Compression check of cylinders

[brett985]

Compression check- What PSI would be an ideal reading from the cylinders on my 1998 Johnson Oceanrunner 90hp?

The motor has 360hrs of normal recreational use.

[antonywardle]

The most important thing is that they are all similar numbers.

That said, from memory, my old Evinrude 90 from a similar age were

all around 115, except for one that was 30.

[brett985]

I guess thats why its the old one. What did you upgrade to?

[antonywardle]

Etec 90HP 2009 or 2010 model

Yes, thats why I upgraded, although if I had have taken the engine to the shop that I currently use

I'd have saved myself a packet. I hear that the ocean runner engines are pretty good though

I sent you a PM too.

cheers

[shakey55]

About 8 months ago I bought a new boat (new to me) which had a 2000 model Johnson 115 two stroke (Oceanpro).

When I did the compression test all cylinders were around 125.

Hope this helps

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[Sigma]

About 8 months ago I bought a new boat (new to me) which had a 2000 model Johnson 115 two stroke (Oceanpro).

When I did the compression test all cylinders were around 125.

Hope this helps

Sent from my iPad using Tapatalk

Thanks Shakey55.

I was just wondering what the compression should be for my motor, and bam....you post it up.

I have the same motor as you, a Johnson 2000, 115Hp two stroke Ocean Pro.

I have 480 hrs on mine but 435 of them have been used in fresh water from the previous owner.

Would love to get some feedback from someone like yourself who has the same motor.

Couple of questions as I'm not familiar with these outboards.

Does your Ocean Pro blow a bit of smoke when the muffs are on?

Also, does she idle a bit rough (not too much though)?

I've taken it to my mechanic and he reckons that it's quite normal as the two strokes usually idle more roughly than a 4 stroke....I'm just not convinced though.

[brett985]

Which oil do you use?

It should idle ok but yes an older tech 2 stroke outboard will have the occassional shudder and cough. A bit of smoke on the muffs is normal. You can see it easier as there is no lake/sea water covering up the smoke.

[brett985]

At one point i tried running caltex vortex 98 and BRP xd100 synthetic two stroke oil. Ran smooth and smoke free.

Too expensive tho at a $riddiculous for fuel and $80 for oil.

[Sigma]

Yeah, that's what I get...shudder and cough. So, looks like they're all the same.

I'm not sure (can't remember now) on the oil but I will check when I get home.

It's a brand name like Penrite or something similar, it cost me $50 for 4ltrs.

My mechanic told me that Johnson's are very sensitive and that I shouldn't use anything bar Vortex 98.

So, I use 98 now and he's quit right, it runs much smoother than it use to......but it can be expensive at the bowser.