1994 Johnson 150 HP Ocean Runner

lundboat

Petty Officer 3rd Class
Joined
Dec 1, 2002
Messages
76
On a 1994 Lund 1850 Tyee.<br /><br />Last night the tach just stopped working. Where should I start troubleshooting this?<br /><br />Thanks.
 

Moving Target

Seaman
Joined
Apr 22, 2003
Messages
61
Re: 1994 Johnson 150 HP Ocean Runner

I would start with checking wires at the gauge. I would bet one broke off or something. Should not be to hard to find and fix.
 

lundboat

Petty Officer 3rd Class
Joined
Dec 1, 2002
Messages
76
Re: 1994 Johnson 150 HP Ocean Runner

Thanks. I'll give that a look.
 

Reelistic

Seaman Apprentice
Joined
Apr 1, 2003
Messages
30
Re: 1994 Johnson 150 HP Ocean Runner

If you fail to find any loose wires, I would check to make sure your battery is charging. The tach signal comes from the voltage rectifier/regulator. Easiest way to check the rect/reg is to connect a voltmeter across the battery terminals... voltage should be in the neighborhood of 12 volts. Start the motor and increase throttle... voltage should approach 14 volts. If the voltage remains at 12 volts or less, you may have a faulty regulator. Resistance checks of the stator windings will help confim.
 

DIRTPOORE96

Seaman
Joined
Jan 31, 2002
Messages
50
Re: 1994 Johnson 150 HP Ocean Runner

Hi Lundboat, I agree with the regulator/rectifier suggestion. Those rectifiers have 4 diodes inside of the case & if 1 diode burns out the charging system fails. Your alarms will also start acting up. Oil & fuel alarms will sound for no reason. Your tach stops working, motor runs rough & dies. You should check your battery voltage. Thats where I would start. Those rectifiers run about $190.00 dollars on the internet.
 

lundboat

Petty Officer 3rd Class
Joined
Dec 1, 2002
Messages
76
Re: 1994 Johnson 150 HP Ocean Runner

Hmmm... I'm not happy to hear the Voltage Regulator come up again. I just replaced it at the begining of the season. I've only had the boat out 3-4 times since getting it replaced. However, since getting it back the low oil warning horn has been sounding, even though there is plenty of oil and it is consuming the oil just fine.
 

Reelistic

Seaman Apprentice
Joined
Apr 1, 2003
Messages
30
Re: 1994 Johnson 150 HP Ocean Runner

If indeed you find your Rect/reg defective again... There was a post some time ago addressing repeat rect/reg failures. Repeat failures may be caused from overheating. The Rect/reg is located at the top of the block and is water cooled. If you get a vapor lock (steam traped in the top of the block) the rect/reg will overheat and die a horrible death!!! The post desribed a way to vent the block to prevent this problem. Try a search on rect/reg failure for your motor and see if you can locate the post.
 

Reelistic

Seaman Apprentice
Joined
Apr 1, 2003
Messages
30
Re: 1994 Johnson 150 HP Ocean Runner

Hey lundboat, the post you may want to read is titled "Johnson 200 Charging System" posted May 09, 2001. Lots of good info!!
 

lundboat

Petty Officer 3rd Class
Joined
Dec 1, 2002
Messages
76
Re: 1994 Johnson 150 HP Ocean Runner

Thanks All! I read that post and I'm willing to bet that that is what's happening with my engine, as I was doing the slow cruise (5mph) for about 2 hours in 90 degree heat before the Tach stopped. Fortunately, I'm burning up Regulators at such an impressive pace that it is still covered under warranty. I just got off the phone with the mechanic who put the last one in and the parts and labor are all still covered. I'll mention to him about putting in the vent that was suggested in the other post on the top of the block. Hopefully that will solve my problem. As this is getting me down.<br /><br />If my engine is indeed getting this air pocket in the top of the block, and getting a little too hot up there, is that going to cause the engine permenant damage?
 

lundboat

Petty Officer 3rd Class
Joined
Dec 1, 2002
Messages
76
Re: 1994 Johnson 150 HP Ocean Runner

I took my boat in this morning and I already have it back. The mechanic said the voltage regulator was the culprit, but it showed no signs of overheating. He said the regulator itself must have just been defective. All in all it only cost me about an hour of my time. Got to love a good warranty. <br /><br />Thank you everyone for the advice.
 

seahorse5

Rear Admiral
Joined
Jan 24, 2002
Messages
4,698
Re: 1994 Johnson 150 HP Ocean Runner

Lundboat,<br /><br />A common cause of regulator failure is wing nuts on the battery. For years Johnson and Evinrude state to use lockwashers and hex nuts tightened with a wrench, many "mechanics" don't. Any loose or intermittent connection will stress a regulator and eventually "blow" it.
 
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