I worked one shop for 4 days. I had a car with a blow head gasket. Shop foreman wouldn’t accept the diag if the block tester did not read it. He made me bleed the coolant system for 3 days. 4th day he told me to drive it. I drove it about half a mile and came back into the shop rolling smoke. He finally believed me. I quit the next day. Shop wasn’t worth working at anyways. Always research a place before you apply or accept a job
Don't forget the old personal sniffer works too if the failure is severe enough haha. I've pulled some cars into the shop and just one sniff of the coolant been like yup that'sa bad head gasket. Always verified it with another method.
Luckily the shop I'm at now has the gas analysis from snap on. It makes hg leak test very fast and accurate. I used to use my leak down test and pressurize the cylinder than watch for bubble in the cooling system with a no spill funnel.
I have also found headgasket leaks with a cylinder leakage test. 100psi in the cylinder at TDC with both valves closed. You can hear/see bubbles in the cooling system
Good talk. Years ago car came in with little coolant, customer said it overheated. Filled it up, let it idle for an hour, acted fine while I worked on other car. Went for quick angry drive, suddenly smelled coolant and it’s pumping in overflow. Ease it into shop, check it with classic color change tube on radiator with no change. Check tester at exhaust, changes fine. 2x angry drive pumps coolant out hard. Check spark plugs and see nothing. Pressure test rad. nothing. Nerve racking hours later with top of v6 stripped off -find Rear engine head, head bolts pulled out of block. If snap on had a 5 gas on truck that day, I would have bought it.
Thank you for calling bullshit on block testers. Many service advisors and mangers need to hear that. RC test and invert the image with the pico and maxiscope is nice because you can see the gap and also look at mode six data for misfires. The pulse sensor works great.
An old German mechanic taught me the coke bottle trick, fill bottle with water put line of vent drive it hard jump out go check it , if it has bubbles BOOM she done , modern cars you might hv to fab up some adapter. But I like that pulse sensor test also
The very best way that makes me feel comfortable in being 100% certain its a headgasket leak is doing a test with cylinder leakage. Bring cylinder up to tdc compression stroke. Hook up cylinder leakage tester. Shoot in 80-100psi. If headgasket leak in that cylinder. Air bubbles will come into coolant reservoir.
what about getting the engine hot, pulling a spark plug and putting an inspection mirror over the hole and see if condensation forms on the mirror, and inspect it ?
I figured the 5 gas analyzer would work. But I put the probe in a new jug of antifreeze and it was reading hydrocarbons there. So I'm not sure it works.
They work... more invasive, have to set-up in spark plug hole (glow plug or injector for diesel), set engine to tdc for each cylinder, it takes some time, more time than using a bore scope. Where they are good os determining which cylinder is leaking as you can pressurise that cylinder and watch for bubbles entering the cooling system
@@CPthetooladdict It pressurizes the the cylinder and then you pull radiator cap off and look for air coming through the radiator. You can put your hand over the the cap opening and feel it build pressure and you can even put your cooling system pressure tester on the radiator assuming there are no other coolant leaks and watch the pressure gauge build up.
I have a Hemi Charger in the garage right now with a whole bunch of oil in the coolant. No coolant in the oil. I had it apart about a month ago for cam/lifters. Before pulling it apart that time, there was a small amount of oil in the coolant. Pulled it apart and did the cam and lifters. I had the heads checked for cracks/flat at the machine shop and they tested ok. I pressure tested the oil cooler and it seemed ok as well. Now have about 2 qts of oil in the coolant. I am replacing the oil cooler and see if that does it. Otherwise off with the heads and checking for a cracked block. 🙃
@@asmautollc Yeah: Chrysler or whatever company they want to be called can't seem to get the lifter/cam thing correct. 🤨 I don't mind wrenching on their stuff though, pretty straightforward.
Just to make sure I understood you correctly: If the Combustion Leak Detector detects combustion gas you definitely have a head gasket leak but you may have a leak even if there is no combustion gas leak. Is that correct?
No mention of running the car up on the funnel? The ones we've got have a clear window and one-way valve to stop air entering sytem. Just get to operating temperature and watch for bubbles through the window. Bubbles only get there via combustion gasses in cooling system e.g. head leak or EGR cooler leak. In some cases cavitation from waterpump can do it but this is pretty rare.
I worked one shop for 4 days. I had a car with a blow head gasket. Shop foreman wouldn’t accept the diag if the block tester did not read it. He made me bleed the coolant system for 3 days. 4th day he told me to drive it. I drove it about half a mile and came back into the shop rolling smoke. He finally believed me. I quit the next day. Shop wasn’t worth working at anyways. Always research a place before you apply or accept a job
I Luv when the borescope shows evidence.. solid find !!
Don't forget the old personal sniffer works too if the failure is severe enough haha. I've pulled some cars into the shop and just one sniff of the coolant been like yup that'sa bad head gasket. Always verified it with another method.
Luckily the shop I'm at now has the gas analysis from snap on. It makes hg leak test very fast and accurate. I used to use my leak down test and pressurize the cylinder than watch for bubble in the cooling system with a no spill funnel.
