I have a new engine. I took mine apart yesterday to have a look. Aside from needed a new cylinder and piston I would need a new crankshaft, the valves looked pretty knackered too. Whatever I did to the carburettor wouldn't stop the bike from cutting out whenever it warmed up and it would overheat after an hour at riding 30 mph. I think it was best to just start fresh and treat this new engine well from now on. 4 gears and 25 more cc's was pretty tempting too! Apart from hopefully not having an engine that will break down all the time I'm hoping this will be the end of having to source out spares, trawl through markets on false promises, find mechanics and generally go through the intense mind fuck it is trying to deal with all this in every large town in every West African country I've been in. I haven't had the best experience with the mechanics here so far and I'm starting to lose my temper with people quite easily. Things are different here, but it will be nice to be able to step back from the chaos for a bit.
Special thanks go out to all the people who've given me engine and mechanical advice during the death, and a big thanks to Kofi and his brother (sorry, I don't know how to spell your name) for letting me stay at their place this last week and helping me find the engine.
Onwards!
Hi Liam,
ReplyDeleteIt's great to hear that you've got a new engine sorted out and running smooth. I just think that you should still beware of any fuel system problems. I had a look around online and a common suggestion to do with overheating in air-cooled engines is to make sure that you stay moving to keep airflow over the engine - so if you're sure plenty of air was getting to the engine before then I really advise that you make absolutely sure that your carburetor is not running lean at higher revs.
Since you're feeling a bit more confident in the engine now, I just suggest you briefly blast it before you next stop for the day, just long enough to burn any soot off the plugs if it were running lean so you can check their colour later or the next morning. (Unless it's already too hot by then of course.) If they're still sooty or a deep dull copper, then you can finally relax. I know you've checked the plugs already, but carburetors work differently at different air flows, and you want to make sure it's at least ok at higher rates of airflow.
The overheating could have been caused by the exhaust valve not fully closing though, pulling exhaust fumes back into the engine. So the chances are it will be fine anyway. Can't hurt to check now that it's running better, right?
Best of luck,
Berin
I have been following your blog and glad to know that you have a new engine installed. I have some familiarity with Honda engines myself and my past experienced instinctively tell me there me there was more to the old engine than just piston etc. I had an engine newly overhauled and it seized shortly after a few miles riding to work. It turned out that the oil pump was worn and as a result it was not delivering sufficient oil pressure. My feeling is, from your description, is sounded like oil pump and its oil passage oil delivery issues.
ReplyDeleteI am enjoying your adventures and also your write ups. Please keep them posted.
If you ever travel to San Jose, California, you are welcome to use my garage and a little R&R here.
Safe riding.
Sim