RobbieBennett
Cadet
- Joined
- Apr 20, 2014
- Messages
- 6
I have a 1992 Playbuoy 20 ft. pontoon with a 1988 Mercury Classic 50 motor, model #B239037.
I have done lots of reading about issues with these motors but I can't seem to find a solution to my problem. I will start with the history of the motor, followed by what I have done so far and then problems I am having.
We bought the motor in mid 2013 after blowing up the original Evinrude 40. The guy who had the motor had replaced it with a 75 hp Mercury in late 2010 after about 4 years of use. He claimed the motor ran great but did not have enough power to take his 28 foot pontoon as fast as he liked. So in total the motor sat about 4 years from the time it came off his boat and went on mine. Even after I got the motor on last fall it took until this summer to start working on it.
Whats been done,
New spark plugs, May 2015.
New Battery, April 2015.
Carbs rebuilt, July 2015.
New water pump, February 2015.
New lower unit oil, 3 times so far.
New primer bulb, January 2015.
Fuel pump rebuild, September 2014.
New fuel filter, June 2015.
New fuel lines, 5/16 from filter to pump then 1/4 the rest of the way. June 2015.
Visually inspected wires over time.
Cleaned out gas tanks, checked pick ups and screens in tanks, August 2015.
New mid grade gas mixed 50:1 with Pennzoil marine oil with 8oz. of seafoam in each 6 gallon tank, August 2015.
__ Now it gets a little interesting __
New spark plug wires made from Chevy S-10 2.2 4cyl. wires.
New Mr. Gasket 4 to 6 psi electric fuel pump wired into the ignition switch.
New Mr. Gasket adjustable fuel pressure regulator, 0.5 to 5.5 psi. Both in June 2015.
The factory pump would not work before or after rebuild.
5/16 fuel line from tank to primer bulb to fuel filter. 1/4 fuel line from filter to pump to regulator to T to carbs.
Problems,
The electric choke (or whatever it is when you push the key in) does not work. No big deal because there is a manual choke on top the motor that does work.
Idles a little high in neutral.
Smokes quite a bit when in neutral with the throttle up. Not much smoke while in gear and moving.
When the motor is warm and been shut off with the key for more than 3 to 4 minutes it will only start back with the choke on, then the choke can be taken off and it is fine. If the key is turned off and then try to start within about 2 minutes it is fine.
Sometimes it dies at idle while in gear or low throttle in gear and the choke must be used to start back.
Sometimes there is a little gas on the water behind the motor after being shut off.
Now for the big one (at least in my mind).
From neutral to WOT it runs good and picks up speed for 15 to 20 seconds then either sputters until backed down to half throttle or so. Or it just idles itself to about half and smooths out. It will run just fine at half throttle for hours but tops out at 7 mph according to GPS.
I have no tach, just my ear. No overheat alarm and a good pee stream.
The above mentioned fuel pressure regulator seems to do best at 3 psi.
Also there is a rubber line that comes from a brass fitting on the head between the top 2 and bottom 2 spark plugs. It runs into the lower part of the cowl and is capped off.
I have tried to detail everything to the best of my knowledge. There seem to be several problems that lead me to believe a fuel problem. I am no marine mechanic but have spent plenty of time repairing ATV's and cars so I know a little. Hopefully someone knows what to do to get me going good before it gets cold again...
There are pictures of my boat, fuel system, plugs and a few other things (all taken 8-6-15) on my profile and it was last run 8-5-15 with all the problems happening at least once.
I have done lots of reading about issues with these motors but I can't seem to find a solution to my problem. I will start with the history of the motor, followed by what I have done so far and then problems I am having.
We bought the motor in mid 2013 after blowing up the original Evinrude 40. The guy who had the motor had replaced it with a 75 hp Mercury in late 2010 after about 4 years of use. He claimed the motor ran great but did not have enough power to take his 28 foot pontoon as fast as he liked. So in total the motor sat about 4 years from the time it came off his boat and went on mine. Even after I got the motor on last fall it took until this summer to start working on it.
Whats been done,
New spark plugs, May 2015.
New Battery, April 2015.
Carbs rebuilt, July 2015.
New water pump, February 2015.
New lower unit oil, 3 times so far.
New primer bulb, January 2015.
Fuel pump rebuild, September 2014.
New fuel filter, June 2015.
New fuel lines, 5/16 from filter to pump then 1/4 the rest of the way. June 2015.
Visually inspected wires over time.
Cleaned out gas tanks, checked pick ups and screens in tanks, August 2015.
New mid grade gas mixed 50:1 with Pennzoil marine oil with 8oz. of seafoam in each 6 gallon tank, August 2015.
__ Now it gets a little interesting __
New spark plug wires made from Chevy S-10 2.2 4cyl. wires.
New Mr. Gasket 4 to 6 psi electric fuel pump wired into the ignition switch.
New Mr. Gasket adjustable fuel pressure regulator, 0.5 to 5.5 psi. Both in June 2015.
The factory pump would not work before or after rebuild.
5/16 fuel line from tank to primer bulb to fuel filter. 1/4 fuel line from filter to pump to regulator to T to carbs.
Problems,
The electric choke (or whatever it is when you push the key in) does not work. No big deal because there is a manual choke on top the motor that does work.
Idles a little high in neutral.
Smokes quite a bit when in neutral with the throttle up. Not much smoke while in gear and moving.
When the motor is warm and been shut off with the key for more than 3 to 4 minutes it will only start back with the choke on, then the choke can be taken off and it is fine. If the key is turned off and then try to start within about 2 minutes it is fine.
Sometimes it dies at idle while in gear or low throttle in gear and the choke must be used to start back.
Sometimes there is a little gas on the water behind the motor after being shut off.
Now for the big one (at least in my mind).
From neutral to WOT it runs good and picks up speed for 15 to 20 seconds then either sputters until backed down to half throttle or so. Or it just idles itself to about half and smooths out. It will run just fine at half throttle for hours but tops out at 7 mph according to GPS.
I have no tach, just my ear. No overheat alarm and a good pee stream.
The above mentioned fuel pressure regulator seems to do best at 3 psi.
Also there is a rubber line that comes from a brass fitting on the head between the top 2 and bottom 2 spark plugs. It runs into the lower part of the cowl and is capped off.
I have tried to detail everything to the best of my knowledge. There seem to be several problems that lead me to believe a fuel problem. I am no marine mechanic but have spent plenty of time repairing ATV's and cars so I know a little. Hopefully someone knows what to do to get me going good before it gets cold again...
There are pictures of my boat, fuel system, plugs and a few other things (all taken 8-6-15) on my profile and it was last run 8-5-15 with all the problems happening at least once.