FredR

Mark,

You know your car better than anyone else, you know how it behaves during race sessions so you clearly understand when something is not as it should be. When behaviour changes it invariably means something has changed and invariably it is not something for the better. You could have an issue wherein the system is not sealing under some circumstances and holding under others, not really likely but nevertheless I dare say it is possible [heat expansion closing something off for instance]. Did you get a high temperature alarm annunciation [the big red letters/graphic]? As Glen quite rightly says pressure causes the hoses to firm up, not whether it is water or steam in there.

In the cooling circuit pressure is your friend. The system is pressurised by the coolant heating up to boiling point and it will stay liquid as long as the pressure holds, let the pressure off and it will boil immediately irrespective of whether any further heat is added.

A cold pressure test does not tell you everything but can tell you a lot about the leak path. If you carry out such a test and leave it for an hour or so the pressure should pretty much stay the same unless of course you have a leak. This may not tell you what is wrong but it will sure tell you what parts of the system are sound. If the hoses, the y piece, water bridge & the expansion tank are holding and pressure is being lost the problem is either somewhere in the water jacket or the water pump.

You can do a very quick test without disturbing anything other than the radiator overflow line that can be used as a pressurising connection to the cooling system using some rubber pipe, a tee and a mity vac pump [at a pinch]. If the external kit is not leaking then the problem is with the internal kit. At this point you need to remove the accessories and the belt cover and then you should be able to tell if the leak problem is on the water pump. At this point you can slacken the belt tension to see if you can detect roughness in the pump bearing or you can remove the pump for further inspection if [as it seems you currently believe] the problem lies within the pump.

How long does it take you with all your experience to get the water pump off- a couple of hours?

Running the car further when you do not know what is wrong does not seem to make much sense to me especially if it is the pump bearing that is going south [hopefully not the case].

Rgds

GregBBRD

<br /><br />Quite a bit of conversation about soft hoses, which doesn't require much thought. Pressure makes the hoses seem hard....regardless if the pressure is from water or air.<br /><br />Soft hoses indicate low/no pressure, which was confirmed by you being able to remove the cap.<br /><br />Depending in the concentration of supplements added to the water, water boils at 212 degrees, without pressure. I don't have enough information to know how far your additives extend that boiling point....but if the "mixture" was boiling after you came off the track, I'd guess you would have seem the effects of that....<br /><br />The only way to have no pressure is from some sort of leak or the engine cooling down significantly.<br /><br />You've not indicated a time period thst the car sat, before you removed the cap....so it is tough to judge anything from that.<br /><br />The most significant thing you've said, in three pages, is that there is now a water pump noise.<br /><br />Keep in mind that there is a tiny seal keeping hot steaming water from a greased bearing. If that seal leaks beyond normal seepage the grease will be washed away in mere seconds....and the bearing will fail seconds after that.<br /><br />Start there.

mark kibort

Thanks Greg.. I just thought of something else.. acutaly, when i came in the pits.... very hot still, but not boiling i was able to remove the cap, ,no issue. it was still at the white line, so this proves that it was able to run at high temp, not overall boiliing..maybe local boiliing, and not pressurize the system due to the missing water. kind of my theory from the beginning

I started it back up and made my way back to my paddock space.. took the long way and went faster than normal to get some air flow too as well as the fans blowing.. got to the pits.. temp still at white line and lines still soft. ( cap on)

i think it proves the point that the air lock in the system could prevent circulation and possibly the temp readings were higher than normal if there is no water , you get engine air heat as a source... so who knows how hot the water really was.

my question is also about the bearing. say it leaked the water out and then washed out the grease, that could kill the bearing..... is the bearing a sealed bearing or is it lubricated by the water as it seems some are talking about.

Im trying to rule out everything , find the cause before i start ripping it all apart and replacing the waterpump... which probably need to go anyway because of the noise its making.

thanks... .and all advice is appreciated.... im not dismissing it. im just thinking and discussing it.

mark kibort

Thank for the level setting advice... yes, i agree.. but I have a theory since the car was run yesterday to full temp... no issese (keep in mind i burped the system, added water to full and then started the tests) .

remember i came into the pits with the reservior near full? lines were soft?

this means NO pressure.. cap came of no issue.... temp way high , at top white line and during the race when i backed off and gave up, it was over white line slightly. (overheat) no warning light , but close. pump had to be working.. because fans were activated. (sensor on bottom of ratiaotor) . ive had bad pump before... the fans dont go on, but car overheats, because ratiaotor is cold. and T-stat not opening willl do this too (i had this issue a long time ago)

so, my theory is that, when you race, you get some boiling on a hot day and i lose a little bit of water over a couple of sessions. but i always add when cool. this time i didnt. im thinking it boiled , there was no safety margin, because there was already air in the systems , and it pushed out some water, made some aditional voids in the water pump area and that restricted flow.

