Evinrude Yachtwin 9.9 Help

[wolfbaysailor]

I recently purchased the above referenced long shaft motor for my Hunter 25. It starts and seems to run pretty well, but I am not getting near the thrust I had hoped for. I am certain there is a problem with the motor, but my diagnostic skills are lacking. The boat does make headway, but just barely. It wouldn't take much in the way of wind/waves on the bow to stop it dead and probably start it in the other direction.

The model number is E10SELCDB and I believe it is either a 1985 or 1986 model. 2-stroke...

Some symptoms that may or may not be related....

1. There is, what I believe, an excessive amount of white smoke that is constantly coming from the exhaust. It's not thick like you would see from an auto with bad rings, but it is there.

2. Shifter does not consistently work. Sometimes I can not get it to go into reverse.

3. I get a good stream of water when the engine is running, but I am also seeing water leaking around the bottom of the engine housing, where the shaft passes through the housing.

I am searching this forum for more information, but thought I would get this post out there as well. There is a lot of useful information here. Especially, for a first time outboard owner.

Thanks,
Jeff

 

[Xcusme]

Re: Evinrude Yachtwin 9.9 Help

Gees, where to start....oh yea..

Welcome to iboats.

You'd be well advised to find a factory service manual for your motor for starters. Since this is a new to you motor, I'd take compression readings as a base line figure. Check to see that you have spark to both plugs. While running, remove one plug wire, RPM's should drop. Replace plug wire and pull other plug wire. Again, RPM's should drop. If pulling either plug wire does not drop RPMs, that cylinder is dead. Does the motor have more power running with the cover off?? If it does, you probably have an exhaust leak, allowing exhaust gases into the cover, choking out the carb. Are there any signs of a previous overheat? Perhaps a water pump was installed and the shift rod connector was improperly installed, that can cause your shifting problem.

Read this too! http://forums.iboats.com/showthread.php?t=158086

 

[wolfbaysailor]

Re: Evinrude Yachtwin 9.9 Help

Gees, where to start....oh yea..

Welcome to iboats.

You'd be well advised to find a factory service manual for your motor for starters. Since this is a new to you motor, I'd take compression readings as a base line figure. Check to see that you have spark to both plugs. While running, remove one plug wire, RPM's should drop. Replace plug wire and pull other plug wire. Again, RPM's should drop. If pulling either plug wire does not drop RPMs, that cylinder is dead. Does the motor have more power running with the cover off?? If it does, you probably have an exhaust leak, allowing exhaust gases into the cover, choking out the carb. Are there any signs of a previous overheat? Perhaps a water pump was installed and the shift rod connector was improperly installed, that can cause your shifting problem.

Read this too! http://forums.iboats.com/showthread.php?t=158086

Thanks for the quick reply (and the link!) and I apologize for the broad scope of the original post. I will try your suggestion. I also have another browser window open, shopping for a service manual.

More info...yes, a water pump and impeller were recently installed. The headgasket was also replaced. I purchased this motor, checked it out on a saw horse with earmuffs prior to installing on the sailboat. Everything seemed fine, good stream, etc. However, on the first voyage, the stream stopped and it overheated. THis resulted in the above mentioned repairs. It should be noted that the original mentioned problem (weak thrust) was present on the first voyage as well...

 

[samo_ott]

Re: Evinrude Yachtwin 9.9 Help

How much does your Hunter 25 weigh? I use to have a 9.9 yachtwin on my Seafarer 24' (those are sailboats for the rest of you powerboat guys) and it was a heavy boat, around 4,000 lbs and the 9.9 moved it well. Took time to speed up and slow down due to the momentum though. The ideas that have been posted so far are good ones. If it has overheated, checking the compression is a must. And if the 'pee' stream ever stops again, do not use the motor whatsoever (think of an auto with no coolant in rad) until the water pump/issue is fixed or you could fry it.

