dezl-andy

ive got an 01 truck that makes a gurgling noise in the heater core, like its getting air in the system when shut off? anyone hear of this and whats the fix. the truck has done this since i bought it and when i changed the antifreeze a few weeks ago i never had so much trouble getting the system full.

dezl-andy

it also doesnt loose or use any anti freeze.

totalloser

I dunno if there's a practical way to fix it, but mine did it since I got it, and after replacing the heater core, it still did. Thing seems to like to trap air. I don't see how it could hurt anything tho.

As to coolant, last time I changed mine it was really stubborn about burping the air out of the engine. I think next time I'll pull the thermostat when I refill the coolant. I'm gonna guess unrelated issue.

dezl-andy

hmm, ive never had a truck do this and it just worries me. the other day i pulled 22k behind it, ran in 5th gear 1900rpm it pulled fine at about 950 -1100 but when i cam to a stop it made that same noise for a few seconds?

totalloser

Usually does it more when cold on mine. I figure this is because the stat is closed so more flow is available to go through the heater core and make that funny noise.

I just put in a new core so I had it all in my hands and it's pretty obvious why it traps air. The two hard pipes on the thing are right off the top, and the coolant has to flow downhill to get back to the lines along the exhaust manifold. Probably not enough flow from the water pump to blast the air downhill.

dezl-andy

i can see why i might do that when starting but not sure why it would do it wile running under a heavy load.

dezl-andy

anyone else heard of this? how can the system be getting air in it.

totalloser

Any time the stat closes it will tend to do it more. Think about it- iron holds a lot of heat, and the factory stat fluctuates the temp a bit. That means as you come off a heavy load the stat stays open for a while, but as the temps come down it might close off a bit. With engine rpm high makes the air trapped in the pipe gurgle.

Not a big mystery, also not a big deal IMO. Pop your hood and look where the heater hoses go. UPHILL to the pipes that go into the heater core. It's *designed* to trap air.

Dieseldude4x4

My 1999 has been doing it since about, well, 1999 when I bought it new.

dezl-andy

well ive owned more than 8 of these trucks and never had one do this till now. the truck has a fire ringed head on it and im starting to think something is going on.

totalloser

Well I guess you are already the expert then. So why did you ask?

KATOOM

Here ya go.

http://dodgeram.org/tech/dsl/trouble.../isb_noise.htm

http://dodgeram.info/tsb/1999/09-04-99.htm

totalloser

Hm, neither one of those scenarios sounds like mine, so disregard my posts if those sound familiar. Mine sounds like pouring water from one cup into another, and only before the thermostat opens.

Sorry for the snide comment Dezl-andy, but I really don't think your noise has anything to do with the head except that the coolant was probably drained when the head was put on.

If it really bugs the heck out of you, you could put in a in line petcock on the return line from the heater core above the exhaust manifold and crack it with the engine cold and idling to let the air out.

dezl-andy

ok, i took the fitting out of the head and there is NO rubber tapered piece in it... BUT the metal fitting tapers down to approximately 1/4 inch. how much does the rubber piece take it down?

dezl-andy

im also still concerned about it being under such pressure. ive never noticed any of my trucks havng the upper radiator hose under so much pressure. is there any way to check that? i dont want to let it go till it blows one of the hoses off and leaves me sitting on the side of the road.
its possible i may never noticed on my other trucks also. i just want to know i can hop in the truck and drive without having to worry about stuff. i wish it was bone stock and never messed with. im getting ready to throw a set of rv injectors and hx35 back on it!