My 1st post.
Got 1996 Force 120 HP and it runs great.
On muffs under 1/8 throttle (max RPM I'm willing to push on muffs), all spark plugs have the same. re: Black Oil Wet look but all plugs are the same color. Was told this is normal of lower RPM muffs. Did cold engine compression test and top 1 - 135, 2 - 132, 3 - 148, 4 - 152. All above 125 PSI and all within 15% variance (from top to lower number). On muffs, its responsive, starts easy, has water out its pee hole, etc, etc. On the lake, with cold engine, it intially starts easy and it runs smooth as well. After warm up on the lake, there isn't too much smoke (using 50:1 mix) and no misses at upper RPMs either. Runs great on the lake.
On the lake and after warm up, I turn key off. Try to restart 20 - 30 minutes later and it lugs as its cranks. Lugs like one cylinder sudden has too much compression. Pulled top 3 plugs and they are same color. Black / wet - like before on cold engine. Removed bottom plug and to my surprise, its clear - like a brand new plug was just installed. I don't see any white milk or clear water. But, its defiantly a "shinny new" color.
After searching, I get the feeling its exhaust manifold gasket is blown (or cracked). Thus, letting some water into lower piston chamber (especially at quick sudden stops) but not enough to hydro lock the piston. The more I read about clear lower spark plug color in bottom plug, the more I need to remove its exhaust manifold plate (cover), and do visual inspection.
Before I start this inspection job, what gaskets do I need? I read 2 x gaskets are needed, but for 1996 what part numbers (from iboats.com online store) do I need to buy? If doing this task, what other gaskets should I buy? For example, should I also re-do the head gasket or only do the exhaust gasket first, then new head gasket (if lower plug continues to be different color than other plugs)?
thanks.
Got 1996 Force 120 HP and it runs great.
On muffs under 1/8 throttle (max RPM I'm willing to push on muffs), all spark plugs have the same. re: Black Oil Wet look but all plugs are the same color. Was told this is normal of lower RPM muffs. Did cold engine compression test and top 1 - 135, 2 - 132, 3 - 148, 4 - 152. All above 125 PSI and all within 15% variance (from top to lower number). On muffs, its responsive, starts easy, has water out its pee hole, etc, etc. On the lake, with cold engine, it intially starts easy and it runs smooth as well. After warm up on the lake, there isn't too much smoke (using 50:1 mix) and no misses at upper RPMs either. Runs great on the lake.
On the lake and after warm up, I turn key off. Try to restart 20 - 30 minutes later and it lugs as its cranks. Lugs like one cylinder sudden has too much compression. Pulled top 3 plugs and they are same color. Black / wet - like before on cold engine. Removed bottom plug and to my surprise, its clear - like a brand new plug was just installed. I don't see any white milk or clear water. But, its defiantly a "shinny new" color.
After searching, I get the feeling its exhaust manifold gasket is blown (or cracked). Thus, letting some water into lower piston chamber (especially at quick sudden stops) but not enough to hydro lock the piston. The more I read about clear lower spark plug color in bottom plug, the more I need to remove its exhaust manifold plate (cover), and do visual inspection.
Before I start this inspection job, what gaskets do I need? I read 2 x gaskets are needed, but for 1996 what part numbers (from iboats.com online store) do I need to buy? If doing this task, what other gaskets should I buy? For example, should I also re-do the head gasket or only do the exhaust gasket first, then new head gasket (if lower plug continues to be different color than other plugs)?
thanks.
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