ZERO COOLANT PRESSURE
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But they're still due to vapor pressure of the 50/50 eg and the partial pressure of the volume of ordinary air present in the system. (which I so conveniently left out in my previous diatribe above!!!
)
The temp of the solution at the temp sender (near the T-stat) is very likely close to 190F or so..... The temp at the hotter places in the head and block will be MUCH higher and will produce over all much higher vapor pressures.
SO for areas that may get up to 250F or more, the local vapor pressures (Steam pockets) could be as high as 23.3 psia (or more)
The actual pressure on the system in a case like that might be 23.3 -14.7 (standard day) = around 8-9 psig PLUS the partial pressure of the air trapped in the system (due to the Ideal Gas Law ) (the expansion you mentioned!)
I took the above numbers from the Dowtherm 4000 Engr and Operating Guide
And you're implications are right! simply placing a 50/50 mix in a pressure cooker and bringing it up to 190F wouldn't produce anything more than about 10 psia (which is less than ambient......as long as you had NO air or other gasses in the system)
You would have to know what volume of air is present and add the partial pressure of the final temp of that air to the partial pressure of the 50:50 mix of water/EG (vapor) THAT gives you the pressure of the entire system.
My wife won't ask me what time it is anymore........she's tired of me telling her how to build a clock....
And you (better) explained as "Expansion Effect"
Ok I'll stop!
You need to find the leak. You might be able to pressurize the system using compressed air. With the engine off, you should be able to hear air escaping someplace... If it produces NO pressure at all, it's not going to be a small leak
Regards,
Rick
) The temp of the solution at the temp sender (near the T-stat) is very likely close to 190F or so..... The temp at the hotter places in the head and block will be MUCH higher and will produce over all much higher vapor pressures.
SO for areas that may get up to 250F or more, the local vapor pressures (Steam pockets) could be as high as 23.3 psia (or more)
The actual pressure on the system in a case like that might be 23.3 -14.7 (standard day) = around 8-9 psig PLUS the partial pressure of the air trapped in the system (due to the Ideal Gas Law ) (the expansion you mentioned!)
I took the above numbers from the Dowtherm 4000 Engr and Operating Guide
And you're implications are right! simply placing a 50/50 mix in a pressure cooker and bringing it up to 190F wouldn't produce anything more than about 10 psia (which is less than ambient......as long as you had NO air or other gasses in the system)
You would have to know what volume of air is present and add the partial pressure of the final temp of that air to the partial pressure of the 50:50 mix of water/EG (vapor) THAT gives you the pressure of the entire system.
My wife won't ask me what time it is anymore........she's tired of me telling her how to build a clock....
And you (better) explained as "Expansion Effect"
Ok I'll stop!
You need to find the leak. You might be able to pressurize the system using compressed air. With the engine off, you should be able to hear air escaping someplace... If it produces NO pressure at all, it's not going to be a small leak
Regards,
Rick
I have a few radiator caps here. Going to convert one of them to a pressurized testing cap. After the install degas. I'm going install my gauge and test again.
Like you said. This leak should be easy to find with no pressure present in the system.
Thanks all.
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Update
Well, did everything above. New ford degas, thermostat and cap. Started truck and let idle for 10-15 minutes. Coolant system developed 3psi. Kick on high idle and let sit another 10-15. ECT reached 188. EOT, 178. Pressure about 6psi.
Went for a drive. Slowly built pressure up to about 10. Shouldn't build pressure that fast I thought? Nailed it a couple times. Pressure went up to 18. I was very disappointed and drove home,
As expected. When I got out of the truck I smelled coolant. Popped the hood. No coolant puked on degas? Top hose is pressurized. Gauge reading 15psi.
Checked underneath. Coolant leaking down on harmonic balancer. Coolant is covered underneath.
My question is now. Can't really put 2 and 2 together on this one. Sure water is probably shot.
But, would that explain the high coolant pressures or the puking? I know a faulty WP would cause over heating. But, my truck never over heated????
Anyway gotta find a WP. Ford is closed and I'm not sure about purchasing one from AZ or O'reilly's???
The last pic is as the truck sits now. 12psi on the gauge. No puking and to the max fill line.