I currently have a friends 15hp sitting in my garage (same engine) that the pee stream went down to a trickle and my friends kept running it till it died... sigh... the thermostat housing and head paint are now black and peeling and the compression is down in the low 50's or so... way too low. So it needs a rebuild.

 

[wolfbaysailor]

Re: Evinrude Yachtwin 9.9 Help

How much does your Hunter 25 weigh? I use to have a 9.9 yachtwin on my Seafarer 24' (those are sailboats for the rest of you powerboat guys) and it was a heavy boat, around 4,000 lbs and the 9.9 moved it well. Took time to speed up and slow down due to the momentum though. The ideas that have been posted so far are good ones. If it has overheated, checking the compression is a must. And if the 'pee' stream ever stops again, do not use the motor whatsoever (think of an auto with no coolant in rad) until the water pump/issue is fixed or you could fry it.

Displacement is approx. 4400 lbs...just as a point of reference, my brother's 5hp moved the boat much better.

Regarding the pee stream, it looked fine when we left the dock. 10 minutes (or less) into the voyage, my wife noticed it was not working and we shut it down immediately. No idea when it stopped, but I know it doesn't take long...at least we didn't let shut down of it's own accord.

 

[wolfbaysailor]

Re: Evinrude Yachtwin 9.9 Help

Gees, where to start....oh yea..

Welcome to iboats.

You'd be well advised to find a factory service manual for your motor for starters. Since this is a new to you motor, I'd take compression readings as a base line figure. Check to see that you have spark to both plugs. While running, remove one plug wire, RPM's should drop. Replace plug wire and pull other plug wire. Again, RPM's should drop. If pulling either plug wire does not drop RPMs, that cylinder is dead. Does the motor have more power running with the cover off?? If it does, you probably have an exhaust leak, allowing exhaust gases into the cover, choking out the carb. Are there any signs of a previous overheat? Perhaps a water pump was installed and the shift rod connector was improperly installed, that can cause your shifting problem.

Read this too! http://forums.iboats.com/showthread.php?t=158086

Apologies for being so long getting back to you. Preparing for and delivering two kids to college....

So, I did the spark plug test. Pulled the top plug wire and RPMS dropped as expected. Pulled the bottom wire, got a pretty good shock and the engine died. I'm showing my ignorance here, but it seems getting shocked is probably significant. Bad wire?

 

[iwombat]

Re: Evinrude Yachtwin 9.9 Help

Getting a good shock is sort of normal. There's a lot of voltage there, and you're a pretty quick route to ground. Next time try a glove

Test indicates both cylinders are firing.

 

[wolfbaysailor]

Re: Evinrude Yachtwin 9.9 Help

Getting a good shock is sort of normal. There's a lot of voltage there, and you're a pretty quick route to ground. Next time try a glove

Test indicates both cylinders are firing.

Will do on the gloves! Thanks.

In my original post I mentioned that water is dripping from the bottom of the engine cover. SHouldn't water enter through the intake and exit from the telltale only? I see water puddling inside the engine compartment. Is this an indication that it may be getting in the cylinder(s) as well? I can not see where it is coming from.

 

[wolfbaysailor]

Re: Evinrude Yachtwin 9.9 Help

Getting a good shock is sort of normal. There's a lot of voltage there, and you're a pretty quick route to ground. Next time try a glove

Test indicates both cylinders are firing.

I'm back with an update.

After much reading, I decided to rebuild the carb. When I got it apart it looked quite clean, but I went through the process anyway (it's good for me ). During the reassembly/installation I discovered that the throttle was never getting to the WOT position. I now believe this to be my biggest problem all along. Long story short, the motor is pushing the boat very well at this point. Weather permitting, I'll be doing a more extensive test this weekend. But....and this was also a problem from before....

The motor does not start when cold. Bulb is tight, choke lever is working, etc. If I use a tiny squirt of starter fluid, it fires right up, runs smooth and I have no trouble stopping/starting after that. If it sits over night, it resists starting without a little snort. Any assistance as to where to go from here would be helpful.

