Troubleshooting 1999 Johnson 225 HO

[ct1762@gmail.com]

Just a quick update -

Over the winter I spoke to a few knowledgeable boat guys and the first thing all of them mentioned was the prop hub.

Boat came with a Raker 14.5 x 24p. I sourced a Piranha prop 14.5 x 23p for cheap, will be launching the boat next week for the first time this season. Let's see how she goes.

Also did the impeller/water pump kit. Original housing was badly grooved, impeller was stiff but not too bad.

Also noticed that the spark plugs were not the recommended ones (QL77JC4). Replaced with the recommended (QL78YC). Does anyone think the plugs could have been part of my problem?

a bad hub = slippage= alot more RPM than 2k at WOT! This will do nothing in my opinion. Disconnect the tan temp sensor at the pack on both sides and retest. Just be 110% sure its not overheating. If the motor now gets up to full power, its the pack most likely. The only way to know for sure is to run through a complete ignition check via service manual steps and a DVA adapter. Really simple stuff. The temp sender and overheat alarm are directly related to SLOW in the pack as if its hot enough (205f or so) to send the pack into SLOW, its hot enough to set off the steady alarm. 3 beeps as menioned is a fuel restriction. check tank pickup, fuel filter, hose connections w. soapy water under pressure. In my experience a bad fuel pump would cause the motor to stumble the second you give it throttle, not at high RPM.

 

[WuTang84]

a bad hub = slippage= alot more RPM than 2k at WOT! This will do nothing in my opinion. Disconnect the tan temp sensor at the pack on both sides and retest. Just be 110% sure its not overheating. If the motor now gets up to full power, its the pack most likely. The only way to know for sure is to run through a complete ignition check via service manual steps and a DVA adapter. Really simple stuff. The temp sender and overheat alarm are directly related to SLOW in the pack as if its hot enough (205f or so) to send the pack into SLOW, its hot enough to set off the steady alarm. 3 beeps as menioned is a fuel restriction. check tank pickup, fuel filter, hose connections w. soapy water under pressure. In my experience a bad fuel pump would cause the motor to stumble the second you give it throttle, not at high RPM.

I'll be launching the boat for the first time this year on Friday. Gonna disconnect the temp sensor and give it a shot. I'll have my bro-in-law at the motor with a temp gun to verify we're not overheating.

By "pack" are you referring to the power pack? If so, that was one of the things the previous owner had replaced before he put it up for sale.

Do you think it would be worth it to head up there prepared with new fuel line and start replacing if need be? Or is this most likely not a fuel issue?

Also, I'm gonna have to verify which alarm is tripping. I'm almost certain it was a constant beep... but I'm gonna have to give it another shot as my memory is foggy.

 

[WuTang84]

A little update -

Put the boat on the water again, no more overheat warning since putting in the new impeller.
Disconnecting the temp sensors made no difference power-wise.

Still no power, not enough to plane.

Starboard cylinders are not running. Pulled the plugs and motor still ran the same as it was. Port side plugs, the motor would bog and die almost immediately.

Could some sort of fuel-side problem cause a cylinder bank to shut down?
Motor kind of seems like it's starving for fuel.

 

[racerone]

Is there spark on all 6 leads , yes or no ??

 

[WuTang84]

Is there spark on all 6 leads , yes or no ??

I'm guessing yes as the mechanic that did the work before I bought it diagnosed one of the problems as "no spark on some cylinders". He apparently fixed the spark issue though. I will check spark this week when I get back to the boat.

 

[WuTang84]

Okay, so... I have good spark on starboard side, all 3, nice and blue, jumping the gap no problem. Port side I have no spark on the middle plug (#4?), the other 2 are perfect.

Plugs are a little black, except for the port side middle, that one looks brand new.

Pulling the spark plug leads off didn't reproduce the same affects as it did on the water last week, but you can hear the misfire with port side top and bottom leads off.



Checked the coil packs with a multimeter set to ohms - they all check out at around 00.5

False reading on #4? I'm gonna go ahead and swap it
anyway.