Detecting lean condition

[ted655]

In the thread about "What caused piston to burn", the conclusion was a plugged carb jet.<br />Is there a way of detecting a lean cyldr. before major damage happens? Will a sparkplug reveal anything? Can testing each cyldr. for quanity of fuel, thru the plug hole be performed?<br />Just looking for a preventative, quick check.

 

[DJ]

Re: Detecting lean condition

Ted,<br /><br />The spark plugs will certainly tell a story.<br /><br />Look for differences, on a multi cylinder engine.

 

[Hooty]

Re: Detecting lean condition

Does your engine have choke butterflies or a primer?<br /><br />c/6<br />Hooty

 

[walleyehed]

Re: Detecting lean condition

Look for very light colored ceramic on the plugs...even close to white, indicating a lean condition. They should never be lighter than a medium Tan to light brown.<br />The plugs should also be "slightly" wet-never dry.

 

[ted655]

Re: Detecting lean condition

It is a '84-- 140, I think it has choke butterflys. I;m not experienceing any problems. I just was looking for a way to keep a watchful eye on things. I just changed plugs and all were the same dark color.<br />Thanks

 

[rodbolt]

Re: Detecting lean condition

hello<br /> normally you find a lean out cause it roasted a piston. a symptom is a change in upper RPM's. ie last time it would turn 5400 today only 5000.or it surges or drops RPM at or near wot. that is why I always tell customers that when returning and leaving give it wot for a minute or so. if it attains and maintains wot then back it down to a cruise and hope all the other maint was done.<br /> good luck and keep posting