Thanks,
Jeff

 

[samo_ott]

Re: Evinrude Yachtwin 9.9 Help

If it needs a shot of quick start then the carb is not doing it's job. The low speed circuit would be the likely culprit.

What happened with the earlier issue you mentioned, water in the cowling? That's a leak somewhere. Maybe the pee hose is loose? Maybe the head gasket, exhaust cover gasket or base gasket. It should be found and fixed whatever it is.

And 2 kids to college... yikes... I only worry about getting my kid to daycare on time

 

[iwombat]

Re: Evinrude Yachtwin 9.9 Help

First, never use starter fluid. Use some premix if you need to manually prime.

Reading back, I can't see where you ever checked compression after the overheat. You should do that to see if your head gasket is still good.

Did you remove and clean under the core plug when you rebuilt? If not that's a good bet on your cold start problem. You should also remove the air cleaner and make sure the choke is actually closing when you pull it. That motor should start right up cold w/o any problems. The need to manually choke indicates one of about three things given where you are on this motor.

1) Choke not closing properly
2) Clogged carb
3) Float set too low

 

[wolfbaysailor]

Re: Evinrude Yachtwin 9.9 Help

If it needs a shot of quick start then the carb is not doing it's job. The low speed circuit would be the likely culprit.

What happened with the earlier issue you mentioned, water in the cowling? That's a leak somewhere. Maybe the pee hose is loose? Maybe the head gasket, exhaust cover gasket or base gasket. It should be found and fixed whatever it is.

Doesn't appear to be a loose pee hose nor leaking in the area of the head gasket. I see no water on the engine at all....just coming out the bottom of the cowling. Maybe that's pointing to the base gasket?

And 2 kids to college... yikes... I only worry about getting my kid to daycare on time

I keep reminding myself of the "raise" I'll get in a few years....

 

[wolfbaysailor]

Re: Evinrude Yachtwin 9.9 Help

First, never use starter fluid. Use some premix if you need to manually prime.

Reading back, I can't see where you ever checked compression after the overheat. You should do that to see if your head gasket is still good.

Did you remove and clean under the core plug when you rebuilt? If not that's a good bet on your cold start problem. You should also remove the air cleaner and make sure the choke is actually closing when you pull it. That motor should start right up cold w/o any problems. The need to manually choke indicates one of about three things given where you are on this motor.

1) Choke not closing properly
2) Clogged carb
3) Float set too low

The head gasket was replaced after the overheat...

I did not remove the core plug since the kit did not come with a new one. I will do that. I verified that the choke is closing properly and I was very careful in setting the float and I am pretty confident I got it right. Will certainly double check when I clean the core plug, though.

As for the starting fluid, I will stop using it. I did a fairly extensive search prior to this post and saw all of the warnings. Thanks.

Jeff

 

[iwombat]

Re: Evinrude Yachtwin 9.9 Help

I think cleaning under the core plug will probably do it for you. Don't forget to retorque the head bolts after a few more hours of run-time.

 

[wolfbaysailor]

Re: Evinrude Yachtwin 9.9 Help

I think cleaning under the core plug will probably do it for you. Don't forget to retorque the head bolts after a few more hours of run-time.

Thanks...I have a feeling I am about to ask a stupid question, but should I get a new rebuild kit and replace the gaskets again? The float bowl gasket is rubber and can probably be reused, but the manifold gasket is not rubber. The engine has been run for at most an hour since the rebuild.

Thanks again for all of the help.

 

[iwombat]

Re: Evinrude Yachtwin 9.9 Help

You _might_ need a new manifold gasket, but probably not. Take it off and see. If it comes off intact, you're good to go.

If memory serves, the core plugs on this carb are all on the outside. So, unless you want to double-check the float you don't even need to split the carb.