4hp outboard exhaust cover gets very hot

[Psycon]

Hey all.
My 1996 4hp Johnson outboard exhaust cover gets very hot. I ran it in the tub today to check for over heating and the cylinder heads you can touch and hold your fingers there for about 5-10 secs before they feel hot. The exhaust cover you cant really touch as it is so hot. The side where the cooling water runs feels cooler but you cant hold your finger there for more than 2 secs or so. I did pop the cover off after giving it a quick run in water but the channel looked dry (although the warmth of the exhaust area may have dried it out), and when I flushed water through the top and bottom hole in the inlet and outlet of the water channel, the water came out of the exhaust and there didn't seem to be any blockages. I am guessing these plates do get hot as it's where all the exhaust gasses pass through. If you also splashed water on the plate it didn't bubble but dried up and steamed a bit. Is this normal?
Thanks

 

[[159032]]

Is it like this '83 (Evinrude) version. Evinrude '83 4hp EXHAUST MANF. HOT AS HECK Page: 1 - iboats Boating Forums | 627733

The grommet they refer to can swell up and block the water flow. It looks a bit like a horses arse when it does that.

Item 50 on this diagram. Johnson Midsection Parts for 1996 4hp J4REDS Outboard Motor

 

[claymore]

Are you suggesting that horses wee through their bottoms?

 

[[159032]]

You just cannot trust horses.

 

[VicS]

Hey all.
My 1996 4hp Johnson outboard exhaust cover gets very hot. I ran it in the tub today to check for over heating and the cylinder heads you can touch and hold your fingers there for about 5-10 secs before they feel hot. The exhaust cover you cant really touch as it is so hot. The side where the cooling water runs feels cooler but you cant hold your finger there for more than 2 secs or so. I did pop the cover off after giving it a quick run in water but the channel looked dry (although the warmth of the exhaust area may have dried it out), and when I flushed water through the top and bottom hole in the inlet and outlet of the water channel, the water came out of the exhaust and there didn't seem to be any blockages. I am guessing these plates do get hot as it's where all the exhaust gasses pass through. If you also splashed water on the plate it didn't bubble but dried up and steamed a bit. Is this normal?
Thanks

The exhaust cover on the 4 hp Johnsons is just a plain plate with exhaust gas on the inside ... therefor it gets very hot.

The engine's larger cousins have a additional water cooled outer exhaust cover, #27 in the diagram below, which remains relatively cool. ( #32 are gaskets, #29 is the inner cover , #37 and#20 are the telltale, which you dont have on a 4 hp.)

 

[Psycon]

Is it like this '83 (Evinrude) version. Evinrude '83 4hp EXHAUST MANF. HOT AS HECK Page: 1 - iboats Boating Forums | 627733

The grommet they refer to can swell up and block the water flow. It looks a bit like a horses arse when it does that.

Item 50 on this diagram. Johnson Midsection Parts for 1996 4hp J4REDS Outboard Motor

If this was the case wouldn't the tell tale stream be more like droplets rather than a stream?

 

[Psycon]

The exhaust cover on the 4 hp Johnsons is just a plain plate with exhaust gas on the inside ... therefor it gets very hot.

The engine's larger cousins have a additional water cooled outer exhaust cover, #27 in the diagram below, which remains relatively cool. ( #32 are gaskets, #29 is the inner cover , #37 and#20 are the telltale, which you dont have on a 4 hp.)

View attachment 92981

 

[Psycon]

Ok so it looks like the plate getting really hot is normal then. That's a relief thanks ?