M9.9c

[bbstacker1]

I was just given this engine and know nothing about it other than the following. Previous owner said the engine ran fine then it just stopped, loosing it's fire. I checked there is no fire to the plugs. I believe at some point the engine was converted over from a tiller model to an electric start with remote controls as that is how it is now configured. I hooked up a battery to it and it cranks over with no problem. The only thing I noticed on the motor is that the ground strap between the leg and mounting bracket had heated up at some point, melting the cover off the wire, and that the wire was no longer connected, I reconnected the wire. Would I be wrong to assume that either the coil or CDI box would most likely be the problem. The engine seems to be in very good condition outside of the no fire issue. Are there any particular problems with this model and what year(s) were they made. It is a Tohatsu M9.9C, 355A 661XX. Thanx

 

[Sea Rider]

Re: M9.9c

No spark firing is generally related to Stop Switch, Exciter Coil, CD, Ignition Coil, Plug failures, get yourself a service manual and start troubleshooting electrically that engine. Replace damaged cables with same wire gauge.

Happy Boating

 

[bbstacker1]

Re: M9.9c

I really don't want to go to the expense of buying a service manual for the engine, not trying to be cheap, just that the motor was given to me and I really don't even have a use for it. I just thought it might be something simple or easy to check and diagnose. The engine itself is in very good condition, it has a compression of 155-160 on both cylinder (I am used to seeing 65-90 on the old J/E's that I tinker with) and is real clean. It is a long shaft with electric start and I was given the remote controls for it also. The only thing I noticed, it sure is heavy for being only a 9.9

 

[pvanv]

Re: M9.9c

I really don't want to go to the expense of buying a service manual for the engine, not trying to be cheap, just that the motor was given to me and I really don't even have a use for it. I just thought it might be something simple or easy to check and diagnose. The engine itself is in very good condition, it has a compression of 155-160 on both cylinder (I am used to seeing 65-90 on the old J/E's that I tinker with) and is real clean. It is a long shaft with electric start and I was given the remote controls for it also. The only thing I noticed, it sure is heavy for being only a 9.9

You're kidding, right? You want to repair it, but don't want to get the manual to find out how? Come on -- that's just guessing. If there's no ignition, it could be as simple as the stop switch has lost the clip, or is shorted... or it could be as involved as a bad CD.

There are no shortcuts to diagnosing the ignition system. Everything in the ignition system is reasonable to test and diagnose, but you need the information and procedures in the Factory service manual, available from any dealer, including me, for about $48 bucks.

So, if you want to guess, just start buying parts and changing them, until it works again. That is by far the most expensive way to troubleshoot and repair an OB. Otherwise, a manual is a wise, and cost-effective investment, and can be sold along with the motor (as a value-added bit), should you choose to sell the motor in the future.

 

[bbstacker1]

Re: M9.9c

No, I'm not kidding. As far as repairing it, I will most likely, at some point, check all the wires to try and make sure none have a break. But for now I will park it in a corner of my garage and there it will set unless I find someone that wants to tinker with it. Right now, I don't even know what year it is to check for parts availability.

 

[pvanv]

Re: M9.9c

Year is irrelevant when servicing a Tohatsu/Nissan OB. The model and serial are the defining info.

For ignition testing without manufacturer-specific data, you need to determine whether you have spark at all (in your case, the answer seems to be no), and then start dividing up the system (assuming you understand how it all works), into half-way test points, to see whether the problem is upstream or downstream of your test point. Before getting too far involved, verify that the stop switch is working correctly, and that the clip is inserted under the head of the stop knob.

See if you have an adequate signal going into the ignition coil (you should have the manual to determine what is adequate).

If you do, then do resistance tests on the coil to verify whether it's good or bad.

If not, see if you have good exciter and trigger signals going into the CD. (same advice from the manual applies).

If the exciter and trigger are working, do resistance tests on the CD to verify whether it's good or bad. (same advice from the manual applies).

Armed with an accurate diagnosis, you will know what part to replace. But you will want the manual to see what the test limits are... And there are far too many to list them in a forum post.

 

[bbstacker1]

Re: M9.9c

Pvanv, I do appreciate your input and what you told me will give me some things to look at. The motor is really a back burner item for me at this time, but in the future if I do decide to get into it I noticed you said I could get a manual from you can I also get other parts if needed. The model and ser# are in my first post if required. Thanx

 

[pvanv]

Re: M9.9c

Sure. No problem. I'm a dealer, so parts are what we do. BTW, The serial is the 5-digit number that you have XX for the last 2 digits.

 

[bbstacker1]

Re: M9.9c

pvanv, the whole number is 66172. Thanx