PROOF: guys, im in the pits .... cap is on... no leaks, lines are soft. how is that possible? its possible because when the lines pressurized initially and pushed the water out, i backed down, turned on both fans, and the steam condensed , volume went down, hoses became soft. air is already hot, its not getting any hotter , nor is the water. its a stable system.
again, proven by the fact that in the pits and paddock the cap could be removed. and with it back in place, the lines never regained pressure. the only way that i can think of as a cause, would be the overflow container cracked... but my tests so far, show NO leaks and no pressure reduction with the system. 30mins later, the lines were stilll hard...... 1 hour later, i could remove the cap with pressure being released.

If there is a lot of air in the system, the lines willl be soft (a boil over will do this) you cant get the water back in engine until it cools off a bit)
so, i had the engine in the paddock.. after the race... cap still on , lines are soft... they never pumped up.... how is that possible without a leak???? iif i had a leak, wouldnt there be a drop of water as i have seen with last years water pump failure..(last race of the season.. putting the car on the trailer, and there is water coming out of the water pump.. very slight... no problem with the race, just a slow leak and very visible and no issues with pressure)

James Bailey

Just went out to my driveway and saw that a tire is flat on the 1963 Belair. Any ideas why ???? It had air in it yesterday , had air two weeks ago. Now when I feel the tire it is soft but was hard before. Thinking I might drive it around to see it the tire fills up again. Good news is only the bottom of the tire is flat the rest looks good ! Figure it has an "air lock in the system".......

mark kibort

could have been full yesterday at 110 temps and last night it was freezzing??

I know you are making a joke out of this, but ive been down this route probably more than many. remember my rig to peg the t-stat and then mount clear hoses to upper and lower radiator hoses and use a garden hose to see if the pump was working.

think about it.... in the pits , temp at white line, hoses were soft......cap on..
if there was a leak, there would be water loss and visible waterleaking. NONE
why didnt the hoses pump up... they were soft when i got in the pits and stayed soft...... if air is in the system (not just the top of the reservior), the lines will be soft, ONLY if you release the pressure that normally willl build up by warming the engine up. then you have an air pocket and i dont think it will expand anymore... its already at temp.. nothing going to change the pressure now, unless the temp goes up and its already near boiling (not at boiling)

this is the part that makes sense to me,but maybe im not viewing it correctly.
bottomline... its in the pits.. upper white line and lines are soft. leak or void filled with air?

BC

FIFY

mark kibort

Now Bob, boiling doesnt create air? isnt that the definition of "BOILING"?

so, i did the test again. but didnt drive it, in case there is something rubbing on the block. got the engine up to temp. LOTS of pressure.. normal as it got to normal temp. fans clicking on.. and radiator hot , top to bottom. bearing noise very slight now.. but with a stethascope, you can hear the bearing noise quite loud, coming from the pump. radiator cap holding pressure, no problem. no leaks. 30 min later, still hard as a rock. hour later soft.

brought it back to temp by running for 5min and then turned on the fans after they turned off autmatically and opened the cap with gloves and a towel to cover. it boiled over and puked a couple of quarts....... like what probably happened in the race. put the cap back on and hoses were soft..... stayed soft, even thoug temp started to rise. i eneded the experiement there. not conclusive, but kind of simialar to what might have happened at the track



tell you what... ill do the compression test just for you and see if you are, well, 1/2 right. the plugs will show some signes of YOUR theory that the head gasket blew. but if it did, i wonder why around town a couple of days ago, there is no sign of a head gasket issue... no smoke, steam, fliud level stable, no oil in water or water in oil........ so, i think the only thing that happened was an overheat due to voids in the cooling system , and could have been caused by the water pump... IF the water pump has failed, the impeller would have to come of the shaft and be slipping, other wise, its got to be spinning , or grinding into the block... and if that is the case, im sure it was still pumping water. (i hope that didnt happen, but we wil find out). or if it was grinding then there would be wear on the back of the timing belt,and it looks fine.. no signs of wear.

dr bob

Ahem...