Thanks! that's a great tip about using the spill free funnel!
I have also found headgasket leaks with a cylinder leakage test. 100psi in the cylinder at TDC with both valves closed. You can hear/see bubbles in the cooling system
Yep, that’s what I do too
Good talk. Years ago car came in with little coolant, customer said it overheated. Filled it up, let it idle for an hour, acted fine while I worked on other car. Went for quick angry drive, suddenly smelled coolant and it’s pumping in overflow. Ease it into shop, check it with classic color change tube on radiator with no change. Check tester at exhaust, changes fine. 2x angry drive pumps coolant out hard. Check spark plugs and see nothing. Pressure test rad. nothing. Nerve racking hours later with top of v6 stripped off -find Rear engine head, head bolts pulled out of block. If snap on had a 5 gas on truck that day, I would have bought it.
Thank you for calling bullshit on block testers. Many service advisors and mangers need to hear that. RC test and invert the image with the pico and maxiscope is nice because you can see the gap and also look at mode six data for misfires. The pulse sensor works great.
An old German mechanic taught me the coke bottle trick, fill bottle with water put line of vent drive it hard jump out go check it , if it has bubbles BOOM she done , modern cars you might hv to fab up some adapter. But I like that pulse sensor test also
The very best way that makes me feel comfortable in being 100% certain its a headgasket leak is doing a test with cylinder leakage. Bring cylinder up to tdc compression stroke. Hook up cylinder leakage tester. Shoot in 80-100psi. If headgasket leak in that cylinder. Air bubbles will come into coolant reservoir.
what about getting the engine hot, pulling a spark plug and putting an inspection mirror over the hole and see if condensation forms on the mirror, and inspect it ?
Here in California most people use a Gas Analyzer. Since we have emissions testing , I haven't tried the pulse sensor yet.
A 5 gas is hands down the best method. Takes well under a minute to easily find hydrocarbons in the coolant .
Last month I had one come in pouring coolant out the muffler.
Good stuff, spoken from experience. Thanks
I figured the 5 gas analyzer would work. But I put the probe in a new jug of antifreeze and it was reading hydrocarbons there. So I'm not sure it works.
To add to the pressure test method, when you take the plugs out go ahead and check those also for one or some of them being cleaner.
I love the tip. i'm gonna go cut a hole in my spill free asap. ty
Yeah I've had the leak detector give me false readings a few times.....especially when the leak is on the exhaust part of the gasket
Thank you for this video! Helpful!
What about a leak down tester?
How's a leak-down tester going to work to pressurize the coolant system?
They work... more invasive, have to set-up in spark plug hole (glow plug or injector for diesel), set engine to tdc for each cylinder, it takes some time, more time than using a bore scope.
Where they are good os determining which cylinder is leaking as you can pressurise that cylinder and watch for bubbles entering the cooling system
@@CPthetooladdict It pressurizes the the cylinder and then you pull radiator cap off and look for air coming through the radiator. You can put your hand over the the cap opening and feel it build pressure and you can even put your cooling system pressure tester on the radiator assuming there are no other coolant leaks and watch the pressure gauge build up.
Thanks for the idea of the hole in the top, but I also agree what about a leak down tester ?
Leakdown includes pressure loss from valves and rings so not a great test
True true it’s not specific head gasket tester fair enough. But it’s definitely a go to with mechanical caused misfiring
When you are using the pulse sensor. Are you testing with the car running or just cranking the engine?
Good stuff. Another good tool an old BAR 90 Smog Machine. Doesnt the block tester not react to Co?
Very helpful, great advice
I have a Hemi Charger in the garage right now with a whole bunch of oil in the coolant. No coolant in the oil. I had it apart about a month ago for cam/lifters. Before pulling it apart that time, there was a small amount of oil in the coolant. Pulled it apart and did the cam and lifters. I had the heads checked for cracks/flat at the machine shop and they tested ok. I pressure tested the oil cooler and it seemed ok as well. Now have about 2 qts of oil in the coolant. I am replacing the oil cooler and see if that does it. Otherwise off with the heads and checking for a cracked block. 🙃
We typically see that with Pentastar engines along with or followed by the “Pentastar tick”.
@@asmautollc Yeah: Chrysler or whatever company they want to be called can't seem to get the lifter/cam thing correct. 🤨 I don't mind wrenching on their stuff though, pretty straightforward.
Great tips!
Great video
Just to make sure I understood you correctly: If the Combustion Leak Detector detects combustion gas you definitely have a head gasket leak but you may have a leak even if there is no combustion gas leak. Is that correct?
Correct
you didn't mention leak down test...?
No mention of running the car up on the funnel? The ones we've got have a clear window and one-way valve to stop air entering sytem. Just get to operating temperature and watch for bubbles through the window. Bubbles only get there via combustion gasses in cooling system e.g. head leak or EGR cooler leak. In some cases cavitation from waterpump can do it but this is pretty rare.
Find it sus you didn’t mention a leak down test maybe change your name to flat rate mechanic