Tools for testing head gaskets?

[scott37300]

I'm pretty sure I have a blown head gasket. I have an older combustion block tester, the ones that the blue fluid turns yellow if a blown head gasket. Is the car fails this test and the fluid turns yellow does this mean head gasket 100%? What other tools or tests should I do if any? How about a leak down tester like this, http://www.amazon.com/dp/B000Q6P7GU/?tag=atomicindus08-20 Looking at different ways to test head gaskets and make sure that is my issue. Also using it as an excuse to buy new tools if needed. So what testers do you guys/pros use to find bad head gaskets?

 

[jethro29]

a leak down tester is the best way to determine what's going on in my opinion. although they can be a pain in the *** to get hooked up.

 

[chrisziem]

Do you have coolant in the oil or oil in the coolant? Are there leaks around the head gasket? Does the exhaust put out sweet smoke? Have you done a coolant pressure test? Have you done a compression test?

 

[Wrenches of Death]

I'm pretty sure I have a blown head gasket. I have an older combustion block tester, the ones that the blue fluid turns yellow if a blown head gasket. Is the car fails this test and the fluid turns yellow does this mean head gasket 100%?

No, it could also be a cracked head, or a cracked cylinder block, or it it uses them, a cracked liner. Sadly, there are a number of ways for combustion gases to get into the coolant.

You can run a compression test on each cylinder and hopefully narrow it down to a specific cylinder. You can monitor coolant system pressure with the engine running. This can give you an idea of the severity of the leak.

In the event that the compression test and the appearance of the spark plugs fail to identify which cylinder has the problem then you might want to leave the spark plugs out. Next, with everything at room temperature, make sure that the cooling system is full, and then use a coolant system tester to run the pressure of the cooling system up to it's normal pressure and leave it sit for a while. If it leaks down, pump it back up. If it doesn't leak down, things just got a lot harder.

Next, then tie a small piece of light colored cotton cloth to a thin piece of stiff wire and run it down each spark plug hole and wipe the low part of the cylinder. The wet one will be your leaker.

You have to pull it apart to determine what failed, but at least you know which cylinder to scrutinize.

WoD

 

[soob]

The easiest way I think is to just look for bubbles in the coolant overflow tank. I'm not sure that's a 100% method, but it works.

I don't know if there's any way to really pin down where the leak is, could be gasket, could be warping, could be cracks. You have to pull it apart to find out.

 

[RKSpeed]

WHY do you think you have a blown head gasket?

 

[theoldwizard1]

Leak down tester.

I'll admit it can not tell the difference between a blown head gasket, a cracked cylinder (or liner) or a cracked head, but the last 2 are not as common as a blown head gasket.

If you are losing coolant, you had better do something quick. Hydraulic lock up on start up does not usually cause too many problems but you are likely getting water in the oil and that will greatly shorten your bearing life.

 

[diesel research]

Yes, as others have mentioned, visual inspection of the gasket is the ONLY** method of 100% accuracy. Even then, it doesn't guarantee that is the only leak.

On the plus side, as soon as you remove the cylinder head, it is guaranteed the gasket will be bad and require replacing, even if it wasn't bad before.

***I am not sure, as I have never tried it, but with the advancements in electronics and borescopes, it might be possible to actually see a leak from inside the engine IF the cooling system can be pressurized enough to recreate the leak w/o popping a heater core or anything else.

 

[scott37300]

Do you have coolant in the oil or oil in the coolant? Are there leaks around the head gasket? Does the exhaust put out sweet smoke? Have you done a coolant pressure test? Have you done a compression test?

When I drained the coolant it was brownish and had an oily sheen to it.

No, it could also be a cracked head, or a cracked cylinder block, or it it uses them, a cracked liner. Sadly, there are a number of ways for combustion gases to get into the coolant.

You can run a compression test on each cylinder and hopefully narrow it down to a specific cylinder. You can monitor coolant system pressure with the engine running. This can give you an idea of the severity of the leak.

In the event that the compression test and the appearance of the spark plugs fail to identify which cylinder has the problem then you might want to leave the spark plugs out. Next, with everything at room temperature, make sure that the cooling system is full, and then use a coolant system tester to run the pressure of the cooling system up to it's normal pressure and leave it sit for a while. If it leaks down, pump it back up. If it doesn't leak down, things just got a lot harder.

