Block Test Kit Question
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Instructor
Joined: Mar 2012
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From: NH
Block Test Kit Question
I suspect I have a possible slight leak in my head gasket on a 93 LT1. I can smell coolant on the passenger side of the block, but I have not been able to find a leak anywhere else. It also sounds like it has a slight stumble or miss. I did the coolant system leak down test and it passed, but it occurred to me that if the thermostat was closed, I wouldnt be testing anything in the block. I saw from another post something about the block test kits you can get from Autzone, etc so I picked one up and went to use it hoping I could get it done real quick. Compression was good on all cylinders I was able to get my gauge into, can't get at 3 of them with my gauge.
The issue is, and this is probably a dumb question, where am I supposed to put it since it cannot attach right to the radiator? I imagine it goes on the reservoir, but no matter how much I try to syphon off, it just kept filling with more coolant. As soon as I started the car up, the reservoir just filled up until it would run to the overflow tank line. Am I supposed to drain the radiator from the petcock instead of trying to suck it out with a turkey baster? How much do I need to drain so the resevoir doesnt just fill up again? Can this test be done from the overflow tank? Thanks.
The issue is, and this is probably a dumb question, where am I supposed to put it since it cannot attach right to the radiator? I imagine it goes on the reservoir, but no matter how much I try to syphon off, it just kept filling with more coolant. As soon as I started the car up, the reservoir just filled up until it would run to the overflow tank line. Am I supposed to drain the radiator from the petcock instead of trying to suck it out with a turkey baster? How much do I need to drain so the resevoir doesnt just fill up again? Can this test be done from the overflow tank? Thanks.
Safety Car
Joined: Apr 2005
Posts: 3,624
Likes: 431
From: Dale City VA
I suspect I have a possible slight leak in my head gasket on a 93 LT1. I can smell coolant on the passenger side of the block, but I have not been able to find a leak anywhere else. It also sounds like it has a slight stumble or miss. I did the coolant system leak down test and it passed, but it occurred to me that if the thermostat was closed, I wouldnt be testing anything in the block. I saw from another post something about the block test kits you can get from Autzone, etc so I picked one up and went to use it hoping I could get it done real quick. Compression was good on all cylinders I was able to get my gauge into, can't get at 3 of them with my gauge.
The issue is, and this is probably a dumb question, where am I supposed to put it since it cannot attach right to the radiator? I imagine it goes on the reservoir, but no matter how much I try to syphon off, it just kept filling with more coolant. As soon as I started the car up, the reservoir just filled up until it would run to the overflow tank line. Am I supposed to drain the radiator from the petcock instead of trying to suck it out with a turkey baster? How much do I need to drain so the resevoir doesnt just fill up again? Can this test be done from the overflow tank? Thanks.
The issue is, and this is probably a dumb question, where am I supposed to put it since it cannot attach right to the radiator? I imagine it goes on the reservoir, but no matter how much I try to syphon off, it just kept filling with more coolant. As soon as I started the car up, the reservoir just filled up until it would run to the overflow tank line. Am I supposed to drain the radiator from the petcock instead of trying to suck it out with a turkey baster? How much do I need to drain so the resevoir doesnt just fill up again? Can this test be done from the overflow tank? Thanks.
The thermostat won't make any difference because the block gets it's coolant from the lower radiator hose.... the thermostat only controls what coolant gets out of the engine (NOT what coolant enters).
You should not have to remove any coolant from the surge tank to perform the test..... if it's pushing the coolant out of the surge tank into the overflow tank, then you have the wrong adapter and it's not sealing the overflow port off in the filler neck.
Will
Last edited by rklessdriver; Apr 4, 2013 at 08:26 AM.
Thread Starter
Instructor
Joined: Mar 2012
Posts: 170
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From: NH
I am talking about the block test kit where you attach the tester to the coolant system and fill it with and indicating fluid. You can suck air through the fluid and it will change color if there is combustion gas present in the coolant system.
I have already done the pressure test of the coolant system and it held pressure. I can still smell coolant though after the car has been running so it is driving my crazy trying to figure it out. If your saying that it would also test the block, then I am evenmore confused now. If the issue is temperature related, how would I find it? Can the pressure kit be used with the coolant system at operating temperature? I did the test cold previously.
I have already done the pressure test of the coolant system and it held pressure. I can still smell coolant though after the car has been running so it is driving my crazy trying to figure it out. If your saying that it would also test the block, then I am evenmore confused now. If the issue is temperature related, how would I find it? Can the pressure kit be used with the coolant system at operating temperature? I did the test cold previously.
