Loss of compression?

[Dusky203]

I have a 1993 175hp spitfire evinrude. My mech. found two cylinders with pretty low compression. I do not remember how low but my question is this:<br />The motor last time out seem to loose power to about half of the cyliners. Leading me to belive there is an electrical issue with the ignition system. Could the lack of compression cause this or could I evaluate the ignition system for some temporary relief until I can afford a new motor? The wierd thing is after letting the motor cool down she would run fine for about ten minutes then loose powere again. What do you guys think?????<br /><br /><br />Tim

 

[danny k]

Re: Loss of compression?

A loss of compression is normally caused by stuck or broken piston rings, or a scarred cylinder wall, or a combination of any of the above. Chances are the cylinders in question are still firing, but with loss of compression comes loss of power. Don't confuse the loss of compression with an electrical problem. If the cylinders are not firing is a problem in and of itself and has no relationship to loss of compression. If they are firing the engine will run better then if they are not firing but still, with low compression, your power will be reduced.<br /><br />Has this engine overheated?<br /><br />Danny K.

 

[Dusky203]

Re: Loss of compression?

It has not overheated unless my temp gauge is broken. I am very good about keeping and eye on this but sometimes you never know. I do feel like what I am experiancing is ignition failure of some sort. I kind of ruled out the compression thing due to it running fine after a slight cool down but I could be wrong on that assumption

 

[rodbolt]

Re: Loss of compression?

compression is a mechanical function. mechanical things dont come and go, they may get worse but not come and go. post the numbers the tech found.

 

[REELSPORT]

Re: Loss of compression?

you may be losing compression after engine warm up thus you have power loss. you may want to try and do a decarb with seafoam and if you have a stuck ring it will more than likely break it loose. good luck