1967 9.5 evinrude, still lean sneezes after completed teardown and rebuilt, help plz

[Jigsaw404]

Hey
I have a 1967 evinrude 9.5. I got it off a friend for free, it was in rough shape but started and had a major lean sneeze. After doing lots of research on this problem I decided to completly tear down my newly acquire evinrude. I am a novice so I took my time etc... I got all new intake/exhaust seals, carb kit, new fuel pump, top and lower crankshaft seal. All new electrical(coils,condensers, points,wires,plugs).

Ok, so I went to start it today, and it did, ran like a champ at high speed, but still has the same lean sneeze. The lean screw doesnt seem to do to anything and appears in good shape. half choke and the lean sneeze is gone but run way to high I can idle it.


Compression for some reason goes up to 80-90 immediatly drops to 0( needle goes up and down), on each cylinder - is this normal? or should it hold its compression?

ps, the only thing I didnt change is the pistons, so I tore it down to the block without spliting it.

 

[tomhath]

Re: 1967 9.5 evinrude, still lean sneezes after completed teardown and rebuilt, help

I'd keep looking for why the lean screw doesn't change anything. Did you pry the welch plug(s) out and clean under them? That's critical to the idle circuit.

 

[the machinist]

Re: 1967 9.5 evinrude, still lean sneezes after completed teardown and rebuilt, help

I just had one of those 9.5s in from a young neighbor kid to find out why it would hic-up / miss at a mid throttle. Tore that carb apart twice, & again after I got a carb kit for it.

I checked everything, (I thought). I had not checked the compression & it had new plugs that he had put in it. When I pulled the plugs, someone had set the plug gaps at between .012 & .015. I just regapped the plugs & it runs fine now. Don't take anything for granted no matter how new the part looks.

 

[Jigsaw404]

Re: 1967 9.5 evinrude, still lean sneezes after completed teardown and rebuilt, help

I did take the welch plugs out and cleaned everything, to me its clean.

an update - I took off the armature plate today and filled the crankshaft cavity with wd40 and hand cranked the crankshaft, and air bubbles were coming out of the seal. I guess I damaged it while putting it in.
So ill replace the seal this weekend, but is there a sealant that I have to put around the seal where the block and seal meet? to make sure the air doesnt get out of the seal and block.

points are set at .020 at tdc.

 

[jbjennings]

Re: 1967 9.5 evinrude, still lean sneezes after completed teardown and rebuilt, help

The upper crankshaft seal should not need any sealant between the metal seal and the block. You should not have seen any bubbles coming from anywhere except the rubber part of the seal if it were bad. If it's leaking between the metal parts of the seal and engine, something is wrong. If it were doing that, I wouldn't see anything wrong with using a a thin film of sealant on the metal.
If your low speed needle isn't having an effect, then your carburetor is still dirty or you have a bad vacuum leak (as you suspect).
Good luck,
JBJ

 

[Jigsaw404]

Re: 1967 9.5 evinrude, still lean sneezes after completed teardown and rebuilt, help

Alright here is an update,

So I put in another upper crankshaft seal, and took the carb apart. in my history I have never taken out the plastic plug below the bigger welch plug. I cleaned in there made sure all three holes were clean.Put it back together and started like usal, half pull, ran at idle fine in the barrel( could not tell the high speed).
Long story short, went to the lake to try it out. firstly, I have a 12ft aluminum boat and it didnt not plane with two people, avreage size, just rooster tail. Secondly, at idle the same lean sneeze. arrgh.
Back on the trailer it goes, bring it home and take the carb apart, notice the float was adjusted in the opposite direction. Out of curisity, I check the upper crank shaft seal, now, the bloody rubber part is bubbling.
My question this time is, If I have the plugs in and I crank it, is it normal to have air pushing out of the crankshaft seal since its creating pressure with my no fire?

 

[nctlspider]

Re: 1967 9.5 evinrude, still lean sneezes after completed teardown and rebuilt, help

Can you post a pic? Sometimes a picture is worth a thousand words. Sorry for your frustration, someone on here ought to be able to help you figure this one out.