First trip on the lake failure

[spy1309]

The first trip ROYALLY SUCKED besides the fact that such an old boat was a head turner I can t say the same about the ride.
The motor started first key, idleing so so, at troling speed you can feel that the engine was out of breath, I couldn t go more than 8 - 10mph, as soonest I try WOT the engine was boging down and die ....not pleasant on Michigan lake and 30 feet away from the shore stone wall.
I can say I am dissapointed and I decide to scrap any trips for this year I will try to overhaul the piston rings .
The compression for both is ~100 +/- 5psi, now if I disconect the cyl #1 the RPM does not drop very much, if I disconnect #2 there is a significant drop in RPM, I checked the spark on the cyl #1 is nice and blue, sparl plugs are gaped and new J4C, after the trip they were wet with slightly oily residue.
I don t know why it was going so bad at WOT I suspect flood of the engine, the fuel pump and carburator are freshly rebuild, in the carburator kit came a spring for the needle but my old one did not have one so I did not installed it, another thing is I don t know where is the vent for the carburator so I don t know if is working or not.
Any opinions are welcome.


PS- Motor 1960 Johnson 40hp

 

[Silvertip]

Re: First trip on the lake failure

If pulling #1 plug wire resulted in little or not change in engine RPM but pulling #2 did produce a significant change, that says #1 cylinder is either not firing or is not getting fuel. Compression is very important but with the figures you provided, that's not the problem. I would recommend that you take the boat out again, and when advance the throttle, have someone squeeze the primer bulb. If the engine comes to life there is a carburetor or fuel pump issue. You could also mix a small amount of fuel/oil in a spray bottle. With the air box removed, spray a little extra fuel into the carb. If the engine responds, you've isolated the carb as the problem. The fuel tank must be vented. If both plugs were wet with fuel oil, I'm leaning toward a weak spark issue on this engine.

 

[spy1309]

Re: First trip on the lake failure

Also important then motor was ideling poorly with the front cover from the manual puller closed, when I was opening it the idel would increase nicely.
Now I took the spark plug out and crancked the engine the spark at the spark plug tip is nice strong blue, it can change when the spark plug is inside?
Also the type supposed to be J4J but they are not made anymore.
I forgot to mention coils are new, points to gapped at 0.20.
It looks like based on my experience with cars that is somethinh wrong with the timing, something strange on the back of the lower cylinder block is an aluminum rivet head loose and thru there some gas is leaking when the engine runs.
Now somebody on the forum said the unburned gas from the top cylinder goes to second is true?
I am running out of ideeas, if my compression is ~100 what is the standard lets say when the engine is pretty new?At least I will not try to replace the piston rings.

 

[Silvertip]

Re: First trip on the lake failure

If having a cover open makes the engine run better, that says there is an exhaust leak inside the engine cover. That exhaust creates an improper fuel/air mixture which can cause problems. Yes -- a plug can fire outside the engine but not under compression. That's a very good sign of weak spark. A spark can be weak regardless whether timing is advanced or not so I don't feel timing is an issue. I would look for an exhaust leak (base gasket perhaps).

 

[cr9c1]

Re: First trip on the lake failure

You said points were happed at .20, but did you mean .020? .020 is the correct setting.

Just because you have a spark when you check it doesn't mean under a load it does. I would go ahead and replace both coils ($20/piece Sierra) and new points and condensers ($14/sierra)

But check the fuel issue first, as previously mentioned.

 

[larky]

Re: First trip on the lake failure

you also mention the J4J is not made anymore, thats correct, but they have a replacment its J4C gaped at .030, avalible at any napa, or similar store

 

[tashasdaddy]

Re: First trip on the lake failure

the spring belongs on the needle. also sounds like the float many need adjusting. i'd do that, first, and the electrics, before going to a ring job. a decarb might bring the compression up.

 

[spy1309]

Re: First trip on the lake failure

Thank you guys for ideeas, as I mentioned coils are new ( wires old ) new points so I try at least to rule them out but the wires, oh I have installed a new head gasket to just to be on the safe side.
Now in the manual I don t see any spring for the carburator needle, there was none when I took it apart so I have no ideea where the spring goes or how.
The float is the same cork old one and is adjusted to be paralel with the bowl edge.
It seems that I have to take it apart again and if this is the case I will take a look at the reeds to just to make sure that is nothing wrong there.


