What would you do take a look

[lcu1646]

Just completed disassembling my 110 hp johnson v4 due to bad cylinder. I deglazes the cylinder walls and for the most part it came out pretty good at least in the area I was first worried about but the one thing I didn't noticed was the 1/4" long gouge just below the exhaust port! I have my thought on it but I want to see want everyone else would say or do if it was there motor. Please take a look at the picture and let me know

Thanks
:fish2:

 

[Lone Duck]

Re: What would you do take a look

I would smooth out the bottom edge of the port using a dremel tool. Also slightly smoothing out the edges around the gouge and into it slightly so there is no danger of any loose material breaking out. then rethatch it. The result would be that the rings would not bind. The timing of the release of the exhaust gases would be minimal. In fact after having another look , I would also do the top edge very slightly.I have ported chainsaws that way.

 

[lcu1646]

Re: What would you do take a look

Lone Duck,

Thanks for the reply that was my first thought but I wasn't sure if that gouge below the exhaust port would cause any issues. What would be the down side of using it like the way it is if I did cleaned it up? To me its at the bottom of the stroke and the compression at this point is nothing can you give me your thoughts or do you think I should just have it re-sleeved. But I don't see wasting the money if it really won't matter

 

[lcu1646]

Re: What would you do take a look

Anyone else have any ideas on what to do clean it up or re-sleeve? Anyone else come across a problem like this and just cleaned it up and ran it?

 

[Lone Duck]

Re: What would you do take a look

Lone Duck,

Thanks for the reply that was my first thought but I wasn't sure if that gouge below the exhaust port would cause any issues. What would be the down side of using it like the way it is if I did cleaned it up? To me its at the bottom of the stroke and the compression at this point is nothing can you give me your thoughts or do you think I should just have it re-sleeved. But I don't see wasting the money if it really won't matter

I don't see a down side as long as you are meticulous during the clean up. When you think it looks good, clean up the edges with 1000 grit wet dry sandpaper .

 

[emdsapmgr]

Re: What would you do take a look

While not a good thing, I don't think that gouge will affect running. I'd be inclined to run it. Long-term it can be a problem, but it could take years to show up. Basically, exhaust gas will get blown down into the gouge-that opening is now a direct passage to the top ring. Over time (perhaps years) the ring can start to accumlate excess carbon build up in that area of the ring and piston ring groove. Could eventually result in a stuck ring. I doubt you will see any compression issues between cyls due to that. Not sure that I'd enlarge/smooth that gouge any.

 

[Lone Duck]

Re: What would you do take a look

While not a good thing, I don't think that gouge will affect running. I'd be inclined to run it. Long-term it can be a problem, but it could take years to show up. Basically, exhaust gas will get blown down into the gouge-that opening is now a direct passage to the top ring. Over time (perhaps years) the ring can start to accumlate excess carbon build up in that area of the ring and piston ring groove. Could eventually result in a stuck ring. I doubt you will see any compression issues between cyls due to that. Not sure that I'd enlarge/smooth that gouge any.

The reason I say smooth the edge is get rid of the weak edge where the material is thinner with no other material behind it. Don't want them to break loose and score piston rings and cyl wall.

 

[lcu1646]

Re: What would you do take a look

I would agree on hitting the egdes to remove any of the loose metal and cleaning up so nothing comes loose while running the motor. I am shocked there hasn't been someone saying to resleeve or bore it out! I thank you guys for taking a look and giving me another opinion on this subject. emdsapmgr thank you for your explanation on what will happen over time.

Thanks again Lone Duck and emdsapmgr

 

[Lone Duck]

Re: What would you do take a look

I would agree on hitting the egdes to remove any of the loose metal and cleaning up so nothing comes loose while running the motor. I am shocked there hasn't been someone saying to resleeve or bore it out! I thank you guys for taking a look and giving me another opinion on this subject. emdsapmgr thank you for your explanation on what will happen over time.

Thanks again Lone Duck and emdsapmgr

Your welcome! Don't forget to do the cross thatch when you are done.

 

[Faztbullet]

Re: What would you do take a look

It maybe ok as long as its below port and it will affect the piston/rings as emdsapmgr posted. If it was one of my customers blocks it would get bored oversize to clean it up if possible. From your picture please dont tell us you deglazed block with crank installed , if so the center main and lower main bearings are full of honing material and it cannot be wash out while assembled.:blue: Also that is not a good or close crosshatch in cylinder......

 

[emdsapmgr]

Re: What would you do take a look

The ring is designed to span the entire width of the port openings without catching on the bottom/top port lips. So it should not be a problem with this small gouge.