So driving home from the autox It was very odd...

Driving TO the autox it was 185 the whole way goin 65 (shut up... 2900 for 20 min is not something I liked)

Driving home it was a different story... First bout 5 mins it was about 190. next 2 mins it climed to 195, next 2 mins it climed to 200.
I wasnt really worried. I have in my head that over 220 is bad.
So I played around with speed, my fan and such to see if I could make it go down. but it kept going up. all the way to about 215 when I said that its time for a little rest and pulled off the freeway about 5 miles from home (didnt know at the time) and called dad and some other people to pass the time, ate some beef jerky, bla bla bla...
So right after I pulled off I got out and checked my manual thermostats on the radiator (cooking temp guages stuck all the way in the little holes in the radiator... One on the hottest (top left) and one on the coldest (bottom right) portion of the radiator..
Reading read, 215 hot, 165ish cold....

So after letting it cool for about 10 mins, checking the overflow tank (had about 2 in of coolant in it) and other stuff, I set out again.

Temp jumped right up to 190, then 200 and stayed right there for a little, then bumped to about 205 and 210 some time later. Stop lights are not much of a problem, It stayed at whatever it was at and it generally goes down a tid bit.

Arived home at 215.

Whatcha guys think? Im driving around town now at 200 and 210 ocasionally.

I want it to stay at 190...

IM thinking that I will get my oil cooler installed, Fiberglass the bumper to force air into the front trunk (it can go elsewere currently.. the opening is not sealed by the bumper) and get different fans and shrowd the air. Possibly take off all my copper stuff and check for crimps of any kind.

Andrew

Sounds like an airflow issue to me. As I recall, you are venting through the hood and not through the inner fenders. Is the exit hole 2x the air inlet? As RH says, the air expands when it is heated and needs more room to escape.

I found a great difference on my first V8 car when I went from a "special edition" spoiler with a small cutout to a "ultimate" air dam with a large scoop. If made a big difference on the interstate. I also found that there was some room for the air to pass around the radiator on my first conversion (RX7/914). I installed some closed cell foam (not the sh*t in the can from Home Depot!) around the sides of the radiator and this also helped. Forced air follows the path of least resitance and if you have gaps around your radiator, they will allow the air around the unit.

What thermostat do you have? A few folks try to run with no thermostat or just a restrictor. At high rpm, the coolant can be running through the system too fast to properly cool. I use a 160 degree with three 1/8 holes in it to release air and provide a little presure release should the wife try to haul ass down the road before the thermostat opens. This can cause the impeller blades to bend on the Chyrsler water pump.

Finally, the fans should make no difference at highway speeds. The air flow should be enough on its own to cool your car. David Lee

I had similar issues and that's why I got the renegade kit. I'd have issues if I was creeping in traffic, moving it would stay cool for the most part.

Shrouding may help. Though toasting an engine or warping heads due to overheating is an expensive way to experiement.

I'd be curious to know what the temp was at the *engine* when it was 215 at the radiator with your thermometer. Keep in mind that the coolant is not circulating where you're measuring it. In my experience, I would see temps shoot up even higher once the engine was turned off due to heat soak.

-bryan

Hi Andrew,

Make sure your air flow is gettng to the radiator as mentioned by the others first. if you are still having the problem then it is air in the system. ask me how i know

I had dealt with these issues back after I first did my setup in Texas. Most what everyone is saying is correct. Since your previous trip(s?) had been uneventful it appears to be a blockage problem as was mine. Definately not the fans. As mentioned they SHOULD not be needed at freeway speeds. Airflow could probably be improved upon but since it was ok b4, not necessarily the problem. How old is your radiator? Have you done any work on the cooling system lately? I'm a lil bit embarrased to say.... my blockage was due to overzealous application of silicone......SEVERAL times. Each time I worked on the system.....more silicone. I finally had it blocked so bad it wouldn't cool at all. Unlike most of your setups, mine uses 2" tubing to route the water back and forth. According to experts.....mine shouldn't cool at all ..................Dad

I hadnt had any problems before because I havent driven it this far before! This was a test...

Radiator is new. Griffin aluminum radiator.

I Might have some "blockage" as far as lines go... I was removing the sodder from some of my copper lines and they warped it a tid bit, caused the end to kind of crimp in a tad. That might be the problem, but I dont know.. Have to fix it somehow by expanding it to round.

