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The primary idea here is to show you guys how the top of the line Snap-On borescope/inspection camera is. You might say it’s a tool talk topic, but a non-technician is very unlikely to buy this thing. The other reason I post this here is that you guys would probably find it funny that the service guys presold this job as needing a turbo and I was actually asked to start preparing the used turbo that the customer had already sent to us, before any tech had looked at this car. I was told “they” looked at it out in the parking lot and the intake/boost pipes had oil in it so the turbo seal was bad. So I said how about I look at this thing and actually diagnose it? I got it in, found all boost pipes and the throttle clean/dry, pulled the plugs and found #4 covered in oil, checked compression 150psi on all 4, and produced the following video. (The video is edited with the knowledge the customer will watch it)
After rendering my initial diagnosis of a probable ring/cylinder or headgasket issue because of no evidence that the oil was coming in thru the head, they’re like “oh man, what do we tell this guy we already got him to buy a turbo for it?”. So I tell them “good news it still needs a turbo anyway because of all the soot and debris that’s been blown thru the turbine housing”. I get some questions like “can we not do anything with the head and just put it back the way it is?” and “can you just re-ring the one cylinder?”. My response was “this is a 2L engine that makes 300hp stock and is tuned to produce more. This conversation needs to head in a different direction immediately. I could get this thing apart and find a damaged piston, you know”.
Miraculously, my advice was heeded and I’m to start tearing this engine down in a couple hours and find the point of failure BEFORE we make a parts list. What a concept!
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Dude this is awesome info and I really appreciate the upload. I have yet to start doing engine diag at work I am mainly working on electrical atm. I love how the one guy didn’t know what you meant by piston jets. Then again I guess a lot of engines don’t have them. I am sure you already know this but, whatever you do don’t crank over an diesel engine like that with the camera in it.
That scope also works great on a woman too, if you’re into that kind of thing.
So I figured I’d document this one and show you guys where this whole thing goes. For the 15 min is costing me so far, it’s worth it for the fun of it.
This is the morning’s work.
Great tool. I wish i had one on so mant vehicles ive had to diagnose.
If an engines got a blown headgasket into a cylinder can you see it with the camera?
BAM! home run on this diag!
So I finished tearing this down before I left and found a definitive failure right where I said it would be. See the rest of the teardown pics and it will stick out like a sore thumb. Now I have to find out how I’m going to end up fixing it. It will either be a new piston, all new rings and rod bearing, and hand ball-honing the cylinders or a vastly more expensive short block. The head is being cleaned up by a machine shop and getting new valve stem seals either way. One pic shows a bunch of silicone gasket in the oil pump pickup that came right out, but there’s no outright lubrication damage.
MDK22, the guy who didn’t know about the piston squirters is our very exceptional parts guy, he’s just younger and hasn’t seen everything yet. I took a picture of that and showed that guy the jets, spreading a little knowledge.
[quote=”sinfull” post=120603]If an engines got a blown headgasket into a cylinder can you see it with the camera?[/quote]
If the gasket is fibrous, it’s pretty obvious. If it a multi-layered steel gasket like the video above shows, it can be tough to see because the metal doesn’t really blow out like fiber will. I made a video of a blown headgasket with my last one of those scopes, but I can’t find it now, I may not have saved it. If I can find it, I’ll post it up to show you.
This darker patch of scuffing is right where the cracked part is at TDC and can just barely be felt as a slight depression, and none of the scoring can be felt.
Here’s a pic of that piston crown squirter:
The picture of the underside of the cylinders is that the oil screen pickup that looks like its full of metal? I also saw the cracked piston right under the ring. Also the pic of the tops of the pistons the brown color is apparent on cylinder one but, is there a little on cylinder 4? Also is that brown stuff burnt oil, a burnt spot from improper injector spray, rust, or just debri from taking the engine apart. Like i said I have yet to really get into engine diag at work. I learned the concepts in school and understand how to diag it but, not what things will look like with certain issues.
That would be cool if you did find the video of the fiberous head gasket.
I have always enjoyed this side of the automotive business. Makes me want to get back into it.
[quote=”MDK22″ post=120638]The picture of the underside of the cylinders is that the oil screen pickup that looks like its full of metal? I also saw the cracked piston right under the ring. Also the pic of the tops of the pistons the brown color is apparent on cylinder one but, is there a little on cylinder 4? Also is that brown stuff burnt oil, a burnt spot from improper injector spray, rust, or just debri from taking the engine apart. Like i said I have yet to really get into engine diag at work. I learned the concepts in school and understand how to diag it but, not what things will look like with certain issues.[/quote]
The oil pickup is congested with hardened silicone gasket material, presumably from using too much to seal the oil pan. It had been off and resealed. When it comes to liquid gasket, only use grey, less is more, and prep the surfaces perfectly.
That brown I think is just a camera/lighting anomaly. I don’t remember it being there when I took the head off. I know it wasn’t there when I was wiping off and inspecting all the pistons and rings. As a bit of a bonus, all the residue on the piston faces and the “ridges” at the tops of the cylinders wiped right off because the car has not only been getting a little oil in all the other cylinders too, but also due to this (and all evos) engine being driven hard a lot, gerating lots of heat.
You get a motor apart that has been driven by a normal driver who is afraid to open the throttle or see a tach go over 3,000 rpm, everything a thick, hard, dry, crusty layer of carbon buildup that has to be physically scraped off before using chemicals and rags to dissolve what’s left behind. A couple times, the carbon crust is so hard I have to use a torch to burn it into ash to make it soft enough to remove.
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