Odd coolant leak

rhkcommander

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Came out to check on my truck and work on it, its been sitting for a week or two while I chase fuel leaks n all... No more diesel fuel drop trails LOL. Still maybe some air leakage but she starts :dunno Work-in-progress

I saw a drip falling every couple seconds, coolant. I'm trying to find where its coming from but the drip is falling from the positive starter power cable...

I'm thinking its running from either the lower rad hose or oil cooler maybe? Water pump? I will wrap the lower hose with a towel tomorrow to see if it gets soaked. I know when I added the lower hose heater that the hose was most likely overdue... I've only gone maybe 100 miles and installed it in late fall but the problem has just developed while its been sitting

Not a head gasket unless the coolant passage gave out somehow :dunno. No smoke out the exhaust, no bubbles in radiator, no watery film in oil as far as I can tell. Heads/exhaust looked mostly dry, i didn't see any stream that indicates a leak there...

Thanks for any tips and have a good weekend OB ;Sweet
 

OLDBULL8

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Positive starter cable is on the right.
Oil cooler is on the left.
Lower rad hose is on the left.
Water pump is in the center.
Block heater? Could be there.
 

Silver Burner

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Probably block heater. I have the same problem, except now on cold mornings I have a small pool of coolant under the truck. Soon as you start it and warm it up, no leak at all until it cools off to close to freezing. But there is a lower radiator hose on the right for the heater not far from the block heater insert, so it could be there.
 

Dieselcrawler

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could be rear head gasket on pass side. mine leaks when put a heavy load to her and drips onto the starter.
 

rhkcommander

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I hopped under and took a look... Still dripping, I think I found the problem but the prior owner rigged something to hide the leak IMO.

Looks like he covered it in some wax crap or something similar, not normal bees wax since that'd melt on first warmup but I don't know :dunno take a look. Maybe its a glue :dunno You can see drips of my red coolant on the oil pan and starter

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I think the motor is an early year, I know the block heater is known to leak and all and the block is cast weakly in early years, so should I use a freeze plug or new heater or what :dunno
 

itsacrazyasian

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looks like permatex spray and seal.

only thing up there is the block heater

my 6.9 had a crack in the block there. i sealed the block heater and the crack with some jb weld (not quick) the regular jb is much stronger.
 

G. Mann

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I'll take bets it's the heater core just inside the firewall. I had the same problem on my 85. It drove me nuts trying to locate it until it finally puked completely and flooded the passenger floorboard. The crack was following the heater line back out to the engine compartment and I couldn't see the drip from bottom of the hose.

Have a look there first with your fingers. Good luck.
 

G. Mann

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I'll take bets it's the heater core just inside the firewall. I had the same problem on my 85. It drove me nuts trying to locate it until it finally puked completely and flooded the passenger floorboard. The crack was following the heater line back out to the engine compartment and I couldn't see the drip from bottom of the hose.

Have a look there first with your fingers. Good luck.
 

icanfixall

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Early block... Crap smeared on like that... My guess is a cracked block... Sorry for the bad thoughts but that my SWAG.....:(
 

rhkcommander

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If its cracked would welding/brazing/ETC with good prep or that jb weld do any good? I figure its not under too much pressure - just the cooling system :dunno

I know i could use some higher temp lead-free solders and either solder or braze it, them suckers wouldn't melt even when its fully warmed up since they dont liquidate till around 480°F or so and the coolant shouldn't ever get near
Heres hoping its not too bad, I've been F---ED over enough with this truck and I can't afford a new block for a while. It'll be a nice truck once I finish cleaning up all the idiotic messes =)
 
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rhkcommander

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Took her for 240 mile drive, checked ocassionally and coolant stayed above the cores.

Also got ~ 16.87 mpg if my trip meter works accurately, I know its within +/-5miles though using google maps. On oregon coast with some wind resistance and needing alignment, alignment and new pump might up it a lil more eh?
 

icanfixall

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All you can find for any 6.9 or 7.3 blocks are a replacement block... nobody makes any new blocks... Yet... There is new cylinder heads available for the 7.3 engines.....:thumbsup: None for the 6.9....:cry:
 

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