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How is this possible

T

tp2gam

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Runs like a striped ass ape on muffs but won't accelerate above 1200 rpm in the lake. Have checked compression, spark, float level, vacuum leaks. It is a 1988 merc black max 200 2 stroke. I am in big bear altitude is about 6500' already have high altitude jets prop is a 19 pitch, fuel lines and tanks are new. Please help. Sorry the video won't upload but it runs great on the muffs. It spits and sputters then dies on acceleration above 1200 but will plow around for as long as you like and restart perfectly 1200 or below.
 
You have basically posted a link to the hard drive of your Windows computer. There is no way any can, (or should), be allowed access to your HDD.
make your video into a YouTube, then post the link. Or, move your current video to a hosting site, then post that link.
 
Edchris177 said:
You have basically posted a link to the hard drive of your Windows computer. There is no way any can, (or should), be allowed access to your HDD.
make your video into a YouTube, then post the link. Or, move your current video to a hosting site, then post that link.
Click to expand...
Thanks
 
Sorry all for my computer illiteracy but the video is now available on youtube labeled as 1988 merc black max 200 I know you should not run in gear at high rpms on the muffs but getting desperate
 
Copy the link, then paste it here. People don’t want to search a zillion YouTube boat videos , to find what may, or may not be your motor.
 
Sounds like ignition issues. You need to do a compression test and get a $10 spark gap tester from your local auto parts store. Make sure your spark can jump at least a 3/8" gap. It will make perfect sense once you have the tester in hand. On muffs, there's no resistance to the exhaust. Low compression or inadequate spark will show up when there is resistance to exhaust flow.
 
Here, I fixed it for you.
motors in neutral or running on muffs will run very well even with a dead cylinder( s), first steps are compression check,(with a reliable gauge), & a spark test, with a spark tester, either home made, (free- just Google it), or purchase one.
Looking for spark by grounding a connected sparkplug is not sufficient.
I would strongly advise against revving the hell out of an engine with no load on it.
You may see parts flying out the sides, or, in Elon Musk terms, rapid unscheduled disassembly.
 
Thanks for the input I have picked up the gap tester and will check both the spark gap and compression on my next trip up. Will let you know what I find.
 
Oldsaltydog said:
Sounds like ignition issues. You need to do a compression test and get a $10 spark gap tester from your local auto parts store. Make sure your spark can jump at least a 3/8" gap. It will make perfect sense once you have the tester in hand. On muffs, there's no resistance to the exhaust. Low compression or inadequate spark will show up when there is resistance to exhaust flow.
Click to expand...
Can I do something like put steel wool in the center of the prop to create resistance on the muffs ??
 
It’s not simply a bit of exhaust resistance…the prop in the water is a great deal more. There are no shortcuts, or miracles in a can. The problem needs to chased in a logical, least cost method.
however, hope springs eternal, if you want to fill the prop with steel wool, go for it.
 
Edchris177 said:
It’s not simply a bit of exhaust resistance…the prop in the water is a great deal more. There are no shortcuts, or miracles in a can. The problem needs to chased in a logical, least cost method.
however, hope springs eternal, if you want to fill the prop with steel wool, go for it.
Click to expand...
Makes perfect sense just such a pain to haul and launch every time I make a change or repair to test. Guess that's just the nature of the beast.
 
The entire point of doing the first two tests is you will discover, or eliminate quite a few things without having to trailer & launch your boat. Those are always the first two steps to take.
 
Oldsaltydog said:
Sounds like ignition issues. You need to do a compression test and get a $10 spark gap tester from your local auto parts store. Make sure your spark can jump at least a 3/8" gap. It will make perfect sense once you have the tester in hand. On muffs, there's no resistance to the exhaust. Low compression or inadequate spark will show up when there is resistance to exhaust flow.
Click to expand...
OK here are the results as I just made it up on the mountain today. cyl #2 106 comp, 1/4" + spark gap. cyl # 4 106 comp, 1/4"+ spark gap. cyl #6 106 comp, 1/4"+ spark gap. cyl #1 106 comp, 1/4"+ spark gap, cyl #3 109 comp, 1/4"+ spark gap and cyl #5 106 comp, 1/4"+ spark gap. Any input would be greatly appreciated
 
Edchris177 said:
The entire point of doing the first two tests is you will discover, or eliminate quite a few things without having to trailer & launch your boat. Those are always the first two steps to take.
Click to expand...
OK here are the results as I just made it up on the mountain today. cyl #2 106 comp, 1/4" + spark gap. cyl # 4 106 comp, 1/4"+ spark gap. cyl #6 106 comp, 1/4"+ spark gap. cyl #1 106 comp, 1/4"+ spark gap, cyl #3 109 comp, 1/4"+ spark gap and cyl #5 106 comp, 1/4"+ spark gap. What do you suggest next before I tow and launch ??
 
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