View Full Version : 2006 maristar freezeplug and milky oil help

05-08-2011, 10:03 PM
First off, I am new on here. I have tried to search and have found some results, but still leave me close to clueless.

I have a 2006 maristar with the 5.7l ~310hp motor. Last winter I winterized it like I always have. I let the water drain from the plugs on the side, the hoses, pulled the impeller completely out and left the pump open (no cover). I left the lower hoses that would all let gravity pull dripping water off or un buttoned. Well, I put impeller back in and put all the hoses back on about three weeks ago. Have since had HORRIBLE rains here in Arkansas since I did this, the boat has been outside but completely covered by the OEM cover and a tarp over that. I went today to put it in the local river just to let it run for a little while and change the boards on the trailer because they are getting pretty bad. Well I let it run on the trailer till it gets to running temp every year when I first put it in the water to check everythign is ok.... Today it wasnt.

First I noticed water was pouring the in boat from the motor, found two of the freeze plugs have come out sometime (I didn't notice them when I was dewinterizing, but that does not mean they were not already out) and water was pouring in the boat through these holes. I let it run maybe a max 5-8 minutes before I found the issue. So I pull back up the ramp and start playing with it and find its the freeze plugs. It is the two inside the motor mounts, so it is not easily accessible.

Then I start checking more things and find the oil full of water, I mean coffee with more creamer than coffee. I know the oil needed to be changed every year, i normally replace it beginning and middle of summer. But I wasn't even going to do more than let the boat idle today, just to replce the trailer boards.

So, first question, Can these freeze plugs be put back in without lifting motor? I know something caused them to pop, maybe the real hard winter Arkansas had, or I did a less than ok winterization, or I dont know.

#2) Any suggestions on the oil from question 1 and other problem, or are these definitely two seperate problems?

#3) I will be running a compression test and leak down test as soon as I can. Do these freeze plugs need be installed back in the block before I can put a definite yes or no to any further damage?

#4) Any help will be much appreciated, I am not the most mechanically inclined, but I am not the dumbest either. I will attempt anything anyone posts to help and know a fair amount about motors (Have built a few lq9's for performance trucks, also ls1's).

So thanks in advance, and I'll check this as often as I can because lake time is here, well maybe not for me if I am destroyed my motor.

05-09-2011, 12:10 AM
Damn dude, that sucks! You didn't winterize it wrong, same thing I do every year and while my boat sits in a garage all winter,I've had them outside briefly (days, not hours) in colder temps than Arkasas gets without issue.
Just popping the freeze plugs wouldn't cause water in the oil. EIther something's cracked (block, head, manifold(?)) or water got high enough when it was runniingto get into the engine somehow, like the bottom of the dipstick, which is unlikely as well since I had my 190 LT-1 boat filled with water up past the floor boards in a rainstorm with no water in the engine.
Maybe the block was packed with sediment towards the bottom and kept the water from getting out the bottom holes, but you'd have noticed that when draining the engine I'd think.
You'll have to pull the engine to get the plugs in behind the mounts unless there's some way to carefully pry NEW ones in.
Sorry I don't have more suggestions.