Bore lip damage from bent valve

[Haakon]

What does the brains trust think of this? 2 litre Megane that had a belt skip some teeth and took out all 8 exhaust valves. In addition to some essentially cosmetic marks on the pistons, each valve has tickled the lip of the bore.

There is a slight raised edge on the burrs.

Now im not worried about the pistons, but should I attempt to knock the raised edge off on the deck, or just let the gasket take it up?

 

[COL]

I would get rid of the burr so that the head gasket has the best chance of sealing without being deformed. That little chip won't effect the operation of the engine as the piston rings don't go that high. worth.

 

[PeterT]

I agree. Use a small smooth file to make the surface flat, otherwise it will cause a hotspot.

 

[DoubleChevron]

you can see how high the ring goes in the bore by the staining at the top. I can't see how that effects anything (so long as you don't have a sharp edge that could get red hot and cause pre-ignition).

uncle tonys garage did a video a few months back about a motor that pinged all the time ... that he could never fix ... when he pulled the head off he found the motor had a casting flaw that had left a sharp edge in the combustion chamber.

 

[jaahn]

Yes as the others said. Remove any raised area, do not remove more that that or make more of a depression on the sealing area. A fine file or some fine emery held against a flat metal bar. The same for the bore marks, remove any high spots or edges with a bit of fine emery. Same with the piston tops. A bit of careful work and it will be good as gold.

Some years back I had a small bus which siezed the diesel engine after blowing a coolant hose on the highway. The bores were badly scored as were the pistons and rings & lands. It would have been very expensive to flat tray it home as it was several ton and longish. To enable me to move it in the end, I pulled the pistons out honed the bores to remove the raised metal, Pried out the broken trapped rings, fitted new rings and gasket and drove it. It started OK and ran OK with only a bit of oil smoke. I sold it for parts with a crook engine. But the guy who bought it thought the engine sounded good and might use it. I remined him it needed a complete rebuild as I had told him. But I was surprised how good it sounded and went with the grooved bores ??? Engines can accept some imperfections with little effect. .
Good luck jaahn

 

[RINGER]

I kind of agree with others but would tend to be reforming as much as possible then cleaning up, removing minimal, if any, material.
Mild (soft) steel bar hammered where appropriate is what I'd use until nice & flat/round.

 

[Haakon]

A very fine file very carefully used neatly knocked the raised bits off. Sorted.

I’ll try just using scotchbrite and brake cleaner, and if need be some 1200 emery paper on a flat block should clean it all up.

 

[driven]

Go the cross hatch pattern