I can give it a little more air flow going in at higher speeds by forcing the air in more through ducting. I'll do that....

I DO have 2x air outlet with the hole in the hood. I calculated it out... I'll cut the fender wells out a little and see if that fixes the problem.


I dont think that I will toast a new engine at 220... lol


I did have some air gaps.. one big one under the radiator.. but I put a rubber piece of hose in it to close out the gap... Lemme check to see if its still there... lol... Yup still there... Tie wraps held
Dlee where did you get your foam? I want to try it out a little bit.

Thanks guys. any more ideas would be greatly appreciated!

Andrew

So what happened at the AX? The car ran cool before.... Any possible kinks in your rubber hoses? Did anything shift? Maybe the system needs to be "burped" again. Did you pick up any soft debris on the freeway? Maybe a cone stuffed into your intake. Are you getting good flow if you take off the fill cap? (only remove if the engine is stone cold)

This doesn't sound like a slow degrade of the system, more of an event.

Good luck and keep us posted.

Eric

More thoughts on this... maybe the waterpump belt is slipping. If the engine was revved hard with the t-stat fully closed (seems unlikely after your drive there) you can damage the impeller.

Eric

Bleed and then bleed some more, air pockets are nasty...

Andrew, my foam came out of a computer shipping crate. Grey stuff and rather dense. You can get similar material at some fabric stores, but it will be tan. Cut a bit oversized to wedge it in position and then spraybomb it black or grey. If you drive through a load of water, you might pull it to dry out so it doesn't promote rust. I know you said that you put a piece of hose under the radiator, but you should make every attempt to seal all sides (top and bottom) very well. I saw your setup on your build thread but don't recall whether you have a piece of foam sealing the top of the radiator to the hood. Maybe you were using an aluminum shroud? David Lee

Lemme put it this way...

I was NOT working the engine hard at the autox...

Just watch my video... listen for the engine to hit the cam... It doesnt happen often.. lol


Nothing happened to the engine at the autox. I was 1/2 throttle at most of the straights and coming out of the corners. I didnt have enough TIME to roll onto the throttle all the way because of gettin up to speed to fast...

Im pretty sure that the T stat was open.. I was in the first run group.

Nothing was amis on the car driving home asside from the water temp SLOWLY getting hotter.

Andrew

I cant really "bleed" just open the cap and add water till its full.

besides it just comes out onto my overflow tank anyways.. I said that I checked the overflow tank and it was 2 in of coolant in it... I had 1/2 in before the trip.

Andrew

Mine comes and goes. Biggest problem is air pockets. But 50/50 coolant water mix boils at around 260 @ 15lbs pressure, so 220 or 230 is no real issue as it leaves the engine.

Where is your temp gauge sender? I have two gauges, one as it leaves the engine (between the exhaust ports) and two as it leaves the radiator. Mine usually runs 220 @ one and 165 @ two. I'm going to add a 2 gallon expansion tank in front of the 'firewall' for a little more reserve.

When you bleed ths radiator Raise the front of the car up at least a 18 inches off the ground.
This will get all the air out.
Thnis is a trick I learned dealing with Panteras.

I just love that all of these water-cooled guys have so many temp sensors.

I wonder, Andyrew, since you live in the Central Valley (generally a hot place), if air temp isn't causing some of your problems. It was probably cooler in the morning when you went to the AX than it was when you were driving home. Perhaps your system is just marginal enough that you'll have more problems as air temps rise into the rather brutal summertime weather there.

However, since your outlet temp is well below the thermostat temp, it sounds to me like the system is working fine so far. You might want to try to rig up an in-dash temp gauge with the sensor at the rad outlet, as well as the gauge you have now, which I presume is as it's leaving the engine to the rad.

Andrew,

I'm just thowing random ideas, so don't take my questions personally.

Is your overflow tank the white tank on your fender? If so, is the hose positioned so that the radiator will pull fluid when it cools off? If the overflow hose can pull air, it will introduce air pockets every time you heat cycle the system.

Sorry, I don't know more about your car, maybe I'll do something else for a while....

