About Ready to Give Up

[zteeters]

Here's the story,

I have a 1958 Johnson 35 H.P. Super Seahorse model # RDS-20
I have rebuilt the carb step by step with the original repair manual.

Here's the Problem,

Very hard to start, I have to pull the choke turn it over, push in the choke continue to crank it while feathering the throttle, then it will start, If It dies repeat this procedure, with each time taking longer to fire up.
Once running it runs great 1/4 1/2 and full throttle, but when I take it down to Idle, it stall's, and I have to go through the whole start up procedure again if it is been running for a while it could take up to 30 min before it fires?

I guess my major problems is at lower throttle speeds Any help / advice . Or should I just take it to the repair guys who wants 200.00 just to look at it?


If I didnt own JUNK what would I have?

 

[patrickray]

Re: About Ready to Give Up

Have you checked compresion?

 

[Shizzy]

Re: About Ready to Give Up

have you checked the engine synchronization?

 

[zteeters]

Re: About Ready to Give Up

Yes comppression was 95-95

As far as engine synchronization ?????????????? thats where im LOST.

 

[samo_ott]

Re: About Ready to Give Up

Sounds like low speed circuit in the carb. Did you remove the core plug and clean behind it?

 

[cc67]

Re: About Ready to Give Up

Here's my $.02. I've rebuilt a half dozen motors in the past year and every one that had symptoms like yours I remedied by replacing the plug wires.( I rebuilt the carbs and checked the coils,points etc). Even though they look good they are still 50+ years old. If you haven't done this, give it a try.

 

[zteeters]

Re: About Ready to Give Up

Thanks CC67, Ill do just that, good point 50+ years old. doing this should be less than 200.00. I appreiciate that suggestion, will post the results as soon as I can..


thanks again

 

[zteeters]

Re: About Ready to Give Up

Samo_ott.

Core Plug? I believe I know what ur talking about? I was told they are called welch plugs, and was also told that they looked new (newer) and that I should not remove them? Was this bad Info?

 

[jbjennings]

Re: About Ready to Give Up

I'll probably get scolded for saying it, and this probably isn't your problem. But if your gauge is right, 95 lbs. isn't so great and low compression usually rears it's ugly head on idle. That being said, I also believe it's weak spark, slow idle circuit, or bad synchronization of the carb butterfly. One question---have you ran it wide open to see if it would plane? If not, then one more question---when you have it running, have you pulled a plug wire and see if it makes any difference and if so, have you put it back on and then tried pulling the other plug wire to see if that has any effect. If pulling both plug wires has an obvious effect, then I'd look at the carb synchronization because it's easy, and if it's o.k., then I'd look at checking the slow speed idle circuit in the carb. Lastly, I'd spray some propane with it running in the area of the carb and intake manifold to check for vaccuum leaks.
come on, you can WHIP that thing into shape!
JBJ

 

[F_R]

Re: About Ready to Give Up

Any and all 1958 OMC motors have bad ignition coils if they haven't already been replaced. You are wasting your time dinking around with the carburetor until you address the coil problem. In fact if you had removed the flywheel first it would have been 10 times easier to get the carburetor off and you would have seen the coils.

 

[simbot]

Re: About Ready to Give Up

My 58 has a fuel econimizer on it, its a bar that has a flat screw lock on it, I ran with it set up and noticed my butterfly valve wasn't openning fully only about half way, so i set the lock back till it openned fully. Here is my point, once i did that I was able to set my idle stop. That screw was just turnning and it wasn't doing anything untill I reset the economizer. Maybe you should screw in the stop to a low enough idle then set the idle lock before it gets too low and dies.

 

[samo_ott]

Re: About Ready to Give Up

Samo_ott.

Core Plug? I believe I know what ur talking about? I was told they are called welch plugs, and was also told that they looked new (newer) and that I should not remove them? Was this bad Info?

Lotsa of good ideas to look into. Have you not looked at the coils yet? That is a biggie, I assumed it had been done. Here are pics of my recent '54 25hp that I opened up. And it actually slightly ran!

So after you check the coils if you still have a prob I would always clean behind the core plug (size of a dime on top of carb) as the low speed circuit is there. It should always be checked in my opinion and if you notice, a new core plug comes in all the carb kits exactly for that reason.

 

[zteeters]

Re: About Ready to Give Up

Well it looks like I have alot of work to do, so Ill get back to you guys after I try some of these remidies, thanks for all the friendly advise.....

 

[wbeaton]

Re: About Ready to Give Up

If you didn't remove the welsh plug you didn't clean the carb. So I assume you didn't use a rebuild kit either. How was the carb float? Like its been said, check those coils. Originals have a 100% failure rate. 95lbs is marginal, but it should still run. Give it a decarb once you have it running right. You shouldn't have to feather the throttle on start up. With the engine neutral, turn the throttle all the way open and try to start it. Once it fires, turn the throttle down. There is a little seal on the tube that runs from the float bowl to the carb throat. Did you replace it? Did you set the low speed jet to 1.5 turns out and the high at 1 turn? These are just starting points. You have to make the final adjustments on the water.