Winterizing plugs and oil questions

[danzee]

I have a "new" 1978 boat with raw water cooled A4. It's the original motor from what I can tell.
I've read Don's Winterizing summary and have some questions:

1. It appears the MMO alone is meant to be left in over the winter, with no new oil added. Do I have that right, and should remove the MMO first before adding the new oil in the spring (I have no history on previous changes).

2. I'm going to change the spark plugs. Should I do that after I squirt in the MMO in to fog the engine, or should I put in the old ones and swap for new in the spring? I ask because I wonder if the plugs will be fouled with the MMO.

3. I noticed someone mentioned he has no thermostat in his A4. Was that a "feature" on some engines or a mod? Is it a good idea? My experience says the engine would never reach operating temperature that way (i.e. bad idea).

[sastanley]

danzee..fear not. You'll get lots of responses. Here's how i've done it myself as a relative A-4 newbie.

I do the MMO in the crankcase before the oil change. Then I drain and add the fresh oil in the crankcase so it's ready for next season.

I would also 'fog' the motor with old plugs..I'd install the new plugs to seal the combustion chamber, ready to fire up in the spring.

Dave Neptune has run his motor with no thermostat forever. Most of us have a t-stat in ours. With a raw water cooled motor, you want to pinch off the hose just before the the t-stat when sucking in pink RV antifreeze to get as much into the block as possible..otherwise, unless the t-stat is open, a large portion goes over the closed t-stat right into the manifold...skipping the block..squeezing off the hose forces the antifreeze (via the sideplate "tee" under the alternator) into the block first on its way to the manifold.

By the way - Use the drain plugs to drain the block first too..

[danzee]

Thanks. That all makes sense, but I figured I'd ask. I had planned to remove the thermostat to insure I got all the passages. Perhaps I'll just pinch.
But (there's always a but) . . .
Is the use of pink "RV" antifreeze rather than automotive type(s) recommended for environmental concerns, or another reason?

[Baltimore Sailor]

It's environmental. The pink RV antifreeze breaks down naturally and isn't toxic.

[sastanley]

re-reading my reply, I guess you could pull the thermostat to keep from 'forcing' antifreeze thru the t-stat and helping to make sure the block is flooded with antifreeze...the water pump would probably suck it in a lot faster too without the t-stat restriction...maybe i am just lazy (removing the t-stat and possibly screwing up the gasket)

Maybe this year I might try it without the t-stat and see how it goes..I also don't think I had the bypass kit installed last year (same effect as pinching the hose prior to t-stat) to make sure I 100% cut off the supply over the t-stat forcing all the antifreeze in the block.

[ArtJ]

Even if the Thermostat is removed, it is still recommended to pinch(block off
the bypass hose in order to force all flow thru the block.

Regards

[Dave Neptune]

No T-stat

Hi guys thought I'd chime in here. I have run successfully without a t-stat for 26 years. My boat is run in So. Cal waters and the temp varies between 55 ~ 70 degrees. Once I have the "3/8" ball valve set I don't touch until it starts to run over 140 which is about as high as I run it. I cruise at 2000 rpm's with the Indigo prop towing a rowing skiff most of the time. The temp varies from about 125 ~ 135 depending on the time of year.
When I have to close the valve a bit more every couple of years (I start about half closed 45 degrees or so) and then the fourth time I usually do an acid flush with an auxilluary pump from work. I warm the engine~drain~unhook line from A-4 water pump & hook to pump in 5 gallon bucket with acid solution~disconnect exit line from manifold and attach longer hose ~ run into bucket~turn on pump wait 20 minutes~shut off pump. You would be suprised at how much KRAP accumilates in the bucket, Then begin flush procedure. Fin
I like being able to adjust my temp although I have chosen to run it cooler as it sits in the cabin under the setee. It get the setee very hot. My wife and daughter who sleep on it like how it warms up for sleeping and so does the Giz.

Dave Neptune

[sastanley]

Hi dave & art...thanks for clarifying on the 'hose pinch' to force water into the block..

[Jesse Delanoy]

When I winterize, about this time of year each year, I remove the thermostat and disconnect the bypass hose from the thermostat housing. I plug the loose end of the hose (using a metal end-fitting inserted into the hose, secured with a hose clamp, and closed off with a screw-on cap), and insert a pipe plug into the open hole in the thermostat housing. This way, I ensure all the antifreeze goes through the block, and I take the thermostat home to give it a vinegar soak, and store it until the following spring.

I have run the engine from time to time (all season once, on the advice of a mechanic) in this configuration, with no thermostat, and it does run fine, but it runs very cool.

I keep thinking about leaving it out, and adopting Dave's idea of using a ball valve in the hose where the raw water leaves the rear of the manifold, to control engine temperature. I'd probably run it hotter than he does, so maybe I could use the hot engine water to heat my hot water heater tank.

When I fog the engine with Mystery Oil, I replace the old spark plugs, and, as Don suggests, run for about 30 more seconds to spread the MMO around the valves and upper cylinders. I leave the old plugs in, and replace with new in the spring, as the engine usually won't start in the spring with the old, MMO-fouled spark plugs.

[Dave Neptune]

Correction!!!

Jesse, my ball valve is on the bypass line from the diverter to the T-stat housing NOT on the manifold. The manifold would restrict the total flow not the amount diverted while maintaining full flow~~important!

Dave Neptune

[Jesse Delanoy]

Dave, sorry, maybe it wasn't you.

I could swear I read a post on here, a while back, with someone who runs with no thermostat (tending to make the engine run cold, as I have experienced in the past), but who has a ball valve at the exit from his manifold (constricting the entire flow, as you pointed out), which he can set to warm up the engine to whatever temperature he desires.

This concept has intrigued me, as every other setup I try, to use hot engine water to heat my hot water heater tank, tends to make the engine run too hot.

Your version makes the engine run cold, and then by closing your bypass valve, makes it run colder. However, that seems to satisfy you. I'd like to get mine to run about 170 WITH the water passing through the water heater core, but it nominally runs 170 - 180 WITHOUT the water passing through the water heater core, and always has (unless I pull the thermostat, as described above, in which case it runs down around 130 or so).

Jesse Delanoy
1977 Catalina 30 "Off The Grid"
Baltimore/Pasadena, MD

[hanleyclifford]

running no thermostat

Jesse - If you have a raw water cooled engine and you want to run a heater with engine water and you want to run with no thermostat here is a suggestion: from the exit fitting on the manifold go direct to the heater input side. Then from the heater output go to a diverter valve which selects between the injection point on the hot section and the input side of the water pump. Of course there will be a minimum value required for the exhaust cooling. I do not think it is a good idea to "deadhead" the manifold exit port due to clogging issues in the castings. It may also be necessary to restrict raw water entering from the thru hull. Hanley