69 Johnson 9.5 low compression.. Will it start?

[brtc]

Just inherited a 9.5 johnson. I rebuilt the lower unit, cleaned up the old head gasket (new one on order now), changed spark plugs, and cleaned the carb. I tried to start it and got nothing. So i went to auto zone and got a compression gauge and it's pulling 50 psi in one cylinder and 60 psi in the other. I know it should be around 80 to 90. . I have pulled and pulled on this thing and get nothing. Is it possible to start it that low? What do I need to replace? I assume the culprit is the piston rings, just hoping there could be something else. It was holding pressure in both cylinders, it was just low. Thanks for the advice..
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Also, this could sound dumb, but when i was replacing the impeller, I noticed that the drive shaft rotates counter clockwise, so i placed the impeller so it would rotate counter clockwise. Makes sense. on http://www.**********/parts/search/BRP/JOHNSON/1969/9R69S/GEARCASE GROUP/parts.html, (place boats dot net in place of stars) it shows a breakdown and the impeller looks like it rotates clockwise? is this just a poor drawing, or am i missing something?

 

[nwcove]

Re: 69 Johnson 9.5 low compression.. Will it start?

dont panic yet, reusing a head gasket could be the culprit for the low compression, but even with the low numbers it should make an attempt to start.( depending on the guage you bought, "holding compression" can be done by the guage alone ie...it can be removed and still hold its last reading until you release the pressure) try putting a few drops of premix directly into each plug hole. you do have spark??
as far as the impeller goes, the vanes should always be in a "trailing" position relative to the rotation of the engine.

 

[kfa4303]

Re: 69 Johnson 9.5 low compression.. Will it start?

Hi brtc. Did you test the compression before you removed the head gasket? Without the headgasket properly installed you won't get good (if any) compression. Believe it or not, 60 psi isn't too bad and may go up once the motor has warmed up. You can also do a decarb procedure using Seafoam, or similar product which shuold also help. As for the driveshaft, it should only ever spin clockwise. You'll need to reinstall the impeller accordingly. Here's a parts catalog with exploded diagrams of your motor. You can get any routine parts like carb kits, points & condensers, head gaskets, etc... right here at iboats. Be sure you only ever run the motor in a test tank with water filled up to about and inch below the main exhaust port. These old motors can't be run on muffs. You'll also want to run at least 50:1 fuel oil mix (I like to be safe and run 24:1) with Champion J4C plugs. Here are some handy links.

http://www.leeroysramblings.com/OMC_9.5.htm

http://www.marineengine.com/parts/johnson-evinrude-parts.php?year=1969&hp=9.5&model=9R69S