1985 Johnson 150hp - Won't throttle up in the water.Update

[AlanR]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Your compression is a little to low for a 150 in my opinion

 

[emdsapmgr]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Normal (stock) compression should be in the 95# range.

 

[firemann2003]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

OK, checked fuel/VRO pump. Process = (on muffs)Gauge on outlet side of pump before manifold that goes to carbs. Pumped bulb to 10 psi. Started engine ran WOT. Is that process correct? If so here are the results = gauge dropped to 0 and stayed there, pumped primer bulb again and gauge went right back down. Is it possible for pump to be putting out no pressure and still able to go to WOT? No tach. right now so I don't know what the RPMs where doing.

 

[ezeke]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

You should never run your motor up on muffs. It can very easily run away and blow the engine up.

Please describe your technique for checking the compression.

You may want to print out the flowchart for testing the VRO pump. Copy the following to your browser without the quotation marks:
"http://www.maxrules.com/graphics/vropics/VROflowchart.JPG"

 

[firemann2003]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Compression check = (followed from manual) Purchased new compression check kit. Warmed up engine to operating temp. Removed all spark plugs. Installed gauge and cranked engine 5 or six times. Repeated in all 6 cylinders.

 

[ezeke]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Was your gauge the type that screws in?

 

[firemann2003]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Yes, it screwed in

 

[farginicehole]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Aren't you supposed to do the compression check with the throttle lever on the WOT position? My 150 is an '89 XP (E150STLCEM), and I can't remember for sure but I'll check my factory manual.

 

[ezeke]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

It is good to push the warm up lever up to open the throttle plates, but it won't make a lot of difference in the readings.

I think you have a motor with a lot of wear - Time for new rings.

 

[firemann2003]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Sorry forgot to mention throttle was open too. Think I am just going to rebuild it and call it good.

 

[farginicehole]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

For what it's worth, I did look in my manual and it does say to do the test with the throttle lever in the WOT position.

 

[firemann2003]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

I want to thank everyone for being so helpful with this problem. I think I have multiple issues and am going ahead with rebuilding the thing. It will be my first 2-cycle rebuild endeavor, so I am sure I will be back with more questions, LOL.

 

[firemann2003]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Hello again all, just an update for you. Finally this engine is showing some promise. Replaced VRO pump and now I can get to 2000 rpms, in the water, before it starts to choke out and die. Purrs like a kitten up until 2000.

 

[firemann2003]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

In neutral it will throttle up to about 5400 rpm. In gear it still chokes out at 2000. Any new ideas?

 

[firemann2003]

Re: 1985 Johnson 150hp - Won't throttle up in the water.

Re: 1985 Johnson 150hp - Won't throttle up in the water.

A couple other symptoms have popped up while wring tach and volt meter, don't know if they are related or not. Tach jumps around and sporatically works and the volt meter shows a low charge. Could these three symptoms be showing that the stator is bad?

 

[clint]

1985 Johnson 150hp - Won't throttle up in the water.Update

Check all your your coil connections that they arent crossed. Sounds like they could be since you arent getting over 2500 rpms. It wont necessarily backfire either. Did the mechanic at the shop disasemble any coils wiring? Anyway check out simple solutions that can make this run at low rpm's.
Clint 8)

 

[firemann2003]

Re: 1985 Johnson 150hp - Won't throttle up in the water.Update

Coils wiring is all correct. Weird thing is the one time I got to run this engine it ran great, second trip got the big nothing, lol.

 

[emdsapmgr]

Re: 1985 Johnson 150hp - Won't throttle up in the water.Update

The tach and low battery voltage are related. Probably a bad rectifier. The rectifier charges the battery and also counts pulses for the tach. If the tach reads funny, you will probably have a dead battery soon. Replace the rectifier.

 

[firemann2003]

Re: 1985 Johnson 150hp - Won't throttle up in the water.Update

Checked voltage coming to the battery with voltmeter, between 12 and 13 volts while motor is running.

 

[firemann2003]

Re: 1985 Johnson 150hp - Won't throttle up in the water.Update

As of now: Carbs. rebuilt, all new fuel lines, new fuel tanks, new primer bulb, fuel filter and VRO pump.

Parts on the way: Rings, Leaf valves, coils, power packs and plug wires.

Have another question, if I replace the rectifier/regulator should I go ahead and replace the stator, or vice versa? Will one being bad burn out the other?