Eric

When your system heats up and the coolant expands and pressurizes, this naturally forces coolant into the overflow tank. After it sits for a few hours and cools, the reverse happens and a slight vacuum occurs to draw coolant back in from the tank. But at this time your radiator hoses are still flexible and if there are any sharp bends that's when a hose might want to kink or partially collapse. So that's what Eric brought up might be a good thing to check, unless the outside air temp went up a lot.

The radiator is really too low to properly keep the whole system free of air. The best place is above the engine which is the highest point in the system. Raising the front of the car is a good idea for the initial air bleed, but over time, there may be air pockets form again which will not get drawn out with the expansion tank at the radiator.

The angle your radiator sits at it appears you have a upper hose that is higher than your side tank. It also appears to be higher than your surge tank.

Your system could be air bound at that hose.

Or your "T" stat could be stuck open allowing the coolant to circulate too fast. What type of radiator do you have?

I use a double pass "Howe" and my surge tanks is mounted higher than my cylinder heads. Like Dad Roberts I also use large tube to transfer the coolant.

You may try the jack up and bleed method suggested in other threads.

BTW: I drove through Chicago stop and go traffic for 3 hours without my fans in 80 degree heat. I think I was at 195 for a while.
I think I actually need a damper on the intake air to bring my engine temp up on the freeway. Runs at like 180.

Andrew, now that I see the pictures of your setup, I believe an air pocket is the issue. Measure the height of your thermosat housing to the ground and compare with the top of your radiator. I bet it is about 4" higher. What I would suggest it use a blanking cap on top of the radiator and put a pressure cap in the hose that comes off the thermostat housing. Relocate your (volvo I think) overflow to the engine compartment area. Now you have a cap at the highest point of the system for easy air bleeding. You won't have to jack up the car. Fill the system until the front cap overflows and then cap it and continue to fill at the thermostat cap.

Not really a plug, but David at Desert Hybrids has the in line unit with filler neck or you can buy one from Summit or Jeggs.

David Lee

I cannot guess what your specific solution is, however I would consider incorporating a surge tank, which is not the same as an overflow tank. I've used them on race vehicles to great success, an will use one in my V8 conversion as well (good as gold, as far as I'm concerned). The majority of trapped air will accumilate there, and not get recirculared into your system. The referenced link suggests routing a line from the top of the radiator, however there are alternatives that can yeild equally good results.

Read this: http://www.crracing.com/apparel/jackets.html

BTW, I would suggest you should read the other tech stuff on ductwork. The last paragraph is particularly noteworthy.

Andy

QUOTE (andys @ Apr 6 2005, 12:02 PM)

I cannot guess what your specific solution is, however I would consider incorporating a surge tank, which is not the same as an overflow tank. I've used them on race vehicles to great success, an will use one in my V8 conversion as well (good as gold, as far as I'm concerned). The majority of trapped air will accumilate there, and not get recirculared into your system. The referenced link suggests routing a line from the top of the radiator, however there are alternatives that can yeild equally good results. Read this: http://www.crracing.com/apparel/jackets.html BTW, I would suggest you should read the other tech stuff on ductwork. The last paragraph is particularly noteworthy. Andy

You bet. Plastic puke tank is not pressurized, it just keeps things tidy. A half full surge tank high in the system is the way to go. I have a small one in the engine compartment now. It's high enough, but sits above the exhaust manifold. I'm thinking front mounted is the way to go. Would end up in the airflow behind the fan, too.

Lots of great idea's guys!

I'll try to get an answer for them or a commment.

First My temp guage sensor is as it leaves the engine. Therefore the hottest point of the engine.

My "bleed" system is in the back. where my fill is. I jack up the back of the car, let it burp, jack up the front, let it burp air, then repeat and fill when it is level.


Also my overflow tank that is used is the one pictured in the engine bay, it has a tube that runs to the bottom of the tank for drawing fluid.This radiator cap is 18lb and the front is 20lb. I dont want to take the front on and off therefore thats the higher pressure cap. The overflow is just there "because".

James, yes, I do want to put some more temp guages readable in the car to be able to tell when the setup is not running efficiently.

Guy, Like I said my expansion/overflow is in the back. My lines with bends are made from copper, so hopefully they wont kink!

Andy, I will very much look into a surge tank, I think its a good idea and something that will help with my overflow problem.

