Ugh. I need some smart people help. I spent the last 2 - 3 weekends trying to fix this engine and I think I'm getting close, but was incredibly disappointed today when I was able to get it in the water for the first time. Here's what I know:
2005 Merc 4.3 Carb'd, 0w324734
Cracked underside of original intake manifold resulting in milkshake (long story), replaced it.
Moved carb and thermostat over of course, new gaskets. New gaskets for intake manifold.
The throttle cable barrel thingy got moved some, but I think I got it close enough now.
Compression is between approximately 155 - 165 on all cylinders.
Temperature didn't climb above 170* at all today on the water while I was putzing around at 1500 rpm/10 mph.
Engine won't go over 1500 rpm without bogging/ lurching. It never got above 2000 rpm on muffs or in the water. I never pushed the throttle all the way down though, as I was uncomfortable doing so with how it felt up to that point.
Fuel was fresh at the end of last season, and had SeaFoam fuel stabilizer added to it during winterization process.
Crankcase and oil appears to now be nearly 100% free of water. I put a 20 weight oil in it before going out today, and drained it after returning. It's a little dark, but I don't see where it has separated from any water. This is the 3rd oil change now, as the first two were after idling on muffs.
The oil that came out is around 4.5 quarts, which I believe is right on the mark.
I removed the spark arrestor and it didn't change the performance. Bogged after 1500 rpm. I did notice a slight amount of smoke coming out of the left crankcase breather hose, but it really wasn't much.
Idle out of gear is around 1000 rpm. When I put it into gear and the boat starts moving forward, engine speed is around 800 or 900 rpm.
The engine has a deeper growl than I remember.
Exhaust manifolds were tested with Acetone, no leaks. New exhaust and riser gaskets, no leaks. Motor has < 100 hours on it, so I didn't replace the risers. Flappers look healthy. Boat has only seen salt twice, 2 years ago.
Spark arrestor/ air filter doesn't appear clogged anywhere.
I put the engine in base timing mode when I did it on muffs, and timed to 10* BTDC per spec. Did it again today on the water. When I reinstalled the distributor with the intake manifold, I verified #1 cylinder was at TDC and rotor was pointed @ #1 wire contact.
Propeller is intact and undamaged.
Spark plugs do not show signs of running rich or lean.
Removed throttle cable and manually tried to increase engine speed - no change.
That's all I can remember. I'll update this as I think of more things I did and checked.
Something I've been wondering about though - is it okay to increase the engine speed while using muffs? If so, that would really help as the water is 1.5 hours away :-(
2005 Merc 4.3 Carb'd, 0w324734
Cracked underside of original intake manifold resulting in milkshake (long story), replaced it.
Moved carb and thermostat over of course, new gaskets. New gaskets for intake manifold.
The throttle cable barrel thingy got moved some, but I think I got it close enough now.
Compression is between approximately 155 - 165 on all cylinders.
Temperature didn't climb above 170* at all today on the water while I was putzing around at 1500 rpm/10 mph.
Engine won't go over 1500 rpm without bogging/ lurching. It never got above 2000 rpm on muffs or in the water. I never pushed the throttle all the way down though, as I was uncomfortable doing so with how it felt up to that point.
Fuel was fresh at the end of last season, and had SeaFoam fuel stabilizer added to it during winterization process.
Crankcase and oil appears to now be nearly 100% free of water. I put a 20 weight oil in it before going out today, and drained it after returning. It's a little dark, but I don't see where it has separated from any water. This is the 3rd oil change now, as the first two were after idling on muffs.
The oil that came out is around 4.5 quarts, which I believe is right on the mark.
I removed the spark arrestor and it didn't change the performance. Bogged after 1500 rpm. I did notice a slight amount of smoke coming out of the left crankcase breather hose, but it really wasn't much.
Idle out of gear is around 1000 rpm. When I put it into gear and the boat starts moving forward, engine speed is around 800 or 900 rpm.
The engine has a deeper growl than I remember.
Exhaust manifolds were tested with Acetone, no leaks. New exhaust and riser gaskets, no leaks. Motor has < 100 hours on it, so I didn't replace the risers. Flappers look healthy. Boat has only seen salt twice, 2 years ago.
Spark arrestor/ air filter doesn't appear clogged anywhere.
I put the engine in base timing mode when I did it on muffs, and timed to 10* BTDC per spec. Did it again today on the water. When I reinstalled the distributor with the intake manifold, I verified #1 cylinder was at TDC and rotor was pointed @ #1 wire contact.
Propeller is intact and undamaged.
Spark plugs do not show signs of running rich or lean.
Removed throttle cable and manually tried to increase engine speed - no change.
That's all I can remember. I'll update this as I think of more things I did and checked.
Something I've been wondering about though - is it okay to increase the engine speed while using muffs? If so, that would really help as the water is 1.5 hours away :-(
