69 Evinrude ski twin 33hp

[Jgoodman18]

I recently bought a not running 1969 Evinrude ski twin 33hp. I did a tuneup, lower unit reseal and impeller. She fired right up and ran well but it was not pumping water through the engine. The old impeller was in one piece so I have no reason to believe that there is anything blocking the waters path. I stuck a hose in the water bypass with the engine off and still did not get any water through. I was able to get air to pass through so I know it’s not completely blocked. Does anyone have any ideas what may be going on?

 

[racerone]

Are you running it in a test bucket ??-----If that is a YES , the water level MUST be 6" above the water pump.

 

[Jgoodman18]

Yes it is in a bucket. That is good to know. The bucket I have is not deep enough to achieve that.

 

[racerone]

Hopefully you did not ruin your new impeller.-------No alarm / warning / shutdown system on that beautiful / simple motor.-----So put a new impeller in it again.

 

[boobie]

Before you put a new impeller in it, try it in deeper water.

 

[jimmbo]

When you had the water pump apart, you did reinstall the key on the driveshaft that engages the impeller?

 

[Jgoodman18]

The driveshaft had a nipple on it instead of a key. I’m assuming that it is sufficient to spin the impeller.

 

[F_R]

If by a nipple you mean a round pin, that is correct for a 33hp.

 

[boobie]

Did you ever try it in deeper water ??

 

[Jgoodman18]

Not yet. I won’t be able to put it in the water until next weekend and I don’t want to buy a test tank or anything.

 

[Jgoodman18]

Got it in the water and the impeller is working beautifully but I am not getting any power while in gear. The engine will rev up fine in neutral but when I put it in gear it doesn’t rev at all. I don’t have a tac on it but would estimate I’m hitting 1000 rpm at wot and I’m topping out at 7 mph. Tried adjusting the carb but had no luck. It runs the best with both low and high side adjustments run all the way in.

 

[racerone]

Sounds like it is running on 1 cylinder.----Check fuel pump diaphragm for a hole.------Makes no sense that it can run with needle valves all the way in.-----Time to do a complete inspection of this simple / well built motor before you venture away from the dock.----Does spark jump a gap of 5/16" on both leads with a snap you can hear , yes or no ?

 

[Jgoodman18]

Pulled the plugs and yes it looks like the lower cylinder is not firing. They both tested fine before I put it in the water. Going to do some more investigating now.

 

[boobie]

Do a cylinder drop test on it.

 

[Jgoodman18]

Found the issue. Was a short to ground on the cut out switch. Fixed that and now she hops up on plane and tops out around 25 mph. I’m pretty happy with this but am curious if this is what I should expect out of this motor.

 

[jimmbo]

If on a 14 ft boat, 25 isn't too bad, if on a 16 ft it is doing very well.

What boat is it on, what prop is on it, and do you know what rpms you are getting at WOT? Your engines WOT rpm range is 4000 - 5000.

If you were looking at the old Evinrude brochure or owners manual you might have seen "Slow Troll to over 32 mph". that doesn't mean any boat with that motor will have a Top Speed of 32mph.

 

[Jgoodman18]

It’s on a 14’ tri hull. No idea what prop is on it or the rpm range at WOT. Based on the sound of the motor I would say I’m probably hitting the lower end of that range. Thanks

 

[boobie]

What's the boat rated for horsepower wise ??