No. Boiling creates steam, a heated and in this case saturated vapor of water. No air is "created". The pressure of the steam in the system is a function of temperature, and the actual liquid that's boiling. Pure water boils at 212ºF at sea level. As pressure goes up, the boiling temperature also increases. When the system won't hold pressure, the boiling temperature stays low. When the temperature drops, the steam "collapses" as it condenses back to liquid. Somehow, your system failed to hold pressure, and managed to leak some of the coolant out either as vapor or as liquid.



Your "testing" is nowhere near what you experienced on track day. Not nearly as much heat input.


So where did the coolant go on track day? That's the burning question. Doing stand-still or even drive-around "testing" with less heat load will not get the system pressure up high enough to find the leak, obviously. You've managed to prove that to yourself a few times now, but don't recognize the insanity in your test protocol. Do the same thing over and over and expect a different result certainly qualifies.

HOW MUCH PRESSURE DID YOU BUILD IN THE SYSTEM DURING YOUR TEST? The answer is that you don't know. It just firmed up the hoses and made them warm. When you stopped adding heat, the hoses went soft again. Want to put pressure in the system before your next 100º+ race day? There's a tool for that. Go borrow that tool at your local parts store, and use it to pressurize the system to 15 PSI and see where the water comes out. Fix that.


Got noises from the water pump area? Could be the water pump bearings. Or one of the other big belt rollers that are attached to the pump. Those are the same rollers and bearings that you decided not to replace when you did the belt and pump last time, because they "looked OK". Until you disassemble, you have no clue what's making the noise. It could be the pump. If your leak turns out to be through the water pump seal, it's likely the pump bearings have been washed by hot coolant. But you won't know until you pressurize the system and find the leak.


Mark, I can cure ignorance with knowledge and education. Trying to cure stubborn and stupid is a waste of time. Let's not waste any more time.

Swing by the parts store for the tester on your way home from Taco Bell this afternoon, and use it to test the system and the cap. Find the leak. Fix the leak. Fix every leak. Replace the cap with new. Throw two aspirin in the reservoir and call me in the morning if the condition persists.

mark kibort

Bob, those are good points and im listening. just evaluating all my suspicions.

yes, the test i did in the driveway doesnt allow for what i had happen to happen...
what i was referring too (and you are right about steam vs air.... to a point.... technically, air can be steam, but i get your point)

my test allows for boil over, ejection of fluid, but not the contraction as pressure starts to build again. i changed a variable... opened the cap.... poor test, i agree.

I dont think its the rollers, as the noise is very very specifically located. im on the mounting boss that is the closest flat surface to the pump and you can hear the noise... plus, ive heard water pump noise before as well as roller noise.. they are not alike. but, im not betting my life on it.... always a question.

what im thinking , and hear me out.... the air in the system from the beginning caused the over heat as that void became larger with air (steam) as it localized boil. (if the pump failed, it caused the boil over too... but this kind of failure might have to be the intermittant type... impeller slip) but still under pressure.... then the system is closed so it never opened up, (one way valve for the pressure to force out the air/steam) . the boiliing water pushed out the water through the cap... that often happens in a boil over. in my case, it had about 15min or so to eject 2 quarts...... then as the engine cooled the steam condenses because the volume of air/steam condensed, the lines contracted and was the cause of the soft hoses, even though the temp was at the upper white line.. which might be even higher than actual, if there is more air than water near the sensor. think about it.. its a closed system under pressure, the water is ejected through the overflow, 2 quarts, thats a lot of volume, and when the boiling stops and there is all that pressure that came from the boiling. if i was able to get the temp way down, to below 212, the boilign would stop and the condensation would bring the volume back down. (soft lines) ..... remember i sat there and ran the engine with the temp going up and up again. .... ..........and the lines were still soft. cap on.... so if the temp was so hot, why no boiling... and if there was boiliing, why were the lines soft? there was nothing leaking . not a drop of water



Bottom line, its not leaking as i just tested yesterday, BUT, if you think it is... ill get the pressure tester just to confirm....
Again, just discussing...dont roast me on this ..... many times ive been ok with my assessments of situations... remeber the front wheel bearing howl and using the existing inner races????? they are still working fantastic after you blasted me on that one too last summer!

EDIT::GOING TO THE AUTO PARTS STORE FOR THE TESTER NOW!!!

FredR

[QUOTE=mark kibort;13640697]

.... technically, air can be steam, but i get your point)


Mark,

Air is a gas, steam is a gas, air is not steam & steam is not air.

Air can exist in equilibrium with relatively small amounts of water vapour [humidity]. Air heated to over 100C mixes freely with steam.

