'83 Johnson 35 "slipping" and "reving" in forward

[stugalvis]

After searching all of the posts that referred to "slipping out of gear," I decided that I could use some more help. I recently dug my grandfather's old 13' whaler out of the mud, redid the interior and paid a mechanic to get the 1983 Johnson Sea Horse Running. Unfortunately, the cooling system still wasn't working so I replaced the water pump and then the thermostat. The old thermostat was frozen full of sand and salt and completely wrecked. The first test drive after my repairs started off great and she ran well for the first push. After taking it out of gear for a minute and putting it back into forward, though, when I got the throttle 75% down it felt like it slipped out of gear, and revved out of control. She does great and has no problems until I get the throttle mostly down and just about get the boat onto plane, but then the prop stopps spinning (or so it feels as the boat slows drastically and eventually stops)and she revs out of control so I have to put her quickly into neutral. I'm a novice but very handy and learning fast... and I do have a manual. Thanks in advance to anyone who has any ideas or pointers.<br /><br />Stu.

 

[diggerdan17]

Re: '83 Johnson 35 "slipping" and "reving" in forward

have a 35 horse 1980 myself....it sounds like the clutch dog or maybe if you have remote controls it could be just the cable that needs adjusting.try adjusting the trunion nut on the end of the shift cable first.then if problem still exists drop the lower unit oil and see what that looks like.the clutch dog is in the lower unit and i recently i had the exact same problem it would be fine until i hit 3/4 throttle then it would jump out of gear and rev up way to high.do a search for clutch dogs and you will see many posts regarding this problem including mine.i installed new "dog" and she has worked good so far.

 

[tashasdaddy]

Re: '83 Johnson 35 "slipping" and "reving" in forward

it could be a misadjusted shift cable, spun prop, clutch dog. check them in theorder listed.

 

[stugalvis]

Re: '83 Johnson 35 "slipping" and "reving" in forward

Tashasdaddy, Thanks for the quick reply. I'll jump on it in the morning. If anyone else agrees, has any other ideas, etc... please let me know. I'll post back with some results.<br /><br />Thanks- Stu.

 

[stugalvis]

Re: '83 Johnson 35 "slipping" and "reving" in forward

Diggerdan, It always feels good hearing someone else that had the same problem. How bad is it to get into the clutch dog.

 

[ob]

Re: '83 Johnson 35 "slipping" and "reving" in forward

These gents have you headed in the right direction Stu.

 

[OBJ]

Re: '83 Johnson 35 "slipping" and "reving" in forward

Stu...if I'm reading the problem correctly, at about 3/4 throttle, the engine revs high and you lose forward thrust.....is that it?<br /><br />If so, this could also indicate a spun prop hub. Easy test....take a marker that won't wash off with water, draw a reference mark from the inner rubber hub to the outter shell the hub sets in. Run the engine to get the problem and check the reference mark. If the mark on the rubber protion of the hub is no longer in line with the shell, the hub is spun.

 

[BoatBuoy]

Re: '83 Johnson 35 "slipping" and "reving" in forward

Sounds more like spun prop hub. When clutch dog lets go, it's with a "wham", like hitting a log.

 

[diggerdan17]

Re: '83 Johnson 35 "slipping" and "reving" in forward

i,m sorry i mis understood the post....definately look for spun hub first...its the easy thing to do.

 

[stugalvis]

Re: '83 Johnson 35 "slipping" and "reving" in forward

Thanks all. I have been reading the manual for hours this morning worrying about how I'm going to get the two special tools to get to the dog. The slippage is very smooth and I do lose the forward thrust. I'll check that out first. Thanks for the catch OBJ and Boatbouy. Diggerdan, no worries, you replied quickly and made me feel good about posting to this site. I'll test today and re-post this evening.<br /><br />Thanks, Stu.

 

[stugalvis]

Re: '83 Johnson 35 "slipping" and "reving" in forward

Well, I hate to change the subject, but I guess I cant get to working on this problem until I get her started. There seems to be some sort of blockage or airlock in the fuel line somewhere and she won't start. The bulb and line from the tank are working because it "spits" a little stream of gas when I remove it from the engine and the bulb is tight. There is gas leaking from the thin hose below the fuel pump/filter at the 90' fitting when I try to prime the bulb, so there is pressure getting that far. I don't know what happens after that. I did just drive the boat from sea level in New Orleans up to Boulder, CO at 5300'. When I try to start it, it just spins continuously and never turns over. I had the same problem in Louisiana before I first got her started. A friend advised me to take out the plugs and run the key before putting the plugs back in and start on half choke. This worked every time, but that was the only way it would start. Finally after using this method in the river, she "coughed" (for lack of a better term) and then started right up from then on. Unfortunately, that technique is not working now. Any thoughts?