Safety Car
Joined: Apr 2005
Posts: 3,624
Likes: 431
From: Dale City VA
I am talking about the block test kit where you attach the tester to the coolant system and fill it with and indicating fluid. You can suck air through the fluid and it will change color if there is combustion gas present in the coolant system.
I have already done the pressure test of the coolant system and it held pressure. I can still smell coolant though after the car has been running so it is driving my crazy trying to figure it out. If your saying that it would also test the block, then I am evenmore confused now. If the issue is temperature related, how would I find it? Can the pressure kit be used with the coolant system at operating temperature? I did the test cold previously.
I have already done the pressure test of the coolant system and it held pressure. I can still smell coolant though after the car has been running so it is driving my crazy trying to figure it out. If your saying that it would also test the block, then I am evenmore confused now. If the issue is temperature related, how would I find it? Can the pressure kit be used with the coolant system at operating temperature? I did the test cold previously.
Yes when you pressurize the cooling system it pressurizes the radiator, engine block and cyl heads all at the same time.... So if no leak, that's not your problem.
However - Since you only smell coolant when it's hot and the system has so far pressure tested good, I would say you have a weak radiator cap which is allowing coolant to vent/recirculate into the overflow tank too early once it's hot.
Go and buy a new Stant 16lb radiator cap and I bet that will take care of the smell.
The Exhaust/CO2 test for cooling systems is something different and you can just put it in the surge tank and get a reading.... no need to get it in the block.
Will
Melting Slicks
Joined: Aug 2008
Posts: 2,082
Likes: 50
From: Palmdale CA
I am talking about the block test kit where you attach the tester to the coolant system and fill it with and indicating fluid. You can suck air through the fluid and it will change color if there is combustion gas present in the coolant system.
I have already done the pressure test of the coolant system and it held pressure. I can still smell coolant though after the car has been running so it is driving my crazy trying to figure it out. If your saying that it would also test the block, then I am evenmore confused now. If the issue is temperature related, how would I find it? Can the pressure kit be used with the coolant system at operating temperature? I did the test cold previously.
I have already done the pressure test of the coolant system and it held pressure. I can still smell coolant though after the car has been running so it is driving my crazy trying to figure it out. If your saying that it would also test the block, then I am evenmore confused now. If the issue is temperature related, how would I find it? Can the pressure kit be used with the coolant system at operating temperature? I did the test cold previously.
There are other symptoms that may occure when a gasket is leaking; Recovery tank level varies greatly between cold/Hot engine, recovery tanks is blowing bubbles, Analog gauge fluctuates between normal and Hash marks, engine stumble in High gear, excess steam at tail pipe, spark plug has a whitesh steam clean look to it.. etc.
It would be a good idea to get the equipment needed to perform a Compression test.
Thread Starter
Instructor
Joined: Mar 2012
Posts: 170
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From: NH
Performed the test with the indicating fluid and got no color change. Then I went and got the leak down tester, only found a small leak on lower radiator hose which I just tightened the clamp during a test at cold. I started the engine and let it run to hot with the tester attached. It held pressure and the needle didnt do any jumping so I think the gaskets are good. The cap would only hold pressure up to the minimum in the zone I was in, so I am think it may just be a radiator cap for the coolant smell as rklessdriver stated. If that doesnt work, then I am just going to deal with it!
The miss at idle could be as simple as needing a tune (has a lot of mods to intake and exhaust), but I am going to do some cylinder leak down tests and check valve adjustments before I pony up the cash for a Moates system and get into learning to tune a Speed Density system.
The miss at idle could be as simple as needing a tune (has a lot of mods to intake and exhaust), but I am going to do some cylinder leak down tests and check valve adjustments before I pony up the cash for a Moates system and get into learning to tune a Speed Density system.
Safety Car
Joined: Apr 2005
Posts: 3,624
Likes: 431
From: Dale City VA
Glad you got it figured out and its nothing serious.
Will
Will
Performed the test with the indicating fluid and got no color change. Then I went and got the leak down tester, only found a small leak on lower radiator hose which I just tightened the clamp during a test at cold. I started the engine and let it run to hot with the tester attached. It held pressure and the needle didnt do any jumping so I think the gaskets are good. The cap would only hold pressure up to the minimum in the zone I was in, so I am think it may just be a radiator cap for the coolant smell as rklessdriver stated. If that doesnt work, then I am just going to deal with it!
The miss at idle could be as simple as needing a tune (has a lot of mods to intake and exhaust), but I am going to do some cylinder leak down tests and check valve adjustments before I pony up the cash for a Moates system and get into learning to tune a Speed Density system.
The miss at idle could be as simple as needing a tune (has a lot of mods to intake and exhaust), but I am going to do some cylinder leak down tests and check valve adjustments before I pony up the cash for a Moates system and get into learning to tune a Speed Density system.