I hope this clears up some of the questions you guys have, and I hope you have more possible idea's..

Thanks guys!

BTW, I think I know the cause to my overheating....

Just not how to fix it... lol

Opened up my radiator cap to take a peak, noticing that the overflow tank was full..
Yup lots of room for water in the system, basically 3/4 the overflow tank should fit in their...

You guys said that it 'should' suck the stuff back in.... no... It didnt.

My guess is that after autoxing and getting the engine up to 200 maybe 210 for about 3 mins, then shutting it off caused it to purge some of the water out of the system, then driving home it didnt get cool, thus causing it not to be able to suck the water back INTO the system, leading to an air pocket in the system. THUS causing my overheating problem.

So.... Why did it not suck it back in?

I drove it for the next couple days to school, noticing water temps rising quite fast...
Now I checked the overflow tank and noticed the air pocket...

Simple fix... but how do I prevent it?

With this sump tank thing??

Andrew

I've had this problem before.. when it cools, it WILL suck SOMETHING back into the system. Air is easier to suck in than water, so that gets sucked in if there is any way. It could be anything from a loose hose clamp, to a cracked block. Do you have clamps on your overflow hose? That was the problem on my mustang.. I could hear the bubbles being drawn in as it cooled down.

I think that the "sucking back" only occurs when the car goes cold, i.e. not running. If you observed the lack of coolant though the cap in your engine compartment, it should have pulled from the overflow bottle. This happens pretty slow, so a very small gap (connection, cracked hose) could pull air, not coolant. Your filler looks like its pretty high in the system, so I wouldn't expect that to be a problem, though I guess that any air pocket near the cap might keep the system from sucking. As more air goes into the system, the effects get worse, car heats up more, spits more coolant, and will pull even more air each heat cycle.

On my car, the coolant filler tank (RH's term) is mounted up on the firewall, as the highest spot in the system. This allows me to run the car cold with the cap off to burp the system. There is also an air bleed on my radiator to clear any pockets at the other end. Though I've checked a couple of times since the car went back on the road, I haven't observed any air in the system at either end. Renegade sells their filler tank for $75.

You may not have an issue with your system, if you're experiencing these symptoms after first conditions, i.e. first long freeway drive, first a-x, etc. I would fill the sysytem, tighten your connections and see if it's still happening, you might just be collecting the various small pockets from throught the car, reducing the flow and getting the snowball effect noted above.

If it's still a problem, consider the extra tank in the system.

Good luck,
Eric

I do NOT have any clamps on the overflow lines.

I will check to see if they are "air tight" but I doubt it.

I'll clamp em down and see how it goes...

Thanks guys.

BTW Eric, could you post a pic of your system you are describing? I want to redo the cooling system (hose wise) and wouldnt mind spending 200 bucks for some nice stuff...

Andrew

The car's getting tuned right now, but I'll post pics as soon as I get it back. The cooling system is "stock" Renegade, installed by the guys at their shop. Ian should be running the same parts...

Eric

QUOTE (ewdysar @ Apr 6 2005, 05:03 PM)

The car's getting tuned right now, but I'll post pics as soon as I get it back. The cooling system is "stock" Renegade, installed by the guys at their shop. Ian should be running the same parts... Eric

I sh!t when my car got to 200 once.... it was after filling the system and I had a huge air bubble. It' never goes over 190...my t-stat takes its time opening up, then it's 180 from there on.

I installed the Renegade setup on my own. I am also using the same style bumper as the Renegade flagship, "Peel." I need to shroud the air scoop to my radiator a little better. Right now air is going in the bumper and under the car, but seems to do just fine during street driving.

There's a good shot of my car from the front in the "Headrage BBQ pics" thread.

Ok, went out to check the overflow line....

Like glued on.. I'd say it was air tight enough. The other end of the line was IN the tank, so it would just suck in from the bottom of the overflow.

Is it possible that it would have sucked in air from when a car went into a corner??

I thought that that only happened when the car cooled off...

QUOTE (Andyrew @ Apr 6 2005, 08:04 PM)

Ok, went out to check the overflow line.... Like glued on.. I'd say it was air tight enough. The other end of the line was IN the tank, so it would just suck in from the bottom of the overflow. Is it possible that it would have sucked in air from when a car went into a corner?? I thought that that only happened when the car cooled off...

