Spit, Pop and Burp. 97 200 Ocean Pro

[dingbat]

Thanks to all the good info I received from here I've worked through everything and got it to idle fairly but I have two remaining issues.

The first is that it "burps" now and then. What I mean is that it will instantaneously drop revs, burp a puff of smoke, and then jump right back up and idle normally until the next burp which seems to happen every minute or so. I assume its cylinder dropping out but have not been able to locate the offending cylinder using a spark tester. Are there any tricks I could try to narrow down the culprit?

The other issue is that when I dump the throttle the engine will wind right up but the #2 and #4 carbs spit a bit on the way up and I get a pop every once and a while from the #2 carb. The carbs have been rebuilt but I'm guessing that I still have something not quite right in those 2 carbs. Am I on the right trail?

 

[Joe Reeves]

Re: Spit and Pop and Burp. 97 200 Ocean Pro

Re: Spit and Pop and Burp. 97 200 Ocean Pro

Fuel being spit back out the carburetor throat would indicate that a reed plate (leaf/flapper valve) is not seating properly.

With the engine running (to check a carburetor), simply insert a couple fingers into the carburetor throat (acting as a manual choke) to richen the mixture.... but not enough to flood that cylinder.

If this eliminates the popping, puffing, etc, you've found the offending carburetor. If this is the case, check to see if the jets (size varies) are in their proper location and clean that carburetor, rebuilding it with a new kit.

 

[dingbat]

Re: Spit, Pop and Burp. 97 200 Ocean Pro

Thanks Joe.
I cleaned the carbs which resolved the spit and pop issue.
Now all I'm left with is the intermittent miss at idle which at times becomes an all out miss at elevated rpms. I assume that it’s a coil breaking down but is there a easy way to narrow down the offending cylinder/ cylinders? Pulling plug wires has yeilded minimal results

 

[Joe Reeves]

Re: Spit, Pop and Burp. 97 200 Ocean Pro

The affected cylinder should reveal a spark plug that is different in appearance from all the others.

Check the compression on all cylinders and look especially for water traces on the spark plugs which would indicate a failing head gasket or O Ring, whatever is used on your engine.

Check the coils for continuity as follows:

(Magneto Capacitance Discharge Coils)
(J. Reeves)

Check the continuity of the ignition coils. Remove the primary orange wire from whatever it's connected to. It may be connected to a powerpack screw type terminal, a rubber plug connector, or it may simply plug onto a small boss terminal of the coil itself.

Connect the black lead of a ohm meter to the spark plug boot terminal, then with the red ohm meter lead, touch the ground of the coil or the powerhead itself if the coil is still installed.

Then touch (still with the red lead) the orange wire if it's attached to the coil, or if it's not attached, touch the primary stud of the coil. You should get a reading on both touches (contacts). If not, check the spring terminal inside the rubber boots of the spark plug wire. Poor or no continuity of a coil is one reason for s/plug fouling.