TOPIC: 1956 Evinrude Fleetwin won't stay running.

I bought a super clean 1956 Evinrude Fleetwin 7520 last year. It has almost 60 lbs in both cylinders (New Rings). I checked the plugs, pulled the flywheel and inspected the coils and points. All looks new. I pulled the powerhead and put in a new impeller. All seems perfect.

I put it in a tank and started it. It fired and ran real great. After dialing in the low and high speed knobs it ran great for about 3-5 minutes. Then it started sputtering and stalled. After many pulls it would start again, but will only run for a minute. My arm finally got tired.

The tank is a good rebuilt tank and works perfect on my Lark Twin- Had that one out on the lake last week.

I do notice a lot of white smoke during start up. I also notice exhaust in the fuel tank. Is this normal?

Any ideas on my Fleetwin?

Mark

Pressure tank? Are you using the same hose on the Lark? How is the head gasket?

So this is a Pressurized dual hose tank Right??? Like this one...

Yes that is

Exhaust in the pressure tank means excessive "blow-by", filling the crankcase with exhaust, which the motor will not run on. Three possibilities, one being not enough oil in the fuel mix until the rings seat. Should be 16:1. Second possibility is when the pistons/rings were installed into the powerhead, installer did not ensure the ring end gaps were opposite each other. Third, installer used the wrong rings and end gaps are excessive. Should be .007-.017.

Rings are positioned in the grooves with a pin on these motors.-Would be nearly impossible to install them incorrectly !

Thanks, Professor. Yeah, had a D'OH! moment on the way to work. Glad you corrected for me.

What is indicating to you that you are getting exhaust in the tank? It is normal for a vapour to emit from the tank for a few min after opening the tank. I can't see how exhaust could get into the tank but white smoke is a sign of steam and you probably are getting water into the engine. 60psi is pretty low for compression so maybe a complete overhaul or powerhead swap is in order
Al

I was thinking 60lbs was a bit low. I have seen low hundreds in a good runner FT. Blow-by in the tank isn't a show stopper. You will always get a little bit.

Sounds like piston and ring clearances need checking.

When I run one of these in the barrel/shop I usually hang a little tank on the rafters and gravity feed it. Works just fine for the things you can mess with in the barrel.

professor,

UNFORTUNATELY, the rings MAY be improperly installed. - I've seen WIERDER things.
(The reason that nothing can be made Idiot-PROOF is that idiots are so ingenious.= CHUCKLE.)

yours, satx

Yes if the rings have a top and bottom, in the case they are tapered asymmetrical, L shaped or something like that you can get them upside down even with anti rotation pins. But I am sill not sure if you could get them in the bore though.