You are right, while the engine is running and up to temperature, cooling system is pressurized and will not draw water from expansion tank.

I went through water cooling v8 914s a few summers ago here in Georgia and learned allot. Much of what I learned has been touched on already but I'll add my .02

First of all, your not too hot at highway speeds yet, but under these conditions you should not see a increase in temperature as compared to what you see when in traffic. I had the exact thing happen with a full Renegade system and found one of the smaller hoses from water pump had a small kink that restricted flow only at high speed. Our systems may be different but I had a tight area where hose left water pump and came pretty close to headers prior to entering front of block. I wrapped hose with kevlar to prevent contact with headers and this is where the kink was found.

My car was first put on the road when outside temperatures were about 80F. All seemed fine until outside temp. rose to about 90F. This is when all my cooling system flaws started to show. RH first recommended a different thermostat (I just picked up a run of the mill chevy 180F from my FLAPS). I changed to a Mr. Gasket "high flow" AND drilled the three 1/8" holes. Compare this to a normal thermostat and you will see what they mean by "high flow". This gave a immediate improvement but as time went on and outside temperatures began to rise, I slowly started seeing my highway temperatures rise again. It would sit at 180F for 20 minutes or so but would start to cycle from 190 to 220 as the "heat soaking" set in.

Further conversations with RH revealed I did not understand the burping procedure. This is how Renegade does it:

1. car stone cold and overflow tank filled to "cold" level

2. remove fill cap (they discourage the use of release lever type you are using and recommend 16lb. cap with their system) I did not ask about details concerning the flip top cap, just took their word and suspect they had problems from these in the past.

3. have jug with water available and start engine. Watch water flow at fill point (won't happen if you don't have 1/8" holes drilled in thermostat). Add water if level goes down. Continue watching water flow and air escape from this port and have radiator cap handy. Note: with your fill port having a extra 90 degree bend, I'm wondering if filling to top would prevent air from escaping. I'd suggest just filling to level that would allow air to escape from horizontal run of cooper pipe.

4. As coolant temp. approaches 150F or so, water will start to expand and you will have to install radiator cap.

5. Add an extra inch or two of water to expansion tank and go for a long drive at highway speed.

6. When you arrive back home, turn engine off and watch cooling temperature. When it (engine temperature)reaches about 170F, open petcock at top of radiator to allow removal of air bubbles.

Now the important part! Repeat what you just did two more times, letting the car fully cool down (4-8 hrs.) in between burping sessions. Overnight will net best results.

At this point, air should be removed from system and you should have a stable amount of water in cooling system. Mark the level in your overflow tank when car is completely cooled. If the level changes (checking only after allowing to cool over night) you have another problem.

A leak in the line from overflow tank will allow air back in to system everytime car cools down. If you suspect a bad overflow tank, your FLAPS sells a really nice piece for about $12. The one I use has a fitting on bottom of tank for water/air to and from tank. The top fitting is only to vent tank and overflow in the event you have a boilover.

The above procedure needs to be performed any time you drain the cooling system (replace hose, water pump etc.)

After using the proper procedure, I was able to maintain constant 190F cooling temperatures in 90+F weather with the a/c blowing, all attached to a stock geared 901/400hp small block. I've made several 2-3 hour trips running 80 mph without any problems.

John

Andrew,

Looking back at your photos, I noticed a overflow tank in front trunk. I tried one of those during my troubleshooting woes and saw no improvement. Since you have no place to purge air from radiator (while performing burping procedure), I suggest using a flip type radiator cap installed on radiator and use this as a point to remove air at front of car. That's the easy way out if the flip top cap does not leak. The best approach would be to install a petcock and eliminate radiator cap fitting.

If you install a flip top cap, get the highest pressure unit you can find. Your cooling system will be protected by the cap in rear.

I've attached a pic of overflow tank I found in my local area. This is the large size. There is one about 1/2 this size. Note: clear hose with anti freeze color goes to bottom of tank. Black hose is overflow. Attaching bracket comes with tank.