Any feedback appreciated.
Went for a drive. Slowly built pressure up to about 10. Shouldn't build pressure that fast I thought? Nailed it a couple times. Pressure went up to 18. I was very disappointed and drove home,
As expected. When I got out of the truck I smelled coolant. Popped the hood. No coolant puked on degas? Top hose is pressurized. Gauge reading 15psi.
Checked underneath. Coolant leaking down on harmonic balancer. Coolant is covered underneath.
My question is now. Can't really put 2 and 2 together on this one. Sure water is probably shot.
But, would that explain the high coolant pressures or the puking? I know a faulty WP would cause over heating. But, my truck never over heated????
Anyway gotta find a WP. Ford is closed and I'm not sure about purchasing one from AZ or O'reilly's???
The last pic is as the truck sits now. 12psi on the gauge. No puking and to the max fill line.
Any feedback appreciated.
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Looks like XDP has the best deal plus 10% off.
Logistics Pro
Joined: Feb 2005
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From: Upper Left Coast
Nailed it a couple times. Pressure went up to 18. I was very disappointed and drove home,
As expected. When I got out of the truck I smelled coolant. Popped the hood. No coolant puked on degas? Top hose is pressurized. Gauge reading 15psi.
Checked underneath. Coolant leaking down on harmonic balancer. Coolant is covered underneath.
As expected. When I got out of the truck I smelled coolant. Popped the hood. No coolant puked on degas? Top hose is pressurized. Gauge reading 15psi.
Checked underneath. Coolant leaking down on harmonic balancer. Coolant is covered underneath.
I would probably get the AIRTEX replacement model. (AIRTEX is the OEM for many different companies and I think you can get a lifetime warranty from some suppliers
And I think they all have metal impellers nowadays......)
I am more worried about your coolant pressure "spiking" under hard acceleration. If that actually happened, you may have other problems. (like a leaking headgasket(s)
Laughing Gas
Joined: Jan 2007
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Did you release all pressure after getting hot then test drive to ck degas tanks pressure?
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Elder User
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I don't think a bad WP can cause such pressure. Bit i guess its possible if there is not enough circulation while driving? I did notice flow to the degas tank at idle. Maybe the impeller is spinning just enough at idle and not while driving?
218K, original WP.
I'm guessing I will still have and pressure issue once the pump is fixed?
Laughing Gas
Joined: Jan 2007
Posts: 883
Likes: 5
Get that pump replaced with the right size pump, then get it hot,release all pressure and go test it, do a few hard pulls then see how much pressure.
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Right now all you know is you have a weeping pump, not that the impeller is loose or anything that would not allow normal flow. Zero pressure would allow hot spots in the head to boil whereas pressurized containment, even a few psi, would not.
Laughing Gas
Joined: Jan 2007
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x2, good advise to anyone leaking coolant in the spot he has in photos,i had one leak and almost fool me, [dont take much].
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I think I'm done.
I think I'm done with the ford's. I've had this truck for almost 6 years. I knew buying this truck was going to be a maintenance issue. But hey. I've been turning wrenches forty years. I can do it. Well, I'm tired of doing it. We as consumers should not have to spend so much time worrying about the truck we're driving! We spend a lot of time looking ato temp spreads, fuel pressures,
. Am I frustrated. Yeah, I'm sure am. Tired too. I think breaking the oil filter stand pipe had me sit back and reflect. In my 40 years of driving. I have spent more time fixing and worrying about this truck than any other diesel I've owned. This is my first, and last 6.0. Had two 7.3's prior to this one. Both 7.3's drove well and only had to put a WP on my last one I sold in 2007.
Anyway, this is my rant for this evening. This truck is paid for. So, buying something else just to get in huge debt is not in the plan.
I'll finish the repair the best I can and send it down to SDS for future repairs. He's only 2.5 hours from me.
Signing off for the night.
Eddy
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Dont blame you eddy,2.5 hrs away from sds might save your sanity and knuckles,and he can take care things you might not see or look for,ive turned wrenches over 40 myself but it gets to you after awhile and you just wanta drive and enjoy it ,and life.