Coolant surge sound in heater core

Reply Subscribe

Thread Tools

Search this Thread

Oct 28, 2011 | 07:34 PM

sqdqo

Thread Starter

Beginner

Joined: Mar 2008

Posts: 22

Coolant surge sound in heater core

I have a 2000 classic k2500 w/7.4l. When I accelerate and the water pump increases in rpm I can hear the coolant surging through the heater core. Would this indicate low coolant level or something else? Any ideas?

Oct 28, 2011 | 09:17 PM

NullHead

TruckForum Addict

Joined: Apr 2011

Posts: 1,226

From: Detroit, MI

I hear it too, but my heat still works. I guess maybe there's an air pocket in there that gets pushed around?

Oct 28, 2011 | 09:53 PM

Wiked

Senior Member

Joined: Jun 2011

Posts: 368

From: Pennsylvania

yeah i have it

add coolat and burp the system. when you add the coolant hold the rpms at like 1500-2000 and all the air will bubble out. thats how i fixed my problem.

Dec 5, 2011 | 05:20 PM

elkhornsun

Beginner

Joined: Dec 2011

Posts: 27

There are valves to shut off the flow of coolant through the heater block. Suspect that you have one that is sticking and not fully open or closed. Should not be hard for a mechanic to check.