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[1967Brutus]

Ravika is now in operation for a bit more than 2 years, and has now about 120 runhours under her belt.

In this time I had ONCE before that a speck of dirt blocked the suction valve of the feedpump, rendering it non-functional. That was about 50 hours in, IIRC.
That was really a tiny speck of dirt.

Last outing, the pump did not work again, so I took the pump apart, and this time I found quite a plug of fibrous material sticking to the suction valve.
Weird.

So I emptied the hotwell, just to have a look, and I found this:



That really is a shocking amount of dirt, I have never seen such before.
The entire amount of water gets refreshed approx every 5 running hours, and I always do a visual check, and in those 2 years I have never before seen even the slightest bit of visible dirt.

It looks like plant or tree seeds or something. I really have no idea.

[DBS88]

That really is an impressive amount of run time, well done. I have no idea what the mess is in your water, would an inline filter help? or would that just get blocked anyway? Maybe there's nothing to do unless the problem keeps re-occurring?

[1967Brutus]

My hotwell is an open top basin, and difficult to close off.

It is very possible that plants were shedding seeds during the "before last" outing, when the boat was in open air for about 6 hours.

Usually, outings are only 1 or 2 hours and not so much plantlife in the neighbourhood.

It's all I can think off.

But yes, it is quite a bit of runtime, and to be honest, I have yet to notice the first signs of wear related deterioration, on the contrary, I have the impression it still is improving, judging by its low speed running. I would have to estimate, but I think I am getting close to 120  RPM as lowest stable running speed.

[TomF]

HELP REQUIRED WITH REVERSING GEAR.


I needed to replace the screws at the bottom of the concentric shaft with flatter screws. Unfortunately, when replacing with new screws, the crankshaft moved in relation to the concentics - now the engine is only running in one direction. Does anyone have a suggestion on how to "re-adjust" correctly? Thanks.





 

[1967Brutus]

Strictly theoretical: Both cams should be 90 degrees off from the corresponding crankthrow, each cam to one side.
They should basically be opposite of each other. So if the good running direction, if those cams are OK, then the other cam should be precisely opposed.

It can be that best performance is had with the cams 5 or 10 degrees off of "theoretical", for example to compensate for play in the mechanism.
That is a matter of testing, which for convenience can best be done on compressed air.

[KBIO]

Hello !
Brutus said it all [size=78%] ! The screws that you showing (arrows ) are guide screws to maintain the eccentrics in place. The Allen screw shown in the first pic is the one , you turn it for adjusting  the eccentrics (made of one piece most probably) . Piston at DHP (the way it is) and the Allen screw at 90° .  Looking at the photo , you can leave the piston in high position and rotate the eccentric to the right. Stephenson is in the right position . That should work on such engine. [/size]
There is probably a post describing how to adjust eccentrics on this forum....
Let us know !

[ooyah/2]

Tom,
Can you confirm whether you have fixed the running order of your engine, or is it still only running one way ?
Does the Mild steel eccentrics have only  one grub screw on the boss as show on your pic ?.
Please let me know and I shall help you to retime the engine.


George.