I recently took the car to the dealership after it overheated on me and pushed coolant out of the overflow tank. Dealership used a block tester and diagnosed the car as having a blown head gasket. I had the car towed to a performance shop were a compression and leak down test were performed and found to be normal. The shop ended up finding that the plug for the cooling fans was melted. They ended up ordering a new plug and fans. The IC pump was also found to be intermittently working on inspection they found 1 of the wires was singed so it was replaced and the wiring was bypassed. These repairs fixed my overheating problem and the car is running good. After posting a negative review about my experience with dealership I was contacted by the Service manager who asked me to come in and allow another block test to be performed with me present, I agreed and the test was done this morning. The test fluid turned slightly green/dark green. I'm scheduled to put the car on the dyno again next week should I be concerned about the head gasket based on the findings of block test with no other symptoms?
Block Tester how accurate are they?
- Thread starter 07 Black Beauty
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If there are combustion gases present in the coolant system, the chemical will indicate as such. Since the coolant system is a closed system and combustion gases are indicated, they're getting in somehow, and usually through a head gasket.
With that said, I would also request each cylinder be leaked down. I've had experiences where I had a slight compromise of a gasket and the car would run fine, compression tests did not show low readings on any cylinder, but a leakdown and block test showed otherwise. My 2¢
With that said, I would also request each cylinder be leaked down. I've had experiences where I had a slight compromise of a gasket and the car would run fine, compression tests did not show low readings on any cylinder, but a leakdown and block test showed otherwise. My 2¢
I'll have to check with the shop again, I believe they told me they leaked down the motor. My main concern is possibly doing damage to the motor when it gets put on the dyno to complete my remote session with Lund.
On the plus side if the motor is coming out for gaskets it gives me a reason to do some cams @ the same time
I know, I would love to build my motor the right way, but my wallet and wife wouldn't like it. Hopefully it's just a gasket replacement but nothing is ever that simple
When I blew my head gasket it was between cylinders and there was some flame cutting of the head surface and I presume the block deck surface too. In order to deck the block, it would have required a complete disassembly of the short block. I figured if I went that far, I'd just get a new 5.8 aluminum block and fill it premium parts. If you had decent compression, chances are you're not getting any flame cutting and may just get by with a gasket. However, I'm not sure the engine won't have to come out to do that. Then you have to hope the block or the head surfaces aren't warped from overheating.
Dump all the coolant and refill. Retest after a week or so to see if it comes up again.
Before you drop 15-25K on a new motor worth a try.
Before you drop 15-25K on a new motor worth a try.
I'll definitely be doing more testing before I pull anything apart. The shop I'm using previously mentioned using a boroscope to check the heads, maybe I'll have them do that prior to putting it on the dyno
A borescope will only be able to deternine major engine damage. You going to need to do a leak down or compression test. Pull the dipstick and see if it looks like a chocolate milkshake. If you're getting combustion gasses in the coolant, you may be getting coolant in the crankcase.
Just had the oil changed @ the dealership and they didn't mention any abnormalities, I'll check the dipstick tonight after I give her a bath. Plugs would be stained also?
Let's just say dealerships don't have their best and brightest doing oil changes, so I wouldn't take any comfort in them not telling me about abnormalities. Plugs wouldn't show up anything either. From what I've read of the block test, the chemical is supposed to turn yellow. If it turned green, I'm guessing you don't have a really bad gasket issue, at least not yet. But if something did get warped from overheating, the gasket may be leaking some amount of combustion gasses, but a leak down test would be on my diagnostic list.
Listen to Catmonkey, he knows what he's talking about. Same thing happened on my Grand National, those block tests work. If you're getting milk shake in the oil, you know the problem. It was head gasket in my case (and excuse to put a Stage II motor in there 
). He's also spot on with the dealerships, last fall when I had them change my oil prior to winter storage, the girl that changed it couldn't drive a clutch (stalled it several times making me literally cringe) and I know didn't bother to look at the oil, just let it drain into the waste container. Unless it's someone you know/have a good relationship with, even at the Ford dealer, you're just another car/job to them. Good luck, keep us posted.
). He's also spot on with the dealerships, last fall when I had them change my oil prior to winter storage, the girl that changed it couldn't drive a clutch (stalled it several times making me literally cringe) and I know didn't bother to look at the oil, just let it drain into the waste container. Unless it's someone you know/have a good relationship with, even at the Ford dealer, you're just another car/job to them. Good luck, keep us posted.I'm scheduled to put on her on the dyno tomorrow to complete the remainder of my remote session with Lund Racing. I think I'll have the shop do some more diagnostic testing prior to running her hard on the dyno. Data logging wise is there something that can be monitored as a possible indicator of head gasket problem?
Do a leak down and confession test. End of story. Stop looking for other answers, this is what people told you to do and is what needs done.
Both a leak down and compression test were done, shop that performed them said the motor was healthy. Dealership performed the block test and said head gasket was leaking. These conflicting tests are why I'm looking for as many diagnostic tools as possible before I drop the motor out and pull it apart.
Leak down and compression = good
Oil= clean
So we finished the remote tune session, car made 757 RWHP on the dyno today! Only issue seen on the logs is that I'm maxing my fuel system out, so BAP and injectors are in my future
Oil= clean
So we finished the remote tune session, car made 757 RWHP on the dyno today! Only issue seen on the logs is that I'm maxing my fuel system out, so BAP and injectors are in my future
Good deal. If you're still concerned at all, go purchase/rent your own block tester and do another test. But a leakdown test if done properly should show all you need to see for the health of the motor.
http://www.autozone.com/loan-a-tools/block-tester
http://www.autozone.com/loan-a-tools/block-tester
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