[wseith]

OK, i have tried everything i know to get this motor to run smooth.Unfortunatly i dont know that much. Here is what i did so far. Rebuilt carbs,replaced powerpack and coil,set points,troubleshooted fuel pump per manual and so on. The motor when started up for about 10 seconds runs smooth. After that it starts missing and coughing and it smokes pretty bad.My compresion is about 105 on all cylinders oil is leaking from gear box.I have spark on all cylinders i have a vented gas tank and new gas mixed at 24:1. I dont know what to do next. Ive never had this boat on the water. I am running it in a barrel of water with the shaft approx. 2 feet submerged and the barrel is about 3'x3'. It seems that the engine is running rich and coughing on its own exhaust. Could the way i am running it cause this. Well as you can see im frustrated and about to pitch the engine. If anybody has any advice on where to go from here it would be much appreciated.

[tashasdaddy]

1964 and later are 50 to 1 mixture. have you done a link and sinc? how have you adjusted the carbs. do you have a good manual

carb adjustment:
http://www.iboats.com/bbboard/bbBoar...;gpid=8 18802
manual:
http://www.kencook.com/evinrudejohns...ors&orderby=hp

there are 4 manuals for your year, clik the model number and it will give you the correct manual number, and you can look on ebay.

after getting it running do a decarb on the engine as it probably never been done.
http://www.boatsetup.com/Decarb_Carb.html

ya'll were typing whil i was putting this together.

[F_R]

YES! The way you are running it. Right off the bat, it is not supposed to be running on 24:1 It is supposed to be 50:1 So you have a bunch of excess smoke and plug-fouling oil.

Secondly, running in any kind of tank causes smoke to be sucked into the motor intake, which causes rough running. Even the well vented commercial shop tanks usually require running with the hood off. Try blowing the smoke away from the motor with a large fan, might help some. But the real answer is get it on a boat in the water.

If you want to pitch the motor, strap it on a pallet and send it to me.

[wseith]

Originally Posted by tashasdaddy

1964 and later are 50 to 1 mixture. have you done a link and sinc? how have you adjusted the carbs. do you have a good manual

carb adjustment:
http://www.iboats.com/bbboard/bbBoar...;gpid=8 18802
manual:

Ive ran it on different mixtures from 50:1 to 24:1 im not sure how to do a linc and sinc and my manual is a seloc

[DHPMARINE]

10 seconds of running good then bad is hard to diagnose.You can do longer than that with a full carb of gas.and it will run 3 minutes or more without water (yes damage will be done to the water pump,but it'll run).

Are you aware of the manual overide on your electric choke? Three settings.

DHP