Smoking

apeonwheels · Post by **apeonwheels** » Sun Nov 15, 2015 2:55 pm

Hi All,
After I managed to fix some oil leaking due to the cam position failure (see my earlier post: http://www.honda305.com/forums/first-st ... 35775.html), I have a new issue: a strong smoking that I expected to disappear after a couple of mins running but it didn`t. I don`t know if it burns oil or the mixture is too rich and that is the reason for the smoking. The mix is rich for sure, because it is not running when the choke is on. The carbs are rebuilt with aftermarket kits, the float valve is set to specs. The ignition and cam timing is correct. The oil rings are supposed to be sealing, they looked new when I assembled them in and the gaps were within the specs. I attach some pics about the pistons and rings that I made when I put the engine together. Since these engines don`t have valve seals, they should be ok, too. Any guess where the smoke is coming from? Another, perhaps related question: where is the breather pipe on the cylinder cover supposed to be connected to? I couldn`t find any inlet on the air filter. Thanks for all comments, any thought might be useful, I really hope that I don`t have to pull apart the engine again.

sixtiescycle · Post by **sixtiescycle** » Sun Nov 15, 2015 4:31 pm

Just curious if you set your ring gaps 120 degrees apart from the others? Your last picture shows the top compression and second scraper ring gaps almost in line.

The breather hose hooks to nothing, it comes down the back of the head into a clip mounted to the left side of the cam chain tensioner, continuing through the square notch in the valley cover to the bottom of the valley where it turns 90 degrees to the right under the valley latch bracket and terminates just through the hole into the kickstart/alternator void.

apeonwheels · Post by **apeonwheels** » Sun Nov 15, 2015 4:49 pm

Yes, I positioned them 120 degrees apart. Thank you, now it is clear how to route the breather hose.

SMBH · Post by **SMBH** » Sun Nov 15, 2015 6:10 pm

Just a thought can you fit the piston rings upside down on a Honda like this, many years ago I put some piston rings in a unit 500 Triumph upside down and had a lot of oil burning and crankcase pressure you see the rings were tapered just a thought.

As I see it the only way oil can get into the combustion chamber is past the rings or past the valve guides.

apeonwheels · Post by **apeonwheels** » Sun Nov 15, 2015 7:21 pm

Thanks for your tip, I don`t think they are upside down. Now that I played with the carbs while the engine running and made a little ride (it`s non-operational and cops are hanging around) the smoking seems much less serious, probably it requires a bit longer for the rings to wear in, hopefully it gets even better. The mixture is super rich though, fuel is dripping from the left spark, the right is covered with soot... Any experience with these aftermarket carb-rebuilding sets? Perhaps it would be better to put back the original needles and jets..

Tim Miller · Post by **Tim Miller** » Sun Nov 15, 2015 7:58 pm

Once the cylinders become glazed from a overly rich fuel mixture, game over. You will need to re-hone cylinders to cut past glaze in order to ever reseat rings.

Tim

apeonwheels wrote:Thanks for your tip, I don`t think they are upside down. Now that I played with the carbs while the engine running and made a little ride (it`s non-operational and cops are hanging around) the smoking seems much less serious, probably it requires a bit longer for the rings to wear in, hopefully it gets even better. The mixture is super rich though, fuel is dripping from the left spark, the right is covered with soot... Any experience with these aftermarket carb-rebuilding sets? Perhaps it would be better to put back the original needles and jets..

apeonwheels · Post by **apeonwheels** » Sun Nov 15, 2015 8:20 pm

Hopefully I haven`t reached that point. But I take apart the carbs and set the correct mixture to avoid the cylinders to be glazed further. Thanks, Tim!