Would a lower rated radiator cap stop the weeping?
Thread Starter
Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
Likes: 1,174
From: Southlake, TX
Would a lower rated radiator cap stop the weeping?
I have a 91 ZR1 that has developed a small, coolant "weep" around the heater hose, just above the thermostat housing. I just put in a new radiator and have a Haibeck chip that allows the fans to come on at 205 and off at 200.
It is really not that much-- a droplette (singular) forms on the bottom of the thermostat after a run. While running and circulating, there is nothing but when the car is off and the pressure builds, it begins weeping around the "quick fitting."
Since it is small, I'm not planning on tearing everything apart (because Mr Murphy says I'll make it worse) and will just keep and eye on it.
One of the guys on the "Z-net" had an idea of putting on a lower rated pressure radiator fill cap, so the over flow reservoir can "engage" at a lower pressure. The cap is the standard 15lb.
Sounds interesting to me as a 12-13lb may relieve a bit of pressure and might allow the coolant into the reservoir and not out the heater quick fit? Currently my system is operating in such a way as literally no fluid going in or out of the reservoir.
Would that work and how would engine operations be effected?
Just curious....Thanks!
It is really not that much-- a droplette (singular) forms on the bottom of the thermostat after a run. While running and circulating, there is nothing but when the car is off and the pressure builds, it begins weeping around the "quick fitting."
Since it is small, I'm not planning on tearing everything apart (because Mr Murphy says I'll make it worse) and will just keep and eye on it.
One of the guys on the "Z-net" had an idea of putting on a lower rated pressure radiator fill cap, so the over flow reservoir can "engage" at a lower pressure. The cap is the standard 15lb.
Sounds interesting to me as a 12-13lb may relieve a bit of pressure and might allow the coolant into the reservoir and not out the heater quick fit? Currently my system is operating in such a way as literally no fluid going in or out of the reservoir.
Would that work and how would engine operations be effected?
Just curious....Thanks!
Last edited by billschroeder5842; Apr 10, 2017 at 11:57 AM.
Safety Car
Joined: Aug 2002
Posts: 3,842
Likes: 230
From: SANTA CRUZ CA
Going to a lower rated rad cap would lower the boiling point of the coolant. A 15# cap increases the boiling point about 50 degrees.
https://durathermfluids.com/pdf/tech...ling-point.pdf
https://www.physicsforums.com/thread...urized.465289/
https://durathermfluids.com/pdf/tech...ling-point.pdf
https://www.physicsforums.com/thread...urized.465289/
Thread Starter
Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
Likes: 1,174
From: Southlake, TX
Worth the try on the radiator to lower internal pressure (stop the leak) or is this temping fate?
Thread Starter
Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
Likes: 1,174
From: Southlake, TX
Will that bit of lost coolant (really not LOST as it goes to the reservoir) reduce enough internal pressure to take the strain off my heater "quick connect" weeping situation?
Any drivability issues? I'm thinking not but I'll ask anyway....
Safety Car
Joined: Aug 2002
Posts: 3,842
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From: SANTA CRUZ CA
Cap cost is minimal
If the steam pressure exceeds the cap pressure, you will loose coolant,
but nothing with which to be concerned. Will just require more frequent coolant level monitoring.
Safety Car
Joined: Aug 2002
Posts: 3,842
Likes: 230
From: SANTA CRUZ CA
It just dawned on me that we a discussing a ZR1 engine, not an LT1.
Dumb me!
So, yes, bleeding may be necessary.
Does the ZR1 have a reservoir as an extension of the radiator?
Lucky you to have a ZR1....
Dumb me!
So, yes, bleeding may be necessary.
Does the ZR1 have a reservoir as an extension of the radiator?
Lucky you to have a ZR1....