John

I may have missed something here......I believe you said that the hose going in the top of your coolant recovery tank ( in the pic )goes down into the bottom of the tank? A normal coolant recovery tank has a fitting on the bottom of the tank for this so there is no chance of it suckin air unless it's low. There should be a hose coming off the tank cap for venting and overflow, if necessary. I also don't see that top hose. I could be wrong but if you only have the one hose it can't be functioning properly. I have been running a cheap PepBoys unit for 30,000 miles with no problems. Hoses routed as described above. Let me know if this helps?..............Dad PS.......I see Johns' is as mine is

John's setup looks identical to mine. The small octagonal fill tank from RH, mounted high. I've got the same overflow tank mounted in the same place with the cap overflow hose going to the bottom fitting as shown. The burping process is over a couple of days (which I followed) yielded the same consistant cooling results.

Ahh, the joys of a custom car...

Eric

QUOTE (ewdysar @ Apr 8 2005, 10:57 AM)

Ahh, the joys of a custom car...

Absolutely.
Everytime he complains, I tell him to go buy a Honda. That shuts him up
Of course, when it's not running, he drives one of my cars, kid's got it rough..

Dad-- I didn't know you had a v8 car! We'll have to compare Dad notes..

Looks like we'll need to reevaluate a few things. The overflow tank is a good place to start. Then look at the front cap. I suspect that no tank is needed there, just a bleed valve. We're running 1" lines front to back in and out.

I believe it's all a matter of getting the air out off the lines. And making that happen easliy in case of a quicky repair and then a drive home.

So here's what I'm gleaming from all your great suggestions (let me know if I'm wack...<- like my slang?)

1) Install a real overflow tank in the engine compartment. (the highest point )
2) Remove the front tank (it's not really doing anything and it's pretty low compared to the tank in the engine compartment.)
3) rig a bleader valve at the top of the radiator. Possibly change the cap to a solid with a bleeder valve.
4) check for kinks or other flow problems. (this should be #1)
5) possibly dump the homemade fill tube in the engine compartment and get something like the hex shaped doodad...
6) check the thermostat for proper function. (Holes are drilled already)

I'm not sure if we can tell if there is air in the system. So this may be the guessing game.

One thing that bothers me is that I can't run without the radiator cap on without taking a shower. The waterpump shoots water out like a firehose. In the good old days we used to leave the cap off and test for flow and temp changes in the coolant.

I've rambled on long enough. Thanks for all the suggestions. let me know if I'm way off base.
Thanks.
Dan (Andyrews Dad).

I think I have it figured out! Is there any fluid in the front overflow tank? Both radiator caps have a valve that lets overflow back in as it cools. Even if there is fluid in both tanks when you start, since one is a higher pressure cap it won't ever let any out.. but it WILL let it IN, so that tank will eventually empty. Once it's empty, it's easier for the vacuum to pull in air at the front cap than coolant at the rear tank.

Andy,

I told you that thing was possessed by the devil.

Seriously, sounds like a vapor locked cooling system.

Rob

Dan,

I agree with your approach with just a few exceptions. If your going to pull the thermostat, I'd replace it with the Mr. Gasket piece (Summit part #MRG-4364 @ $8.95 ea.) This thing does make a difference.

If you can't run the engine cold without a free shower, this tells me your fill port is connected between water pump and engine block. The RH approach is to have it connected on the discharge side of engine (between thermostat housing and return hose back to radiator). The difference is that when engine is cold (thermostat closed) you can run with cooling system open since the only water flow through your fill port is what passes the 1/8" holes. The radiator cap is installed as the water expands and thermostat begins to open. You'll have better success in removing air from system if you route it the RH way. I'm not 100% sure that you are connected the way I assumed since the picture is so dark where the hose connected to fill port routes. If in fact it is connected to thermostat housing, it must be as you suggested, the side mounted fill port that is causing the free shower. But, it still looks puzzling since the elevation/location of opening does not look that low. Almost sounds like thermostat is stuck open???

I'll add a couple of pics to clarify. Note: fill port- larger black hose on left is from thermostat housing. Hose coming out the bottom of fill port is return line back to top of radiator.

John

Petcock location at top of radiator (drivers side)

Avoid kinks like this at all cost. This is one of the most common kink locations in v8 converted 914s. This just happens to be on the suction side of pump and the kink gets worse at higher rpm.

John

Wow Royce! You could be onto something. Is anyone else running 2 pressure release radiator caps? The differest pressure caps "could" be the root cause on this problem.

