you release the key from the start position. Although it seems to be lasting longer than the 0.5 seconds previously. Maybe we are up to about 1 second.
i decided to go thru the starter wiring one more time. This time the only thing i really did differently(if that) was to swivel the wires to insure they are not touching each other (not that they definitely were before) and really tighten things down better.
We are back to----engine shuts off after you release the key from the start position. Although it seems to be lasting longer than the 0.5 seconds previously. Maybe we are up to about 1 second.
Can you get a picture of the wiring on the starter and post it up? And a list of where each wire is coming from?
Esc spark control aka knock sensor controller or wiring could have a short somewhere also causing it to shut off assuming the esc is still connected.
Kain
3/4 ton status
sounds like a vats system shutting down the engine.......
had this on the 99 vette ls1 we put into a 94 chevy siverado
had this on the 99 vette ls1 we put into a 94 chevy siverado
vandelay industries
1/2 ton status
i will try for a picture tomorrow---it will be very tight so i don't know if it is possible. In the meantime, i've got battery positive and two red wires on a ring on the large starter terminal and then one smaller (like 12-14 gauge) red wire on the "S" terminal. i'm pretty sure this is the correct wiring.
No vats on an 83 1/2 ton.
Wiring sounds good. I think on some of them the small wire on the "s" terminal is purple, but with all the changes you have done, that is probably not valid.
At this point, it really sounds like ignition, but we can't overlook fuel.
At this point, my lack of GM knowledge kicks in, but I know on most of the older trucks you have a fuel pump relay that is triggered by various things. On some of them, you had to have oil pressure to keep it triggered.
At this point, hopefully someone will jump in and advise for sure, but my suggestion is to locate the relay, make a jumper, and temporarily bypass the relay.
You should hear the pump kick on. Immediately try to start the truck.
If it keeps running, you have narrowed it down and can stop checking the ignition.
If not, you have eliminated the fuel relay triggers.
At this point, it really sounds like ignition, but we can't overlook fuel.
At this point, my lack of GM knowledge kicks in, but I know on most of the older trucks you have a fuel pump relay that is triggered by various things. On some of them, you had to have oil pressure to keep it triggered.
At this point, hopefully someone will jump in and advise for sure, but my suggestion is to locate the relay, make a jumper, and temporarily bypass the relay.
You should hear the pump kick on. Immediately try to start the truck.
If it keeps running, you have narrowed it down and can stop checking the ignition.
If not, you have eliminated the fuel relay triggers.
vandelay industries
1/2 ton status
No electric pump. Mechanical pump.
UPDATE:
i am definitely getting power to the red wire that goes into the batt/b+ terminal in the distributor cap when the key is in the run position as verified thru test light this morning.
Latest proposal is to convert this 4.3 ESC distributor to a conventional 4pin module by taking the pickup coil from a v-8 distributor that i have on the shelf (and this one is known to be good since it ran in the engine that was just replaced in this truck) and changing reluctor wheels and star wheels with the other distributor.
i also replaced the module with a new one last tuesday. Now what are the chances both of them failed---especially if the engine WILL start?
i don't see what else it could be?
STUMPED
Mechanical fuel pump
After it stalls,do you check for spark ?...it is possible for an HEI to make only one or two sparks or just for a few seconds when the pick up coil fails internally..I dont recall you replacing that ?..you can just use a spark plug on one of the plug wires (ground the plug to a metal part)--if it gets no spark after it stalled,then it is possible the module could have fried ,its rare but does happen sometimes..or it could be the pick up coil crapping out..
If its not getting enough fuel that can cause it to stall too,but it would usually sputter and stumble along for more than a few seconds..a quick shot of starting fluid or a squirt of gas into the intake will tell the tale right away if it is starved for fuel..
If its not getting enough fuel that can cause it to stall too,but it would usually sputter and stumble along for more than a few seconds..a quick shot of starting fluid or a squirt of gas into the intake will tell the tale right away if it is starved for fuel..
vandelay industries
1/2 ton status
Yes, mechanical fuel pump.
