|EXHAUST SYSTEM FOR EARLY TWO STROKE
Post Number: 13
|Posted on Tuesday, May 21, 2013 - 04:46 pm: ||
Am restoring a 2 stroke, 3hp Watermota engine for use in a small dinghy.
Am told that while an L shaped steel tube may be adequate for display purposes, to obtain best engine efficiency, some level of back pressure in the exhaust system is needed. The existing exhaust is just a 31/4 inch bent tube, 12 inches long.
Secondly, to prevent any water getting back to the piston/combustion chamber, what level above the exhaust flange should this be set?
If any member could kindly offer advice and help on these two queries, I'd be extremely grateful.
Post Number: 699
|Posted on Tuesday, May 21, 2013 - 10:03 pm: ||
You can run the engine with a ht exhaust no problem, except that you'll wake up the whole neighorhood with the bark.
Some form of muffler should be used.
Fr a wet exhaust, where you dump the engine cooling water into the exhaust stream, jst make sure that the water injection pint is blow the level of the exhaust port, and is pointing into the exhaust pipe gas flow , rather that a simple Tee fitting.
The best of all is a wet muffler, which is set p to drain about 1/3 of the water back into the lake, theother 2/3 goes out the exhaust port.