1974Johnson 25 [25RL74M] help

[Bevo2000]

Hello all,

I recently nursed this motor back to life by getting lots of help from the forum. However, because this is my very first outboard motor, I have some questions that a novice usually asks.

Question #1, in the first video, you can see that as soon as I turned the throttle control to slow, the engine would shut off. Where can I find the idle adjustment screw on this motor? I have a service manual but couldn’t find the info regarding this issue.

Question #2, in the other video that lasted 11 seconds, you can see that there’s no water exiting the exhaust at all. And even if I let it run for another minute, I still won’t see any water coming out. Afraid that I might damage the motor, I turned it off, However, if I start the motor up again, water will usually exit the back just like the other video. This happens maybe 3 out of 10 times. Note that I have replaced the thermostat today. Is this a problem and if so, how do I troubleshoot the issue?

Video #1:

Video #2:

Thanks for your hep.
Dustin

 

[racerone]

Water level in your test bucket is way to low.----That is a plain fact.----Add another 12" of water to it.----Get a bigger bucket !---Or test on a boat in the lake.

 

[hardwater fisherman]

The motor has/had a idle stop screw... Follow the tiller handle too the back and look under the vertical gear... That is where the idle stop screw and spring will be... It may be a plastic screw..The photo is of the gear and the screw threads into the lower hole...If the screw is missing or broken/bent you can put a bolt with a nut on it to keep the bolt in place... or I used a bolt with a spring and it worked well..

 

[Bevo2000]

Is that the adjustment screw Hardwater? And as for the water question, should I expect to see water spitting out every time if I tested it in a lake (impeller has been replaced)?

 

[racerone]

On the boat in the lake.-----Water should come out at the exhaust relief seconds after start up.--------When you installed the lower unit was the water tube installed in the exhaust housing first.----You are sure tube is in the grommet at the top and in the grommet at the pump outlet ?

 

[Bevo2000]

Racerone, yes to both of your questions. What bothers me is why it only happens (no water) some and not all the time, when the water level inside the bucket is the same every time?

I hate having to pull out the lower unit again to inspect because it was a pain to put it back the first time. But if I don’t see water come out at every restart while in the lake, then that’s what I will have to do.

 

[racerone]

You need much more water in your test bucket !!----The pump is not self priming--------Not sure why you would argue that..

 

[jimmbo]

Is that the adjustment screw

Yes that is the idle stop screw

 

[Bevo2000]

You need much more water in your test bucket !!----The pump is not self priming--------Not sure why you would argue that..

I am not questioning your suggestion at all, it’s the programmer in me that was curious.

 

[Bevo2000]

Thanks Jimmbo!

 

[Bevo2000]

racerone and all the pros, I need your advice please. I have been suspecting that motor is not getting enough sparks so I followed directions In the manual to test the spark, and I did not get any spark with a gap of 3/8” or 5/16” and only got consistent sparks with a gap of 1/4”. Note that the other plug was fine. The manual then continued with requiring the purchase of a Steven S-80 or Metc-O-Tronics M-80 in order to continue the troubleshooting. I really don’t want to go down that path, so do you have any suggestions? Thanks in advace

 

[racerone]

Clean and set breaker points.----Replace condensers.----Test spark again.

 

[Bevo2000]

Thanks racerone. I would like to replace the breaker points (instead of cleaning). Could someone please tell me what the part number is PLEASE?

 

[racerone]

My approach would be to clean the points and see if strong spark is present on both leads.-----Then perhaps replace them if they are totally pitted / damaged in some way.------Oh and I do have a MERC-O--TRONIC magneto analyzer.

 

[Bevo2000]

Thank again racerone