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HELP! just blew up heater core valve thing... going camping tomorow

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Old Aug 24, 2011 | 09:16 PM
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Default HELP! just blew up heater core valve thing... going camping tomorow

So, I was trying to get at my #5 sparkplug, touched (just freaking touched it!) the heater core line to get a view of the plug and BAM! the plastic valve looking thing that the heater core lines go to blew up and sprayed me with boiling hot coolant. It looks like a proportioning valve (2 lines to/from pump, 2 lines to/from core, and a vac pot)...

Can I just plug the lines coming from the pump until next week when I can get a new part, or do I have to wake up extra early tomorow to bike to the parts store/dealership to get a new one?
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Old Aug 24, 2011 | 09:19 PM
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I just took mine out and plugged the vac line. That was 2 winters ago.
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Old Aug 24, 2011 | 09:20 PM
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Bypass. As in hook the two lines together.
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Old Aug 24, 2011 | 09:21 PM
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here is a picture of it
Attached Thumbnails HELP! just blew up heater core valve thing... going camping tomorow-0824111905.jpg  
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Old Aug 24, 2011 | 09:21 PM
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The factory eliminated the heater control valve '97 up. Vacuum line needs to be capped.
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Old Aug 24, 2011 | 09:23 PM
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Can I just plug the existing hoses straight into the heater core, or will I be miserably hot tomorow?

edit: what size hose (ID) is that? time to get a bypass

Last edited by schadelh; Aug 24, 2011 at 09:26 PM.
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Old Aug 24, 2011 | 09:38 PM
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On a '98, hose from t-stat cover is 3/4", hose to water pump is 5/8".
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Old Aug 24, 2011 | 09:42 PM
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Loop one of the heater hoses from the waterpump back to the thermostat housing.. bypassing the heater core. You wont have heat till you replace the valve.

Be carefull not to kink the hose and stop flow though.
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Old Aug 24, 2011 | 10:36 PM
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Yes, the loop works.
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Old Aug 24, 2011 | 11:17 PM
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Originally Posted by Slick761
Bypass. As in hook the two lines together.
"Loop" lol :-)
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Old Aug 24, 2011 | 11:25 PM
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I bypassed the heater core on my wifes car last year until I had the spare time to remove her dash to get to it..
We ran it all summer like that without issue.. Jeep may be different I don't know, but our Ford did fine all summer..
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Old Aug 24, 2011 | 11:29 PM
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Originally Posted by djb383
On a '98, hose from t-stat cover is 3/4", hose to water pump is 5/8".
You can push a 5/8" hose onto a 3/4" fitting, unless it's one of those super hoses. I would hook the water pump directly to the t-stat cover until he can get a new valve.
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Old Aug 25, 2011 | 01:50 AM
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I got a 5/8" coupler and coupled the hoses together, then ziptied them to the old heater core valve so they wouldn't flop around much since I had to take them out of their bracket to keep them from kinking... the top hose looks like it is flatening out a bit due to the bend, but it isn't kinked. Would that be a problem?
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Old Aug 25, 2011 | 12:13 PM
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Doubt it'll be flat once pressure starts to build.
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Old Aug 25, 2011 | 01:31 PM
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Originally Posted by schadelh
I got a 5/8" coupler and coupled the hoses together, then ziptied them to the old heater core valve so they wouldn't flop around much since I had to take them out of their bracket to keep them from kinking... the top hose looks like it is flatening out a bit due to the bend, but it isn't kinked. Would that be a problem?
Somebody correct me if I'm wrong, but I don't think that would be a problem. Remember ... this is just a "bypass" loop. If coolant doesn't flow through the flattened hose, then more of it will flow through the radiator.
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