So the test would be: fill and burp the system as well as possible. Then fill both overflow tanks 1/2 full and mark the height. Drive the car and check the level each time you start the car. If the coolant is "magically" transporting itself to the rear tank over time, you've nailed it.

If this is the issue, removing the front overflow tank would make the problem worse.

The fix would be a fixed (non-pressure release) cap on the radiator.

Andyrew and Dad, please do the test before the other changes, I'd love to know if Royce is right....

Eric

John,
We are connected between the thermostat housing and the radiator inlet. It seems odd to me that it sprayed me. (made for a good laugh though). We'll look at the thermostat issue.

Eric,
I see what Royce is saying. We'll check this out. It would certainly be possible.

Thanks again!
Dan

Hooo doggies...

Way to much to grasp!!!!

Ummm.. were to start..

Royce.. Very good observation, I have never put any water in the front tank at all. Therefore, I will fill the tank up, mark it, and drive the car, if it starts to pull from THAT tank, I will cap off that overflow system by using a fixed radiator cap like Eric suggested.

Rob, I've never heard of a vapor locked cooling system... lol

John, I am routing it the RH way... The fill is in between the Thermostat on the top of the engine, and the radiator. One observation that I think MIGHT make a difference is that I am running a very large hose on the thermostat (standard sbc size) then I am adapting it to a 1in hose with copper piping/reducers. I did sort of kink the ends in a tad bit trying to clean up my welds a little bit (now currently brazed on... not by me.. lol) but I didnt think it was that much of a kink, so I installed it. Im considering taking it out and 'unkinking it'

I do not have a petcock on my radiator. But I am considering putting one in it...
Especially if I have no way of bleeding air from it.

Thanks guys! I wish I could start on this now, but I have work in half an hour till 630...
But i'll try and do all those things then.

Andrew

Funny, I tried the renegade way of bleeding the system...

Didnt move much water till about half a minute into the run... then it moved a tad, and spirted water every couple seconds... Then the water started to fizz... fizz started to overflow.. I put the cap on and shut the system off..

We'll see what the level is at in a little bit...

Andrew

Took it for a drive. got it to 200 with no fans driving around for about 5 mins.. kinda stayed at 200 for a while with no fans... switched on the fans, got on it hard for a couple of gears and drove it around a little more and parked it.

Nothing in the overflows (cept what I put in them)... So cant really test if it sucks in from the front or not...


Maybe I need to get it hotter??


I think I got all the air out of the system... Its now a matter of keeping it out...

QUOTE (Andyrew @ Apr 9 2005, 08:56 PM)

Took it for a drive. got it to 200 with no fans driving around for about 5 mins.. kinda stayed at 200 for a while with no fans... switched on the fans, got on it hard for a couple of gears and drove it around a little more and parked it. Nothing in the overflows (cept what I put in them)... So cant really test if it sucks in from the front or not... Maybe I need to get it hotter?? I think I got all the air out of the system... Its now a matter of keeping it out...

You need to operate the car longer at highway speed to get things hot and allow air bubbles to work themselves out of trapped pockets. The key here is to produce heat by operating at higher rpm than what you would see while cruising AND higher RPM will give you the proper circulation needed to move air bubbles. You can replace highway speeds with track type driving.

If your cooling system is full when cold, you should see at least 2 inches of coolant added in your recovery tank after performing the above. As mentioned earlier, RH uses a 16lb. cap. Your 18lb. rear and 20lb. front cap may require longer drives before allowing system to burp into recovery tank.

If you had air in the system to start with, the short procedure performed did not remove it. It takes time (a couple of days) to really get it all.

Fans should turn on at 180-190 (performed automatically at 187F via a thermoswitch in radiator using the RH radiator) and turn off at 170F. Keep in mind this is as measured from radiator. The point is, you don't want the fan(s) to turn on too late or your system will be playing catchup. In other words, once the heat soaking sets in, your cooling system may never be able to catch up. Note: above 45 mph or so, your fan is not needed.

If you plan to remove all the air from system before making any other changes, I'd recommend at least changing out forward radiator cap with the flip top release so you can remove air from this area of system. Renegade's burping procedure works, you just have to perform all the steps as outlined on previous post.

Good luck,

John