• 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!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

DB2: Air bubbles only when cold advance is on?

Leaking throttle shaft seals causing air is the #1 problem on DB2's. Let us know what check valve you use and where you get it. I need to do it on my CUCV. I'm not ready to do an IP yet so that would be a nice temp fix.
 
Getting really hard to start now that it is cooled off.
We have learned to hit the starter before the glow light goes off.

I will be looking at this harder over the weekend.

Maybe the cold advance air is simply purging the rest of the air out of the housing. This I will look at...

I may have to look at low-rider hydraulic stuff and make sure bio will not eat it up...

S.U.R. and R also makes one
 
I went with the Earl's for 20$ more. Not sure of the quality of the Summit one.
http://www.summitracing.com/parts/EAR-251008ERL/
Be interesting to see if if cures my issue. I would do the IP but I am waiting until srping and hopefully find a db2-4911 to compliment a turbo upgrade and the IP on there now works fine other than the typical drainback so this fix I hope will get me through snow/firewood season.
 
I am watching enough air bubbles to put clear hoses on the carter lift pump tomorrow and see what it is doing. Still worse under cold advance and slower fuel flow.
 
If you are seeing air in the influent line then the leak will most likely be between the LP and the tank. Very common for the sending unit to rot where it bends out of the tank but your in Az not the rust belt so IDK.
 
May have a leak at the pump inlet. Clear tubed the pump outlet and it has bubbles coming out of it. Had my hands full with another project, front end, so this is taking a back seat. Weird as the main tank is full and still getting the fine bubbles.

You can also see the fuel go back as the pressure drops when you turn the engine and pump off. So perhaps the residual pressure with a check valve could keep air leaks sealed.
 
Mabey not so weird that you are seeing air bubbles when the tank is full. There would still be alittle vacume one would think in the tank. So there should be negative pressure from the tank to the LP. So if you had a hole in the line between the tank and the lift pump it would suck some air in the line. I would think.
 
Put clear hose on the pump inlet.... Nothing. :idea:

Looks like the air is from the Carter pump. I used blue lock tight on the inlet fitting on the pump to seal it and new hose clamps. We will see if this helps.
 
Sometimes good info is to be found here. I was scratching my head as to how the pump would make air. The angle I have it at and the motor cooling loop 'storing' air crossed my mind.

New Azone lift pump that has been on the shelf since the Carter install will be going in for testing purposes. Warranty on lift pumps is getting old.

If the air goes away and it is still hard starting:
Then the IP will be changed with the spotless one I just got on the 6.2 engine.

Followed by pulling the injectors for testing.

If it still has air the tank is coming down for a plugged/restricted sock.
 
Update:
Air is gone from loctight use on inlet fitting. Still starts hard.

Now the cold weather has made it easier to start. Just about key it over and it will be smoking blue, missing, but running till it gets some RPM and heat. I am going to recheck the glowplugs. It is like the colder fuel is better to start it. Cold is 28 degrees F and yes that is about as cold as it gets here.
 
Ok I have a simple question.... where do you get clear fuel lines? Is this just a clear piece of any kind of tubing or is it actually fuel rated?
 
You must log in or register to reply here.
Back
Top