PS- After the link and sync the low speed needle works best at half turn counterclockwise not 1 and 1/2 turn at this setting it idles very poorely, the high speed jet same 1/2 turn any more than that speed up the idle way to much.

 

[larky]

Re: First trip on the lake failure

I think the spring that tashasdaddy is talking about is the spring or clip (basiclly a very small wire) that holds the float needle to the float so that there is more of a direct connection to each other. the spring comes with a new carb kit, so that is probally why you did not see one.

are you adjusting the carb needles at there respective speeds? meanning adjusting the idle at idle and the high speed needle at wot?
if you are and the idle is too high when you bring the throttle back down, try turning the idle needle out a little and that should richen it up a bit and slow the idle speed down

also what did you find with the possible exhuast leak?

 

[spy1309]

Re: First trip on the lake failure

The exhaust leak comes from somewhere down I see that there is a ruber gasket collar maby that is the cause of the leak for the exhaust allowing the gases to rise to the engine.
I will take the carburator and reeds assembly apart to check them, eventualy reclean the carb.
For some reason I think that the link and sync was not done correctly I will retry.

 

[spy1309]

Re: First trip on the lake failure

I don t want to open a new thread so I will continue here.
In my atempt to get things right ( I got pissed ) and that what is a boat good for if you can t ride it? I removed the carburator again it was clean as a whistle but to my surprise the carburator float nedle was with the pointy side towards the float arm also I put it this way because it was this way when I removed and cleaned the carburator so the old owner installed it the same way.
I took the manual and saw the the pointy side has to be in so I installed it the correct way put it back and I am waiting for the weekend for one last chance.
My question is this might be the reason that my engine was bogging down and having the plugs wet? I suspect that because of the needle the engine was getting flooded and never getting a chance to run right even after replacing the coils, points etc

 

[cr9c1]

Re: First trip on the lake failure

Absolutely. There was nothing stopping the flow of fuel from the engine so it was continuously pumping fuel into the carb. It also explains the wet plugs.

 

[clemsonfor]

Re: First trip on the lake failure

Yes that was the problem, that stops the flow of fuel in to the bowl, if it is upside down it will never stop the fuel flow, thus causing the motor to flood, and really flood, it will slow so much gas into the motor that it probably over flowed out of the carb throat, and just poured into the intake! Im suprised that the thing even ran at all, i have had mis adjusted floats and it wont even hit on that cyl b/c of excess gas! the little clip goes around the little groove on the needle and the clips over the metal tang on the float so that when the float falls it pulls the needle valve open and when the float rises it just followes it to seat against the seat. The needle valve has a point b/c if you looked at the seat it has a beveled edge around the hole and that point is forced into that hole by the float when the float bowl is full of fuel (when the float reaches parallel w/body) and thus shuts the flow of gas off until more is needed by a drop in the float!

Fix that and that is your problem, not saying you may not have others but that is the reason you wont idle and cant get WOT. Also you will now have to readjust your needle settings at wot and idle to compensate for the reduced fuel flow!

-NAte

 

[spy1309]

Re: First trip on the lake failure

You are correct that I have to readjust the needles low and high, now the low needle is 1/4 turn from the seated possition ( very lean) instead the customary 1 1/2 because of the flooding for sure.
I let you guys know how it will go.
Thank you all for reply.

 

[Evinrude Boater]

Re: First trip on the lake failure

I see you're still struggling to get your motor running smoothly. Have you been running it in the lake or just working in a tank or muffs? I still don't believe your 100 psi compression is a factor. Are both cylinders close in their compression?

 

[freddyray21]

Re: First trip on the lake failure

" see you're still struggling to get your motor running smoothly. Have you been running it in the lake or just working in a tank or muffs? I still don't believe your 100 psi compression is a factor. Are both cylinders close in their compression? "

"The compression for both is ~100 +/- 5psi, now if I disconect the cyl #1 the RPM does not drop very much,"

From his first post

If the float valve was in upside down there is a real problem there. Also the spring clip was a part used in the rebuild kits. Use it. It makes a difference. It helps the float pull the needle down. There had been a problem with the rubber tipped valves sticking. I believe the original was a steel valve, but use the clip.