Whilst the system is heating up it will contain air, water vapour and mostly liquid coolant. The system is allegedly self venting and the air/water vapour should only be in the header tank.

As the system heats up the coolant starts to boil at a temperature several degrees above the boiling point of water becuase of the glycol content. If the system holds pressure, the water cannot boil and the system pressure increases to the saturation temperature of the coolant. If the pressure rises to 15 psig the relief device in the expansion tank cap lifts to relieve the pressure. Take the cap off the expansion tank when the system is heated and at pressure and steam will be accelerated to sonic velocity through the resulting aperture and the velocity is such that it takes boiling liquid with it at sonic velocity hence the danger associated with removing the pressure cap on a supressed system.

Trust the above helps a little.

Rgds

Fred

mark kibort

Ok...................Bob and the others helping.............
I rented the pressure tester for the cap and the engine and both are holding 16-18psi . the engine was pressureized to near 18psi and i came back an hour later and no leaks and no movement of the needle.
the cap lost a little pressure in 15mins. 13psi (as the cap starts to release pressure at 13psi)

I also visited Greg's 6 liter and listened to his water pump with the same two types of stethoscope. you can definitely hear his lifter noise at that point, but there is no water pump inconsistent bearing noise as i have with mine.

At this point, does it sound reasonable that either the pump has a impeller problem (intermittant slipping on the shaft which is very unusual for metal impellers) or its how i described the problem to start. there was an air pocket caused by overheating, that started with an air pocket in the upper hose, tstat area. it grew as the engine heat started to localize boiling and that pushed out the water out of the overflow...... with all sytem pressure containment in place, as the engine cooled (I stopped redlining and WOT) the system contracted, there was no boiling . temp readings were erroneous due to air in the sensor readings (reading higher than was actually happening in the water). radiator fans were running.

AT this point, its my only theory, but it is plausible , no? i have no other answers. this car can run cool as a cucumber on race days at 100F at thunderhill.... so cool that the fans turn on and off during the race if it is an 80-90 degree day. I only use the 2nd fan on the super hot days when it climbs above mid level. (and that brings the temp down usually with in a lap or two)

mark kibort

Yes, we are getting a little bit technical here.. air is not steam and steam is not air.. but there can be steam in air. i think that is my point and you understant what i am saying . the steam or water vapor is created under pressure, and it condences back into water if the temp is lowered or the pressure rises.

you remove the cap under normal temps, and you can see the system boil and the boiing move through the system quicky, almost instantly, as it fires out the opening. all of us have seen this.

however, think about it.... in the race i never removed the cap as it heated and cooled down on the track. even though the temps were high in the paddock, that reading was from the top of the engine, where there might have been a water vapor area void. eitiher way.. hoses were soft, temp read high, fans were running due to 180F temps (sensor switch limit at radiator bottom) .

If there was a leak, i would have seen it , and it would have been detected .

the only other way there could be low pressure lines, is if the water was leaking into the engine , but then we would have seen steam in the tail pipe, and plugs would be very clean (or one near the leak)... im pulling plugs next.

Im not arguing here, just introducing ideas that could be the cause of the issue. just trying to solve the mystery, because it seems like one.

so far im left with two ideas...
1. air pockes before race caused the overheat. (ive seen this before)
2. water pump failed , slipped on shaft and caused the overheat
3. either way, cooling during the end laps of the race (100mph, low throttle)
allowed for contraction of the system and gave the soft hoses after boiling pushed out the 2 quarts.

[QUOTE=FredR;13642010]

S4ordie

Some blockage in the radiator could cause these symptoms as well Mark. I'm accepting of the air bubble scenario you describe but what caused the original over heating n the first place that caused this condition?

mark kibort

the radiator is so clean..... the water is always just been distilled .
i have suspected that for many of the pump and t-stat failures as the radiator remains cold at the bottom, but proved it to be pump or t-stat failure (and the failure of the t-stat sometimes is caused by air in the system, as it doesnt heat up and open, but the engine can still over heat.

im thinking the root cause here is the air in the system to start, or the pump intermittent failure. starting to think that was the cause and not the pump making noises due to the starvation and caused a slight bearing damage. i dont hear the whirlling noises anymore ,but with the stethoscope, it certainly doesnt sound normal in there. and keep in mind, i just ran the car around town on monday, up to temp and things are behaving perfectly normal, on a very hot day. ( after burped the system and levels were checked!) i just cant believe i forgot to check the water levels before the race.. I always do that!!!! uggggg..