Carbon streaks on cylinder?

[Mycamaro_68]

The suspense was killing me so I tore it down after work tonight. The streaks on the cylinder seemed like highly polished areas. I could not feel any scoring at all. But the ports look terrible.

Nasty silicone on muffler, I hate this stuff.


One base bolt not even close to tightened down.


No base gasket. Not sure what kind of sealant but it was NOT hard to pop the cylinder free.

 

[Mycamaro_68]

Pictures of the bore and the ports.

 

[Mycamaro_68]

Wear on piston, likely from the chip on the intake port.

 

[Mycamaro_68]

This is after a shirt time with some 120grit sandpaper and some scotch brite.

 

[Mycamaro_68]

Just for *s-words and giggles, because I have one here, this is the difference between the piston that was in it and a Dolmar 7900 big bore piston. Interestingly enough the Dolmar cylinder looks like it would be close to bolting right up. I didn't have time to get measurements yet.

 

[andyshine77]

WOW that cylinder was hacked up! The plating may be a little thin, but likely still very usable. I would reshape and chamfer the ports. Sealant on the exhaust was a nice touch.

 

[P.M.P.]

So someone just throws a new piston in it
( cheaper the better) and doesn't attempt to clean the aluminum off the cylinder
( fukit who's gonna see it). But grinds on it a little

 

[drf256]

That’s some bad Dremel-ing.

You may be able to reshape them ports and chamfer. Still looks like you’ve got some transfer on the walls to me.

At least it appears the timing wasn’t altered.

 

[Al Smith]

IMO if you got into that thing with some Craytex and do some cleaning up of the ports it most likely will be okay .The neat thing about Craytex is it doesn't cut that fast and won't flake off the plating like a toothed cutter could .It's relatively inexpensive bought in bulk through McMaster -Carr.The shapes and the mandrels are sold separately .

 

[Al Smith]

I guess I just don't get the idea about some people slobbering on some type of sealant with what appears to be a paint brush .If a gasket is supple it doesn't need any plus a gasket is easy to make if you don't have one handy .
I've made gaskets for the last 50 years from carb gaskets to manifold gaskets and they all worked .Fact the old Oliver crawler I made the manifold gasket over 35 years ago and it hasn't failed yet .Like they say "it ain't rocket science ".

 

[blsnelling]

Looks like transfer under the exhaust port. Also, the shape of the exhaust port needs some attention, as well as the beveling.

 

[Mycamaro_68]

Pull the topend. I have only seen 1 other 54mm with 2 ring piston oem. Most with 2 ring have had the 660 piston put in. I have done that.

Dont know if pic shows stock look on the 505. Sorry nope. Here a fubbared 2083 of mine I found.

But that cyl IMO is crap had a 2083 come in like that with crap porting. I tried my best to clean this 2083 cyl back up and then the fing crank broke.

Toss that golf piston and grab a meteor 66. If you can get the cyl cleaned up.



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Is the Meteor 066 piston a drop in replacement or does it require modifications?

 

[Cut4fun]

Is the Meteor 066 piston a drop in replacement or does it require modifications?

Need to open pin bosses on 66 for rod. Easy peasy.

BB372 was drop in but no good afm pistons I trust back then. They were good for stock though.