Johnson 150 Fast Strike rev limiting @2500 (video link!)! please help!! UPDATED!!!

BigBassin78

Seaman
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Aug 13, 2011
Messages
64
Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

i did not disconnect it but just to test for the alarm. I hooked it back up, and when I ran the motor it went into slow mode immediately. Neither of the temp switches were making the alarm sound. I disconnected both one at a time and alarm continued to sound. Anyway, I am still trying to figure out why it is going into SLOW. I am hoping that when I resolve the VRO sensor thing that this will also fix the SLOW thing.

BTW according to my SELOC, SLOW stands for Speed Limiting Operation Warning.

PS: this is something I learned yesterday that I want to share in case this happens to someone else. Once I got the new starter on and the motor running I could not get it to idle, it would only continue to run with the throttle advanced. After about 2 minutes of this, trying to get the motor to idle, I went over the motor and noticed that there was a copious amount of oil sprayed out of the exhaust in a 12 foot streak and dripping from the prop. I thought this was bad, so, remembering that I had turned the little red lever from where it was and could not remember its original position, I thought I should look into this first. So, I turned it to 6 oclock position and it returned to normal operation and idled just fine. But again would not go passed 2500 rpm... Saga continues..lol
 
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clanton

Rear Admiral
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Jul 9, 2001
Messages
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Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

With all sensors disconnected, turn key on, horn should beep one time. Is it doing this????
 

BigBassin78

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Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

yes
 

clanton

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Messages
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Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Four sets of sensors for this engine, overheat only sensors that will set S.L.O.W. UNLESS the DIODE in the engine harness is bad. The diode blocks the VRO, Oil tank, and fuel restriction sensors from setting S.L.O.W . Sound like the horn is working OK. I would disconnect the 2 tan wires from the temp sensors and try it. If engine runs ok one or both of the temp sensors are bad. If engine still will not run, tan wires in engine and control harnes may be shorted to ground.
 

BigBassin78

Seaman
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Messages
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Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Ok, I have tested both temp switches. When I have the key on without the engine running, and ground both tan leads that connect to the temp swithes, the alarm sounds. I know that doesnt confirm that they ground at the correct temperature, but it works for now. Anyway, the motor is still going into slow mode and it is doing so immediately which also tells me that it is not the temp switches. Some has mentioned that it may be the powerpack all together, has anyone else heard of or seen this happen.
 

boobie

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Nov 5, 2009
Messages
20,826
Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

I've seen the powerpack doing this. But as mentioned above, it could also be the diode in the wiring harness.
 

BigBassin78

Seaman
Joined
Aug 13, 2011
Messages
64
Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

i see that the diode is buried in the harness just passed the main Red terminal connection. So I guess I have to cut into the harness to get to it. What value would I be looking for when testing this diode?
 

SparkieBoat

Captain
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Aug 17, 2009
Messages
3,643
Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

I am not sure what all test you have done...but am I correct to assume that it is going into SLOW mode with both temp wires and the VRO wires all disconnected?? if so, you may have a bad power pack...when it is in SLOW mode, what cylinders have fire and which ones do not??? a inductive tach light will tell you this.
 

laderwell

Cadet
Joined
Feb 20, 2010
Messages
26
Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

I am not sure what all test you have done...but am I correct to assume that it is going into SLOW mode with both temp wires and the VRO wires all disconnected?? if so, you may have a bad power pack...when it is in SLOW mode, what cylinders have fire and which ones do not??? a inductive tach light will tell you this.

I had that problem on my 175, i immediately hooked up my 6 gallon tank and the problem went away.

It turned out to be my tank pick up tube and clogged anti syphon valve did you also change out your filter on the motor if you have one and water seperator ?
 
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BigBassin78

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Messages
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Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

that being a fuel restriction issue, I assume you also got a horn sound?
 

laderwell

Cadet
Joined
Feb 20, 2010
Messages
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Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Most the times I did, but it was when I was going continuosly above 3000 RPM'S after running awhile . I bought a 6 gallon
portable tank which the alarm would not go off. I eliminated the possibility of overheating with a infared thermometer

I then hooked up a vacuum gage and watched it increase up to 7HG when the constant alarm went off, after replacing filter, anti syphon valve
it started doing the same thing without alarm on take off . I took out the anti syphon valve again and crap was blocking the ball
I had lots of crap in the tank causing the problem.
 

BigBassin78

Seaman
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Aug 13, 2011
Messages
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Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

I will check into the possibility of a fuel restriction but I doubt that that is the issue, thanks!
 

BigBassin78

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Messages
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Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Well folks, for those of you whom suggested the blocking diode, you were RIGHT! So, after all the "I told ya so's" I did end up replacing the power pack first, which is ***** backwards, I know. Im only 26 and on my second boat. Im learning. So to help others out there to learn from my experience here are some pictures.
f199b865.jpg

febc769b.jpg

50b60a92.jpg

These two bolts gave me some trouble. It took some needle nose pliers to get to them, thankfully they were not bolted down too hard.
4e14e70d.jpg

93a404f8.jpg

1ad712cf.jpg
 

daselbee

Commander
Joined
Jan 20, 2009
Messages
2,765
Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Well, I hate to burst your bubble, but I doubt the diode was the problem.