Now, what i just did was to loosen the distributor hold down clamp completely and then turn the distributor alot by hand with the key in the "on" position and inline spark tester in place.
No spark. i do have power going to the distributor.
Is is possible an HEI would have spark during cranking but not when on the run position? Remember that this is a ESC distributor that i did the bypass to. Although that shouldn't be the problem as i did it correctly.
If the engine starts "healthy" then would this indicate the module being bad---because wouldn't the engine not start at all?
Now, what i just did was to loosen the distributor hold down clamp completely and then turn the distributor alot by hand with the key in the "on" position and inline spark tester in place.
No spark. i do have power going to the distributor.
Is is possible an HEI would have spark during cranking but not when on the run position? Remember that this is a ESC distributor that i did the bypass to. Although that shouldn't be the problem as i did it correctly.
If the engine starts "healthy" then would this indicate the module being bad---because wouldn't the engine not start at all?
If your trying to trigger a spark by simply rotating the distrubutor by the cap with the key on,it wont work--its not like points,where it takes only a 1" of movement to make them open and fire the coil--HEI needs the reluctor to spin by the pick up coil at a pretty decent speed to create the needed "pulse" in the pick up coil to fire the ignition coil..
About the only way to test an HEI properly for spark is to use a ground plug or spark tester in one of the plug wires (or the coil wire,if its not an internal coil),and crank it over with the starter..or use the test light "blink" method I described earlier--that wont tell if the coil is actually putting out spark though,that just tests the module and pick up coil..
About the only way to test an HEI properly for spark is to use a ground plug or spark tester in one of the plug wires (or the coil wire,if its not an internal coil),and crank it over with the starter..or use the test light "blink" method I described earlier--that wont tell if the coil is actually putting out spark though,that just tests the module and pick up coil..
vandelay industries
1/2 ton status
Ok, well when i crank it with the starter the yes, i have spark,---and the engine starts.
Kain
3/4 ton status
is your motor grounded good i have had bad grounds eat those modules
vandelay industries
1/2 ton status
Yes, thru head to cab and battery to alternator bracket.
vandelay industries
1/2 ton status
UPDATE:
Ok, i think i got it solved---apparently(?) there wasn't enough fuel in the bowl. So this time i filled it up all the way thru the vent hole.
It ran for much longer this time---like 3-5 seconds. Also, i propped the choke all the way open. Previously i didn't think this was important either, but when you think about it, it's pretty warm here.
Now, it did stall out again, but i think this was due more so the fact that this is really the first time it has run since Oct 13'
Ok, i think i got it solved---apparently(?) there wasn't enough fuel in the bowl. So this time i filled it up all the way thru the vent hole.
It ran for much longer this time---like 3-5 seconds. Also, i propped the choke all the way open. Previously i didn't think this was important either, but when you think about it, it's pretty warm here.
Now, it did stall out again, but i think this was due more so the fact that this is really the first time it has run since Oct 13'
bp71k5
3/4 ton status
Then it sounds like your fuel pump is dead or filter plugged. Pull the output hose and put it in a can. The manual has a procedure to check how much fuel is pumped after a few seconds of cranking.
vandelay industries
1/2 ton status
i'm willing to do that, but consider this:
fuel pump and filter are brand new....and yes, i know new stuff can be defective.
When i see the engine sputtering out i can still see the inline tester showing spark---even when the engine is stalling out----so i think we can rule out ignition---FINALLY (?).
i can see fuel being squirted thru both jets/"squirters"/(don't know the name of the part) when i move the throttle arm.
So, i'd like to not mess with the pump and filter for now and see if there are any other tips to try to keep the engine running?
P.S. We are now getting at least 3-5 revolutions of the engine before it stalls---as verified thru the inline spark tester vs. before the engine would just cut out immediately after starting.
P.P.S. Fuel is about 9 months old, so i don't think that is the problem. The fuel i'm dumping into the vent hole is recent.
bp71k5
3/4 ton status
Assuming it's a carburetor, are you sure it's tuned properly? I'm not sure what an ESC distributor system is but is this one of those "computer controlled carburetor" systems? I've heard those are evil.
