Sam Buckpitt
Recruit
- Joined
- Jul 17, 2012
- Messages
- 5
Hi i have a 1992 Four winns horizon 220. It has the big block 351 5.8L OMC engine. I bought this boat as a project. The owner previous to me didn't have the impeller installed. It over heated, then he immediately turned it off:facepalm:. That sucked lake water back through the engine and had water in the oil. Me and my mechanic took of the manifolds and heads. The heads along with the valves were fine. We basically did the top end and changed the oil. Before we re- did the heads some cylinders had 20-30lbs of compression. The previous owner later told us that he replaced the drive cable. We knew that could have caused problems with the switch that turns off the four cylinders to shift (forgot what the acronym for it is). Over all we are having trouble getting it to fire on all cylinders.We unplugged the swich and still fires weird. What it does is when we start it the boat runs really rough. when it runs you can hear that every few seconds all eight cylinders fire then it goes back to running rough. It seems like it has intermittent spark to a few of the cylinders. The main coil sparks correctly but I am wondering if it could be the distributor? Or low compression? (when the manifolds are on we cant get the gauge in the spark plug hole, thus, we cannot test the compression.) We tried new ignition cables but it didnt help any. We did replace the ignition switch, which kept it running but it didn't fix the problem we have now. Any suggestions?