Coolant leak from where ?????

ban_dit68 · #1 (**permalink**) 02-14-2004, 07:51 PM

Hey guys, Ive got a little problem. At least I hope its little. My 1984 F350 420 diesel has an anifreeze leak. It leaks in the area of where the block heater is. I replaced the block heater and the leak is still there. What else could be making the coolant leak in this area? I dont see any hoses in the area that could leak and with the rubber thing covering the lower block its hard to pin point where its coming from. Any thought would be appreciated.

Thanks,
Rob

My first Diesel so please be patient with me......

horton-racing · #2 (**permalink**) 02-14-2004, 08:09 PM

Did you clean the hole up with some emery cloth before you installed the new block heater? Could also be a cracked block or bad head gasket. Your upper heater hose could also have a leak that may be running down the block, doubtful though. What rubber thing are you talking about? Does it leak all of the time or only when hot? You may have to remove the rubber thing (whatever it is) and maybe the starter to get a good look up the side of the block. Good luck and keep us posted.

ban_dit68 · #3 (**permalink**) 02-14-2004, 10:27 PM

I guess I'll have to get down and dirty when it warms up and check it more closely. It's possible I rushed in the block heater too fast and didn't clean it well enough. We do still have some snow on the ground and I was in a hurry cause I was chilly. The rubber thing i was referring to I think is a sound deadener that covers the block. I guess it's not really rubber since I can rip off pieces of it...

Rob

Dave Sponaugle · #4 (**permalink**) 02-14-2004, 10:56 PM

There is no rubberlike coating on the block.
Have you had this truck long?
Sounds like someone put undercoating or something similar on the block.
Hope it was not to hide the leak till you bought the truck.
You have several soft plugs on the side of the motor that could be leaking. (Same height on the side of the motor as the block heater)
Next higher than that is the head gasket.
You also have a heater hose connection in the middle of the head that could have a bad hose clamp in it or cracking hose where it is not easy to see.
Check the water pump weep hole, if someone sprayed something on the motor the antifreeze could be getting behind it and running around the motor till it got to that area where it sounds like you have pulled some of it off.

What ever is on it, it is not supposed to be there unless it is paint, and that is not rubber looking. I would scrap it all off and see what someone is hiding under it.

RWDCelicadude · #5 (**permalink**) 02-15-2004, 09:10 PM

I had similar problem and today I found the solution. The coolant had been leaking down on top of the starter and dripping onto the exhaust so I thought it was coming from the block heater, but no. After getting a radiator pressure tester and removing the starter for better viewing it was found that the thermostat housing was leaking. Coolant was running down the side of the block and catching on the top edge of the oil pan where it would run back until it got to just above the starter, then it would drip off. If you lie down underneath the radiator with a flashlight and look up towards the top edge of the fuel pump you can see the coolant running down the side of the block. That's the only place I could see it even after I knew exactly where it was coming from. It looks like a pain in the ass to change the thermostat and housing gasket but I'd be willing to bet it'll fix the leak.
It sounds like this may be the same problem you're having and it's easy to check once you know where/how to look for it. I'll probably be doing this tomorrow and will let everyone know how it turns out.

ban_dit68 · #6 (**permalink**) 02-18-2004, 07:14 PM

Ummm I finally got under the truck today to get a better look. As it figures it looks like I have a small crack in the block just to the left of the block heater. I removed the covering and discovered it. I have only had the truck a few weeks and bought it as is. Now my question is..... What can I do to fix the problem? It is a small crack and only leaks when it is running. It is also in an area that is easy to get to. Any Ideas?

Rob

75diesel · #7 (**permalink**) 02-18-2004, 08:11 PM

IF YOU CAN, DRILL THE ENDS OF THE CRACK AND BRAZE THE CRACK IF YOU KNOW HOW

pnose · #8 (**permalink**) 02-18-2004, 08:27 PM

How long is the crack? It may be possible to cast weld it.As stated above drill a hole on each end of the crack and every 1/4 inch between them.Best results will be obtained if screws are screwed into the holes you drilled before welding.You should probably talk to a reputable welding shop as this is not a repair for the novice mech or welder for that matter.In the mean time if it was me i would deffinatly go back to the person that i bought it from to see if they are willing to do something for you.