1985 20hp Evinrude (Belgium) What type of sneeze or miss is this? Video inside

[flconrad]

Hello again,
Been working on this outboard for a while now. 110 comp on each cyl. New stator, trigger, coils, plugs, wires, rebuilt carb with new low speed needle and gasket, and fuel pump, rebuilt manual primer and replaced lines with oem ones. Only thing original on this is CDI. After all this, idles great, but at any throttle and starts coughing at mid range, smooths out at high. Pulled new plugs, very oily, but wiped right off clean. I have my manual and have done everything at specs, torqued right, etc. What is my next move? New CDI?

video: V1443_19-12-12_zps2d4accee.mp4 video by flconrad | Photobucket

 

[Joe Reeves]

Re: 1985 20hp Evinrude (Belgium) What type of sneeze or miss is this? Video inside

It sounds like you have the synchronization slightly off..... throttle butterfly starting to open too soon. The butterfly should just start to open (if memory serves me proper) when the scribe mark on the cam aligns dead center with the carburetor cam roller.

 

[flconrad]

Re: 1985 20hp Evinrude (Belgium) What type of sneeze or miss is this? Video inside

It sounds like you have the synchronization slightly off..... throttle butterfly starting to open too soon. The butterfly should just start to open (if memory serves me proper) when the scribe mark on the cam aligns dead center with the carburetor cam roller.

Thanks Joe, I do have that set correctly. Still doing the same thing. Strange thing though, it will smooth out if I put my hand over the carb lightly. Maybe there was some sort of breather on this carb originally? Using Ethenol free gas 89oct- 50:1 all new fuel lines, but it did not change the breather line that runs on the starboard side of the engine.

What do you think my next step is? I have had many outboards, this one has been crazy. Can't give up on it, got 400 in the lower unit alone...lol

 

[bpollock]

Re: 1985 20hp Evinrude (Belgium) What type of sneeze or miss is this? Video inside

running to lean will cause this,,

 

[Joe Reeves]

Re: 1985 20hp Evinrude (Belgium) What type of sneeze or miss is this? Video inside

Strange thing though, it will smooth out if I put my hand over the carb lightly.

Then, as "bpollock" has stated above, the carburetor is apparently set too lean..... or air is entering the crankcase via another route.

There is no "breather" on that model. What happens if you set the sync slightly off so that the throttle butterfly opens just a tad late?

I read that you checked compression (110 psi). With the spark plugs removed, have you checked the spark to see if it jumps a 7/16" gap with a strong blue flame on both cylinders (A real SNAP!)? The gap is important, checking spark by using the s/plugs is a waste of time.

As an afterthought..... when you mention running at idle, half throttle, full throttle, especially full throttle, you do have that engine on a boat, in the water and underway... or in a test tank with a test wheel on it don't you. It does make a difference.

 

[oldman570]

Re: 1985 20hp Evinrude (Belgium) What type of sneeze or miss is this? Video inside

Then, as "bpollock" has stated above, the carburetor is apparently set too lean..... or air is entering the crankcase via another route.

There is no "breather" on that model. What happens if you set the sync slightly off so that the throttle butterfly opens just a tad late?

I read that you checked compression (110 psi). With the spark plugs removed, have you checked the spark to see if it jumps a 7/16" gap with a strong blue flame on both cylinders (A real SNAP!)? The gap is important, checking spark by using the s/plugs is a waste of time.

As an afterthought..... when you mention running at idle, half throttle, full throttle, especially full throttle, you do have that engine on a boat, in the water and underway... or in a test tank with a test wheel on it don't you. It does make a difference.

Bump ^1 The carb has to be set with the motor in water so it will have backpressure on it to be done correctly. Seting the carb on muffs (as in the video) will only get it set to run ruffly. Motors on muffs should never be run at higher RPM's as damage can be done to the motor. Placing the motor in a barrel with the water 6" above the cav plate should get the carb set alot closer to real settings needed. JMO
Oldman570

 

[flconrad]

Re: 1985 20hp Evinrude (Belgium) What type of sneeze or miss is this? Video inside

Thanks Joe and oldman. I have spent the afternoon with the motor in a barrel, set the sync slightly off so that the butterfly opens a tad late. Running much better. Checked the spark with an automotive spark tester- #2 jumps hot and snappy, #1 not as strong. I could feel the #2 plug boot zapping between my fingers when I pulled it. ???? I have ordered another new coil, as the ones I installed were sold to me as good used. Going to swap coils and see if the weak spark follows. It may be a while before I get back on this, heading out of town again. Merry Christmas everyone!