Next, then tie a small piece of light colored cotton cloth to a thin piece of stiff wire and run it down each spark plug hole and wipe the low part of the cylinder. The wet one will be your leaker.

You have to pull it apart to determine what failed, but at least you know which cylinder to scrutinize.

WoD

Thanks for the detailed advice. I have a compression tester and a coolant pressure tester so will hook them up tomorrow. I assume I'm looking for one cylinder to be low on compression?

 

[greaseyjockey]

Make sure you don't get any coolant up into your combustion gas detector, it will cause an automatic fail. Depending on how the gasket failed, you may get oil in the radiator/ coolant in oil, bubbles/ exhaust smell in radiator, coolant in exhaust. A cooling system pressure test may push coolant into the combustion chamber, a leakdown tester may leak into coolant or into an adjacent cylinder. Could be any combination of these as well.

 

[BillK]

Scott,
Once you have determined that you have combustion gas in your cooling system, which your tester already told you, there is absolutely no way to determine if it is from a head gasket leaking or from a cracked head or block. In my experience, it is about 50-50. I see on an average of 4-5 cylinder heads every single day and probably half of them are cracked and the other half have a leaking head gasket. Only way to tell is to pull the head and take it to your machine shop to have it Magnafluxed or Pressure tested depending on the material it is made from. Dont waste your time buying any other tools, the one you have is what 99% of the good auto repair shops use to diagnose head gasket/cracked head problems.

Also, it is pretty rare to have the actual engine block crack and cause this problem, so I wouldnt worry too much about that.

If you post the year, make and model engine you are working on, I might be able to tell you what we usually see wrong with the heads.

Hope this helps,

 

[Wrenches of Death]

but with the advancements in electronics and borescopes, it might be possible to actually see a leak from inside the engine IF the cooling system can be pressurized enough to recreate the leak w/o popping a heater core or anything else.

I like your concept, VERY clever.

You know, it's probable that it might work without even pressuring the cooling system. If there wasn't a puddle in the low spot, there could still be traces of rust in that hole and there would probably be noticeably less carbon on the piston and/or head and valves.

WoD

 

[Wrenches of Death]

When I drained the coolant it was brownish and had an oily sheen to it.

It's not a 3.1L or 3.4L Buick V6 is it?

Thanks for the detailed advice. I have a compression tester and a coolant pressure tester so will hook them up tomorrow. I assume I'm looking for one cylinder to be low on compression?

Yes, either one low hole, or two adjoining cylinders both low.

WoD

 

[diesel research]

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I suppose one could build their own, but it would be very labor/cost intensive.

 

[Racr350]

Easiest way to make a quick check without any tools is to pull the radiator cap, run the car, and check for constant bubbles. If there are bubbles, time to get the leak down tester out and check each cylinder for 1. A leak shown by the gauge and 2. Bubbles again in the cooling system when the pressurized air is applied. Piece of cake.

 

[bgott]

You don't need a leak-down tester. Pull the schrader valve out of your compression gause adaptor hose and put shop air to it. Who cares if it has twenty percent leakdown, where is the air going?

 

[richfinn]

I have another method to pin point which cylinder might be leaking combustion gas into the coolant jacket.

1. remove spark plugs and disable ignition system.

2. remove drive belt from water pump if possible.

3. fill coolant system to the very top so its on the point of overflowing from the header tank or radiator.

4. Fitting one spark plug at a time (you must only have one plug installed at any one time) crank the motor.

5. The leaking gas bubbles from a faulty cylinder will cause the coolant to overflow when you hit the leaking cylinder.

 

[Sick Puppy]

Only way to tell is to pull the head and take it to your machine shop to have it Magnafluxed or Pressure tested depending on the material it is made from.

lol I remember talking to a mechanic here about magnafluxing, and he had no idea what I was talking about. And I have no mechanical or engineering experience whatsoever...

 

[scott37300]

Scott,
Once you have determined that you have combustion gas in your cooling system, which your tester already told you, there is absolutely no way to determine if it is from a head gasket leaking or from a cracked head or block. In my experience, it is about 50-50. I see on an average of 4-5 cylinder heads every single day and probably half of them are cracked and the other half have a leaking head gasket. Only way to tell is to pull the head and take it to your machine shop to have it Magnafluxed or Pressure tested depending on the material it is made from. Dont waste your time buying any other tools, the one you have is what 99% of the good auto repair shops use to diagnose head gasket/cracked head problems.

