Winter rebuild project - Phase 2

In communiqué <Q94TghDf35$GFwq$@ps-fisher.demon.co.uk>, Pete Fisher <Peter@xxxxxxxxxxxxxxxxxxxxx> cast forth these pearls of wisdom
In communiqué <MPG.2169aa6ccf52e95498970c@xxxxxxxxxxxxxxxxxxx>, Lozzo <lozzo@xxxxxxxxxxxx> cast forth these pearls of wisdom
Pete Fisher says...

Engine out later today with luck and I will probably will at least lift
the head myself and possibly the cylinder before taking it to SWK. They
can also check the operation of the oil pump. Hopefully a phone call to
Uncle Bob Wright will confirm that he can supply a new
cylinder/piston/gaskets. Won't try to re-assemble it myself as the
workshop manual warns about getting the 'squish' exactly right with a
dial gauge (six thickness values of base gasket available).


There was approximately 650 cc of coolant in the system. Capacity is 1100 :(

The air filter box wasn't a very good fit on the carb intake. So a slightly weak mixture can't be ruled out.


Engine out. Much easier than a Nordwest. I wouldn't attempt anything bigger single handed. A bit of a j-j-jiggle in the last stages, but I now see that by taking the bolt-on side stand mounting bracket/lower fairing mounting point off on one side it will be much easier to get back in.

Definitely plenty of oil in the pump and supplying it but I will have to work out a way to test it.

So here are photos of what you can see through the exhaust port with the power valve wound open.

http://www.ps-fisher.demon.co.uk/pickchurs/gfr_rings.jpg
http://www.ps-fisher.demon.co.uk/pickchurs/gfr_skirt.jpg

All too familiar. Looks like a classic heat seizure with trapped rings to me and a big 'pick up' streak on the skirt. What do you reckon Lozzo?


On the Rotax I would consider dressing the ring grooves and skirt with a swiss file. Treat it to new rings and bung it back together. The rings are delicate and thinner than a very thin thing though, and this little beast probably has a nikasil bore. Unless I am really lucky no doubt that will be FUBAR.

Still not sure whether to lift the head and cylinder myself or just take the whole lump to Revs.

My demeanour has not been improved by breaking a tooth while chewing on some hard chocolate[1] as comfort food, so first call tomorrow has to be the dentist anyway. After that I probably won't be in the right frame of mind for carefully dismantling a delicate 2T top end.


[1] No, not Yorkie, but 85% cocoa Green & Black's Organic.


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+-------------------------------------------------------------+
| Pete Fisher at Home: Peter@xxxxxxxxxxxxxxxxxxxxx |
| Voxan Roadster Gilera Nordwest Yamaha WR250Z |
| Gilera GFR * 2 Moto Morini 2C/375 |
+-------------------------------------------------------------+
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