Oh Crap! I think I just killed it.

[Sluggo]

What about my other questions?

WHADDABOUT 'EM? HEH? My answers not GOOD ENOUGH FOR YA? HAH?
Colin :blackknight:

Didn't see your post.

[Amskeptic]

Didn't see your post.

Used 1.8 heads with a failed valve seat at 800 miles, no overheat on your watch, right?
Do you have any recourse with seller? Did a machine shop go in there to give you a valve job? Oy. . . . we need to come up with a good seat inspection procedure, or a swaging method that can help lock them in.
Colin

[Sluggo]

1. Is that a lot of carbon for 800 miles?
2. Should there be oil in there?
3. Is that piston shot? The dent is about 1/8".
4. Can I seal the head to the piston with Permatex to stop the leak?
5. Anything else I should check for?

1) Not necessarily for an engine that has mostly puttered around on surface streets. Some is caused by oil coming up past the rings.

Good to know. Just surprised me because it was all bright & shiny a few months ago.

2) Not to that degree. How were the cylinders honed and what kind of rings?

I defer to Bottomend on that. He did the work. I know it had a nice cross hatch. Rheinholdt (sp?) rings

3) No, it can be smoothed out. Check the ring lands very carefully if you pull the cylinder. You want absolutely consistent gap across the land and the top of the ring. If it gets tight at the scene of the damage, then the piston has collapsed a land, replacement is then called for.

Good! With Christmas a few weeks away and it being my Colin's first I don't need to spend $ on a piston & cylinder set. I'll check the ring lands tomorrow.

4. No. The leak is a symptom. Sealing would be a mask. Sealing is also not allowed. You may lap the cylinder barrel to the head. Does the fin boss hit the head before the very top of the cylinder contacts the head sealing surface? I had a head flycut too deep and the cylinder fin area was contacting the outside of the head. I got 100,000 miles out of it, but the heat was always stinky due to leaking when the engine was cold.

Heads were flycut by our machinist and Bottomend & I both checked em' out. Perfect fit.

How the hell do you pull a head with the engine still in? You can't get the top nuts?

[Sluggo]

Used 1.8 heads with a failed valve seat at 800 miles, no overheat on your watch, right?
Do you have any recourse with seller? Did a machine shop go in there to give you a valve job? Oy. . . . we need to come up with a good seat inspection procedure, or a swaging method that can help lock them in.
Colin

The highest temp I got was on the freeway last weekend going to Hawthorne. VDO Gauge read 375. Backed off a little and the temp went right down. Oil never got over 210.

Seller is a jerk who called me "trailer trash" and "working class scum". Then went on to brag about his airplanes & money. Nice Guy.

Machinist is a friend who has been a VW (and everything else) machinist for decades. I think you've met him. I'll go in on Monday. I'm sure he'll make everything right.

So the oil in the combustion chamber would be from improperly broken in rings? I did question how good of a job I was doing. And that is the cylinder that had the low compression reading.

[Amskeptic]

Does the fin boss hit the head before the very top of the cylinder contacts the head sealing surface?

I had a head flycut too deep.

Heads were flycut by our machinist and Bottomend & I both checked em' out. Perfect fit.
How the hell do you pull a head with the engine still in? You can't get the top nuts?

This ain't about "perfect fit." It is about too deep a hole in the head. It is a common and stupid machining error that can only be cured by using sealing rings between the head and the cylinder. Check it out. I am talking about the fin "boss" of the cast iron cylinder hitting the surface of the head that is surrounding the cylinder holes you had flycut. You need to see a gap between the cylinder fins and the head surface.

You can remove the upper cylinder covers in situe.
Colin

[chitwnvw]

You may lap the cylinder barrel to the head.

That's what I did. Since you know you have a problem use machinist dye, to get a better idea of your seating and high and low spots...

