Name:	cobra -	Reply
Subject:	Help on compression 50 hp 2 cycle year 2000
Date:	7/3/2014 12:55:13 AM

Catboat has been great help to me and I need to ask him one more question. I installed a new Mercury OEM power head on my pontoon about 6 months ago. The engine has done great until about a month ago. It would go dead when at idle. Wide open it never misses any.  It will tac at around 5000 and run perfect. This engine has only a few hours on it. Today I took my automotive compression tester to see what the numbers were. I was a little surprised to find all three cylinders were dead on 95 PSI. Is this enough compression for this new engine Cat ? I remember when I first bought this boat with original engine I checked with same tester and I think all three cylinders showed like 125 psi. Is this newer engine lower compression or has something happened to my engine?  I did notice lots of oil when I removed the cover. I also found a clear line connected to engine block near the starter on one end and not connected to anything on the other. Thats where it looks like the oil is coming from but not sure. I cannot find where to connect the other end. This is a green colored clear line about 1/8 size, looks like a fuel line on line trimmer. It could be a tad larger also as I was only guessing. The engine will idle real slow for about a minute and then die out. It cranks right back up and like I mentioned it runs great at 5000 rpm's. I did install the 10 degree four blade prop you suggested and it works perfect. Now again I am worried about the 95 pounds of compression. Like I said all three are exactly 95 testing with my auto gauge. I need to find where the line connects to. The engine has been dumping way to much oil in lake when running at low speeds and the bottom cowl is oil soaked pretty good. I have been still mixing a small amout of oil with every tank even though this engine is oil injected. I wanted to be on the safe side but now not sure if I was to safe. ?? HELP. The engine also smells rich when at idle. I rebuilt all three carbs when I installed the power head along with new plugs. The bottom plug tooked oil fouled today so I just put three new ones in. Any tips on what I got going on. I also heard a noise when I would rev it up to say 1500 rpm and then let off. Sound like it coming from deep in engine. Tom

Name:	Shortbus -	Reply
Subject:	Help on compression 50 hp 2 cycle year 2000
Date:	7/3/2014 7:42:51 AM

If that is your oil injection line from the injection pump to the engine I'd think thrice about running the engine until it is fixed...............

Look for the injection pump.  The oil tank may have tubing of the same type going to the pump.

Clean it up, spend time looking for the pump.  If you can't find it, idle the engine while looking for new oil spill after clean up.

I'll betcha the end of your mystery tube goes to the injection pump.

Your mileage may vary.

Name:	CAT BOAT -	Reply
Subject:	Help on compression 50 hp 2 cycle year 2000
Date:	7/3/2014 8:53:26 AM

I'd find the source of the oil leak first!  Then worry about the compression of the engine.  95 may be OK, not sure and would have to look it up.  Maybe it is time for you to make a road trip to the shop. 

Steve

Name:	Ulysses E. McGill -	Reply
Subject:	Help on compression 50 hp 2 cycle year 2000
Date:	7/3/2014 5:29:24 PM

Thats what I was thinking.....seems it would have been a lot easier in the first place and give the problems and time involved,  less expensive.