M25 Blowing smoke at half throttle

Kenneth K

Sustaining Member
Blogs Author
Kenneth thanks for the tip on using the return line for fuel drain. Never thought about it and that's a keeper !

[Thread drift alert]

I should clarify... Disconnecting the fuel return line is a one way to remove fuel from the tank. But, if you're draining the last bits of old fuel from a dirty tank, this is pumping the worst dredges from the bottom of your tank through most of your fuel system. Better in this case to use a separate pump and hose. If not, definitely change all your fuel filters afterwards.
 
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Tom Metzger

Sustaining Partner
I'd sure get a second opinion. Maybe also a third.
Agreed. The first rule of troubleshooting anything is to look at the last thing you touched. You didn't pull the pistons so the rings would be way down the list of things I'd check.. Being an extreme novice with engines I would doubt that the transmission would cause that much load on the engine without making lots of noise and getting hot.
 

Kevin A Wright

Member III
Unfortunately been over those options. Checked the valves twice actually. It's not burning engine oil, but rather blowing lots of black soot out the back leaving rafts of it floating on the water, but no oil slick.
 

Kevin A Wright

Member III
Also no signs of head gasket issues. No oil in coolant or coolant in oil.

Looking at new engines and really like the idea of repowering with a Betamarine 30 to replace the M25 in there. Really like the features and layout of the Beta's, but man they are pricey. Getting a quote of $10,500 for a new one. Any thoughts or suggestions on repower options?

Kevin Wright
E35 Hydro Therapy
 

Kevin A Wright

Member III
Nope, but pretty much have eliminated the tranny as a culprit. Now just looking for a Beta 30 that I can get delivered in the next week or so.

Kevin Wright
E35 Hydro Therapy
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
Nope, but pretty much have eliminated the tranny as a culprit. Now just looking for a Beta 30 that I can get delivered in the next week or so.

Kevin Wright
E35 Hydro Therapy
I notice that you have Sean's former Ericson. Great to see it being maintained and improved!
:)
 

Kevin A Wright

Member III
Yes Loren I do. Got her about 5 years ago and been working on reversing the previous owners decade of benign neglect. Just lots of things reaching 'that age' and needing to be replaced or redone. Made some progress on the interior woodwork last year from dorade leaks but still more to do on that. Now focused on the new engine, which wasn't in the plan. I'm hauling on Tuesday and still working on getting the engine lined up that I want. There's a Beta 30 in California but needs a different tranny, alternator, and control panel than what it has. If they can't modify that one will have to wait 4 to 6 weeks for one to be made up for me.

Kevin Wright
E35 Hydro Therapy (ex O Barquinho)
 
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