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
How would your expansion tank NOT have a neck vent? was it plugged or neck changed by previous owner?
AAAHHH, yes, it does have that drain line running down, so it IS vented to atmosphere no matter what cap I use (on that particular tank). The other tank has the appropriate pressure cap.
If you use a pressure cap on the expansion tank It will change the pressure relief value on the pressure/swirl tank.
A normal 15 psi radiator cap will "lift" when the pressure under it exceeds 15 psi since the top is vented to normal air. If both tanks have a 15 psi cap, then when the pressure cap relieves the pint or so due to coolants thermal expansion, the pressure in the expansion tank will increase base on the ratio of air/coolant.
say the worst case with the expansion tank nearly full cold, then the expansion tank will reach 15 psi, then that pressure on top of the pressure/swirl tanks cap will add to the spring setting and now it will take 30 psi to lift.
as for the ability to replenish coolant as it cools down, the pressure radiator cap on the expansion will use the vent valve to avoid a vacuum in it as the pressure/swirl tank sucks coolant back in due to thermal contraction
Having the expansion
A normal 15 psi radiator cap will "lift" when the pressure under it exceeds 15 psi since the top is vented to normal air. If both tanks have a 15 psi cap, then when the pressure cap relieves the pint or so due to coolants thermal expansion, the pressure in the expansion tank will increase base on the ratio of air/coolant.
say the worst case with the expansion tank nearly full cold, then the expansion tank will reach 15 psi, then that pressure on top of the pressure/swirl tanks cap will add to the spring setting and now it will take 30 psi to lift.
as for the ability to replenish coolant as it cools down, the pressure radiator cap on the expansion will use the vent valve to avoid a vacuum in it as the pressure/swirl tank sucks coolant back in due to thermal contraction
Having the expansion
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Wel it seems to be functioning fine right now so Ima gonna leave it alone.
I watch my gauge like a hawk. The other day I heard a noise, but think it was the air brakes on a semi truck, but it was a loud HISS, and I thought it came from my car. I watched the gauge extra closely, nothing changed.
On cold days it bangs back and forth between 150 to 180 and back.
On hot days, it does the same until oil temps are up to 200-220, then it bounces between 185 and 165-170 (stays closer to 180). Both of these numbers are totally acceptable to me, so I'm leaving it all alone until I see it acting different, or it goes to unacceptable numbers (like overheating or something).
I watch my gauge like a hawk. The other day I heard a noise, but think it was the air brakes on a semi truck, but it was a loud HISS, and I thought it came from my car. I watched the gauge extra closely, nothing changed.
On cold days it bangs back and forth between 150 to 180 and back.
On hot days, it does the same until oil temps are up to 200-220, then it bounces between 185 and 165-170 (stays closer to 180). Both of these numbers are totally acceptable to me, so I'm leaving it all alone until I see it acting different, or it goes to unacceptable numbers (like overheating or something).
The oil temp is the significant data. 210-220 is perfect BUT you want to get it there asap and hold it there.
You probably have a 160 thermostat in there now according to this data.
Running oil under 185f is absolutely detrimental to the engine. 200 is much safer for a low temp.
Water temps up to about 240 are ok. Those will bring your oil temps up to par.
You really aren't overheating until you are over 250f water.
You probably have a 160 thermostat in there now according to this data.
Running oil under 185f is absolutely detrimental to the engine. 200 is much safer for a low temp.
Water temps up to about 240 are ok. Those will bring your oil temps up to par.
You really aren't overheating until you are over 250f water.
Good move not 'fixing' it until there's really a problem, Mike. Roger once put a check valve in his oil filer line so oil would not drain out when the engine was off and cause engine wear on starting (many filters do this anyway). On a run home from the 'Vegas Fun Rally that year, the plastic guts of his check valve MELTED, slid out of position and plugged about 75% of the oil flow to the engine....
I'm SUPER conscious about oil temps. Coming from racing Porsches, I know just enough about oil to be dangerous.
I warm the car up, idling for 4 or 5 minutes, then it doesn't see over 2000 rpm until I see oil temps above 180. Oil temps when fully warmed up are between 210-230, maybe a little higher depending on how I'm driving it.
I KNOW it is VERY bad to drive your car with cold oil.
