I think she cooked it ! 318 @ 300 + degrees

[jprather]

well, I just moved and had to have my son's 89 D-150 transported up, I just put a new crate 318 in it, has 700 miles. transporter could not get to where we live, so, wife and daughter went to meet him, on the way home, lower radiator hose blew.. daughter did not know the temp gauge on dash cluster did not work, and never saw the after market gauge!.. she stopped when she smelled and saw smoke... I got to her 20 mins later.. temp gauge was PEGGED at 300 + degrees ! towed it home, drained oil next day, no metal in oil, filled radiator added fresh oil and filter .. no oil in water, or water in oil, still has good oil pres.. but top end sounds like a coffee can full on nuts in a paint mixer !
how bad do you think it is cooked ?? am i looking at another motor ??

 

[Don selleck]

my vote is at least heads if not worse, i would pull it and disassemble and look at everything.

 

[wyrmrider]

most likely toasted the rockers and guides
ring tension has gone away
you might get by with new guides and valve gear and new rings
the oil most likely did not get that hot so crank and rods should be ok
just double check everything
surprised that heads are not cracked
magnums would be cracked
check the deck, maybe a pressure check before taking it apart
run a compression check b4 taking it apart just for giggles

 

[Curiousyellow71]

318 you have at least a chance of it living again. I watched a demo derby one time.. a 4dr satellite with a 318 got the radiator damaged early and it started smoking from the leak....10 min later it stopped smoking cause there was no more coolant to leak...it went another 45 minutes...still running. Then, the gal driving it killed it. Thought no way its done.....she fired it right back up. Everyone cheered. May have gained a few mopar believers that day. Close to a hr without water...only a 318 would still run like that. Too top it off...after she won she left it there idling.

 

[jprather]

i am soooo thankful its a 318 not a 360

 

[Curiousyellow71]

I would be worried if it has pressed in valve seats. Getting that hot...the head expands and a valve seat can fall out ending up on top of a piston... Not good when that happens. If the seat stays intact it can just make a knock...if breaks up...very bad.

 

[Cranky]

Several things could have happened for it to be rattling. 300 gauge reading might mean more for the valve springs. Pull the covers off and take a look and might even press down on a couple to see if any of them will compress by hand. Teens usually don't have much spring pressure anyways. Make sure the pushrods are all good. Lifters could have been affected too. If it wasn't smoking at start up after getting that hot, the rings may be ok. How thin was the oil when you drained it? What weight did you put back in? Might try a bottle of STP and see if it makes any difference in sound. Sounds like maybe your thermostat stuck causing the lower hose to blow off?

 

[FJ6AAR]

Just drive to it quiets! You will be surprised how long it will run!

 

[BSB67]

well, I just moved and had to have my son's 89 D-150 transported up, I just put a new crate 318 in it, has 700 miles. transporter could not get to where we live, so, wife and daughter went to meet him, on the way home, lower radiator hose blew.. daughter did not know the temp gauge on dash cluster did not work, and never saw the after market gauge!.. she stopped when she smelled and saw smoke... I got to her 20 mins later.. temp gauge was PEGGED at 300 + degrees ! towed it home, drained oil next day, no metal in oil, filled radiator added fresh oil and filter .. no oil in water, or water in oil, still has good oil pres.. but top end sounds like a coffee can full on nuts in a paint mixer !
how bad do you think it is cooked ?? am i looking at another motor ??

How long did you run it afterwards.

 

[jprather]

How long did you run it afterwards.

Havent ran more than 3 or 4 mins at a time.. still starts and runs

Does not really smoke

 

[dadsbee]

Wow and when I intentionally tried to blow up the 318 in our '69 Fury II so that I had an excuse to put a Hemi in it, in 1978, I first took the coolant out and put a brick on the pedal for over an hour. Next up was draining the oil out and putting a brick on the pedal for a long time. It stopped, but would soon start again and run... finally my Father came around the corner, chewed me out good and said "FOR GOD SAKES.. Just DO IT Already ! "

 

[PRHeads]

Fresh rebuild + 300*?

I wouldn’t be surprised to see some stuck valves.

Pull the valve covers, bump it over, watch each valve to make sure it looks like it’s going thru the full lift cycle.
When each valve is closed, check for clearance between the rocker and valve.
There shouldn’t be any.

If that all looks good, then it’s compression test time.

 

[wyrmrider]

not just 318
slant 6 would run forever
documented trip from LA to San Diego with no oil
Had STP

 

[Cranky]

Wow and when I intentionally tried to blow up the 318 in our '69 Fury II so that I had an excuse to put a Hemi in it, in 1978, I first took the coolant out and put a brick on the pedal for over an hour. Next up was draining the oil out and putting a brick on the pedal for a long time. It stopped, but would soon start again and run... finally my Father came around the corner, chewed me out good and said "FOR GOD SAKES.. Just DO IT Already ! "

That's so freakin funny!! I did something similar to a poly teen in my first car when I was about to swap a 383 into it and tried to blow the old tired teen before removing it lol

 

[jprather]

I dont believe it ! Idled truck for about 15 mins, changed oil again.. sounds like new ! quiet, no smoke !!

 

[BSB67]

I'm not really surprised. That's why I asked how long you ran it after. Usually if your just driving along, it'll start locking-up as the piston get tight before damage is done.

 

[Don Frelier]

One of my good friends in high school/college had a 74 Dodge Monaco with a 360 he got from his grandmother with just over 100K.
She had overheated it massively at least 3 times.
The intake heat riser cover underneath was completely plugged with carbon.
The top of the heads weren't much better.
Cleaned it all out, new valve seals, plugs, wires tune up.
It ran like a top had a ton of power in 2nd gear on the highway.
The LA series is one of the most durable engines, not far behind the slant 6.