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help needed with 60hp mercury

J

judge

Member
Hi need help with my early 90s 60hp mercury outboard took it out on the weekend an left the boat ramp an it was running fine at about 1/4 throttle when i went to give it more 1/2 evern full throttle it just would go it just had no power ive put a new stator after the stator was done it sheared the key way got that fixed then i had the carbies done just before i took it out can someone pls help me
 
Start with a compression test, followed with an open air gap spark test, A nice lightning blue snap! follow that up with fuel diagnostics
 
judge, fuel diagnostics is troubleshooting the fuel system, you said had carbs. done what was actually done to them? Were they diassembled,soaked overnight,throughly cleaned,all of the jets gone threw, every passageway cleared with dry compressed air, reassembled with new gaskets,needle&seat,float adjusted,etc.
 
johnnygjr said:
judge, fuel diagnostics is troubleshooting the fuel system, you said had carbs. done what was actually done to them? Were they diassembled,soaked overnight,throughly cleaned,all of the jets gone threw, every passageway cleared with dry compressed air, reassembled with new gaskets,needle&seat,float adjusted,etc.
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I had the carbies cleaned an rebuilt everything was done on them ive changed fuel tanks fittings lines all new i just cant seem to figure it out
 
How's the spark? An open air gap test is the only way to test for spark, grounding plug do block tells you nothing. Next time on water,try pumping primer bulb when your issue arises, If this helps you have a fuel restriction or possible faulty fuel pump.
 
johnnygjr said:
How's the spark? An open air gap test is the only way to test for spark, grounding plug do block tells you nothing. Next time on water,try pumping primer bulb when your issue arises, If this helps you have a fuel restriction or possible faulty fuel pump.
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Spark is good , should the primer bulb stay hard all the time while its runing cause it aint an i checked the plugs the top cylinder looks ok but the bottom two are as black as the ace of spades
 
When you say good compression and spark what we hear is you have not done a proper compression test or a spark gap test. If you cannot give us numbers anything we say means nothing. What is the serial number?
 
As for the compression test was done when i had the carbies done an the said it had good compression an as for the spark i had it runing an pulled the leads of 9ne at a time an it was strong spark i held it about 10mm away an it was a descent spark ive just done the startor on it cause it had weak spark an serial num og024067 im going to by a compression tester an ill get back to u with the out come
 
judge said:
As for the compression test was done when i had the carbies done an the said it had good compression an as for the spark i had it runing an pulled the leads of 9ne at a time an it was strong spark i held it about 10mm away an it was a descent spark ive just done the startor on it cause it had weak spark an serial num og024067 im going to by a compression tester an ill get back to u with the out come
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Ok compression test is 120 on all cylinders changed fuel tanks to new ones new fuel line connectors it runs fine out of water revs 5 to 6000rpm out of water took it to the water under load with the throttle wide open it will only rev between 2600rpm to maybe 3000rpm at full throttle an suggestions pls this is really starting to get the better of me
 
Reving in nuetral means nothing to me.------It will do that running on 2 of 3 cylinders.---------Sounds like you have a dead cylinder.-----------Start it up at the ramp and pull one plug lead of at a time.---------Is there the same response on all 3 ??
 
Once engine is running, The primer bulb should remain semi firm, fells like it's half full,not as hard as before starting. Bottom plugs,sooty and black,insufficient spark,incorrectly gapped plugs,bad coils, plug wires and/or compression issue, Keep us posted, Run the compression test 3 times 1-3,1-3,1-3,all plugs removed,with a fully charged battery,
 
Never take a two stroke past high idle without a load on the prop. It takes alot less fuel to rev up. It is like running a engine without oil in it you will damage the pistons and cylinder walls. The spark must jump a open air gap of at least 7/16 inch brite blue snap on all the plug wires. Have you adjusted the engine sync between throttle opening and spark advance? With the engine off in forward gear put the throttle to wide open then look in the carbs the throttle butterflys should be fully open.
 
I had the same issue, turned out my trigger was faulty. If u have a timing light check each plug wire at fast idle for a short period and see which one cuts out..

Is the idle nice and spluttery /chunky? That's a good sign. Spent months trying to diagnose mine! Let me know if you need any help, think I'm quite familiar with these now!
 
Also, make sure ur fuel bulb, fittings, pump is working and delivering enough fuel, and filter is clean.

Plugs need to be good. Check compression too. Basics first. I had one tank that leaked air and fuel starvation occurred..
 
Also, make sure ur fuel bulb, fittings, pump is working and delivering enough fuel, and filter is clean.

Plugs need to be good. Check compression too. Basics first. I had one tank that leaked air and fuel starvation occurred..
 
FstaRockr Burns said:
Also, make sure ur fuel bulb, fittings, pump is working and delivering enough fuel, and filter is clean.

Plugs need to be good. Check compression too. Basics first. I had one tank that leaked air and fuel starvation occurred..
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I just cant work out wat it is i took it back to the mechanic that done the cardies he put the boat in hes water tank it runs fine revs to 6000rpm no problem he says theres nothink wrong with it take it out to tbe water it wont run past 2500 rpm it
 
Sounds like the carb idle adjustments are set too lean. Try a 1/2 turn out on each screw. That has cured many a problem like this.

Jeff
 
Kinna sounds like your stuck in the hole. Have you tried different trim angles, is the hull clean, possible double bottom full of water, how do you distribute weight in the boat all can keep it from hitting a proper plane.
 
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