76 Johnson Stinger 75hp In water Issues

[guswis76]

I have a 1976 johnson Stinger 75hp. When hooked up to a water hose runs great full power. But when i go to the lake it putts along. Pull motor out of lake idels back up put down putts again. I took it to a repair place they replaced the thermostat and tweaked it a lil But still no joy. Any Ideas????? Please help new boater thankyou

 

[billy4hp]

Re: 76 Johnson Stinger 75hp In water Issues

I have a 1976 johnson Stinger 75hp. When hooked up to a water hose runs great full power. But when i go to the lake it putts along. Pull motor out of lake idels back up put down putts again. I took it to a repair place they replaced the thermostat and tweaked it a lil But still no joy. Any Ideas????? Please help new boater thankyou

How do you know it has full power when it's on a hose? There is no load on the prop?? Its very common for outboards to idle at a lower speed when in the water compared to "on the hose" as there is significant pressure from the water on the exhaust outlet.

Have the basics been checked? Compression test, Good spark plugs, Cleaned out carbs, Decarb the engine if it has not been done for awhile, Fresh fuel? You may want to take a peek at the top secret files at the top of this forum as well as how to wake a sleeping motor great tips located there...

IMHO it sounds like the repair place either missed something or does not know what they are looking at...

I bet you either have dirty carbs and / or are dropping cylinder(s) under a load, you now have the choice of taking on the repairs yourself (get a good OEM service manual) or finding a reputable shop that wants to repair an older engine (which many don't want to mess with)....


Good luck,

 

[SS140]

Re: 76 Johnson Stinger 75hp In water Issues

Personally, Ive decided to take matters into my own hands and fix my outboard myself. Its not that hard and these guys on the forum know what they are talking about. Just search the forum for previous posts.

Some guys dont like the SELOC manuals. Some do. I dont have a manual as of yet, but I havent had any problems figure out a part or taking somthing apart and putting it back together. It's all pretty basic. There are A LOT of things I don't know, but I guarantee you I will before it's said and done.

 

[CaptnTony]

Re: 76 Johnson Stinger 75hp In water Issues

So, how'd the repair go? I'm looking at purchasing a 76 Johnson Stinger 75hp this week. It's suppose to run 'good', but the starter is out.

I don't know anything about fixing outboards (or many other motors). but over the last year I've gotten into a four wheeler, 3 jetskis, 3 snowmobiles and two new outboards.

Just trying to figure out how difficult getting into the cylinders and stuff is and whether you found a good manual for repair use (good pictures, some I've seen have awful black and white - more black than white - photos).

 

[jtexas]

Re: 76 Johnson Stinger 75hp In water Issues

That's one troubleshooting approach, randomly throwing parts at it till it starts working. That can get expensive. Another approach would be to rule out the possibilities, one at a time, then just fix what's broke.

I'd stay away from that parts-changer masquerading as a mechanic. Highly recommend the factory shop shop manual, it'll pay for itself many times over.

Does the fuel line hold pressure? Is the tank vent open and clear? Is the fuel fresh, and free from water and debris? Take billy4hp's advice...compression test, spark test and if those check out ok, rebuild the carbs.

BTW, it's best to avoid revving the motor when the lower unit is not submerged...without backpressure on the exhaust, thermal runaway is a possibility, with catastrophic results. Read about it here: http://forums.iboats.com/showthread.php?t=336014