Helping my father in law with his 84 Chevy dully, 6.2. It’s been sitting a year or so with crappy fuel. Won’t start, no fuel at the injectors, we’ve done all the easy stuff, hoping to see if there’s other easy things to do before we decide to pull the injection pump.
-
Welcome to The Truck Stop! We see you haven't REGISTERED yet.
Your truck knowledge is missing!
- Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
- We have tons of knowledge here for your diesel truck!
- Post your own topics and reply to existing threads to help others out!
- NO ADS! The site is fully functional and ad free!
Problems registering? Click here to contact us!
Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!
Hello
- Thread starter Kndrman
- Start date
dbrannon79
I'm getting there!
Welcome to the forum @Kndrman an 84 will be fully mechanical, if you've verified you have fuel pumping from the lift pump (most likely a mechanical one on the side of the engine) though the filter and to the IP, all you need it to make sure the fuel shutoff solenoid on the top of the IP has power with the key on. loosen the line nuts on all the injectors and crank away till you have fuel leaking from the line nuts.
it's gonna take a lot of cranking sessions and will need good hot batteries and a charger too.
remember not to burn out the starter. 30seconds crank, 30 seconds off, 30 seconds crank. do this about 3 times and let the starter rest another 30 minutes. @Will L. has a better approach to this.
if you are unsure about fuel passing through, pull the 6" return hose off the IP and replace it with a clear piece of tubing. after a bit of cranking you should see fuel begin to flow out from the IP in the clear line. Once you see that, fuel will be at the injectors soon after.
DO NOT use the famous mechanic in a can on this engine (starting fluid) unless your prepared to replace the engine!
it's gonna take a lot of cranking sessions and will need good hot batteries and a charger too.
remember not to burn out the starter. 30seconds crank, 30 seconds off, 30 seconds crank. do this about 3 times and let the starter rest another 30 minutes. @Will L. has a better approach to this.
if you are unsure about fuel passing through, pull the 6" return hose off the IP and replace it with a clear piece of tubing. after a bit of cranking you should see fuel begin to flow out from the IP in the clear line. Once you see that, fuel will be at the injectors soon after.
DO NOT use the famous mechanic in a can on this engine (starting fluid) unless your prepared to replace the engine!
Thanks for the follow up.
We started by draining the fuel tank with an electric pump. Refilled with fresh fuel.
Next we verified we have fuel in and out of the fuel filter.
We have fuel coming out the return line on top of the governor cover.
The shut off solenoid was stuck, got it freed up, seems to be working now, can hear it click with an electrical jumper from the battery.
The fuel shut off valve was stuck tight, so we put fuel injector cleaner in the governor bowl, left it set for a couple days, now we have the shut off valve rotating freely.
To save wear on the starter we have pulled the truck down the road about 1/2 mile with 5 of the fuel injector lines loosened at the injectors.
Still no fuel at the injectors.
Is there somewhere else we need to bleed?
Our fear is that whatever had the shutoff valve gunked up is still blocking the fuel through those small passages.
We are trying to see if there’s a way to get injector cleaner worked through the pumping mechanisms?
Really hoping we don’t have to take the pump off the truck.
Thanks for your help
Randy
We started by draining the fuel tank with an electric pump. Refilled with fresh fuel.
Next we verified we have fuel in and out of the fuel filter.
We have fuel coming out the return line on top of the governor cover.
The shut off solenoid was stuck, got it freed up, seems to be working now, can hear it click with an electrical jumper from the battery.
The fuel shut off valve was stuck tight, so we put fuel injector cleaner in the governor bowl, left it set for a couple days, now we have the shut off valve rotating freely.
To save wear on the starter we have pulled the truck down the road about 1/2 mile with 5 of the fuel injector lines loosened at the injectors.
Still no fuel at the injectors.
Is there somewhere else we need to bleed?
Our fear is that whatever had the shutoff valve gunked up is still blocking the fuel through those small passages.
We are trying to see if there’s a way to get injector cleaner worked through the pumping mechanisms?
Really hoping we don’t have to take the pump off the truck.
Thanks for your help
Randy
MrMarty51
Well-Known Member
Hello KNDRMAN
Welcome to the forum.
I think dbrandon pretty well has it covered.
Try removing the fuel shut off solenoid and powering it up through the ignition switch, ensuring that the plunger is extending and retracting.
IDR if it is possible to get the plunger engaged into the IP incorrectly, someone in here will have that infirmation.
Welcome to the forum.
I think dbrandon pretty well has it covered.
Try removing the fuel shut off solenoid and powering it up through the ignition switch, ensuring that the plunger is extending and retracting.
IDR if it is possible to get the plunger engaged into the IP incorrectly, someone in here will have that infirmation.
dbrannon79
I'm getting there!
My guess if the cavity under the top cover was gummed up, it's very possible the head and rotor assembly is also gummed up. this is where it pumps fuel to the injectors. I think the best course of action would be to unfortunately pull the IP and have it gone though, or have a new one installed.
one of the main reasons I say this is with the IP gummed up there are things within that if and when it starts, you could very well have a runaway engine on your hands!
one of the main reasons I say this is with the IP gummed up there are things within that if and when it starts, you could very well have a runaway engine on your hands!
dbrannon79
I'm getting there!
With what Marty is saying on the fuel shutoff solenoid, you can remove the top of the IP where the solenoid lives, DO NOT crank the engine over, but turn the key on with the wire attached to the solenoid. you will need to ground the housing since it's not attached to the IP. and you should see the lever on the solenoid pull in.
Now with installing the solenoid, be very careful that you install it properly. before you put the screws back in, it should want to slide forward. there is a certain spot where that lever has to sit into otherwise if installed incorrectly will leave the IP at WOT (wide open throttle) and will runaway when it starts up. search on youtube for installing the fuel solenoid on a DB2 injection pump. in fact there are some very good detailed rebuild videos on these DB2 pumps showing you how it all works. I would recommend you take some time and watch them, learn all you can. seal kits are available for them and armed with the right knowledge you can tear it down your self to clean all the gunk out.
Warning.... there are some adjustments that you do NOT mess with. 1. the transfer pump pressure screw located inside the cap where the supply fuel line connects. 2. is the fuel metering screw located on the side of the IP under a triangle shape cover which is on the rotor. 3. a pressure screw on the case that has a set nut which also holds the internal throttle linkage.
messing with any of these adjustments can result in very bad things, they can only be set on a test bench. changing them could destroy the IP.
Now with installing the solenoid, be very careful that you install it properly. before you put the screws back in, it should want to slide forward. there is a certain spot where that lever has to sit into otherwise if installed incorrectly will leave the IP at WOT (wide open throttle) and will runaway when it starts up. search on youtube for installing the fuel solenoid on a DB2 injection pump. in fact there are some very good detailed rebuild videos on these DB2 pumps showing you how it all works. I would recommend you take some time and watch them, learn all you can. seal kits are available for them and armed with the right knowledge you can tear it down your self to clean all the gunk out.
Warning.... there are some adjustments that you do NOT mess with. 1. the transfer pump pressure screw located inside the cap where the supply fuel line connects. 2. is the fuel metering screw located on the side of the IP under a triangle shape cover which is on the rotor. 3. a pressure screw on the case that has a set nut which also holds the internal throttle linkage.
messing with any of these adjustments can result in very bad things, they can only be set on a test bench. changing them could destroy the IP.