lost top cowling piece 1971 Johnson 50

[Jconnell43]

Long story short, I dropped the smaller top cowling piece in 30 ft of water.
Had unscrewed it for painting and didn't refasten.

15ft tri-hull was maxing out at usual 20 mph before loss.
After loss it sounded like it was missing at wide open.

Putting my hand over the hole where the smaller piece was made no difference.
Taking off entire cowling made it run fine.

Questions:
1.What is the purpose of this smaller piece?
2.What can I do to replicate its initial purpose, it's a lot quieter when I put my hand to cover the hole in the large cowling, I really don't want to buy an entire cowling
3.Does this opening have to do with intake or exhaust?

Thanks,
Jim

 

[jbuote]

Are you talking about the Tilt Handle and it's baffle?
Back of cowling and you could reach it and pull the engine to tilt it up from inside the boat?

That would have to do with intake, not exhaust.

 

[Jconnell43]

Exactly, the tilt handle piece.
It pulls air in from the back, maybe creates a little turbulence of the right measure?

 

[jbuote]

Well still not a pro.. LOL
Just speaking from my experience with my 50ESL71...

As far as I know, what you lost is just that..
A tilt handle.. Happens to have the air intake hole under it too..

The fact it runs better with the cowl off would seem to indicate either the intake hole in the cowl is blocked off (fully or partially) restricting air getting to the carbs, OR, there is an exhaust leak which is letting exhaust into the carbs because it's being contained by the cowl..

Running better with the cowl off would fix both those situations as far as getting air to the carbs... (no cowl to hold in exhaust, and no blockage of air getting to carb... )

As to why it seemed to start this issue after you lost the tilt handle??
Haven't a clue... Coincidence maybe?

Hopefully one of the smart folks here will chime in.. .LOL

 

[jbuote]

Part numbers:

Tilt Handle: 0316082
Tilt Handle Baffle: 0316077

Can try ebay or others... Seems they are no longer available
PM sent by the way..

 

[jbuote]

I looked here on iBoats, and it's NLA here..
A little more searching found this on ebay..
Tilt handle and baffle..

Looks like the right thing to me, but I never had mine off, so I leave that up to you..

https://www.ebay.com/itm/0206525-Joh...EAAOSwvMFa7-Nv

 

[Jconnell43]

Thanks, J Boute, I did go ahead and order this.
Couldn't find it before because I didn't know what to call it

 

[Vic.S]

Thanks, J Boute, I did go ahead and order this.
Couldn't find it before because I didn't know what to call it

If you go to the BRP parts catalog at http://epc.brp.com/Index.aspx?lang=E&s1=9c9c3f04-bb25-461f-94ec-208e7fa0e2ca
you can always find out what parts are called and their part numbers.

On some suppliers websites , which iBoats wont let me name, you can also find prices and availability

The diagrams are very useful too, often almost as good as a manual.

 

[Jconnell43]

Ouch, received above Ebay part and it didn't fit.
Believe it or not the 1971 Johnson 50 and the 1971 Evinrude 50 are not the same part

Am in contact with seller

 

[jbuote]

Ouch INDEED!...
Interesting that seller claimed it's for 71-77 J/E cowls, but then in description (which I missed the first time) says 72-77...
Then lists a part number..
Completely missed that or I may have caught it before posting the link... (sigh..)

The part number listed is for the tilt handle only and you're right..
That's an Evinrude part number.. The baffle (obviously included) is another part number...

DANG!!
Sending a PM.....

 

[racerone]

I might have 1 or 2 of those on the shelf.