1966 33hp Evinrude. No power. Stalls at full WOT

seedpws · #1 July 23rd, 2007, 04:47 PM

I have a 1966 33hp Evinrude. It wouldn't run when I bought it so I rebuilt the carb. It now runs good at idle. When I have it under power it will run good in idle. When I open it up it doesn't have much power. I noticed it runs almost the best when the high speed is set all the way in or maybe 1/2 a turn out. Also to start the boat the low speed has to be in about 1 1/4 to 1 1/2 turns out. Then to get the most speed is has to be moved out to get some kinda power. Also at WOT the boat will start getting up to speed and then die. In order to start it you have to pump the ball and it is empty. What do you think it is and what should I check. Also the high speed adjuster doesn't seem to do anything. Let me know
Thanks

tashasdaddy · #2 July 23rd, 2007, 05:39 PM

open the vent on the gas tank, the ball is suppose to be soft after the engine starts, it just pumps to the carb to start. what do the coils look like, here are the proper carb setting, courtsey of the great Joe Reeves.

(Carburetor Adjustments - Two Adjustable N/Vs)
(J. Reeves)

Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow speed = seat gently, then open 1-1/2 turns.

Setting the high and low needle valves properly:

NOTE: For engines that DO NOT have a shift selection, obviously there is no NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low speed needle va /lve adjustment.

(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to full throttle. In segments of 1/8 turn, wating for the engine to respond between turns, start turning in the bottom high speed needle valve. You'll reach a point whereas the engine will either start to die out or spit back (sounds like a mild backfire). At that point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest setting.

(Low Speed) Slow the engine down to where it just stays running. Shift into neutral. Again in segments of 1/8 turns, start to turn the top needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running. Eventually you'll hit the point where the engine wants to die out or it will spit back. Again, at that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustments, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway

seedpws · #3 July 24th, 2007, 11:46 AM

I adjusted the carb as stated before. The motor will shut down at WOT and doesn't have much power. The spark looks good.

seedpws · #4 July 24th, 2007, 11:56 AM

Also I noticed something when I put it together that I didn't notice before. The electric choke was broke so i left it off the carb. Also Before I never noticed the plate in the carb on the front of it that you use to choke it. Before when you closed it it closed all the way and when you opened it it opened all the way. Now I have to put it all the way open and then it says that way. Is this correct or could this be a problem? Thanks

tashasdaddy · #5 July 24th, 2007, 12:35 PM

the front carb butterfly is the choke plate, when running needs to be all the way open, if not it will flood the engine and cause poor performance. have you checked the link and sinc of the spark and the carbs. could be that the timing is not advancing with the carb, thus flooding the motor. have you checked your compression, if so what are the numbers?

Molaker · #6 July 24th, 2007, 12:45 PM

Quote:

When I open it up it doesn't have much power. I noticed it runs almost the best when the high speed is set all the way in or maybe 1/2 a turn out

You also questioned the manual choke operation. The choke has a manual operating lever which has a detent for 1/2 choke and then full choke. This overrides the choke solenoid operation. Could it be you have had the choke in the 1/2 choke position? This could cause low power at higher throttle settings.

seedpws · #7 July 24th, 2007, 01:19 PM

No I had the plate all the way open. I haven't checked the compression. I will get that checked out. Also don't even know what the "link and sinc of the spark and the carbs" is. I got a shop service manual for it so I will look it up. Also should the high speed adjuster make much of a difference when moving it in and out? It doesn't now. Idles best when its all the way in - 1 turn out.

seedpws · #8 July 24th, 2007, 01:40 PM

"make sure you do not forget to place the round doughnut gasket on the emulsion tube at the botom in the carb center."

I see that alot. Something about it gets too much air if not installed. I had a gasket like was like the packing but was bigger. Does that go somewhere? Also I only put one packing and the plastic washer type thing in each high/low speed spots. Should there be more? Would either of these cause the problem? Thanks
Steve

F_R · #9 July 24th, 2007, 05:12 PM

There are supposed to be several (like two or three) packings on each needle. However, if they are holding the needle so it doesn't vibrate out ot adjustment, they are not your problem.

Also the 33 does not have nor does it need the gasket in the center. Reason: it has an adjustable high speed jet.

Normal opening for the high speed needle once adjusted is only around 1/2 turn. The 3/4-1 turn stuff is only to get it started till you can adjust it.

Just flat dieing at WOT sounds like bad fuel pump or sucking air somewhere between the pump and tank.

Lack of power sounds like it is running on one cylinder. Bad fuel pump is also one possible reason for running on one cylinder. But not the only reason by any means.

How much of this stuff have you checked out?

seedpws · #10 July 24th, 2007, 05:32 PM

Its not sucking air. I thought this might be the cause. I replaced all the fuel hoses.

I tested the spark using a spark tester. (one that goes on spark plug and other end into boot.) Is this good enough or how should that be tested. I was going to pull each boot off one at a time while running to see if there is a difference.

I took the fuel pump apart and cleaned the filter. It was all hard inside the fuel pump so I couldn't see if it was working or not. Not sure how to test it. If its the pump I would have to buy a whole new one as they don't sell rebuilds for it.

Heard it could be a faulty cut off switch grounding out one cylinder. I might remove it so I can see if that is the cause and repair/replace if so.

Also heard it could be coils. At higher rpm's they can jump. I also have new points ect I could install while I was in there. Not sure how to set them ect though. Also have to pull the flywheel and never had any luck doing that

What do you think it the most likely?

Thanks for all the help so far

seedpws · #11 July 25th, 2007, 12:26 PM

tashasdaddy · #12 July 25th, 2007, 12:35 PM

pull the plug wire and see if there is a difference. you can also put the tester in the circuit with the motor running to see if the spark is failing. yes, if it's the fuel pump replacement is better anyway. your on the right track. if you decide to pull the flywheel we can talk you thru that as well. i just recently did a 35 hp.

SuperMe · #13 July 25th, 2007, 02:06 PM

I think the most important questions aren't being asked here. #1 What does the engine do just before it dies? ie. rev up or bog down. #2 If you put your hand over the end of the carb and pull the engine over do you feel good suction? I think these are the things to look into before anyting else because they can tell you alot about what's going on.

seedpws · #14 July 27th, 2007, 10:22 AM

"What does the engine do just before it dies"

It revs up then shuts down 100%. I didn't have much power (couldn't plane the boat.) and then for a few seconds it revs up and almost planed it then shut down all at once. My father was standing up and he flew foward.

I haven't put my hand over it. Its been raining here a week so I haven't had a chance to check anything else out. What would cause low suction?

SuperMe · #15 July 27th, 2007, 01:31 PM

Since it revs up and then dies that means you aren't gitting enough fuel. That's your main problem. Fix it and you should be okay.

So, make sure that your fuel lines aren't plugged(even the part in the tank) if they are move on to making sure the fuel bowl fills nicely when you pump the primer. If this is okay then remove the filter from the fuel bowl. They commonly plug up. If it's the hard round type this is even more likely. Take it out and try your outboard. If this is your problem, I recomend putting a clear in-line filter in your line. That way you can see your fuel movement. Let me know if this helps.

seedpws · #16 July 30th, 2007, 09:45 AM

I might take the carb apart and see if the float is set correct. First time I ever did one and might not of set the float right. Is this something that could also cause it? Heard it could close too soon and on high speed its using more than it can supply. Is this correct? If not it must be the fuel pump as all the fuel lines are new.