water pump?

[treeguy]

I'm thinking my m35 water pump is shot, thermostat is good. disconnected heater hoses, run, no gushing coolant. Any comments, (and yes the 2 heater valves are open.)

 

[Westech]

what are you talking about? you mean it was not pumping coolant? Does it over heat? With the hoses off you prob just sucked in a ton of air.

 

[treeguy]

Ok heres the story, my heater had no heat while engine up to temp. Then engine is not over heating. I disconnected the two hoses from the heater core and blasted the core out with a garden hose to clean it. Then I tried to bleed the air out of the heater core and got some, then some fluid but then the flow would diminish to nothing while running the engine. I took appart the two shut off valves to make sure they were open. Still no heat or flow from the bleeder. I then replaced the thermostat with new and tested the old one in 200 degree water and it turned out to be fine. Still no heat. Then I disconnected the 3/4" hose from the water pump and held the other end (while running) and no fluid came blasting out. That is why I think the pump is not pumping

 

[m-35tom]

heater hoses are probably on wrong

 

[Westech]

really sounds like you have a ton of air and low on coolant. Make sure to cram as much in the radiator as you can, I mean FILL IT UP TILL YOU CANT ANY MORE! bleed out the air at the heater valve and try it again. Any "extra" coolant will puke out the vent. But when you think its full most of the time you can get at least 1 or two more gallons in before she wont take any more.

 

[treeguy]

I switched the 2 hoses around on the heater core but I don't think it matters, the fluid should circulate either way thru it. I noticed the hose that goes to the thermostat housing from the heater core is completely empty. This is the highest point in the system. Like you said Westech, I'll try to cram more coolant in there. I just thought that the water pump would force the fluid up and thru the hoses, core, hose and into the radiator forcing out any air slug. Is it worth taking out the water pump to check it out? Shouldn't coolant be pressurized and burp into the radiator from the top? I'm not over heating but could that be because of a strong antifreeze mix and the pump not working? I don't know what ratio I have right now because I've been bleeding, filling, burping so much that this is drivig me nuts!

 

[treeguy]

I may have figured out the problem. One of the petcock valves is threaded into the very top of the t-stat housing, which looks to me like the heater will get no fluid until the t-stat opens. This would make sense why there is no flow from this hose. The TM's show the petcock threaded into the cooling manifold near the temp. sensor where there are 3 openings, 2 of which have plugs in them. I'm going to move the petcock tomorrow to see if this is it.

 

[Keith_J]

Thermostat opening is proportional to temperature. At idle, there isn't too much waste heat so there is very little flow. Heaters should be plumbed to bypass the thermostat but even then, they won't put out much heat unless you are pulling a load.

 

[2Deuces wild]

My heater puts out more than i need. I could send you the excess

 

[rosco]

Sounds like an "air lock" in your heater. System needs to be full with cap on radiator. Bring up to temp, and loosen clamp on heater output hose. Just barley crack hose off of fitting, until coolant comes out & not air. Again, cap needs to be on! And up to temp - you will have pressure in system that will force the coolant in, and air out.

Lee in Alaska

 

[treeguy]

Thanks Lee, if anyone should know about heat, its you guys in Alaska! How the he.. do you drain your air tanks in winter. Do you have any tips for cold starting and use? Do you use a block heater to keep her warm? I'd love winter if it wasn't so cold!

 

[zak]

Check this out for heater hose placement:


http://www.steelsoldiers.com/deuce/26998-heater-install.html