SailNet Community banner
1 - 9 of 9 Posts

·
Remember you're a womble
Joined
·
2,328 Posts
Discussion Starter · #1 ·
So I'm at the boat trying to adjust the timing. Dumb question time. If the injection pump squirts fuel after the timing mark has gone past, is it retarded and I need to remove shims, or advanced and I need to add them?
 

·
Remember you're a womble
Joined
·
2,328 Posts
Discussion Starter · #3 ·
Well turns out it needed less shims. Adding shims moved the timing even further off. Managed to get it close (within a few degrees) and that was the best I could manage since there are no shims at all there now, runs all the way to the redline now with no white smoke, and started on the button. That'll do.
 

·
Registered
Joined
·
2,063 Posts
Well turns out it needed less shims. Adding shims moved the timing even further off. Managed to get it close (within a few degrees) and that was the best I could manage since there are no shims at all there now, runs all the way to the redline now with no white smoke, and started on the button. That'll do.
Congratulations Paul on dueling this dragon and winning.
 

·
Remember you're a womble
Joined
·
2,328 Posts
Discussion Starter · #5 ·
Here's a blast from the past. I've been having ongoing problems with this damn engine. Anyways, I took it into a mechanics to take a look (actually, this is the third mechanic I tried, the rest were absolutely useless).
I'd always suspected the timing might be an issue and turns out it is. The interesting thing is, the injection pump appears to have grown larger when it was rebuilt, it simply cannot be pushed down far enough to get the timing right (which is what I originally thought). I called the shop that rebuilt it, and so far they have no possible idea on how that could happen. The mechanic has even tried taking the roller off another pump in case somehow the wrong one was put back, but no change.
 

·
Registered
Joined
·
3,268 Posts
Had a similar problem a few years ago on my previous boat, tried everything on the injector timing. bought a new pump because it cost less the they wanted to rebuild. kept removing shims until it was in time and ended up with no shims. by that time i was tired of testing and just left it and it ran good. asked the mechanic at the Yanmar dealer and he did not know why but said he has had a few others that way.
 

·
Remember you're a womble
Joined
·
2,328 Posts
Discussion Starter · #7 ·
And gets even stranger. The mechanic was unable to get the engine timed, eventually resorted to shoving a scope down the injector hole and observing the piston. Seems the timing marks do no correspond to the actual position of the piston. They got the injection pump timed to the piston, but it's still not right which would indicate that somehow the timing gears in the engine are not aligned properly. Basically there's not a hope in hell I could have got this timed myself. Anyways, after a rather significant invoice for the work so far, I've called it a day. The engine ran OK for 45 minutes or so at 3000rpm with just white smoke - I couldn't get above 2400rpm without clouds of black smoke before. It's good enough to move the boat nearer to home and then I'll have to take the timing cover off and see what is going in inside.
Injector tested OK, they replaced the front and rear combustion chambers and tested the compression - that's all OK at least now so not looking at a rebuild.
 

·
Registered
Joined
·
4,721 Posts
Reminds me of back in the day when we advanced the cam a tooth looking for performance. (Flathead Fords) The dots can be tricky (not straight cut gears )and the cam rotates as the gears slide/mesh. Seems to me that it is similar but I've only done a couple of yanmars so no expert. There used to be a guy at Wilson and Proctor Damm good, check it out.
 

·
Remember you're a womble
Joined
·
2,328 Posts
Discussion Starter · #9 ·
On a 1GM10, maybe they extracted an extra 1/20th of a horsepower :D
I've spent enough at W&P, 2 injection pump rebuilds (different engines) and an injector rebuild.
 
1 - 9 of 9 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top