Need help with 1968 40 HP Big Twin Evinrude

[andreipou]

Don't think it's a match (shape of the original pump and diaphragm is slightly different). Can pull out the diaphragm on yours and use it as a template for a new one. If the diaphragm isn't split or holed, chances are it has taken a set -- more like cardboard than flexible rubber.

I was talking about gasket between pump and head.
If the holes on new pump match holes on the old one, I should be able to replace whole pupm.

 

[oldboat1]

Yup. Agree. (Sorry....)

 

[andreipou]

I finally got to it and figured out.
Pump works fine and pumps jet of gas out of carb hose.

So, I took carb off and disassembled.
Right away I saw large drk piece in high speed pipe.
And bunch of small pieces in the bowl.

Looks like cork washer between high speed pipe and bowl body fell apart into bunch of pieces.
Cleaned all, blew with air and now it runs as champ again.


I never had this problem before.
Carb was rebuilt previous season.

Anyone had this?
Defective cork?

I did not see any non-cork washers for that.

What if I make one out of Teflon?

 

[racerone]

I think the factory replacement is quality stuff.---Not cheap.----Not made of cork.

 

[andreipou]

I think the factory replacement is quality stuff.---Not cheap.----Not made of cork.

who sells it?

 

[racerone]

Most good BRP / EVINRUDE / JOHNSON dealers would have it in stock.

 

[andreipou]

my experience: you order by part number. you get the cork one. I ordered many times for different OMc motors. It always came as cork.

 

[racerone]

Sorry, you have to find a better dealer.----Perhaps one with a grey haired parts man / mechanic.----This should be easy !

 

[andreipou]

Unfortunately, it is not easy.
All dealers\mechanics around only work with Mercury\yamaha\Honda.
Nobody wants OMC.
One guy is about 2 hr drive away.
So, it is only mail orders for me...

 

[oldboat1]

If talking about the boss gasket down in the bottom of the bowl (end of the nozzle), I wouldn't worry about the cork ones. Should easily last until the next cleaning, and probably longer.

 

[andreipou]

It is part 78 on this diagram

http://ww2.iboats.com/Carburetor-Gr...807742--session_id.215563098--view_id.1550182

And it was replaced last season and it is the problem

 

[oldboat1]

yup. See there are a couple of pns, guessing one is the non-cork one (need that grey-haired dealer, unless you can find one under the pn -- more expensive one).