Also, it is pretty rare to have the actual engine block crack and cause this problem, so I wouldnt worry too much about that.

If you post the year, make and model engine you are working on, I might be able to tell you what we usually see wrong with the heads.

Hope this helps,

Thanks for all the advice everyone. It's a 2000 3.2L chrysler. I did a pressure test today and it drained down about a pound a minute or so. I also did a compression test and all the cylinders were within about 5-10 PSI, all right around 150-155. Didn't see any sure tell signs on any of the plugs either, not saying there wasn't but it wasn't anything taht really stood out for me to tell.

So, I'm going to place an order with tooltopia tonight for a balancer puller and a few other items. Should I also get a leak down tester to see if I can narrow down which cylinder is the leaky one? Or should I just order the head gasket parts and tear into things? Would a leak down tester help in any way or since I already did the combustion gas test and it failed would the leak down tester be a waste of money? Would it be able to tell me anything more than the combustion tester? If so do I need to know what it will tell me or should I just skip it and order the parts and tear into it and get it fixed?

Thanks again

 

[csargents1546]

Another way to test it is to put a pressure gauge inline on your cooling system, typically a vent hose to the degas bottle, get it up to operating temps, relieve the pressure on the cooling system, drive semi hard, trying to build as much pressure in the cylinders and the combustion gas will make its way to the cooling system, if it does you should get a pressure reading of 14-16 psi depending on the rating on the vent cap.

 

[greaseyjockey]

are you sure you didn't get a little coolant in the test fluid? it will automatically change color if you do. from what i gather that was your only symptom? leakdown is usually pretty noticeable when testing for it, i doubt 1 psi/ minute (i know not an accurate test) would be outside acceptable leakdown on a tester. and if compression is good... unless you really have a hard on for tearing your engine apart, i would make sure that she really has a problem.

 

[scott37300]

are you sure you didn't get a little coolant in the test fluid? it will automatically change color if you do. from what i gather that was your only symptom? leakdown is usually pretty noticeable when testing for it, i doubt 1 psi/ minute (i know not an accurate test) would be outside acceptable leakdown on a tester. and if compression is good... unless you really have a hard on for tearing your engine apart, i would make sure that she really has a problem.

No hard on here, not looking forward to it since parts alone are going to be around 500 plus machine shop.

The original symptom was when I drained the coolant to put new in the old came out brownish in color and had an oily sheen to it. This is what started this whole thing.

 

[treasureseeker]

Oil in coolant will look milky and will be a gluey substance all over the inside of the overflow bottle and radiator cap seal. You can have a head gasket fail with only the oil and coolant mixing and without combustion pressure mixing with the cooling system. A leak down tester will not show a problem in that case.

 

[BillK]

Scott,
Unless the head gasket is totally disintegrated, which I doubt because it is a multi layer steel one, the leak down tester will just be a waste of money. There will be more leakage past the rings than the head gasket so you really will not be able to tell anything.

By the way, the gaskets on those engines are very hard to "read" and tell where they are leaking. Most of the time you just have to go with your gut feeling and replace them.

Make absolutely certain that whichever machine shop you use is capable of putting the correct finish on the heads for the MLS gasket. It has to be perfectly flat and very very smooth, almost mirror finish. It needs to be 15 to 30 Ra.

Hope this helps,

 

[greaseyjockey]

old nasty never changed coolant can look like that also... what i mean to say is don't fix it if its not broke. if your only symptom is nasty coolant and MAYBE a failed combustion gas test, i might try running it with some fresh coolant for a bit and see what happens. make sure you get all the old gunk out first though so you can see how fast it gets nasty again.

 

[oldtools]

Bunch of white smoke coming out of tailpipe?

 

[alvafang]

Look at the oil and examine in order to determine if engine coolant is present. When your head gasket fails it's often between a water jacket and an oil galley hole. A failure in this spot will allow coolant to enter and contaminate the oiling system. If you have coolant in your oil it will often have a creamy appearance to it, almost like chocolate milk. Even if the oil looks good on your dipstick you can drain out a small sample from the oil pan and examine it under light for the presence of water droplets.

