Towed my jeep from Maryland to Ohio yesterday. It's been about 5 degrees the whole way. Started her up this morning to back off the trailer and heard funny screeching noises and saw steam. Belt had come off and coolant was draining down the back of the block from somewhere I can't see (coolant reservoir was frozen solid, I guess my ratio was off apparently :/ ) Oil was chocolate milky colored on dipstick. Do we think it's a cracked block or freeze plug? Thanks y'all.

 

Sorry to hear that. I might drain the oil and see how much water is in there. A compression test might be high on my list. (EDIT; before pulling the head) There are freeze plugs on the back of the head/engine. (and the left side) Water in the oil of course can be a head gasket issue, but in this case.....Also see if the level on the dipstick is high.

 

x2 to DF. I would drain oil and see what there is to see then locate and replace freeze plugs. Maybe leave the oil drain plug out while refilling with coolant if you think you possibly cracked something internal, if coolant comes running out you'll know it's toast. Hope it's not too bad!

 

Engine coolant frozen solid. For some reason the block or head will often crack before the freeze plug gets pushed out.

Chocolate milk for oil means coolant is definitely in there. Freeze plugs don't have any connection to the oil passages.

 

Thanks for feedback. I'm assuming the worse case has happened. Going to test it just to be sure over the weekend when it gets into the 40s with a compression tester. I'll update with what we find. May be looking for a 350 in the near future

 

Yer funny! But I did put a 350 in my Jag. The inline 6 4.0 is a supper engine, I'd just get another block from the JY, maybe, if I were you. You would have "an ocean of fun" doing that conversion and passing smog....

 

Geeze ! That's sad, and a hard learned lesson too......

I've done rebuilds & replacements on marine engines that didn't get winterized in time. Same type damage....

 

I have an inline 240 six in a 66 Ford F-250. (same block as the 300, but with a different crank) I got a factory short block from some old drunks at a muddy JY on Dec. 31, for $75, with a fork lift hole in the pan. (they just wanted booz $ for New Years!). (Fushey Brothers, off Dutton in Santa Rosa CA, mid 80's) Went ahead and did ring's and rods in the back of a buddies truck.

Later I drained the water cuz I knew it would freeze. Left a cup in there behind #6 I guess. Cost of repair? 57 cents. I made a tripod with trees here, got a buddy to help, and with a cheapo 2 ton come-along got it in one day. (the freeze plug was under the flywheel, which is of course behind the transmission)

Interesting lesson in the reality of things...It took me about 1/2 as long to get the stupid solonoid wire on the starter right. I forget the details, but the thread, the nut...RRRRR Btw I still have it here and it runs smooth as butter, and has been on the scale at the rock pit with just under 10,000 LBS gross weight. (That's with me, the dog, and the toolbox)

 

Big dog.

 

That makes me glad I live in Arizona. It was 74 today and sunny

 

Ya, but you never get to drive on your lakes

 

That's why I own a boat.

 

Actually, last I knew Mich was second only to Fla for number of reg boats.

 

Freeze plugs blowing won't water the oil, there's no connection there so it probably cracked the block or the head.

Minnesota has the most boats per capita with close to 17% of the population being boat owners vs. Florida with only about 5% boat ownership. As far as total number of registered boats the numbers are tight between the top 4 with Ca. being number one at over 1 million, then-Michigan, Florida, Minnesota. Registration requirements for boats vary from state to state so the numbers will be a bit skewed.

 

Well, upon further inspection today one of the rear freeze plugs is completely gone with no trace of it nearby. Maybe it popped during transit? Checked oil a couple times and looked fine. Maybe it was just a little discolored on first inspection? From repeated short start ups or fluke? I poured about a gallon of water into reservoir and all came rushing out the back of the motor and I found none going into the oil or rise in oil level at all. Maybe it needs pressure to get through a crack? Starting to think I may have overestimated the damage..hopefully!