bogs down at high speed

[fun123fun321]

I am in desperate need of professional help. Can someone please help me out. I have a 1993 Mariner 50hp. The motor would run at full throttle for awhile. sometimes 5mins, sometimes 30mins. then bogs down. When that happens. I would put it to idle and slowly throttle it. The motor would slowly move up to 1500 - 2000rpm, then start to bogg down again, but ocassionally it would recover and runs fine for awhile then boggs again. I removed the plugs and found them kinda wet. I replace them with new ones. Then it would run fine for a bit(1mins+). I've rebuilt the fuel pump, new gas tank and cable gas/oil mix ratio 1:50(quick silver prem), all three piston are firing. Could it be the carb,stator,plug wires? I have the manual, but no help. Your help is greatly appreciated.<br />Thanks in advance.

 

[dannymoe69]

Re: bogs down at high speed

try running some sea foam through it. If this makes any difference rebild the carbs

 

[Keith Buchanan]

Re: bogs down at high speed

After all that trouble I am wondering why you have not replaced the H.T. leads. You replaced the plugs at least and then did a fuel pump rebuild and even trashed your poor old gas tank. Thank God you have found the right site and welcome friend (Your profile didn't give your name).<br /><br />Get yourself a new set of leads. 90% Of problems of this sort are down to leads. You say that all off your plugs are firing but I bet that not all of your plug bottoms are the same colour. Please post back with your findings. Also a compression test may not be a bad idea..<br /><br />Regards Keith B..

 

[fun123fun321]

Re: bogs down at high speed

Thanks guys, I should of waited for a reply first.<br /> I took the Carb apart today and it looked very clean, sprayed carb cleaner through all the holes/jets. No clogs found. what a waste of time. <br />I just ordered new leads and coils online. I will<br />post updates. Thanks Again.<br />-John

 

[fun123fun321]

Re: bogs down at high speed

One other thing I forgot to mention. It revs up fine in neutral after it bogs. Why is that?<br />Thanks

 

[fun123fun321]

Re: bogs down at high speed

I just replaced the leads. The found lots of clay like gunk in the coils, where the leads connect. I think the previous owner put the wrong crap in it. Took the boat out last weekend and the boat ran great. Taking it out again this weekend. hopefully it will be fine. <br />Thanks for all your help<br />-John