New to forum looking for some help with a Yanmar L100v

[MadMax11]

Regardless of topics it is amazing to see so may enthusiast helping out in this case other sailors or to be sailors. Brother has a boat in SC which I have sailed on many times I suspect I may never have enough free time to get my own boat.


I have a question for all the knowledgeable people on this forum. I have a Yanmar L100v that has about 2 hours on it, problem is that the engine seems to have too much compression at TDC for it to turn over via starter (battery fully charged) or by hand. I have used the same starter on another very low hour identical engine and it works fine, decompress decompression lever, hit starter and it fires up as you would expect. the decompression lever works since it will turn over all day long with it on, let it go and as soon as it hits TDC the engine stops. Tried for the heck of it a thicker head gasket, no dice. Valves are adjusted properly (TDC .010), am out of my wits with this one. Hoping someone has run into this before and figured it out. I ended up with the engine as it is so I have no history on it.

[Sailorman97]

Originally Posted by MadMax11

Regardless of topics it is amazing to see so may enthusiast helping out in this case other sailors or to be sailors. Brother has a boat in SC which I have sailed on many times I suspect I may never have enough free time to get my own boat.


I have a question for all the knowledgeable people on this forum. I have a Yanmar L100v that has about 2 hours on it, problem is that the engine seems to have too much compression at TDC for it to turn over via starter (battery fully charged) or by hand. I have used the same starter on another very low hour identical engine and it works fine, decompress decompression lever, hit starter and it fires up as you would expect. the decompression lever works since it will turn over all day long with it on, let it go and as soon as it hits TDC the engine stops. Tried for the heck of it a thicker head gasket, no dice. Valves are adjusted properly (TDC .010), am out of my wits with this one. Hoping someone has run into this before and figured it out. I ended up with the engine as it is so I have no history on it.

You don't say where this is installed. Given the information you have supplied I would look at the wiring on the motor it does not work on. Easy to do. Put the starter on the engine and then direct connect to a known good battery. Short the solenoid and see what happens.

[MadMax11]

Sailorman, thank you for the reply, no wiring involved with the set up, it came from a genset and is on a bench, I am simply jumping the starter solenoid to kick it over. Same way I have with one that I have running. Seems to be mechanical somehow, valves were adjusted at TDC as they should be, and again engine has almost no hours on it. These engines are pretty simple..or should be anyways

[Adelie]

Welcome to CruisersForum!

I would suggest updating your profile with your general location and your boat make & model or “Looking” in the "Boat" category. This info shows up under your UserName in every post in the web view. Many questions are boat and/or location dependent and having these tidbits under your UserName saves answering those questions repeatedly. If you need help setting up your profile then click on this link: https://www.cruisersforum.com/forums...ml#post3308797

I would happily help more if the link above is not enough.