Puzzling Coolant Issue
Thread Starter
Racer
Joined: Oct 2010
Posts: 257
Likes: 7
From: Haslet texas
Engine. 3.875 in stroke , 7 in rods, -4cc flat top pistons, 4.060 bore, all forged. Le 290/300 advertised duration 110 lsa. Dart pro 1 180cc heads, 58cc combustion chamber. Ported le intake, 58mm tb, pcm for less tune.
I asked a well seasoned mechanic, whom did my machine work and owns a shop, about combustion gases getting into coolant. He dismissed it due to the fact, that it would happen all the time. I have had this issue before and the rising temperature will begin at analog sensor on the block instead of the warer pump sensor like it is doing now
I asked a well seasoned mechanic, whom did my machine work and owns a shop, about combustion gases getting into coolant. He dismissed it due to the fact, that it would happen all the time. I have had this issue before and the rising temperature will begin at analog sensor on the block instead of the warer pump sensor like it is doing now
Last edited by JAKE-SON; Nov 10, 2012 at 06:25 PM.
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
I can't say that I disagree and it is a logical comment from your mechanic. But it is an assumption and saying that, or, "this item never goes bad" is a way to go in circles or off in a tangent. If you have other ideas of the problem then peruse them. But if you have no other place to go, then it's time it get **** and keep an open mind and check things that you might have eliminated before.
Le Mans Master
Joined: May 2006
Posts: 9,226
Likes: 9
From: Irvine Ca
I hate to make such a rudimentary suggestion....but check the radiator cap to see if it is holding pressure......when your system hits 212° the water starts to boil at atmospheric pressure. If it is pressurized the system does not boil (spews out into the overflow tank)
Try the cap and see if this is it....
The only reason I mention this is that I had a real scare just two weeks ago from a new cap from O'Rielleys. People said the head gasket was blown....it was just the cap not holding pressure....and it didn't act up until hot days.......my car runs cool.
Try the cap and see if this is it....
The only reason I mention this is that I had a real scare just two weeks ago from a new cap from O'Rielleys. People said the head gasket was blown....it was just the cap not holding pressure....and it didn't act up until hot days.......my car runs cool.
Thread Starter
Racer
Joined: Oct 2010
Posts: 257
Likes: 7
From: Haslet texas
I have a extra cap that has maybe 20 miles on it. I will go ahead and put that on and hope that is the problem. I will wait till the problem occurs again and see if the fans are off or it the top radiator hose is cold, guessing that will be able to narrow down my problem some more. Thanks for all the help and suggestions, will follow up when/if the problem occurs again.
Very Respectfully,
Ryan M.
Very Respectfully,
Ryan M.
Thread Starter
Racer
Joined: Oct 2010
Posts: 257
Likes: 7
From: Haslet texas
it's back
Welli drove it around for two weeks with no provlem, third week i replaced the cap, even though there wasnt a issue. On the fifth week, today, the problem occurred again. Temp bega to rise 1 degree every 10 seconds on digital gauge, the analog gauge was about 40 degrees behind digital. Both fans were on thr entire time, coolant did bubble over as well.
Thanks for any help
Ryan M.
Thanks for any help
Ryan M.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Disagree with your mechanic
A head gasket or crack in the head can be temp sensitve to when it decides to open up and let the gases in had it happen to me.
You ever have those magnafluxed?
What do your plugs look like? Any real clean ones when you have this happening?
A head gasket or crack in the head can be temp sensitve to when it decides to open up and let the gases in had it happen to me.
You ever have those magnafluxed?
What do your plugs look like? Any real clean ones when you have this happening?
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Melting Slicks
Joined: Aug 2008
Posts: 2,082
Likes: 50
From: Palmdale CA
Welli drove it around for two weeks with no provlem, third week i replaced the cap, even though there wasnt a issue. On the fifth week, today, the problem occurred again. Temp bega to rise 1 degree every 10 seconds on digital gauge, the analog gauge was about 40 degrees behind digital. Both fans were on thr entire time, coolant did bubble over as well.
Thanks for any help
Ryan M.
Thanks for any help
Ryan M.
Ryan, Was it you who had a problem with stop leak a while back? I seam to recall an Incident with Congealed Stop Leak "Globs" plugging up a Radiator.. If so; you may have some of this stuff forming clogs, or blockage's from time to time.
