Suzuki 75 horse Sudden Power Loss

a1parrothead

Cadet
Joined
Sep 5, 2004
Messages
18
Hello everybody. I am new to the forum and hope you can help! Here goes. I have a 1990 Suzuki 75 horse. It is a 3 cylinder. Yesterday I had it on the water and it was running great. Then, all of the sudden a total loss of power. I was able to "work the throttle" and get it to speed again for a few seconds, but after that it was only going a little above idle speed at full throttle (It does not have a tach, so I cannot tell you the RPM's). When I throttle down it idles good and it still starts good. I did not overheat and had a good steady flow of water throughout the whole thing. I stopped and put in 3 new plugs I had on board. It did not help. I Limped it home at full throttle (very slow and low RPM's)with good water circulation. I tried pumping the primer bulb. It felt normal and did not help. Now it gets even stranger. When I got home I pulled out the 3 new plugs I had put in. #1 and #2 looked as if they had fired and now looked used, not new. But #3 sill looked shiny and new, just wet with fuel. That is to say it looked as if it had not been firing. So I thought # 3 was not working. I started the engine and pulled the wire off #3 plug. It did not seem to make a difference in how the engine sounded. A few minutes later I switched around the plugs from one cylinder to the other. Then I pulled them off one by one. This time you could here the difference each time a wire was pulled off, as if all cylinders were firing. Then I checked compression as best I could as I have not got a gauge (I will). It SEEMED like all cylinders had compression. Question #1- What should the compression be on this engine? And what amount of difference is acceptable betwwen cylinders?<br />Next, I checked the fuel line, fuel filter. They were fine. Then I pulled the fuel pump and tore it down. I could see nothing wrong. Reassembled and checked spark, all had spark but was not sure of a good way to see if it was adequete.It seemed kind of weaker then it should though. Not a strong blue spark, but more of a small yellow spark. This whole time it still ran the same. MAJOR loss of power even at full throttle. I am stumped. I have read about Power Pack problems, but honestly do not even know where or what that is! I am thinking fuel pump??? Any help you can give me would be great. I know SOMEONE can figures this out!
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: Suzuki 75 horse Sudden Power Loss

Howdy, A1PH.<br /><br />Welcome to iboats. :) <br /><br />You are not going to get a lot of helpers to read a 500 word paragraph that rambles.<br /><br />Do not duplicate your post in incorrect forums. I have deleted all but one and given you a link to read on the one I left.<br /><br />Read that link, then use the "edit post" icon to edit your post to a more concise explanation of your problem and what you have done so far.<br /><br />For starters, your engine is only running on one or two cylinders. you either have a gummed up carb or a bad ignition system.<br /><br />Good luck. :)
 

jim dozier

Lieutenant Commander
Joined
Jan 8, 2003
Messages
1,970
Re: Suzuki 75 horse Sudden Power Loss

Go to an auto parts store and buy a spark tester. Check your spark on all three cylinders. The Suzuki should be able to jump a good 1/2 inch or so.<br /><br />If you have spark pull off the airbox cover and squirt premix into the carb of the cylinder that wasn't working and see if it picks up. If so you have a fuel problem and will need to do the carbs. <br /><br />While you're at it replace the diaphragm in the fuel pump.
 

BrettL

Cadet
Joined
Jun 19, 2004
Messages
25
Re: Suzuki 75 horse Sudden Power Loss

The Compression at most shouldnt be off by 10% to any cylinder. I had this motor and had the same problem, never figured out quite what it was. Be VERY careful spraying into this motor! Do NOT use starting fluid, it will ruin the motor! Just spray gasoline right down the throat of the carbs. On this motor you cant really tell a difference at idle pulling any plug, although, there is a change in the exhaust note. Doesnt sound like it is the carbs, although, it could be. Make sure your gas tanks are clean and the gas is good, that seemed to help out my dt 75. Good luck!
 
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