Hi all
Having just completed a full service of the engine and replaced all the usual anodes ,impellers and filters etc. all relatively simple jobs but the one job that i neglected to check last season was the exhaust elbow .Yanmar did a complete check on the engine 3 years ago and replaced the elbow ,so to see it completely desintegrated away was a bit of a shock.What happens is you get water back up into the cylinder head and the head gasket blows and this will wreck your engine.
At the cost of £142.00 i feel money well spent, so if you do your own servicing check this bit too.

Peter Lowry
Cleo.

Trevor Baker (22/134 Wight Seal) had that problem on his 1GM10. The only symptom was that he was only getting about 1hp out of the engine! The elbow looked fine from the outside. Inside the sleeve that should direct the cooling water down away from the engine had developed a leak in the weld that let cooling water back into the exhaust port resulting in a blockage of black concrete (presumably salt and carbon) reducing the port to about 1/4 inch diameter![img]http://i144.photobucket.com/albums/r189/geoffatstanpit/Yanheadold.jpg[img][/img]http://i144.photobucket.com/albums/r189/geoffatstanpit/Yanexhaustnew-1.jpg[/img]
If that worked OK you should have pics of the elbow and port as was and the same new.

Well - it nearly worked. We got the pic of the old elbow and the new head. This should give the pix of the new elbow and the old head!

Hope that works better

Geoff Harwood