 

[flconrad]

Re: 1985 20hp Evinrude (Belgium) What type of sneeze or miss is this? Video inside

Well, I'm back home a just spent a couple of hours trying to trace down this air leak. Also, now all the exhaust gasses are coming out of the 2 tell tales on the back of the leg and not thru the hub. This just started today. Found and corrected all ground issues, spark is great, motor starts by hardly touching the start button. It was still sneezing. Found that there were 2 exhaust cover screws missing from the cover. I bought this re-man head and never noticed !! Tomorrow I am going to pull the exhaust cover and check the jackets. It's pumping water good, just seems to be running a little too hot. Does anyone think the lean sneeze could have been all the time those 2 exhaust screws missing? I hope I can find them locally, otherwise I will have to wait for an order to come in to see if that cures it.

 

[oldman570]

Re: 1985 20hp Evinrude (Belgium) What type of sneeze or miss is this? Video inside

Tou should be able to buy the bolts at most good hardware stores. Make sure that the missing ones threads are good and that the old bolts are not broke off in the block casting. By removing one of the other bolts and taking it with you to get replacements would be best. They will need to be made of stainless as that is what the others should be. If you think that tere is air leak you can find it by using WD40 and spraying it around all the gaskets an crankshaft seals.If the fuel pump has not been rebuilt , it could be causing your lean condition also. Using a tempary clear fuel hose from the filter to the carb will let you see if there is a air leak in the fuel supply that needs fixed.JMO
Oldman570

 

[flconrad]

Re: 1985 20hp Evinrude (Belgium) What type of sneeze or miss is this? Video inside

Thanks oldman570 ! I have the bolts off the old head, so no problem there. The fuel pump is the new type triangle not square and I have just rebuilt it. I have a glass type see thru fuel filter inline before the pump. I do see bubbles in there. All fuel delivery is new, tank, hose, bulb,connections and fuel is non-ethenol. Bad weather right now, but I plan on removing the fuel filter thinking the pump can't draw hard enough for it. Update on progress soon. Thanks to All!

 

[oldman570]

Re: 1985 20hp Evinrude (Belgium) What type of sneeze or miss is this? Video inside

If you have air bubbles in comming into the fuel filter then there is a air leek from it back to the tank. Removing the filter from the hose might solve the trouble as the end gaskets on them are not very good at sealing. Putting the clear hose between the pump and carb works best. Not sure about your motor having a small balance line from the crankcase or from the intake cover on the side of the block to the carb. If there is a small hose from the carb going to one of those locations , you need to check it for cracks and leeks also. JMO
Oldman570

 

[flconrad]

Re: 1985 20hp Evinrude (Belgium) What type of sneeze or miss is this? Video inside

Thanks,, oldman570 again! Yes, I have the balance line. Came already on the reman block. Looked ok, never thought about it again. Will check. I will remove fuel filter for now and replace before the carb after I get this resolved. It will probably be 2-3 days before I can get to try all this and test in barrel. I will post update by end of week.

 

[flconrad]

Re: 1985 20hp Evinrude (Belgium) What type of sneeze or miss is this? Video inside

Ok, I got time today to work on it for a couple of hours. Everything we discussed above is either been done, replaced or ok. No air leaks that I can tell. Now, when it runs, it floods itself, runs too rich, and floods itself to a halt. I have taken the carb down twice with entirely new kits each time, float and all. I am beginning to think this is not even the right carb on this motor. It has 0398098 stamped on top. I had read somewhere in the forum that there was a parts dealer that let a guy try a different carb and then if it worked would charge him. I bought this motor like this and have never been able to get it to run right. Tried everything on this forum, secret files, carb adjust, everything is correct, spark, compression, etc. I had also heard on the forum, that the Belgium made motors had problems with the carbs? I would really like to try a different carb on this motor, but I am sure of what I should be looking for. 1985 20 hp BE20BFCOS. Since it is Belgium made, there are no reference part numbers for this motor on ********** or marineengine.com Where would I start to find a different carb?