Anyone any ideas why my cooling system appears to be over pressurizing ..I have water finding any way out at what appears to be really high pressure?
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The classic reason is a failing head gasket. The pressure should be lifting the seat in the swirl tank cap and venting to the overflow tank though. What temperatures are you seeing? Maybe you have a bad cap, otherwise you may just have leaks.
Perhaps you can borrow a system pressure checker from a friend or fit a pressure gauge to an unused port in the cooling circuit to verify your concerns?
A cylinder compression check might be worthwhile too.
Perhaps you can borrow a system pressure checker from a friend or fit a pressure gauge to an unused port in the cooling circuit to verify your concerns?
A cylinder compression check might be worthwhile too.
Think it must be a badley fitting cap...run 30 miles this morning and had no trouble...strange?....
If the system is too full, it will vent coolant as the engine heats up. Once it finds an equilibrium - that behavior will stop.
How long have you been driving it? Did it work well for a long time, and then do this - or is this your first drive since it came back from the mechanic?
Rocky
How long have you been driving it? Did it work well for a long time, and then do this - or is this your first drive since it came back from the mechanic?
Rocky
I only worked that out the other week after owning mine for a year lol .
You guys need to drive your cars more!
I think a pressure gauge on the swirl tank would be a good ideal. plus a schrader with a bicycle pump filled with coolant for cold testing.
quote:Originally posted by Pishadeperro:
Think it must be a badley fitting cap...run 30 miles this morning and had no trouble...strange?....
A badly fitting cap will NOT cause an over pressure condition. The purpose of the cap is to allow the system to pressurize to change its boiling point. Why did you think it was an over pressure condition?
quote:Originally posted by JFB #05177:
I think a pressure gauge on the swirl tank would be a good ideal. plus a schrader with a bicycle pump filled with coolant for cold testing.
Maybe that might be over-engineering a solution?
Panteras have been driving around for 50 years or so.
If you have the right cap, and water comes out, than the pressure has exceeded the cap rating.
I would worry that if a person was to pump up the system with a liquid-filled bicycle pump, there could be a chance of hitting a pressure that is too high, and splitting one of the tubes in the core...
Sometimes the KISS principle is the best solution!
If it ain't broke, don't fix it. And drive your car enough to know if your car is broken or not!
Every one of the OP's previous issues have been a CND (Can Not Duplicate) by his mechanic, who I have to assume is competent. That is my guess about what would happen if Dean took his car in with this latest complaint.
We have talked a lot about the importance of pressure testing the cap, and making sure you have a euro cap in a euro neck (or vice-Versa) in Dean's previous thread. That might be the first thing to confirm....
Rocky
You are bang on about driving them more Rocky
quote:Originally posted by Rocky:...
Maybe that might be over-engineering a solution?
...If a person was to pump up the system with a liquid-filled bicycle pump, there could ba a chance of hitting a pressure that is too high...
... the importance of pressure testing the cap....
Rocky
I thought your first response was better than the more polite edit
I was thinking of how to verify the "in service" radiator cap was performing versus it on a "testing neck"
any how, it sounds like the same obeservations as last post just differnt wording
(this is the second forum this weekend that told me I didn't know what I was talking about)
We all want to play nice in the sandbox!
Look what happened to Mark (one Rocketship)?
What happened to onerocketship, anyway? I think he got mad at Doug and left!
Look what happened to Mark (one Rocketship)?
What happened to onerocketship, anyway? I think he got mad at Doug and left!
quote:Originally posted by Rocky:
We all want to play nice in the sandbox!
Look what happened to Mark (one Rocketship)?
What happened to onerocketship, anyway? I think he got mad at Doug and left!
Some people take life too seriously lmfao
Be VERY careful in pumping up the cooling system for testing. Most street radiators are only good for around 20 psi before the tubes start to 'balloon', ruining the assembly. This is why no one should be using 25-30 lb NASCAR caps to cure an overheating problem!
A 0-30 psi gauge can be temporarily added in place of the radiator drain fitting and a second one to the air-bleed fitting. When the engine is run, the difference between the two gives an indication of the restriction from the radiator itself. And no holes need be drilled to do the check.
A 0-30 psi gauge can be temporarily added in place of the radiator drain fitting and a second one to the air-bleed fitting. When the engine is run, the difference between the two gives an indication of the restriction from the radiator itself. And no holes need be drilled to do the check.
quote:Originally posted by Bosswrench:... When the engine is run, the difference between the two gives an indication of the restriction from the radiator itself...
Do you have any values?
Something I wondered if the block discharge pressure is limited by the radiator cap, how much pressure (or possible vacuum) is at the pump suction at high temp and rpms
You won't have a vacuum at the pump suction. Otherwise the water would flash to steam.
When I got my car, the expansion tank had a sealed cap, effetively sealing the entire system.
The temps on my gauge bang between 150 and 180, nowhere near boiling.
I'd like to confirm that if I put a hole in my expansion cap, that nothing will change about how my car runs, since it's been running this way for the last 30 years.
I'd like to put things the way they are supposed to be, and what I read, the expansion tank should be allowed to breathe. The radiator cap on the main tank does it's job properly and fills or sucks in what's needed (correct?) but with a sealed system, this isn't happening, because it's all held in suspension because no pressure differences are allowed with the expansion tank cap being sealed.
SO, the car runs and functions fine, should I mess with something that aint broke, or should i put a hole on a cap or get a cap that allows venting on my expansion tank?
The temps on my gauge bang between 150 and 180, nowhere near boiling.
I'd like to confirm that if I put a hole in my expansion cap, that nothing will change about how my car runs, since it's been running this way for the last 30 years.
I'd like to put things the way they are supposed to be, and what I read, the expansion tank should be allowed to breathe. The radiator cap on the main tank does it's job properly and fills or sucks in what's needed (correct?) but with a sealed system, this isn't happening, because it's all held in suspension because no pressure differences are allowed with the expansion tank cap being sealed.
SO, the car runs and functions fine, should I mess with something that aint broke, or should i put a hole on a cap or get a cap that allows venting on my expansion tank?
Sure, go ahead. The cap is mostly there to keep splashing out to a minimum. If the bigger tank is what you're calling the "expansion tank", it's already vented to atmosphere via the overflow hose. It forms a liquid reservoir for the pressure tank (also called a surge tank, degassing tank and a few other names) to draw coolant back into the engine when things cool off. If it was sealed, little or no water would be drawn back.
quote:should i put a hole on a cap or get a cap that allows venting on my expansion tank?
If your car has item #2, it is, and always has been, vented.
Larry