WTB Johnson 115hp V4 Powerhead

[arnettjs]

All,
I've been told the powerhead on my 1992 Johnson V4 is bad. I'm not sure I am in agreement but need to gather resources to purchase a new one. Anyone EDIT know a reliable place to get one?

BTW, here are the symptoms. OB shuts down down after 3-5 minutes at WOT, like someone turned the key off. Will restart but run rough. VRO bypassed, new fuel solenoid, new voltage regulator (tach wasn't working, is now). Compression good in all four cyliders according to shop. Same shop is now saying that crank bearings in two cylinders are spun and carbs are flooding out as a result. I'm not in agreement, OB runs great and never misses until the shutdown. Another shop is looking at it now, says they think its electrical.

Thank you in advance,
Jeff

 

[Chris1956]

Re: WTB Johnson 115hp V4 Powerhead

Jeff, I do not agree that the powerhead is shot. In addition the bearings and carb issues are not related.

You need a new shop....

Your symptoms sound like a bad fuel pump. You might pump primer buld when running at full throttle. Also check the see if the motor is overheating. This would trigger the SLOW system which kills spark to 2 cylinders.

 

[Benny1963]

Re: WTB Johnson 115hp V4 Powerhead

thats funny spun main bearings ,
carbs and mains dont go together i hopr they didnt charge you for that diagnostic run a comp check sounds like there out to get ya

 

[Dhadley]

Re: WTB Johnson 115hp V4 Powerhead

Since the rod & main bearings are needle bearings I hope they're spinning. You'll only have a problem if they QUIT spinning.

Find a new shop that's familiar with outboards. Too bad we can't post names of places like that to help other hard working boat owners.

If you'll let us know where you're from maybe we can point you to some good shops.

 

[arnettjs]

Re: WTB Johnson 115hp V4 Powerhead

Greatly appreciate all responses so far.

In all fairness, I'm not sure what is wrong yet. I know one thing, the first shop didn't fix it. They did bypass the VRO, change the choke solenoid, and change the voltage regulator. $870 dollars later, I still have the same problem.

My boat is at a second shop now, getting a second opinion. The plugs I pulled looked like they were burning just fine. Pee spray from the water pump is very strong also. No alarms are sounding. I don't think I have the SLOW system on this year OB (1992 115hp Johnson V4). Second shop seems to think its electrical (power pack, ignition, etc.) w/o looking at it yet. They are going to diagnose it next week and let me know.

Ran fine on the hose, idled at 1100 RPM and seemed to get full throttle with no issue. Planing out at the lake, only gets to 37 MPH on the GPS, runs there for about 3 minutes, then shuts off. Overheating? Possible. Never getting full 5800 RPM or the 45-50 MPH it should get to (someone jump in here if I am wrong).

Its my first boat and I'm fairly frustrated. Not giving up though, no way.

Thanks again, I'll listen to ANYTHING at this point, fire away with any and all suggestions.

Respectfully,
Jeff

 

[SKEETR]

Re: WTB Johnson 115hp V4 Powerhead

Wiring at lanyard, neutral safety switch? Water in gas or clogged filter? So many ways to go.... I tend to lean towards the fuel pump theory.

 

[JB]

Re: WTB Johnson 115hp V4 Powerhead

I agree with the above comments and with the second shop.

Sounds like a high probability that you have a heat related ignition failure.

 

[tashasdaddy]

Re: WTB Johnson 115hp V4 Powerhead

i agree electrical heating up and failing, that is the immediate shut off, if it were fuel related i feel it would surge before dieing.

 

[arnettjs]

Re: WTB Johnson 115hp V4 Powerhead

Shop #1 didn't fix the problem but Shop #2 did. First and foremost, the powerhead is fine. Shop 2 found some gunk in the carbs, incorrect plugs (I'm serious), pulled the fuel pump apart and cleaned it, changed the fuel lines, and adjusted the linkage. Finally, Shop 2 found a leaking carb gasket that was askew and would saturate with fuel and 'bloat'. The end result? A test ride on the local lake with myself and the owner, 20 minutes worth or running perfect on plane. Also, it idles like a dream now. If you'd like to to know the name of this shop, please email me. I'm so happy to have my boat running again!

 

[iwombat]

Re: WTB Johnson 115hp V4 Powerhead

Greatly appreciate all responses so far.
Ran fine on the hose, idled at 1100 RPM and seemed to get full throttle with no issue. Planing out at the lake, only gets to 37 MPH on the GPS, runs there for about 3 minutes, then shuts off.

For future reference:

Don't ever rev up past about 2000 RPM on the muffs. It's a good way to toast a powerhead.

 

[arnettjs]

Re: WTB Johnson 115hp V4 Powerhead

Great piece of information, thanks!