Cracked E12 Head? Swap to my spare 121...?

[Summit321 123]

On 11/9/2022 at 5:42 PM, TobyB said:

If you didn't notice binding when the cam came out, you're probably OK.

They have to be noticeably stiff to cause problems, and you'd have remembered that.

 

Total cut of 0.022" isn't too bad- that puts you just a little over the 'limit' of 0.50mm, and that's not

a hard limit.  Add 0.30mm back with the 1.80mm head gasket, and you'll be sportingly fine.

 

The danger with the rings is that you'll measure the ring lands, find that they're a bit too worn,

then you'll be into pistons, and at that point a block bore, and hoo boy!  fresh engine time!

I freely admit that when I have a 'clean it up and run it' engine, I refuse to measure the ring lands

because I just don't want to know.  Then, when it breaks a piston crown, munches a ring, and trashes

the head, I can just shake my head and say 'jeeze, I guess I know how THAT mess could have been avoided.'

Whereas, if you JUST do the top end, the worn rings will burn TONS of oil before anything goes bad,

and you'll probably build something to replace it before it grenades.

 

see how this goes???

 

heh

 

t

 

Heres the rub, no pun intended. 

I continued with dissasembly into the bottom end for a few reasons. One of the primary reasons being peace of mind. I respect that you are able to say oh well I could've avoided that but peace of mind was important to me. I'd rather put in the time now that have bigger issues later and undo all of my work. 

 

Next was the advice I recieved from the technician at the machine shop. He was not convinced that my only problem was in the top end. I trust his expertise, I have gone to him before and had good work, professional, wasn't getting any more cash out of me for it. He warned that if even one ring was sticking then I would never get good compression. I had a damn good opportunity to make sure it was all good down there and he told me to go for it.

 

What I was able to see from above. Three glossy polished cylinder walls and one with some scoring. I felt like it was important enough to hone those barrels and that it would make it worth while to have that increaced assurance for long term engine health. Also for me was the warped head. Clearly a sign of overheating with potential damage to rings.

 

Considering my experience I would not advise everyone removing their head for whatever reason to remove their pistons just because they can. I would recomend that they think long and hard if it would make sence for them considering their particular situation. Dissasembly and trouble shooting go hand and hand and you may come to regret it for coping out and not finding the root problem. In my line of work I see people avoiding that critical step because they dont want to deal with what they know they will find. 

 

Two rings welded in. Cyl 1 C2 and oil control. I got the oil ring off by snapping it piece by piece. The ends are butted up on C2 on that piston and I haven't managed to remove it yet. 69015561926__E0B8F113-5AF5-4F4D-BFB1-E26C96504E32.HEIC69015409828__EF25203F-EBFB-4ED4-8F9C-33EAC5BA5823.HEIC

[Lorin]

Definitely made the right call in removing the pistons. 
 

That entire engine needs thorough inspection. 

[Mark92131]

Here's your photos, just use heictojpg.com to convert them before you attach them to your post.

 

Mark92131

 

 

[John76]

Summit 321 123,

Did you measure the ring lands? 

Just curious to know if they are still in spec despite the frozen/broken rings.

Thanks,

John

[Son of Marty]

Looks like the engine builder missed the ring gap setting.

[jimk]

Maybe it's been said, but the piston looks like it hasn't many miles on it, no deposits even above the top ring.

[TobyB]

No, but that scuffing's not right.  I've pulled 150k pistons that had better skirts...

 

t

 

[jimk]

46 minutes ago, TobyB said:

No, but that scuffing's not right.  I've pulled 150k pistons that had better skirts...

 

t

 

Not sayin it's worth a sh*t, just that it didn't look like it was in service very long.  Overheating and things swell up.  Skirt scoring after that is not suprising.

[Lorin]

2 hours ago, jimk said:

Overheating and things swell up.  Skirt scoring after that is not suprising.

We’re still talking about engines, right ?

[TobyB]

I got a lot hotter than that and didn't score nearly that well...

 

hee

 

Oh, right, pistons.  For cars.

 

t

[ray_]

3 hours ago, TobyB said:

I got a lot hotter than that and didn't score nearly that well...

 

hee

 

Oh, right, pistons.  For cars.

 

t

Toby,

 

What have you NOT broken?

 

[TobyB]

The sound barrier?

 

t

regrets not buying one Concorde ticket, back in the 90's.

[Lorin]

24 minutes ago, TobyB said:

The sound barrier?

 

t

regrets not buying one Concorde ticket, back in the 90's.

 

When I was around 6 to 8 years old we lived in a house in northern Virginia that was directly underneath the flight path of the Concorde leaving Dulles airport. It was pretty awesome hearing that ripping over our house. We used to run outside to see it all the time. 
 

 

 

 

..

Edited November 18, 2022 by Lorin

[Summit321 123]

On 11/15/2022 at 10:21 PM, Son of Marty said:

Looks like the engine builder missed the ring gap setting.

Thats what my engine builder said. They must've beat that ring on because it isn't going anywhere. That piston is scrap. I'm dropping my engine off for him to assess if the scoring and pitting that piston caused is servicable or it needs to be bored. I don't like what I see but I don't have enough experience to make that judgment call. 

I was getting ready for a pain job anyway, looks like its gonna be engine out 😀

[tech71]

11 hours ago, Summit321 123 said:

I was getting ready for a pain job anyway,

Thats one way of putting it.