Freeze plug?

 

Could be, but that wouldn't get exhaust gas in the coolant.

I am beginning to wonder if I simply screwed up the exhaust gas test and got coolant into it. Even after multiple flushes, it's still pretty rusty, and that would have made the blue test liquid look yellow.

I'm working from home this week and two of my boys are doing the wrenching for me, and I run out every now and then to see what's going on. My oldest one has inspected the cylinder walls and saw no problem, but I plan to inspect them myself in between meetings today.

He's going to pull the water pump this morning, too. That should be interesting.

While I've got the head off, assuming I do not find a cracked block, I'll replace the lifters, too. For $7.44 each from NAPA I think I'd be crazy not to.

 

Must be NICE to have a pit crew. LOL

 

Yes, it is very nice. They are enjoying learning, and I'm paying them for the work. Not exactly shop rates, but they like it.

Well, the water pump tells the story. It's shot. I'll be picking up a new one. NAPA has everything I need in stock, including the Fel-Pro gasket set (all of the gaskets that touch the head) and even the inlet pipe. Lifters, too.

Next question: Please take a look at these shots of the back of cylinder #6. The rest of the cylinders look great. No scoring, no strange markings. The original crosshatching is even visible. But #6.... The front and back have some odd markings. I have some ideas about the cause, but I want to get your feedback before I say anything. First pic is the FRONT wall of cylinder 6, the other two are of the rear wall.

 

ever heard of cracked intake manifold? 99 xj. engine pulled and taken to shop for rebuild because coolant in oil. My headgasket was newer and correctly installed according to machine shop when they tore it down. head (0630) fluxed and no cracks found. gasket was good. heres the intake mani they cleaned and found a crack. they called a "jeep guy" they knew who did lots of jeep work and he said he had seen this intake crack before. ill try an post pic. they mentioned moisture getting in thru the CcV system

 

Travis, welcome to the forum. It is considered rude to hijack a thread (like you did). Please create your own thread which will net you much more help.

Blueridge, those marks are only on the front and rear part of the bore?

Edit: Apologies to Travis I read the post a little too fast and jumped to conclusions lol.

 

sorry if it seems like a hijack. I was posting these pics as a reference for something to check out as hes having similar issues to what i had. Disappearing coolant issues. I did start a new thread for my intake question as well though.

 

I got ya, Travis. Thanks for that. I'm not seeing how that could account for exhaust gasses in the coolant, though.

Jeepin', re-read his post. No hijack here.

Yes, those marks are on the front and rear of the bore. The sides get more wear, so I'm thinking that they might have been all around but got worn down.

 

My apologies, I jumped the gun there. We get a lot of newbs that do hijack threads around here lol.

I've seen scored cylinders before but not with that kind of pattern. I'd love to know if anyone has an idea of what could cause that.

 

By the way, here's my shopping list for NAPA.

What I need:

1. Water Pump
2. Water Pump Inlet Tube
3. Head Gasket set (Fel-Pro,complete with all gaskets that touch the head)
4. Cylinder Head Bolt set (Fel-Pro)

While I'm in there:

1. Power Steering Pump
2. Lifters (12)

Am I missing anything?

 

I've been guilty of "ready, fire, aim" myself a time or two.



Me, too. I have an idea, but I'd love to hear from others, first.

 

Checked. They look fine. No trace of a leak.

 

it looks like rust and that piston looks exceptionally clean.

 

That would be where the head gasket was leaking, eh?

 

Yes, I'm thinking the leak was into that cylinder (that's the one that's 5 pounds less on compression), and of course it was going on for a while. A small leak, and when coolant (pretty much rusty water) was left in the cylinder after shutting down the engine, some settled down into the oil rings, and created that pattern of dots at whatever level the piston happened to stop. Do that a few times, and you get that pattern.

See the ring pattern?






What's bugging me is the fact that I saw no sign of any erosion on the head gasket. There's no obvious failure point. I would expect to see some scoring or cutting or something on the head gasket and a matching pattern on either the head or the block side (or both).


Why the rusty water? I started an Amway flush in the summer, but life has been crazy busy with work and urgent projects at home (rescuing my septic system) and a new baby (complete with wife almost not making it), and a major project with my family van, and I didn't get around to the drain and fill with coolant part of the deal.

So, at this point I'm wondering if I got enough ice in the water passages to have broken something. The morning I had the overheat problem, it was pretty cold. It had been about 15F overnight.

But I can't see anything. No visible cracks. Might be too small and only opens up with heat?


At this point I'm thinking I'll put some Marvel Mystery Oil in the cylinders, throw it back together, and see what I get.

What do you folks think?