It's funny, in my old Subaru forum, people would brag about their oil temps running at 180 after installing their oil cooler (street car) and I caught flack when I chimed in, telling them they were hurting their engines by running their oil too cold.
When I ran Porsches, I saw people remove the oil caps and find white, water conaminated oil, in AIR cooled cars, caused by what they THOUGHT were doing their cars good, by starting and running their cars once a week for a few minutes "to keep the blood flowing", all the while they were causing condensation from the fast heat-up and cool-down from what they were doing.
Oils are rated at 200-220 I think, and have to reach those temps to boil off any water that may have developed inside the engine. Most people don't know this.
I'd rather have my oil temps a little too high than a little too low.
I warm the car up, idling for 4 or 5 minutes, then it doesn't see over 2000 rpm until I see oil temps above 180. Oil temps when fully warmed up are between 210-230, maybe a little higher depending on how I'm driving it.
I KNOW it is VERY bad to drive your car with cold oil.
It's funny, in my old Subaru forum, people would brag about their oil temps running at 180 after installing their oil cooler (street car) and I caught flack when I chimed in, telling them they were hurting their engines by running their oil too cold.
When I ran Porsches, I saw people remove the oil caps and find white, water conaminated oil, in AIR cooled cars, caused by what they THOUGHT were doing their cars good, by starting and running their cars once a week for a few minutes "to keep the blood flowing", all the while they were causing condensation from the fast heat-up and cool-down from what they were doing.
Oils are rated at 200-220 I think, and have to reach those temps to boil off any water that may have developed inside the engine. Most people don't know this.
I'd rather have my oil temps a little too high than a little too low.
GREAT! More fun stuff I learn about my engine. Good thing I'm going through it next year.
Presently though I'm not worried, cold idle pressure is 65lbs hot idle pressure (220 oil temps) is over 40lbs.
Any rpm above idle when hot is 60-70 lbs. I think the bypass spring in the pump keeps it right at or around 60-70 if I'm not mistaken.
Presently though I'm not worried, cold idle pressure is 65lbs hot idle pressure (220 oil temps) is over 40lbs.
Any rpm above idle when hot is 60-70 lbs. I think the bypass spring in the pump keeps it right at or around 60-70 if I'm not mistaken.
quote:Originally posted by Bosswrench:
Good move not 'fixing' it until there's really a problem, Mike. Roger once put a check valve in his oil filer line so oil would not drain out when the engine was off and cause engine wear on starting (many filters do this anyway). On a run home from the 'Vegas Fun Rally that year, the plastic guts of his check valve MELTED, slid out of position and plugged about 75% of the oil flow to the engine....
quote:Originally posted by mike the snake:
I'm SUPER conscious about oil temps. Coming from racing Porsches, I know just enough about oil to be dangerous.
I warm the car up, idling for 4 or 5 minutes, then it doesn't see over 2000 rpm until I see oil temps above 180. Oil temps when fully warmed up are between 210-230, maybe a little higher depending on how I'm driving it.
I KNOW it is VERY bad to drive your car with cold oil.
It's funny, in my old Subaru forum, people would brag about their oil temps running at 180 after installing their oil cooler (street car) and I caught flack when I chimed in, telling them they were hurting their engines by running their oil too cold.
When I ran Porsches, I saw people remove the oil caps and find white, water conaminated oil, in AIR cooled cars, caused by what they THOUGHT were doing their cars good, by starting and running their cars once a week for a few minutes "to keep the blood flowing", all the while they were causing condensation from the fast heat-up and cool-down from what they were doing.
Oils are rated at 200-220 I think, and have to reach those temps to boil off any water that may have developed inside the engine. Most people don't know this.
I'd rather have my oil temps a little too high than a little too low.
Water boils at 212. If you dont boil it out, you will build sludge which makes a specific type of corrosive.
The rating I think is for the point at which it caries the maxim load.
The loading capacity of the oil is so broad though that it almost doesnt matter. You just dont want to cook out the aditives.
Your water temps probably will rise as you approach maximum rpm.
Showing 180 water is showing additional capacity remaining in the cooling system. Lets presume that is 250 or abouts.
On race cars even the sheet metal gets hot.
quote:The other day I heard a noise, but think it was the air brakes on a semi truck, but it was a loud HISS, and I thought it came from my car.
That happened to me last week... I got to work, got out of the car, and heard an angry hissing sound. Unfortunately, it wasn't a semi...
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