Here is why: All these sensors work on the principle that when they trigger due to a fault, they short to ground. The temp sensor, for example, when overheated, will trip internally, and cause the tan wire to go to ground. The pack sees that fault, goes into SLOW mode, and additionally, the horn sounds.

The diode is a blocking diode. It prevents the pack from seeing the ground condition on the OTHER sensors (no oil, low oil, and fuel restriction). It isolates the temp alarm from the others.

So here it is.....what better way to isolate any circuit than with a completely OPEN circuit like the BROKEN diode that your picture shows?
The only way the diode could cause your SLOW mode condition is if it was SHORTED, and therefore not isolating the other alarm conditions. (I am going under the assumption that the lead was broken, and you did not CUT it).

I suspect the pack was the culprit all along.

Clanton? What do you think?
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,589
Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

You should have ordered the pack kit as you still have the old wires., the OMC update was to the grey wires and reroute of the starboard temp wire as idf to close to spark plug lead it would trigger slow...hummmmmm. Make sure you have the Champion QL87YC plugs,grey wires,tan or red intake gaskets,sender reroute and you will be good to go.. Also the information is printed on back of pack.
 

BigBassin78

Seaman
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Aug 13, 2011
Messages
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Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Fazt, good advice, Ill look into those things, I have ordered the grey wires already, and I sould reroute the ground right?!

Daselbee, I understand your point of view assuming the diode was broken. However, the only circuit that can send the power pack into slow mode is the overheat (temp switches). The other tan leads in the circuit do not send enough voltage, hence the diode(gate). The diode is a gate that lets so much voltage across it, as well as, keeping the current flowing in one direction, not important in Direct Current though. Its purpose in this circuit is as you said to block lower voltage. I tested the current in both directions(full continuity in both directions) and that is how I diagnosed the bad diode. Once I clipped the diode(simulating the block) it ran just fine. So, all is well.
 

daselbee

Commander
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Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Daselbee, I understand your point of view assuming the diode was broken. However, the only circuit that can send the power pack into slow mode is the overheat (temp switches). The other tan leads in the circuit do not send enough voltage, hence the diode(gate). The diode is a gate that lets so much voltage across it, as well as, keeping the current flowing in one direction, not important in Direct Current though. Its purpose in this circuit is as you said to block lower voltage. I tested the current in both directions(full continuity in both directions) and that is how I diagnosed the bad diode. Once I clipped the diode(simulating the block) it ran just fine. So, all is well.


Ya know, others read these posts, and that one above was SO full of errors...so full of errors.

I am glad you have it running, but your analysis as stated above is just wrong.

Just so everyone else knows.....

Tan leads send NO VOLTAGE. The pack and/or warning horn DETECTS a ground condition on these lines when it occurs. Period.
Diodes are all about Direct Current. When a diode is present, it is in a DC circuit, OR it is in the process of converting AC to DC.
If you had current flow in both directions on that diode, it is shorted. It would have been nice to know you clipped it too.

Happy boating.
 

BigBassin78

Seaman
Joined
Aug 13, 2011
Messages
64
Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Thank you for your correction, I am still learning the electronics portion. I really should just keep my thoughts to myself until I know what I am talking about...Anyway, I have soldered what I believe to be an equivalent diode since I will not pay $15 for a half cent piece of silicone and tin. Daselbee, is this ok to put in its place? GP15M Silicon Rectifier Diode it shares the same main specs, 1.5A 1000v.
 

BigBassin78

Seaman
Joined
Aug 13, 2011
Messages
64
Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Ya know, others read these posts, and that one above was SO full of errors...so full of errors.

I am glad you have it running, but your analysis as stated above is just wrong.

Just so everyone else knows.....

Tan leads send NO VOLTAGE. The pack and/or warning horn DETECTS a ground condition on these lines when it occurs. Period.
Diodes are all about Direct Current. When a diode is present, it is in a DC circuit, OR it is in the process of converting AC to DC.
If you had current flow in both directions on that diode, it is shorted. It would have been nice to know you clipped it too.

Happy boating.

Just to clarify for my own education. How does the diode just detect a ground. ANY ground would send 12v+- to the diode, right, whether its the oil or the temp. So how would the diode be able to cut off current from one ground signal and not the other? I guess, is the signal voltage lower, say 3.3, from the oil and fuel pump, and the temp much higher, like close to 12v??
 

bob johnson

Rear Admiral
Joined
Feb 25, 2009
Messages
4,304
Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

Re: Johnson 150 Fast Strike rev limiting @3000 (video link!)! New boat please help!!

the OP has a fast strike version of the 150 hp johnson 60 degree looper motor. The OP states his model number is j150eleo. I had thought that the fast strikes were the the GL versions.....ie j150 gleo

does anyone know the different between the model numbers?

thanks

bob
 
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