Need Advice On Merc 2.0 Rebuild or Reman?

**Capnmoench** · 05-03-2017, 03:09 PM

Thanks. I do have a 2.5L adapter on there now. I bought it as a replacement for my "salted out" corroded adapter that fell apart replacing the mounts and steering arm.

**Capnmoench** · 05-03-2017, 03:11 PM

How cheap is cheap? I still kind of want to get the donor ski boat on the water too.

**rkmirage** · 05-03-2017, 07:53 PM

Originally Posted by Capnmoench

How cheap is cheap? I still kind of want to get the donor ski boat on the water too.

700, it's a clean sweet running engine

**Capnmoench** · 05-04-2017, 01:52 AM

I would be tempted if we didn't have to figure out the logistics of shipping it to Washington state. Also, I'm trying to finish a couple other house remodeling projects and the powerhead swap to the Trophy right now. Then recover from the $3K I dropped on this rebuilt motor. I haven't completely written off the ski boat yet. I told myself it would be worth it to me to restore if I found a motor next to free. You're pretty close. I like that all of the parts on the trim away and everything are the same. It would be nice to have those all as spares.

Originally Posted by rkmirage

700, it's a clean sweet running engine

**Capnmoench** · 05-04-2017, 02:21 AM

Would you suggest replacing the tuner as well? I was hoping to just have to worry about the 10 studs, but i do want her breathing and cooling right.

Originally Posted by rkmirage

You will have to change the adapter.

**Capnmoench** · 05-04-2017, 03:24 PM

Ok. I just did a serial number check. This is the same series as my last motor. Everything is the same part number down to the exhaust adapter, gaskets and tuner. The only questionable item is the tuner is listed as a different part for 150 (jet). I'm thinking this is only for the jet version though. Check me on it. Serial of the old 150 is 0G089..can't remember the rest and the new 175 is 0G042476. Looks like a direct swap.

Originally Posted by Capnmoench

Would you suggest replacing the tuner as well? I was hoping to just have to worry about the 10 studs, but i do want her breathing and cooling right.

**Capnmoench** · 05-22-2017, 12:11 AM

OK, So, I got my blown powerhead ripped off the leg. I noticed that the exhaust "galleries" are dry as bone. No soot, no coking. Is this not right. I did only have it out 5 times after I got it going, and it's been sitting since October, but I would think a 2-stroke would have an oily sheen in the exhaust passages. I cleaned up the adapter from the new-to-me 175, and there was tons of gunk in there. I could almost use the 150 as a bowl for soup it was so clean.

Thoughts?

**W2F a V-King** · 05-22-2017, 07:20 AM

Maybe that motor was running properly. Good oil mix ratio. Good air to fuel ratio...properly tuned.

What did the piston wash look like? Sooty and coked up is a sign these are not correct. imo.

**Capnmoench** · 05-22-2017, 10:09 AM

It was slightly damp. No sheen or wetness, just a thin coat of carbon and damp. Maybe it was running properly. I'm just a bit paranoid after all of the issues. I smoked good at idle. It would irritate you with the bimini up and no breeze to clear the deck while plowing at no wake speeds. I would have to open the wing windows.

Originally Posted by W2F a V-King

Maybe that motor was running properly. Good oil mix ratio. Good air to fuel ratio...properly tuned.

What did the piston wash look like? Sooty and coked up is a sign these are not correct. imo.

**Capnmoench** · 05-22-2017, 10:24 AM

Looking further, and researching piston wash, I think it may have been too lean, but not bad. I took some additional photos. It's hard to tell because of the slight rust from sitting, but with the flash on it reveals the original surface.

Originally Posted by Capnmoench

It was slightly damp. No sheen or wetness, just a thin coat of carbon and damp. Maybe it was running properly. I'm just a bit paranoid after all of the issues. I smoked good at idle. It would irritate you with the bimini up and no breeze to clear the deck while plowing at no wake speeds. I would have to open the wing windows.

**W2F a V-King** · 05-22-2017, 03:52 PM

Yes, cyl #1 has a problem. The others, maybe a fuzz lean, but not by much.

**Capnmoench** · 05-22-2017, 04:10 PM

Cool. I thought they looked ok. Yeah, # 1 definitely has an issue, but we new this. The other motor is running pretty rich then. The guy was running premix with injection though. He's only run it twice. Maybe it wasn't completely cleaned out when the powerhead was installed.

Originally Posted by W2F a V-King

Yes, cyl #1 has a problem. The others, maybe a fuzz lean, but not by much.

**Capnmoench** · 08-21-2017, 09:26 PM

So I disassembled the 150. I couldn't see a problem with the thermostat. There was a crust "flap" on each of the water intake holes on the heads, but nothing I could say would obstruct flow too much. For a 500 hour motor, it has an awful lot of cross hatch marks on the cylinder walls I think. There are a lot of messed up rings. I don't know if it was a problem it was having or if it happened after cylinder 1 took a crap. I'll post the pics and you please tell me if you can see any tell-tale signs of what happened.

**nitro_rat** · 08-25-2017, 06:48 PM

I'm often tempted to clean the aluminum junk out of the cylinders on a 2.0 (muriatic acid works well) and dingle ball hone it, then stuff in another piston. #1 in the 175 on my motor was done this way, it has about 5 lbs less compression than the other 5, but I don't notice that while screaming at 7200 for extended periods...

I don't know if that method is trex approved, but it's saved me on machine work in the past.

I will vouch for James Perry's work though, he's not a hack like me! PM me if you would like contact info.

**Fishinmymission** · 08-28-2017, 05:54 PM

Doesn't the exhaust port look more grey and less oily/sooty on your number 1(bottom right in the picture showing all 6)? Makes me think it was running leaner but not certain if the discoloration is a symptom of running leaner or a result of piston failure. I also can only see the pictures you just posted all the old ones are no longer visible.