This is my first thread in the 2nd gen section but I feel like I learned some worthwhile information that I didn't find find on here about a different technique to burp the system.

Some general info about the truck 1998 qc 1500 sb 4x4 sport 360.

So a couple months ago I did plenum gaskets, water pump, front cover gasket, mopar perfomance double roller timing chain, and a new mopar thermostat. So its been cold here (it just broke 0 degrees for the first time in 48hrs) and my heat sucked after all that work, no air in the system after the work. I got the system to burp by parking it on an incline and running it with the cap off, like most have suggested on here.

Fast forward to friday night. I decided to flush the system with Hotsy break through degreaser ~1:5 (degreaser:water) on advice from a friend at the local caterpillar dealer. Which worked really well except exposing a hole in the radiator and flushing out what seemed to be a $!!# ton of stop leak. The hole was pumping out almost 1/2 gallon per minute. But during the flush I had good heat, even though it was 6 degrees and falling. So after clearing the entire system I brought it in the shop and got radiator from oriellys. Couldn't get the system to burp completely this time. Did it 3 times, each time a little air would come and my heat was luke warm at best on the max a/c recirculate setting. I could hear the gurgling in the core.

Fast forward to today. My dad is a 45yr diesel mechanic and he bet me that he could get it to go with out a vacuum filler system like I was prepared to buy. All he did was take some extra heater hose pieces we use for winterizing stuff and plugged the a piece with a bolt and put that on the heater return tube on the pump. Then put a piece of hose on the hose where it would normally go onto the pump. He then put the extra long return hose he made into the top of the radiator. We started it and nothing would come out. So we shut it off and restarted it. Got a trickle. So after letting it run for 3mins revved it to 2000rpm a couple times and all of a sudden a bunch of bubbles and came shooting out and full flow was restored. Shut it off and hooked everything off as normal. Started it back up and let it idle to operating temperature and took it for a drive. Had to open up my coat after 3mins it was so warm. Keep in mind the truck had been sitting outside for 24hrs at this point and it had finally warmed up to 0 degrees for the first time in almost 48hrs.

I know this is a long post but I feel like this could help those struggling with getting the core to burp the traditional DIY way.

 

Now there is an interesting idea. I am going to have to give that a try, and see if I can't improve my heater performance.

 

I like the idea...

For me, a couple of hard accelerations at low speed usually pushes the last of the air out of the heater core... especially if on an uphill run.

I have a plan to put a couple of fittings and a valve just before the heater core to bypass it in summer... on the top of this I'm putting a radiator drain fitting to use as a bleed point.
I'll report (with pics) when I get around to it.

 

Drill a small hole in the stat, It works wonders! After you fill the system raise the rpm's a bit, This will help flush out the air in the heater core.

 

Really like this idea because it sounds like it has good results. However could somebody explain the process to me, I seem to be missing something here.


So you plug the return on the pump side. Then run the return back to the raditor?

 

Did you put the front end on ramps and run with the radiator cap off and fans kicking in? Works every time for me.

 

Disconnect the hose that comes from the heater core, at the metal tube that does into the water pump. Plug the metal tube. (either a short piece of line, with a bolt in the end, or, I just stuff a cork into it. The system won't be building pressure. besides, that's a return line. )

Extend the hose you just disconnected, so it will reach the radiator fill. Take off the radiator cap.

Start engine, and let it run, hold the return line you extended in the radiator fill. Let it run till it stops giving air. May have to rev the engine a bit to get flow started.

Once you have the air purged out, simply reassemble the system, and you should have good heat.

This would probably also make a good way to flush the system, just route the hose into a bucket, and add coolant as it is being pumped out. (not sure how high a rate it will pump out at....... so, may not be possible to keep up. )

One of these would make life easier. I have one. I LOVE it.

 

I will have to try this. Maybe even tomorrow.

 

This..if it isn't already there. 1/8 drill bit through the inner shoulder rim.

 

Couldn't have said it better. Yes we used a short piece of hose with a bolt to plug that tube. Now mine didn't flow more than 1.5 gallons I want to say, but I didn't time it or anything so take that number with a grain of salt.

We did not have it on ramps, actually the ground was level but our hose was long enough that the bend that formed when we stuck it in the radiator was slightly higher than the core.