Gud Mornin guys, just wondering if 95 lbs compression is good on my 1973 Johnson 25 hp.And it has a little oil seepage around one of the bolts on exaust cover. Gud or no ? You are some real good people to help us with our problems. Thanks
to low buddy id say u need rings but to check put a few drops of oil in ther if it comes up alot u need rings if no change somthing else is wrong. r both the same if so and it presure stays the same after the oil trick might be a head gaskit
95 lbs should be good, as long as there both within 10%. As far as the oil, maybe a picture would show us better for a good answer. I would think there should just be water in that area. I have had a drip of water, from my exhaust cover on my 87 90HP Johnny for a few years now, and it hasnt got worse, or caused any problems. Im not sure why you would be getting oil from there.
You can try the oil in the cylinders, chances are the compression will come up. You may want to pick up some Deep Creep and spray it in the spark plug holes and let it sit for a day or two. It will loosen up any carbon build up in the rings and on the piston head. Then take it out and run the snot outta it. It will smoke like a house on fire but it will blow alot of carbon out.
Worth a shot.
Well gosh. I would not be concerned at 95 lbs. if, like above comment, they are within 10% of each other. I would be happier if they were 120# but not worried at 95. I did have success on one motor doing a seafoam treatment which brought my compression up about 15#'s on both cylinders. http://forums.iboats.com/showthread.php?p=2648076#post2648076 I also see they made a 73 rope start and if your getting 95 pulling a rope your compression is great. As always a little history and model number helps considerably if it's included with your question. No disrespect to the above posters intended, this is just my opinion. Best of luck. Rick.
Assuming that is 95psi in both cylinders that is excellent. Quit worrying about it.
In a multicylinder 2 stroke the only thing a compression test is good for is to discover if one cylinder is bad for some reason (big difference among cylinders) or there is a gasket blown between cylinders (both read below 40psi).
Compression hypochondria wastes more time and money that all other diagnostic overkill put together.
"Compression hypochondria" JB you made me LOL. I always thought the larger waste of time was the "Oil dripping from my prop How do I change all my gear case seals". Compression IMO is a good thing to document when you get a new to you motor. Rick.
Ok guys this 25hp Johnson 1973 is a pull rope. It runs Great. Has 95 lbs. compression on both cylenders. Model# 25R73A & Ser. # E3783122 . It does not have a starter. If it did it might have more compression.
