No compression 70hp

Wfyank

Cadet
Joined
Sep 29, 2010
Messages
17
Hello all been going nuts with this outboard .carbs,coils,starter.went back to starting line did compression test #3 has 0 comp . It had run one time when I first got it. Could reeds be stuck open or am just hoping?any help!!
 

levi_tsk

Ensign
Joined
Dec 26, 2010
Messages
907
Re: No compression 70hp

whered you get your compression gauge? autozone perhaps? theyve apparantly had rash of bad ones lately - go to harbor frieght tools and get one theyre cheaper and they work AWESOME
 

Wfyank

Cadet
Joined
Sep 29, 2010
Messages
17
Re: No compression 70hp

Yes was autozone seems like it's getting good reading whe do other cylinders 110 115 0 I can see piston move freely also but no compression.if it was head gasget wouldn't there be a little movement on gauge?
 

levi_tsk

Ensign
Joined
Dec 26, 2010
Messages
907
Re: No compression 70hp

maybe, maybe not, how about a model number and some background info on the engine please?
 

Sixmark

Master Chief Petty Officer
Joined
Jul 11, 2010
Messages
890
Re: No compression 70hp

Depending on the nature of the problem, a cylinder could very easily show a "0" reading, double check your readings, if still at "0" then it's time to remove the head and do an inspection of the head, pistons, cylinders.
 

Wfyank

Cadet
Joined
Sep 29, 2010
Messages
17
Re: No compression 70hp

Don't have Model # with me right now but got motor 2nd hand shop said comp was low on that same cylinder but feel I'm being taken for ride by this guy trying to figure it out on here.like said I had it out back in spring and ran like champ 2nd time out with wife kids dyes in middle of lake coil cracked .changed out back to lake couldn't make off dock goes into gear then Boggs down burnt out starter.changed it out and noted a frayed wire to temp sencer grounder out.then did compression test.sorry about my typing on here using iphone
 

levi_tsk

Ensign
Joined
Dec 26, 2010
Messages
907
Re: No compression 70hp

i hate to say this but your were told and warned - most guys wouldnt have given you that courtesy ....
how low did he say it was?

nope probably needs to be torn down and rerung and rehoned at the VERY least and depending on the condition of the cylinder when you get the head off you might need an overbore .... triple check your compression readings... but that cylinder is probably wiped out is it on the top or bottom
 

Wfyank

Cadet
Joined
Sep 29, 2010
Messages
17
Re: No compression 70hp

Also looks like heat was Aplyed at one time to top of head could that weekin the head gasget
 

Wfyank

Cadet
Joined
Sep 29, 2010
Messages
17
Re: No compression 70hp

And it ran so think it's something like gasget going anyhow
 

levi_tsk

Ensign
Joined
Dec 26, 2010
Messages
907
Re: No compression 70hp

id have NEVER bought that motor unless it was like 100 bux or less, it was outside the 10% differential when you got it - when your indoubt ask questions here or at a different dealer from the place of purchase most wont steer you wrong i also just for my peace of mind like to do my OWN compression test with MY gauge before i purchase any engine be it in a car or on the back of a boat

unfortunately we live in a day and age where a mans word doesnt mean a damn thing
 

levi_tsk

Ensign
Joined
Dec 26, 2010
Messages
907
Re: No compression 70hp

that cylinder got hot due to lack of cooling a good way to tell if an engine has been over heated is if the paint is flaking off around the head .... you can try pulling the head and replacing the headgasket but BE CAREFUL not to wring off any bolts
if you cant get one to come out fairly easy cut the head of it off and slide the cylinder head off OR better yet cut ALL the heads of the bolts off and heat each bolt with a map gas torch and quench with cold water until fully cool the stubs should come right out then ....

im also VERY weary of fresh paint
 

Wfyank

Cadet
Joined
Sep 29, 2010
Messages
17
Re: No compression 70hp

how on earth does this head come off am i missing hidden bolt? too bolts broke off can they be holding it back.any help feels like im going to crack or worp the head prying on it.
 

Daviet

Fleet Admiral
Joined
Sep 24, 2008
Messages
8,958
Re: No compression 70hp

I think there is about 18 head bolts that you have to remove. If you have some broken bolts, you are going to have to work the head back and forth to get it off. You might end up drilling the bolts out, not a job that I enjoy doing.
 

Wfyank

Cadet
Joined
Sep 29, 2010
Messages
17
Re: No compression 70hp

thanks captain.ones i get it off and new gasket what is tork patern?and do i have to have planed down
 
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