Unseized Yanmar 2ym15 no compression

[Mike Banks]

Stuck valves would be my guess. Pull off rocjer cover, spray them with CRC and tap gently on tappet with hammer on wooden block, until they free up. While at it, replace the valve stem seals.

[skipperpete]

Originally Posted by bouncycastle

Thanks for all the info on air pressure bar and compression lever and cheaper sources for test kit to test compression

If I remove engine to work on it this season I would have to park it some place for few months and opt to get a outboard motor to keep me going this season . I would only remove engine if I knew it was piston ring issues because in that case if I cut the cockpit floor I can access the head and valves if they are the issue




What gets me is why did the engine seize up after two years to be not used where as in 2019 when I bought the boat the engines fired up no issues after it had sat in the boat yard for five years and never even been serviced or used in five year s


I hope to try to make able to make. a devise that can extract
the injector seals

Also I will try to make a devise that can replace the injector and attach a balloon type device to it and then turn over motor and if balloon fills and deflates that could tell me if the pistons are pumping and the valves are closing .

Even if I order a compression tester from Amazon it could take weeks to get to Ireland as the USA slides rapidly into
a severe fuel crisis and supply chain crisis because they send all their oil to Europe and Ukraine to fight the Russian war

The latest Practical Boat User Magazine has a main article on engine crisis either to buy or sell or repair a broken engine .

It seems that he Kaboda engine has no electronics and might be the best buy for blue water sailors with so many stranded waiting for electronic control systems

Hi Bouncycastle, I just took a glance at your own previous thread where you describe several worrying incidents with that little engine including its massive oil leak and the later engine flooding and suspected hydrolocking and I would suggest its time to get that engine out and into a place where it can be stripped and assessed for rebuild. An engine thats sat for a long period of time AFTER a crankcase flooding will likely have considerable internal corrosion leading to a prohibitively expensive repair.
Good luck with it though, I hope it looks ok when you get the rocker cover off.
Pete