87 Johnson GT150 on 18' Ranger not building RPM's under load

Its a 87 GT150. When in neutral it revs and builds RPM's but when in gear it will not. I get a friend to get on the front deck to plane out and then it will maybe build and get me to 25 mph. I pulled the plugs to see what is going on and pound them fouled by oil. Some gaps were even closed from oil. It seems that the VRO is puumping to much oil. I'm going to disconnect the oil injection hear before the season starts. I like the idea of peace of mind. Does anyone think that this is whats causing that. The powerpacks, plugs, and coils have been replaced to no avail. Any suggestions much appreciated.

Re: 87 Johnson GT150 on 18' Ranger not building RPM's under load

2 plugs the oil intake line on oil injection pump and to tank plug both line's disconect the oil pump electic wiring make sure you have 50-1 oil in gas first 1 pint for each 6 gallon's of gas make sure it's got gas to all carb's like it not running on bottom two carb's this is just test run see if it's getting two much oil if it run's fine you know it in oil injection system mine i run 100-1 in gas too i seen them quit and lean out and blow up motor,burn up ring's, not oil fool plug's the marine place has by pass kit for wiring and new pump for gas run mixed too but wiring disconect my 1991 omc 150xp book has pic's off it to buy pass pump to i set up websight if needed <br /> http://photobucket.com/albums/f325/gatorer/omc-stuff/xp150/?action=view&current=36feb915.jpg <br /><br /> http://photobucket.com/albums/f325/gatorer/omc-stuff/xp150/?action=view&current=24c61896.jpg <br /><br /> http://photobucket.com/albums/f325/gatorer/omc-stuff/xp150/?action=view&current=21d9495f.jpg <br /><br /> http://photobucket.com/albums/f325/gatorer/omc-stuff/xp150/?action=view&current=scan0002.jpg <br /><br /> http://photobucket.com/albums/f325/gatorer/omc-stuff/xp150/?action=view&current=scan0003.jpg <br /><br /> http://photobucket.com/albums/f325/gatorer/omc-stuff/xp150/?action=view&current=scan0004.jpg <br /><br /> http://photobucket.com/albums/f325/gatorer/omc-stuff/xp150/?action=view&current=scan0005.jpg <br /><br /> http://photobucket.com/albums/f325/gatorer/omc-stuff/xp150/?action=view&current=scan0006.jpg <br /><br />this is my section on oil injection of repair book the gas is raw with oil injection put oil in gas if by passed

Re: 87 Johnson GT150 on 18' Ranger not building RPM's under load

It would appear that you are not firing on all cylinders. <br /><br />I would run a compression test , then check spark, then decarb. <br /><br />Lots of people have taken motors to pre-mix and have been happy. It's a little more work, but it is certainly reliable.<br /><br />Also, you are probably aware that the mixing pump you have will most likely work as a fuel only pump as well.

Re: 87 Johnson GT150 on 18' Ranger not building RPM's under load

well the thing that gets me is when in neutral it runs fine, builds RPM's no problem, hence replacing ignition. Other than the VRO it would be the other thing that changes when the load changes. It doesnt foul them unless it is in gear. I guess I'll see what happens when I bypass the oil side. I was just wondering if anyone knew of anything else to check. If the bottom 2 or any of the carbs was not getting gas then it wouldnt even run right in neutral, correct? I'll see what happens and hope for the best. Regardless I don't trust those pumps so its going to do fuel only.

Re: 87 Johnson GT150 on 18' Ranger not building RPM's under load

In neutral your motor can run on half it's cylinders, reach high RPM, and throw a rod. <br /><br />You should do the tests, for sure.

Re: 87 Johnson GT150 on 18' Ranger not building RPM's under load

Do as "ezeke" suggests and don't assume anything. Remove the spark plugs, rig a spark tester whereas you can set a 7/16" gap. Crank the engine. The spark shoul;d jump that gap with a strong blue lightning like flame.... a real SNAP! does it?<br /><br />Check the compression which should be 100+ psi and even on all cylinders. Is it?<br /><br />In essence.... Trouble shooting starts with the basics.<br /><br />In neutral, a V6 engine with three cylinders missing will turn up a generous amount of rpms as there is no load on the engine. It is, in a manner of words, free wheeling. However, turning high rpms in neutral is not a good idea as you can encounter a runaway engine scenario whereas connecting rods will be flying out the side of the powerhead before you csn figure out what to do about it.

Re: 87 Johnson GT150 on 18' Ranger not building RPM's under load

Put a new set of proper plugs in and run it,plus do what everybody said.Take the carbs.apart and clean them .Leave the oil pump on.I dont see why too much oil is a problem.On mine,my fear is not enough oil.