1961 evinrude Carburetor problems

[waterlogged59]

I recently got my hands on a 1959 Duracraft Boat in great condition with a 1961 evinrude 40 HP Lark 4 engine. Everything has been rebuilt but am having trouble with the carburetor. I can get the engine to fire up but will spit gas through the carb. I Even with the choke off and the engine on lean it still spits gas heavily. I am thinking its flooding the engine but not sure. I decided to take the float bowl off and take a look at the float. Its orange cork i believe. I tested it in warm water to see if it would float and it did. So i am not sure what would be causing the excessive gas. I am so close to put this boat in the water but this gas problem is holding me back. I NEED HELP!!!!

 

[Willyclay]

Re: 1961 evinrude Carburetor problems

I had to rebuild the carburetor on my 1959 Johnson 35HP(same as yours) three times before it would idle correctly. Old gunk is hard to remove. Good luck!

 

[samo_ott]

Re: 1961 evinrude Carburetor problems

Sure sounds like a dirty carb.

 

[tashasdaddy]

Re: 1961 evinrude Carburetor problems

could be either very dirty carbs, or bad reed valve in the intake. please post pictures of you duracraft. i have a 1956 that i have done.

http://forums.iboats.com/forumdisplay.php?s=&daysprune=&f=293

posting pictures: you can up load to a free service like photobucket.com then you choose the pictures you want( clik the little box at the bottom left of the picture) scrool to the bottom of the page, clik generate html, it will take you to the next page, scroll down to thumb nails clik on that and copy, then insert it into your post.

also if you are planing on posting pictures, you can use the Blue post reply or the go advanced, there you can upload directly from your computer. besure you pictures have been resized to fit the format. 640x480 max.

 

[waterlogged59]

Re: 1961 evinrude Carburetor problems

Well I took the bowl off and the float off yesterday while i wait for the new one. While taking the float off the needle valve i am guessing just feel out of its housing. Is it supposed to be in there that loose?. Also How would i find out if its gunked up by looking at it. Also you mentioned something about a reed valve. where is that located. I will try to snap some pictures today or tomorrow and post them on here so you can get a bettter look.Thanks for you help. By the way Who ever has the duracraft rebuilt pictures; the boat looks great. Good idea with the bar seats.

 

[Chris1956]

Re: 1961 evinrude Carburetor problems

Waterlogged, The reed valves are under the carb base. You can test them by cranking the motor with the electric starter, carb off and put your hand over the carb intake. If you feel sunction the reeds are OK. If you feel pressure, the reeds are bad.

 

[wbeaton]

Re: 1961 evinrude Carburetor problems

First, buy a manual. Not to be rude, but I think you need it. It will teach you the basics and show you what to do. We all own and use them.

If it actually spits gas then I'd be real interested in looking at those reeds. A carb shouldn't spit anything dirty or not. I'd also spray all the engine seams and under the magneto with WD40 as the motor is running and see if that makes any difference. If the lean adjustment doesn't stall the engine then the carb must be dirty. Rebuild the carb regardless. Use carb cleaner and compressed air. Make sure you clean out every port and passage. Check that the needle valves are not damaged.

Since the float is out, its a good time to either reseal it (I use polyurethane) or replace it with the new plastic foam type.

Keep us posted on your progress.

 

[BillP]

Re: 1961 evinrude Carburetor problems

Those are the same carbs used on bazillions of OMCs and spitting gas out the carb at idle speed when the airbox is off is normal...even when new. I can only guess that the intake air velocity into the carb drops when the airbox is off and makes the problem look bigger than it is. If the motor is running ok relax. If in doubt take it to a shop that knows old OMCs and get their expert advice before changing parts.