Thread Starter
Racer
Joined: Oct 2010
Posts: 257
Likes: 7
From: Haslet texas
Yes it was me with the stop leak globs. I dissassembled the engine down to the pistons, crank and rods only in and cleaned out all the gunk. I did change the radiator right before the engine pulll, but did not remove the radiator and clean it after i cleaned the block. The thought did cross my mind if there was a phantom piece flowing around causing the blockage. Yes, the temp at digitial is always higher than my temp on analog, at least 20 degrees behind on normal days. Digital read 180-190 and the analog is between its starting point and 185
Drifting
Joined: Mar 2012
Posts: 1,492
Likes: 61
From: New Jersey
Before you do anything else, you should do a complete flush of the engine, radiator, heater core, surge tank and overflow. Check all of your hoses also. Now that it seems you had a prior problem with sealant globs, there is a good chance some of that is still floating around and causing problems.
Instructor
Joined: Feb 2004
Posts: 134
Likes: 0
From: Snellville GA
Sorry to hear your issues. Mine turned out to be a crack cylinder wall to water jacket building pressure in cooling system. Sleeve was corroded from inside. Stop leak slowed it way down until 1 hot day. Then I blew the press tank and following that the radiator. Now looking at a new block. 383, bored .040 over. Good luck. Recommend you pull the heads again and look at each cylinder with a small inspection mirror and bright light. After the engine sits a week or two, the water leak area will show tiny traces of rust like a hairline crack. Dave
Melting Slicks
Joined: Aug 2008
Posts: 2,082
Likes: 50
From: Palmdale CA
Ryan, I still don't understand why your heads run cooler then the block, unless there is a calibration error, or something else going on here we don't understand..
But for now, I would Focus on the runaway temperature problem. I personally would remove the knock sensors and push water through the block and observe for any of this stuff coming out.
Secondly, I would remove the radiator and perform a Back flush, It is Conceivably Possible that there are small piece's of this stuff blocking your cross tubes in the radiator, if the piece's are too large to penatrate the tubes, then they will just lay accross them at will, and obstruct the flow. This would explain why the problem is so random.
Third, it is also possible that there are piece's forming around the thermostat.
Just a few thoughts, but concidering the nature of your former problem there could be a connection here...
But for now, I would Focus on the runaway temperature problem. I personally would remove the knock sensors and push water through the block and observe for any of this stuff coming out.
Secondly, I would remove the radiator and perform a Back flush, It is Conceivably Possible that there are small piece's of this stuff blocking your cross tubes in the radiator, if the piece's are too large to penatrate the tubes, then they will just lay accross them at will, and obstruct the flow. This would explain why the problem is so random.
Third, it is also possible that there are piece's forming around the thermostat.
Just a few thoughts, but concidering the nature of your former problem there could be a connection here...
Instructor
Joined: Jan 2001
Posts: 169
Likes: 1
From: In Washington near Portland, OR. Washington
Ok, I've read every post. Starting at your OP where you stated the stat has been replaced a few times I'm not going to suggest it nor state that you should not rule out xyz, or check the fan again, or pull the heads right away.
One post rightly suggested a exhaust gas test.
Rather than shot gun more parts (or same parts) why not
run the gas test?
Do it while car is running normally for a baseline. Then keep the kit with you. Upon next event measure gas.
The results of the gas test will point which way to proceed.
Frustrating I know but hang in there. You'll get it.
One post rightly suggested a exhaust gas test.
Rather than shot gun more parts (or same parts) why not
run the gas test?
Do it while car is running normally for a baseline. Then keep the kit with you. Upon next event measure gas.
The results of the gas test will point which way to proceed.
Frustrating I know but hang in there. You'll get it.
Thread Starter
Racer
Joined: Oct 2010
Posts: 257
Likes: 7
From: Haslet texas
Well problem happened again today. Was holding temp in 180s for a while, then it began to climb Went home and messed around with it a bit, let it also cool and run with cap off and noticed their was no coolant return to fill tank/circulation from the hole that was noticeable. At one point it seemed as if it would overflow, i stepped away for a quick second and when i returned it was back down.Sometimes the bottom radiator hose was hot, other times it felt cool. Opened bleed screw, straight coolant came out. Also touch the radiator when car was at 170, middle was warm, top was cool. Will go out and purchase a combustion tester tomorrow as recommended
Ryan
Ryan
Instructor
Joined: Jan 2001
Posts: 169
Likes: 1
From: In Washington near Portland, OR. Washington
1. water pump impeller backwards (etc)
2. 1/8 hole in T stat
3. reservoir cap
4. blockage
5. ?
If gas is detected then trying to isolate which side is doing it
so both heads don't have to come off.
I hope you're in the first group.
Thread Starter
Racer
Joined: Oct 2010
Posts: 257
Likes: 7
From: Haslet texas
Stat does gave the factory hole in it with the little metal piece in the hole, should I remove the metal piece?
You mean the coolant crossover tube to go between the heafs, yea its on there