Johnson seahorse 7.5 model AD-11

[Ericschooner1]

I tested the compression on my outboard. The top cylinder is about 10. The bottom cylinder is about 50. I replaced the gaskets and the cylinder head plate where the spark plugs go. I’m not sure what the problem is?

 

[racerone]

Scored piston ?.-----Remove bypass cover.----Look at piston / rings.----Post a picture of what you see.

 

[Ericschooner1]

Scored piston ?.-----Remove bypass cover.----Look at piston / rings.----Post a picture of what you see.

 

[Ericschooner1]

Scored piston ?.-----Remove bypass cover.----Look at piston / rings.----Post a picture

Scored piston ?.-----Remove bypass cover.----Look at piston / rings.----Post a picture of what you see.

of what you see.

 

[Ericschooner1]

Scored piston ?.-----Remove bypass cover.----Look at piston / rings.----Post a picture of what you see.

 

[Ericschooner1]

Scored piston ?.-----Remove bypass cover.----Look at piston / rings.----Post a picture of what you see.

 

[Edchris177]

Are you trying to post a picture? The file has to be under 1mb, resize if larger

 

[Ericschooner1]

Scored piston ?.-----Remove bypass cover.----Look at piston / rings.----Post a picture of what you see.

I tested the compression on my outboard. The top cylinder is about 10. The bottom cylinder is about 50. I replaced the gaskets and the cylinder head plate where the spark plugs go. I’m not sure what the problem is?

 

[Ericschooner1]

Scored piston ?.-----Remove bypass cover.----Look at piston / rings.----Post a picture of what you see.

 

[Ericschooner1]

Scored piston ?.-----Remove bypass cover.----Look at piston / rings.----Post a picture of what you see.

 

[Ericschooner1]

Scored piston ?.-----Remove bypass cover.----Look at piston / rings.----Post a picture of what you see.

 

[Ericschooner1]

Scored piston ?.-----Remove bypass cover.----Look at piston / rings.----Post a picture of what you see.

 

[Ericschooner1]

Scored piston ?.-----Remove bypass cover.----Look at piston / rings.----Post a picture of what you see.

Scored piston ?.-----Remove bypass cover.----Look at piston / rings.----Post a picture of what you see.

 

[racerone]

Did you replace the head gasket before the testing?-----Need to use heat to get broken bolt out.----Show pictures of cylinder walls.----Turn flywheel and look for damage to piston and rings.----Push on rings with small screwdriver ?----Are rings free and springy ?

 

[Ericschooner1]

Did you replace the head gasket before the testing?-----Need to use heat to get broken bolt out.----Show pictures of cylinder walls.----Turn flywheel and look for damage to piston and rings.

I removed the broken bolt. I put on a new gasket and cylinder head plate.

 

[Ericschooner1]

I removed the broken bolt. I put on a new gasket and cylinder head plate.

Did you replace the head gasket before the testing?-----Need to use heat to get broken bolt out.----Show pictures of cylinder walls.----Turn flywheel and look for damage to piston and rings.----Push on rings with small screwdriver ?----Are rings free and springy ?

I turned the flywheel didn’t see any scoring. Didn’t use the screwdriver on the rings. I didn’t want to screw them up.

 

[Ericschooner1]

Did you replace the head gasket before the testing?-----Need to use heat to get broken bolt out.----Show pictures of cylinder walls.----Turn flywheel and look for damage to piston and rings.----Push on rings with small screwdriver ?----Are rings free and springy ?

Did you replace the head gasket before the testing?-----Need to use heat to get broken bolt out.----Show pictures of cylinder walls.----Turn flywheel and look for damage to piston and rings.----Push on rings with small screwdriver ?----Are rings free and springy ?

 

[Ericschooner1]

Did you replace the head gasket before the testing?-----Need to use heat to get broken bolt out.----Show pictures of cylinder walls.----Turn flywheel and look for damage to piston and rings.----Push on rings with small screwdriver ?----Are rings free and springy ?

Did you replace the head gasket before the testing?-----Need to use heat to get broken bolt out.----Show pictures of cylinder walls.----Turn flywheel and look for damage to piston and rings.----Push on rings with small screwdriver ?----Are rings free and springy ?

View attachment 31077

 

[Ericschooner1]

Did you replace the head gasket before the testing?-----Need to use heat to get broken bolt out.----Show pictures of cylinder walls.----Turn flywheel and look for damage to piston and rings.----Push on rings with small screwdriver ?----Are rings free and springy ?

Each cylinder has 3 metals rings. I posted a better picture of 1. They are not soft and playable.

 

[racerone]

Some will argue ----But you will do no damage pushing on rings with a small screwdriver !

 

[Ericschooner1]

Some will argue ----But you will do no damage pushing on rings with a small screwdriver !

It’s made out of metal. Not rubber.

 

[racerone]

???----Good luck with your motor.----I Know evert part in your motor.----Have 3 of them myself !!

 

[Ericschooner1]

???----Good luck with your motor.----I Know evert part in your motor.----Have 3 of them myself !!

If you have 3 then you know each cylinder has 3 metal ring. They are not soft and pliable.

 

[racerone]

Good luck with your motor !!

 

[Ericschooner1]

Good luck with your motor !!

I guess you don’t know that metal can’t be soft and pliable. Thanks for not answering my question. Good day. I’ll find someone that knows motors of the 1950’s.

 

[racerone]

I started repairing outboards in 1968.----Are you working on our first one ??

 

[Ericschooner1]

I started repairing outboards in 1968.----Are you working on our first one ??

It’s a 1957. It has metal rings. I suspect it’s the rings but that’s hard to find. I’m hoping I won’t have to replace it. They look normal no scratches rust and they are hard.

 

[racerone]

I likely have some new piston rings for a 57 model 7.5 HP on a shelf here.----But good luck with your motor.

 

[Ericschooner1]

I likely have some new piston rings for a 57 model 7.5 HP on a shelf here.----But good luck with your motor.

You didn’t even know it was a 1957. But no thanks I’ll pass on those rings.

 

[racerone]

You are funny.----I know that an AD-10 is a 1956 and AD-12 is a 58.----The only 3 years that they marketed those pressure tank 7.5 HP models.-----No more input from me.----Good luck sorting out your motor.