plugs

[J Headrick]

what is the diffence between lets say a j8c as compared to a j6c...also, in another post you were talking about how any outboard will run fine on muffs, but when you take it out to the lake, it could be a different story...i was wondering if the same applied to a test tank compared to the actual lake.

 

[alcan]

Re: plugs

The differnce in the plugs is heat range. Running in a test tank emulates the lake. The water creates a back presure on the exhaust and a load on the prop. This allows for accurate adjustments. Running on the hose is great for flushing and pre-trip testing.

 

[janichol]

Re: plugs

Another thing I've found is that putting water into the engine through muffs pretty much bypasses the impeller. I just bought a 3 year old Johnson 30 which ran well on the muffs, but would over heat in the water. Impeller was shot... yeah, 3 years in salt water and never had the lower unit cracked.