Yanmar 1GM Cup Plug Popped Out

[SailormanDan]

Hi,

I am in the process of troubleshooting an overheating Yanmar 1GM engine. I took the zinc out and was reaming out the cooling passages with a nylon bottle brush and somehow popped out the cup plug on the front of the engine. I carefully tapped it back in place, but read afterward in the service manual that I should have put some sealant on it before re-seating it.

Now I'm not sure if I can get it back out, I'll pull the zinc and try, but if I can't get it out easily, am I stuck with waiting until it pops out randomly and hope I'll figure it out before it causes too much damage? When I finally run the engine and let it idle at the dock to ensure the buzzer doesn't sound, will the heat loosen it so it might pop out while I'm at the dock with the engine open and be able to quickly shut it down?

Thanks, in advance for any help you can give me. Or prayers ;-)
Dan

 

[Ted]

You can remove it by drilling a hole in the center of the freeze out plug and then screwing a siide hammer into it. A couple of rape should free it easily especially since it's been out already. Fix it right and fix it now before you do serious damage later. Problems seem to happen at the most inopportune times. It looks like it's been leaking in the past.

 

[SailormanDan]

"Fix it right and fix it now before you do serious damage later."

Now that you point out the rust from prior leakage, you're right Ted, I should make the effort and fix it now. It's never something simple is it?

 

[Bill Roosa]

Freeze out plugs should never be reused. The new ones have a slightly beveled edge that gets bent upon instlation. This is important to make sure it does not blow out when the pressure gets up to specs. if you reuse the old one you are asking for a major emotional event in the engine compartment with scalding water being unpressurized at a rapid rate resulting in MASSIVE amounts of steam...... Very hard to brief this as "it's ok honney I know what I'm doing"
They come in standard sizes at the auto parts store. Cost like $3

 

[SailormanDan]

Thanks, Bill, I hadn't realized they were single use only. I had to order some other parts from Torresen Marine, I'll get them to send me the right one.

Hopefully getting the old one out won't make the problem worse, the way my luck is going.

 

[Bill Roosa]

While you have it out you can do additional cleaning of the inside of the block.. yea!

 

[SailormanDan]

<oops!> That's what I was doing when the plug popped out. Keeping my fingers crossed all this fixes it.