Suspect Cylinder Misfiring - Easy to Change ?

[heraulc2]

We suspect cylinder 1 on our Yanmar 4H3JTE engine is not firing properly because 1) we see a lot of white smoke 2) we're not getting our full RPMs and 3) when testing the cylinder head (unscrew) we do not hear a change in sound on the Yanmar.
We have a spare cylinder. If we want to replace the current one, how easy it it to do?

Thank you

[donradcliffe]

I suspect you are talking about the injector, rather than the cylinder head. Replacing injectors is easy to do, and perhaps one of the Yanmar owners/mechanics can tell you the details of how it is done on that engine.

[sharonwright]

The cylinder head sits on top of your car’s cylinders. It seals the cylinders to form the internal combustion chambers. Cylinder heads are most prone to damage when your car runs too hot or overheats. The trick to extending the life of a cylinder head is to avoid overheating. Again, the best prevention is a regular oil and filter change. This should be met to avoid frequent auto repairs. Therefore, adhere rigidly to a regular maintenance schedule. With that, your engine will start working properly.

[GordMay]

Greetings and welcome aboard the CF, sharonwright.

May we take it that your interest is boating-related?

[lorenzo b]

I think maybe you dropped a valve. Remove the head and take a look. A mechanic will cost you a couple of well spent hundreds right now.