3.7LX Mercruiser Closed System/Winterize Question?

[DoctorThunder]

Just picked up a 1990 22ft. walkaround Avalon, made by Raven Boat Co. It has a 3.7LX Mercruiser with a closed cooling system...I changed the oil and filter, no problem....Cannot get to the plugs for the freshwater,sea water or engine block. Am I the only one having this problem? Engine is packed in super tight especially with the heat exchanger...Decided to suck out the antifreeze from the top holding resevour, drain the hoses and drain as much as possible from the heat exchanger with my new handy dandy hand pump ...Put in new 50/50 antifreeze....added fuel conditioner to tank....warmed up engine 5-8 min. with water from the garden hose, shut engine off....hooked up the ol' 5 Gallon bucket full of antifreeze mix...the juice was definately getting sucked in the out drive but didn't seem like hardly any was coming out....ran it for 5-6min....then decided to fog the engine.....ran for a min. or two saw the white smoke from the exhaust and shut down....Did the engine get enough antifreeze from the 5 Gal. bucket? Did I run the engine long enough? Why wasn't antifreeze pouring out of the exhaust? I have a great manual.....when I look at the engine, I just shake my head and think "How can anyone get in there to work on this thing?"

 

[Don S]

Re: 3.7LX Mercruiser Closed System/Winterize Question?

Did the engine get enough antifreeze from the 5 Gal.

How much was left in the bucket?<br />You need to test the antifreeze coming out of the drive to see what the temp is at the end of the run with antifreeze.<br />Did you have the bucket of antifreeze set higher than the water pump in the drive? The impeller can not suck the water out of the bucket, it need a bit of pressure to force it to the pump. <br />If not, you may have cooked your impeller and not gotten AF into your engine.

 

[DoctorThunder]

Re: 3.7LX Mercruiser Closed System/Winterize Question?

the bucket was on top of the boat, about 5-6 ft. above the inlet of the drive....i started with about 4 gallons of antifreeze in the bucket, went half through that, added more then went through about another gallon.....didn't think to test the temperature in the receiving bucket...was too concerned about fogging the engine, was getting worried that my home made 5 gallon bucket was going to blow out the spicket...it was starting to leak...should I restart the engine again, and redo antifreeze...how do I know at this point the seawater part of the engine has antifreeze instead of water? can i pull a hose to check? thanks for the help..........

 

[waterone1@aol.com]

Re: 3.7LX Mercruiser Closed System/Winterize Question?

A few things in your post have me a little concerned, might be issues, might not. You didn't mention what the antifreeze looked like or tested in the heat exchanger, only that you sucked out what you could. You also said that you ran on the hose for 5-8 minutes. The big question here is whether the engine got to operating temperature ?<br /> Just in-case the antifreeze in the exchanger and engine block was watered down or old, etc. You need the engine to reach operating temp, so that the thermostat is open and the new antifreeze that you placed in the heat exchanger has circulated through the engine block.<br />As for the antifreeze that you pumped through the raw water section "hardly comming out" , that is a rough one to comment on without seeing it. I would say that as long as what you saw comming out looked like what you put in, you are probably ok. If it looked watered down, or closer to clear...that would worry me.<br />The five gallon bucket sitting a few feet above the outdrive (on a swim platform or such) just doesn't have the same pressure as a garden house connected to a water faucet. since all "mouse ears" seam to leak anyway, half the time your impeller is sucking air. So it is not unusual for there to be little comming out of the exhaust.<br />I personally use a shop vac that has a pump and garden hose type of outlet (originally designed to empty flooded basements without having to stop and empty shop vac). I made a clear tube that has a valve on it to regulate the output of the shop vac. This thing, with antifreeze in it is as close as you can get to a garden hose for connecting to muffs. In other words, there is pressure at the muffs to make sure the antifreeze gets sucked into the drive.<br />As for the fogging oil, I do not shut the engine off. I steadily increase the flow of oil to the carb untill the engine dies on it's own. Just a few revolutions of the engine while you move from the engine to the key to shutt it off can let the fogging oil be expelled from the cylinders.<br />Not trying to be critical, just adding some observations from what I read in your post.

 

[tommays]

Re: 3.7LX Mercruiser Closed System/Winterize Question?

from everything i have read this year it seams better to remove the stat if your going to store with antifreeze<br /><br />every post with a problem seams to be weather the stat allowed the antifreeze to travel through the block<br /><br />tommays