Black spark plugs

[Bullred]

1E 002827 Okay, my motor has been idling poorly, so I was told it was probably the tracker or the fuel diaphragm so I replaced both well now the motor dies when you touch the peadal it will idle but not turn any RPMs. So I get it home an pull the plugs an they look like I painted them with black primer. So I pulled the diaphragms to check them an they look good still an they were seated correctly. Thoughts please Thanks

[JOE54]

need fuel/air psi test preformed after engine is shut off

[Bullred]

[QUOTE=JOE54;12913525]need fuel/air psi test preformed after engine is shut off[/
Okay we’ll just take a guess at what could be going on here. The motor would at least run before I swapped the regulator an tracker valve. Now it won’t even pull off the trailer.

[lmoore]

All due respect, “taking a guess” caused you to spend a couple hundred dollars on something that didn’t fix your issue. Taking some time to perform the basic tests is almost always better than the shotgun approach.

[Bullred]

All due respect, “taking a guess” caused you to spend a couple hundred dollars on something that didn’t fix your issue. Taking some time to perform the basic tests is almost always better than the shotgun approach.

I was told by a certified tech who had done a pressure test on the motor that it was a fuel regulator diaphragm I replaced the tracker a fuel. The ones I took out looked just fine I even put them under a cut out Gatorade bottle cap an put soap a water in the bottle a put the pieces under some pressure they both had no issues. I did a test today of my own an the pressures are 92# on air side an 106# plus or minus a # when I shut off motor the pressure holds an then they both drop at about the same rate. The fuel is the last one to completely drop to zero.

[DewRonInc]

Heck might be what was wrong with mine

[DewRonInc]

Or fuel pump rubber sleeve like joe said

[Bullred]

Or fuel pump rubber sleeve like joe said

I haven’t been told that yet, I hope it is that simple for you. ( if that is simple)

[DewRonInc]

Mine was crank trigger, urs is more likely fuel pump sleeve as far as a guess, but look at crank trigger and see if a screw is out

[Bullred]

It maybe! How does a sleeve affect the running issue I’m having?
an what purpose does it serve in the overall functioning of the motor?

[JOE54]

sleeve splits will have little to no fuel psi for just seconds may start die start die , BULL id have to see what all the sensors and switches are saying before i made a decision on whats causing plug problem /poor idle , does engine have new OEM stats in it 130
degree

[EuropeanAM]

It maybe! How does a sleeve affect the running issue I’m having?
an what purpose does it serve in the overall functioning of the motor?

Get those air and fuel pressure tests:

-At idle

-Under Acceleration

-5/10/15 seconds after engine shutdown (restart for each time period).

In 99+% of cases with a split fuel pump sleeve, you WILL see it in the results of the above tests.

Curious- when were your spark plugs last replaced?

[Bullred]

Get those air and fuel pressure tests:

-At idle

-Under Acceleration

-5/10/15 seconds after engine shutdown (restart for each time period).

In 99+% of cases with a split fuel pump sleeve, you WILL see it in the results of the above tests.

Curious- when were your spark plugs last replaced?

plugs were replaced 10 hrs or so ago if that. When I’m on the water I put in close to where I won’t to fish for the day an I fish more than I ride.
Pressure @ idle was. 92# port side an 106# on starboard side, I never idle engine up at all.
At shutdown pressure’s remained steady for 5 seconds or so then they started drop simultaneously an slow

[DewRonInc]

All you have to do is snatch top of VST off

[Bullred]

sleeve splits will have little to no fuel psi for just seconds may start die start die , BULL id have to see what all the sensors and switches are saying before i made a decision on whats causing plug problem /poor idle , does engine have new OEM stats in it 130
degree

Yes sir he said he replaced those. I’m gonna get a thermo temp tester an check the temp on each one. Could the motor have gone into guardian mode an blacked out the plugs while I idled 1/2 mile? What’s the procedure to get it out of guardian mode on the muffs? I can‘t idle it up much it throws a hi rev alarm!

[JOE54]

did you idle with warning horn sounding , dont rev it on hose or in neutral can damage gearcase , BULL has thid engine ever ran correctly, how long have you owned it ??? i know there are some very shady folks out there selling engines that are not up to par some of these i know for a fact that have ended up being sold to some good folks on this site with a rash of problems that myself and DON are trying to help resolve issues with , from what they have described to me are lets say very lack luster

[Bullred]

Well I could have rev’ed it up a little bit not high at all 1500 maybe the alarm would go off then stop when i eased off foot. Three times maybe! Too answer the running right question it has never idled right but it would run good when once you give it throttle an if I ran it fairly hard it would idle good once I come back down to idle it would idle good for 30 seconds or so then back to rough idle. The rebuilder has a pretty good reputation for doing a good job on these motors. But he told me he really didn’t know how to trouble shot the motor so he had a Mercury tech mechanic put it on the DDT an he said it was a fuel diaphragm issue. I changed that a the tracker an that’s when the plugs turned black. But let me say the motor had developed a skip in it the that I could hear an feel when I was coming in that afternoon an it didn’t won’t too run at all so something really happened then. I did replace a coil on it because it was skipping just like I just described an I pulled the plugs to find out which one of those was acting up.

[JOE54]

if problem with plugs started when you repaired rails i would investigate that system

[Bullred]

if problem with plugs started when you repaired rails i would investigate that system

This may or may not be an issue but the plug that’s on top of the port side rail blew off when I had the fuel line keeper off so I could fix the leak I had on the fuel line. Would there have been anything under that cap that could have blew out of the rail? It blew off as I turned away to shut engine down. I was very lucky to find the dag’um plug. I look at the rail parts diagram an I did not see anything under the plug on the drawing.

[EuropeanAM]

No- the plug simply has an o-ring on it. You're mighty lucky though... that puppy makes one heck of a slug, and had it connected with you....