40 HP Johnson Need Help

[Beeched]

I just acquired a 40 HP Johnson Motor. It is a model RDS-27A, S/N J2514055. It ran fine for about 3 hours. Was cruising around the lake, had to throttle down and it died. I had been trolling for about 1 hour before I went across the lake. I do have fuel through the fuel pump to the carb. The float looks bad but is totally free and the needle valves appear OK. There are two possibilities that I can think of, I need either a carb kit, a new carb, or possibly a set of leaf valves (reed valves). Any help would be appreciated.

 

[hondon]

Re: 40 HP Johnson Need Help

Could also have a pair of bad condensors, dirty points ,faulty vaccume switch or mercury switch.Compression releif valve could be hanging up if this is rope start.Bottom line. This is an oldie.Good luck.

 

[Beeched]

Re: 40 HP Johnson Need Help

Thanks for the good luck. I did find out that it is a 1965 engine. I have found a carb kit for it, am still looking for a set or reed valves. I will be checking the other things that you mentioned. If anyone out there has any info on where is a good place to get parts I would appreciate it.<br /><br />Thanks

 

[Billy Bob]

Re: 40 HP Johnson Need Help

Beeched<br /><br />I was told that if a reed valve went bad it would shot gas through the carburetor. Just what I was told, don't know if that holds water. ha ha ha Pardon the pun.<br /><br />Billy Bob

 

[fireman 757]

Re: 40 HP Johnson Need Help

I doubt that it is your reed valves. Have you been able to get it started since? Check for spark to the plugs first. If you have good spark to both plugs then rebuild your carb and repost what happened. If you do not have spark I would check my ignition coils first since they are the easiest and probably most suspect.

 

[JB]

Re: 40 HP Johnson Need Help

Hi, Beeched.<br /><br />Don't start buying parts until you know what is wrong. If you feel you must spend some bux, get a manual.<br /><br />Do you have a hot, blue spark to each cylinder?<br /><br />What happens if you squirt some fuel into the carb before trying to start it?<br /><br />Run a compression check.<br /><br />Buy or borrow (library) a manual.<br /><br />Let us know what you have found.<br /><br />Good luck.

 

[JB]

Re: 40 HP Johnson Need Help

Fireman.<br /><br />Didn't mean to step on your post. I was typing when you posted.

 

[Beeched]

Re: 40 HP Johnson Need Help

Billy Bob, you are 100% right. It will blow back into the carb if the reeds are broken. <br /><br />To all others who have helped so far. The spark is bright blue, electrical has been eliminated so far. Problem still tends to be in the delivery of gas. I do have a manual that I got with the boat. I am not going to get a chance to work on the problem till this weekend. I will let all know what turns out as I go along. You have all been a great help and I do appreciate it.<br /><br />Thanks again!!!!!!

 

[Beeched]

Re: 40 HP Johnson Need Help

Hondon, JB, Fireman 757, and Billy Bob. Thanks for all of your help, I put in the carb kit, removed and cleaned the fuel pump, it runs now. I do have a little of tuning to do to it but spent a very relaxing day fishing for Walleye and Northern. I have a new fuel pump ordered for it and will be putting it on. The old one will be saved for reserve if it is needed.<br /><br />All of you guys serve a fantastic need and to be able to get the help on these things is appreciated by all who you help.<br /><br />Thanks again.<br />Richard Kuhn