Tail tell only pees while cranking. 86 Johnson 25hp

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juandi824

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Gainesville, fl
Hi guys as you can see, its my first post. Also my first boat. On the first day I was out on the lake the water pump ran dry and the engine turned off. And wouldn't start. Took it back to my place and started working on it the first thing is that it wasnt peeing water out the tail tell. So I replaced the water pump housing, impeller, gaskets. while cranking it it will pee, once it turns over and running the stream stops.. So I noticed that while the engine is cranking it spins a different way than when it's actually started is this normal? My guess it that the water pump only works while its turned one way(CLOCKWISE while cranking). Or when my engine starts the exhaust gasses block the water way through a bad head gasket. What do you all think..
Oh by the way when the lower unit is down and water hose is directly on the bottom of the water tube, I get a very nice stream.
Thanks for the help and I notice this water pump topic has been beaten to death.sorry,
 
juandi824 said:
So I noticed that while the engine is cranking it spins a different way than when it's actually started is this normal?
It's "tell tale" as in tell a story, and no. At least not on any motor I've ever seen. But let me be sure, you're saying that the motor turns one direction when you pull the starter rope or use the electric starter but when the motor fires and runs, it starts spinning the opposite direction?
 
Yup that's what I find very wierd . Looking down on the flywheel while hitting the starter, it spins clockwise, then when it starts it rotates CCW. And the "tell tale" only pees while its spinning clockwise.
 
juandi824 said:
Yup that's what I find very wierd . Looking down on the flywheel while hitting the starter, it spins clockwise, then when it starts it rotates CCW. And the "tell tale" only pees while its spinning clockwise.
Does the driveshaft change direction too? Because typically the impeller is installed around the driveshaft...
 
Honestly I'm not sure, i work in airplanes but I'm new to these outboard things.. It feels like the pump runs backwards because instead of pumping water out the tell tale it shows some bubbles in the water bucket like if it was pumping air down instead if up.
 
juandi824 said:
Honestly I'm not sure, i work in airplanes but I'm new to these outboard things.. It feels like the pump runs backwards because instead of pumping water out the tell tale it shows some bubbles in the water bucket like if it was pumping air down instead if up.

First, I would put the motor in a deep barrel of water over the shock mounts...

[youtube]https://www.youtube.com/watch?v=STC7bgueu10[/youtube]
 
The motor running backwards is usually caused by the ignition timing being way off or a bad power pack.
 
Check and replace the thermostat and carefully examine the small passages in and out of the thermostat for blockages. My 1975 25 hp Johnson did this and I found a piece of silicone sealant that had broken loose and blocking the intake passage to the thermostat.
 
Jasper thanks, but I've put the engine way down into the barrel.
Thanks guys for the replies, apparently my engine is running backwards, where do I start? To revers the darn thing..
I'm 100% that it is running counterclockwise.
Also noticed that if I remove the top spark plug cap it runs the same.. (A Lil rough I thought it was carb issue)
When I'm back at the shop ill do a compression test and thermostat R/R
 
MNHunter505 said:
Does the driveshaft change direction too? Because typically the impeller is installed around the driveshaft...
You have to be kidding on this reply......right?

Would consider pulling the flywheel and seeing if the flywheel key is sheared.
This would be the only way I know of that this can occur. In all my years I have never seen this but his description matches what would happen. We can do this on some antique engines while they are running by dropping the timing until the engine backfires then retard the timing handle even more to "advance" the timing in reverse rotation.
The engine must kick like a mule when the rotation reverses on a modern engine. Am surprised the starter gear or starter is still hanging in there.
 
Thanks all for the replys
JM.. Year make and model are on the subject field 1986 Johnson 25hp 2cyl 2stroke.
I'm away from the boat at the moment once I get my hands on it. I will check compression, Flywheel key, and timing..
Is 145ftlbs torque the right spec for the flywheel?(ref. online forum)
How do I go about. Timing check?

Somewhere else on the forum I read about a "trigger" can someone enlighten me please.
Also a known problem to engines running backwards.
 
juandi824 said:
Thanks all for the replys
JM.. Year make and model are on the subject field 1986 Johnson 25hp 2cyl 2stroke.

I appreciate the reply but it wasn't me that was looking for that info. :)

Pappy said:
Well, we have something around 9 replies without ever asking what kind of engine we are "working" on. Lets start there.
 
Yep....I missed that the first time around. Shoot me! :D
Have never known a "trigger" to do this on a Johnson/Evinrude product nor have I ever heard of it from any dealer over the last 35+ years.
Just for the heck of it I called another old Jo/Ev service rep I keep in touch with and asked him if the CD ignition is capable of running the engine in reverse. Neither he nor I know why it wouldn't. On some of the older pre-CD ignitions there was an anti-reverse spring that would shut down the ignition. Am still looking into this for my own knowledge.
 
Another update. Checked with a third Ex service rep who has made some sense of it. When the flywheel is turning in reverse on a CD ignition the charge coils and timer base will produce power in a reversed polarity. The reason being that the flywheel magnets are charged North and South in a particular order based on engine rotation. When the magnets pass the coils the polarity tells the coil to produce power in either + to - or - to + depending on rotation. The charge coils under the flywheel charge a capacitor in the pack and the timer base coils under the flywheel tell the SCR in the pack when to release this charge to the ignition coils to fire the spark plug. This reversed polarity will not be recognized by the SCRs in the power pack. Think of the SCR (silicon controlled rectifier) as a gate that holds voltage until the proper time to release it. Since they do not recognize the reversed polarity they will not open when the timer base signal hits them and release the 300+/- volts to the ignition coils which then ramps that up to around 30,000V available to the spark plug.
 
juandi824 said:
Also noticed that if I remove the top spark plug cap it runs the same.. (A Lil rough I thought it was carb issue)
So then its basically running on one cylinder and not pumping water? I agree with Pappy dont see anyway it could run backwards. I would check every water passage from the intake on up. Blow air thru it all. Make sure the water tube seals are good also.

Steve
 
I spoke to my tech, he said to change the magnetic pick under the the fly wheel. I order one @$26 ill probably change it this week end and let you all know.

Acwd, The engine is running backwards.
Pappy, where about central fl are you located. I'm in Orlando not sure of any good mechanics around.
 
Back in my motocross days, I had a Husqvarna that would occasionly "kick back" while kick starting and run backwards. 4 speeds in reverse. :lol: Timing was fine.
 

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