[Sluggo]

This ain't about "perfect fit." It is about too deep a hole in the head. It is a common and stupid machining error that can only be cured by using sealing rings between the head and the cylinder. Check it out. I am talking about the fin "boss" of the cast iron cylinder hitting the surface of the head that is surrounding the cylinder holes you had flycut. You need to see a gap between the cylinder fins and the head surface.

I'll check it out. I have some sealing rings that we didn't use.

[chitwnvw]

I think that avatar's a keeper, Sluggo.

Edit: I miss Cap'n Chronic...

[Sluggo]

Just got back from my machinist. He said that it was not one of the seats he replaced. It's an original seat. But since he inspected and approved it he's gonna take care of me. Valve and guide are okay but he's gonna replace them anyway. Just to make sure. And he's gonna replace the original seat on the other intake also. Luckily I shut it down right after it happened so he said the damage is minimal. Should have it back tomorrow or the next day.

While the engine was out I took the opportunity to do a few other things.

[Sluggo]

This ain't about "perfect fit." It is about too deep a hole in the head. It is a common and stupid machining error that can only be cured by using sealing rings between the head and the cylinder. Check it out. I am talking about the fin "boss" of the cast iron cylinder hitting the surface of the head that is surrounding the cylinder holes you had flycut. You need to see a gap between the cylinder fins and the head surface.

I checked the 1/2 side and there is the slightest gap. I'll check the 3/4 side when I get the head back.

[Amskeptic]

I checked the 1/2 side and there is the slightest gap.
I'll check the 3/4 side when I get the head back.

Excellent. You know, the slightest gap makes all the difference.
Colin

[bottomend]

There will be a gap on the 3/4 side too. I remember seeing it personally.

I feel really bad about this engine. The couple of times I rod in the bus, I was actually JEALOUS! Even before the carb issue had been sorted out it was a smooth engine. Mine is like a rattly lawn mower compared to Randy's.

I felt the hone job on the cylinders was a good one. Granted, I've only done a few sets of cylinders in my life up to this point but I'm pretty anal about things. There was a consistant 60* x 40* cross hatch imbedded pretty deeply in the walls.

Not trying to pass blame, but I dont think the hone job is the problem with the oil leakage. I think the break-in was probably not as " sprited" (I'm sounding like Colin now....) as it should've been. I know it's hard to ' lay on it" when its a brand new engine but thats whats required to get the "hard" rings to seal againts the "soft" cylinders, otherwise it'll smoke,drip ect.

Randy is either insane or he's found his calling in life.....

[Sluggo]

There will be a gap on the 3/4 side too. I remember seeing it personally.

I feel really bad about this engine. The couple of times I rod in the bus, I was actually JEALOUS! Even before the carb issue had been sorted out it was a smooth engine. Mine is like a rattly lawn mower compared to Randy's.

I felt the hone job on the cylinders was a good one. Granted, I've only done a few sets of cylinders in my life up to this point but I'm pretty anal about things. There was a consistant 60* x 40* cross hatch imbedded pretty deeply in the walls.

Not trying to pass blame, but I dont think the hone job is the problem with the oil leakage. I think the break-in was probably not as " sprited" (I'm sounding like Colin now....) as it should've been. I know it's hard to ' lay on it" when its a brand new engine but thats whats required to get the "hard" rings to seal againts the "soft" cylinders, otherwise it'll smoke,drip ect.

Randy is either insane or he's found his calling in life.....

I got the engine back in yesterday. I'll install the carbs and start her up today.

There is a gap on the 3/4 side.

I agree that it was probably the ring break in. I've had a feeling that I didn't do it just right since I did it. New P&C's are coming in a few months so I'll get a chance to do it again.

I don't know if I've found my calling. But I really enjoy myself and find it very relaxing.

The machinist got a little nervous with the head stories I was telling him. He replaced all the seats, guides & the offending valve (with an original).

[bottomend]

Eyes crossed... good luck.

[hambone]

"Seller is a jerk who called me "trailer trash" and "working class scum". Then went on to brag about his airplanes & money. Nice Guy. "

Why would you give someone like that your $$$$? Doesn't seem like you.