ZR4 Winterizing: Trouble draining 2 items

[paticus]

This is my first winter with the 2019 Nautique 230. So, getting to know the PCM ZR4 6.0. I was able to drain 5/7 areas, according to the manual (attached). I’m having trouble with items:

#1 Removing inlet hose from raw water pump
#5 Removing drain plug from transmission oil cooler

The raw water pump is shoved way back and under the rear of the engine (stern), I don’t see how I can possibly get access back there without pulling a bunch of stuff off the back of the motor. I can barely feel for the hose clamp let alone loosen it and pull the hose (and put it back!)

The transmission oil cooler doesn’t appear to have a drain plug. I’m guessing removing the inlet connection will suffice? Or am I overlooking something?

[NautiqueJeff]

On the trans cooler, just pull the hose. That's what most people do instead of trying to get to the tiny little drain anyway.

On the water pump, not sure what to tell you there. I doubt you'd get anything out of there anyway, especially from the intake side. I would maybe consider spinning the engine over for a second or two to pull any remaining water in the pump down into the engine, where it can drain out of the already open drains, and call it good.

Are you planning to run anti-freeze through the engine, or just leave it dry? If you're going to pull anti-freeze through it, I would be even less concerned about that little bit of water that may be in the raw water pump. That'll definitely get flushed out with anti-freeze if you use it.

[Infinity]

On my ZR409....I do exactly like Jeff said. I drain everything EXCEPT the 2 items you mentioned in your post and then suck in anti-freeze (I do it for the corrosion protection since it flushes out any residual small amounts of water).

My engine is partial closed cooled which includes the heater....but I believe that the ZR4 does not have that. So if you have not already, be sure to blow out your heater lines if you have that option. Typically the heater core would be the 1st thing to freeze.

[bturner]

Same as above but I fill "old school" by pulling the heater hose on the top of the engine block and one of the hoses on the thermostat housing. I fill from the heater core port on the engine block and pour until antifreeze is coming out the thermostat housing. At that point simple fluid dynamics dictates that the antifreeze has reached that level throughout the block. I then very briefly start/run the engine, maybe 5 seconds. This gives the antifreeze just enough time to circulate antifreeze without it all running out the exhaust. Been doing it this way for at least 20 years with zero failures.

Agree also on the trans cooler. Pull hose and forget screwing around with a tiny plug. I'll also feel around the inlet side of the cooler to make sure no seaweed made it past the strainer and is possibly plugging the honeycomb element in the cooler.

[paticus]

Thanks for the replies and tips, I’ll pull the hose at the trans cooler and probably run through some antifreeze as well.


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[Evening Shade]

Thanks for the replies and tips, I’ll pull the hose at the trans cooler and probably run through some antifreeze as well.


Sent from my iPhone using PLT Nautique

This is exactly what I do with my ZR4. Pulling the hose from the tranny cooler lets the water drain. I don't worry about any little bit if water in the water pump because it gets flushed out with AF.

[ngs20]

when you pull the hose of the transmission cooler Uncategorized Groups it looks like it is just below the Home raw water outlet hose. wouldnt that be sufficient?

[bturner]

I would agree, it should be. I never pull the hose off the raw water pump.