 

[OBJ]

Re: '83 Johnson 35 "slipping" and "reving" in forward

Stu....we need to determine wether it's fuel or spark.<br /><br />Can you do a spark test or have you done one? The spark should jump at least a 7/16" gap at each cylinder.<br /><br />Fuel....take a spray bottle with some premix in it. Before you start, give the carb throat a spray or two of the premix and then see if she starts. If it does start and keeps running, you have a fuel delivery problem or maybe just needs a carb overhaul. Do make sure there are no leaks between the supply and carb. Hoses are plyable and not hard.

 

[stugalvis]

Re: '83 Johnson 35 "slipping" and "reving" in forward

I have never done a spark test, nor do I currently know how to do one. She started in New Orleans after my spark plug removal/replacement proceedures. My guess was after hearing that "cough" that it was a fuel test. It also started on the first try every day for a week before we drove it back up. I'll try the spray bottle test, though since it's the only thing I have all of the tools to do, but the carb was replaced by a professional last July, so I would tend to think that it works better than anything else. don't you have to replace gaskets when doing a spark test? <br /><br />Thanks again, Stu

 

[stugalvis]

Re: '83 Johnson 35 "slipping" and "reving" in forward

Sorry, Sorry, Sorry! Please disregard starting issues. Next time I will ABSOLUTELY make sure that the kill switch is COMPLETELY depressed by the cap. I'm going to test the hub slippage now. Thanks, I will post back later. <br /><br />Feeling silly, Stu.

 

[OBJ]

Re: '83 Johnson 35 "slipping" and "reving" in forward

It's OK Stu, happens once in a while....that's the old original cap. Next time at the J/Rude dealer, get the new style. It has three fingers to keep the kill switch depressed.

 

[stugalvis]

Re: '83 Johnson 35 "slipping" and "reving" in forward

Alright Gents...you were right (hopefully),<br />It appears that I have a spun prop hub. I was able to re-create the problem out on the lake this afternoon and now the Sharpie line on the prop is about 120' off of the line on the shaft and the nut. Where do I find the hub by itself online and is it as easy to fix as it seems? Is there a better hub system available? Will I ever stop asking questions?..<br /><br />Ever so impressed, Stu.

 

[ob]

Re: '83 Johnson 35 "slipping" and "reving" in forward

You're doing good Stu.Unless you access to a hydraulic press and some drifts ,I'd just take to a reputable dealer or propshop and have a new hub installed.Course ,you might could save a few bucks and buy one beforehand.<br /><br />I had an 83 Rude once that had the safety lanyard rubber cap stretch out over time and grounded the ingnition intermittedly as you describe above.If you don't upgrade to the new style as OBJ eluded to,you might at least pick up a new cap of the same style that will seat tighter.That is,if yours 'is' stretched out and wasn't just unsnapped.

 

[tashasdaddy]

Re: '83 Johnson 35 "slipping" and "reving" in forward

stu, what is the condition of your prop itself. if nicked and dinged, while in prop shop they can do a total reconditioning.. it good money spent. also you might consider picking up a used prop with the same pitch on ebay, to have as a spare.

 

[stugalvis]

Re: '83 Johnson 35 "slipping" and "reving" in forward

The prop itself is in great shape... no nicks or dings. Is the best way to get a new hub just to get a new prop and do they come installed in the props? It sounds like y'all definitely recommend having a spare prop and hub... is that correct?<br /><br />Thanks again, Stu.

 

[tashasdaddy]

Re: '83 Johnson 35 "slipping" and "reving" in forward

i carry a spare prop on all my boats. as far as the hub in concerned it's not for the novice to replace. a spare prop will get you home if you happen to damage the one in use. of course nothing ever happens when is sunny, cool, calm water. it waits till all heck breaks loose. if you want to purchase a spare get the #'s off you prop and watch ebay.