Damaged Nicasil

[Skar]

How much damage is ok....

Just got the head off my Imola, looks like the ring peg came away.

Damage is:

Small nick at the inlet port.
Piece of ring embedded into cylinder head and more debris in top of piston at exhaust port side.
Small nick on exhaust port.
One very small groove running to exhaust port down barrel (can feel it with a fingernail and see it in certain lights).

Money is tight atm, think I can get away with it?

[AUSSIE]

I'd probably go for a new piston and rings, see how the head cleans up with emery/ wet &dry, maybe get it reprofiled, at worse new head.
dont worry too much about inlet nick, think about getting the barrel tuned as this may be a way to get exhaust nick removed. if score is as tiny as you say f just keep eye on it and run it as is.

[coaster]

I'd probably go for a new piston and rings, see how the head cleans up with emery/ wet &dry, maybe get it reprofiled, at worse new head.
dont worry too much about inlet nick, think about getting the barrel tuned as this may be a way to get exhaust nick removed. if score is as tiny as you say f just keep eye on it and run it as is.

I'd agree with all that, my Mk1 muggy has had an 8mm wide gouge in the nicasil from the top of the bore to the exhaust port as a result of a holed piston for around 6000 miles now and still going strong.

[paulmgreen]

Yep ..... What was said above sounds ok!

[smoore-gt225]

hi sorry about getting in on thread does everyone think this will be ok with a quick hone, it had only done 100 miles after new piston and 60mm cranck fitted and a piece came off the top of piston, no-one seems to know what might of happened.
someone said bad fuel,another said faulty piston??

cheers steve

[coaster]

If it's localised I'd just smooth the score with some fine wet & dry to blend it in, my Mugello barrel was worse than that

[smoore-gt225]

If it's localised I'd just smooth the score with some fine wet & dry to blend it in, my Mugello barrel was worse than that

hi coaster it is a mugello, there is a score as you can see and a tiny mark just below exhaust port, i am going to give it a go today and see what happens
cheers steve

[soullad]

Imola owners - why not consider the 64MM RD 350 LC piston, as used in Rich T old GT 186 kits, with full kits available for approx £40, loadsa oversizes and better quality than the standard Meteor versions. Needs to run with a longer rod ideally thou, as I believe they have an approx 30mm crown height - no pain no gain as they say?

[mawso]

why not consider the 64MM RD 350 LC piston - Are they 16 or 18mm little end?

Was selling a knacked Imola barrel, but got a good offer for full SR190 engine, so am planning to do something with the Imola now. SR went with a new RD400 rodded crank too...which would've suited what you're suggesting too!

[soullad]

16mm
If you've fitted the longer rod to take a TS185 piston for your SR based top end then your crank is ideal for your Imola + RD piston too . A steel liner is approx the same price as nicasil too, again there are pro's and cons but with oversizes upto 66mm maybe the RD piston + steel liner will work out more economical in the long run?
The choice as they say is yours .................