 

[Stick]

I'm pretty sure I have a blown head gasket. I have an older combustion block tester, the ones that the blue fluid turns yellow if a blown head gasket. Is the car fails this test and the fluid turns yellow does this mean head gasket 100%?

Nope, the blue fluid is Bromothymol blue (the same thing used to test for the presence of amniotic fluid in the doctor's office), and it simply tests for a change in pH levels. The most common factor in a pH shift with a blown head gasket is the introduction of combustion gasses such as CO2. However contamination of the fluid (like the introduction of coolant into the reaction chamber) is enough to skew the test. As such, it's an indicator of a blown head gasket, but it isn't a definitive guide.

I'd run a compression check and pressure test the cooling system, and go from there.

 

[richfinn]

My method works better than pressure testing the coolant system because your using the compression of the cylinder which is at least 10 times more than you can safely apply with a pressure tester and it rules out the combustion gas getting trapped somewhere and not making it to the reaction fluid or contamination. The best part is you know which cylinder is leaking so when you pull the head you know where to look for the breach. If the gasket shows no signs of a leak I then fill the water jacket up and leave it to sit for a couple of hours and then look to see if block has any cracks. If it doesnt leak (have had two where it did in 25 years) I send the head off for a hot pressure test and skim.

 

[scott37300]

I'd run a compression check and pressure test the cooling system, and go from there.

I did a compression test and all cylinders were 150 to 155. Didn't see any sure signs on the plugs either.

I did a pressure test also and it leaked slowly, about 1 psi every minute or two.

 

[Stick]

I did a compression test and all cylinders were 150 to 155. Didn't see any sure signs on the plugs either.

I did a pressure test also and it leaked slowly, about 1 psi every minute or two.

That's a little more pressure drop than I like to see. I usually look for no more than 1-2psi in five minutes or so.

If you really want, I'd probably throw some coolant dye in the system and check for leaks that way (check the tailpipe for dye). I'd also mark the overflow bottle or reservoir and check it to make sure it isn't burning the coolant.

A little oily residue often isn't a complete cause for concern, it all depends on just how much is there and what it looks like.

 

[scott37300]

That's a little more pressure drop than I like to see. I usually look for no more than 1-2psi in five minutes or so.

If you really want, I'd probably throw some coolant dye in the system and check for leaks that way (check the tailpipe for dye). I'd also mark the overflow bottle or reservoir and check it to make sure it isn't burning the coolant.

A little oily residue often isn't a complete cause for concern, it all depends on just how much is there and what it looks like.

I will do another pressure test and time it a little better this time, didn't really time it last time so was more of a guess. I going to flush the cooling system with some water and see then put some more new coolant in to make sure most of the old **** is out. Then I will add some dye. Should I leave the dye out of the coolant and put some in the oil for now since from what I can tell I'm getting oil into the coolant? Then I could check to see if the dye in the oil gets into the coolant?

I'm also going to order a new uview combustion gas detector. I bought mine used and it's older so I'm just going to get a new one to make sure it's giving accurate results.

 

[fitz11]

Sounds like your looking for an excuse to buy tools. Id flush the coolant and see how fresh stuff turns out then inspect the oil before spending money. Because as of now it sounds like the tests indicate no real problem. Always check the easy things first

 

[scott37300]

Sounds like your looking for an excuse to buy tools. Id flush the coolant and see how fresh stuff turns out then inspect the oil before spending money. Because as of now it sounds like the tests indicate no real problem. Always check the easy things first

I don't mind spending some money on diagnostic tools to try and figure this out. The way I figure it is that alldata says something like 12 hours so I have around 1000 to spend on tools and still be ahead of the game, not that I want to spend any more money than I have to. I try to buy all the tools I need or that will make the job easier in order to make my life easier.

All the bad head gaskets I have done were pretty easy to tell. This one is driving fine, no over heating or hard starting. Compression seems fine. I'll flush the cooling system this week and go from there. I'm still going to order a new combustable gas tester just to be sure. Since it failed that test but I bought that tester used. To me it's worth the 40 bucks to get a new tester and some new fluid to make sure it wasn't my used tester that gave the bad results.

 

[Stick]

I'm also going to order a new uview combustion gas detector. I bought mine used and it's older so I'm just going to get a new one to make sure it's giving accurate results.

Make sure you pick up one that has two reaction chambers in it instead of the type with just one chamber. Helps to keep the false positives down from something like coolant being accidentally sucked into the reaction chamber.

From the sounds of it, other than the possible false positive of the combustion leak detector (always use fresh fluid), it doesn't really sound like a bad head gasket unless you managed to catch it before it has really started to let go. Honestly, I'd probably just flush the coolant and re-test for combustion gasses before rushing into any other troubleshooting or diagnosis. If the re-test came up negative I'd probably talk to the customer, explain what you found and the potential for problems resulting from a bad headgasket, and ask them to come back after 3-500 miles for a quick re-check.

 

[scott37300]

Make sure you pick up one that has two reaction chambers in it instead of the type with just one chamber. Helps to keep the false positives down from something like coolant being accidentally sucked into the reaction chamber.

From the sounds of it, other than the possible false positive of the combustion leak detector (always use fresh fluid), it doesn't really sound like a bad head gasket unless you managed to catch it before it has really started to let go. Honestly, I'd probably just flush the coolant and re-test for combustion gasses before rushing into any other troubleshooting or diagnosis. If the re-test came up negative I'd probably talk to the customer, explain what you found and the potential for problems resulting from a bad headgasket, and ask them to come back after 3-500 miles for a quick re-check.

Thanks Stick. I just ordered the uview tester which is the two chamber one, the one I have now is just a single chamber one. The "customer" is myself, so no need to try and sell anything. I'm going to flush the coolant tomorrow or thursday and then retest when the new tester gets here. I'll keep my fingers crossed that it's not a head gasket but we'll see.

 

[quattrojon]

I have another method to pin point which cylinder might be leaking combustion gas into the coolant jacket.

1. remove spark plugs and disable ignition system.

2. remove drive belt from water pump if possible.

3. fill coolant system to the very top so its on the point of overflowing from the header tank or radiator.

4. Fitting one spark plug at a time (you must only have one plug installed at any one time) crank the motor.

5. The leaking gas bubbles from a faulty cylinder will cause the coolant to overflow when you hit the leaking cylinder.

Excellent info, thanks for sharing.

 

[richfinn]

Excellent info, thanks for sharing.

My pleasure Jon

 

[fitz11]

I don't mind spending some money on diagnostic tools to try and figure this out. The way I figure it is that alldata says something like 12 hours so I have around 1000 to spend on tools and still be ahead of the game, not that I want to spend any more money than I have to. I try to buy all the tools I need or that will make the job easier in order to make my life easier.

All the bad head gaskets I have done were pretty easy to tell. This one is driving fine, no over heating or hard starting. Compression seems fine. I'll flush the cooling system this week and go from there. I'm still going to order a new combustable gas tester just to be sure. Since it failed that test but I bought that tester used. To me it's worth the 40 bucks to get a new tester and some new fluid to make sure it wasn't my used tester that gave the bad results.

Sounds like good logic to me. I would just hate for you to spend that much and overlook something simple.

 

[scott37300]

That's a little more pressure drop than I like to see. I usually look for no more than 1-2psi in five minutes or so.

If you really want, I'd probably throw some coolant dye in the system and check for leaks that way (check the tailpipe for dye). I'd also mark the overflow bottle or reservoir and check it to make sure it isn't burning the coolant.

A little oily residue often isn't a complete cause for concern, it all depends on just how much is there and what it looks like.

After work today I flushed the system 4 times with water. It was still a little brownish each time but looked like it was getting cleaner. I also hooked the stant up again and timed it this time. The other day I used a mityvac universal adaptor like this one, http://www.tooltopia.com/mityvac-mv4506.aspx. I usually just keep it on the stant since it's "universal". But today I just used the stant since it hooks right up to this tank. I timed it for 8 minutes and there was very little to no leaking going on. I think my mityvac universal adapter might not have sealed up good or something.

I ordered a new combustion gas tester and it should be here in a couple days. Got this one from tooltopia, http://www.tooltopia.com/uview-560000.aspx. Will see how that goes when the tester gets here.

Based on the compression test yesterday and the pressure test today I would say the head gasket is good. That would be nice if it isn't a blown head gasket. Guess I'll wait for the combustion gas tester and see what that says.