Hello,

I have a hidden coolant leak in a 99 Ram van 1500 5.2L.

It only leaks after it has been shut off and cooled down . Doesn't leak at all while running. Never overheats and runs just fine.

I can't see where the leak is coming from while underneath the van or with the doghouse off looking from rear to front of the engine.

It drips just behind the oil pan. Maybe 1/2 a cup to 1 cup until it finally stops.

Anyone else experience this?
any ideas?

 

On the back of the engine are two freeze plugs. When either of these start to leak the antifreeze will run down the back of the engine and drip out the bottom just where you're seeing it. In order to access these two freeze plugs, the tranny has to come out. You MIGHT be able to confirm this and see the leak if you remove the crank sensor and shine a bright light into the crank sensor opening. The crank sensor is the one on the top of the passenger side of the tranny held down by two bolts and has a 3-wire connector, right where the engine and tranny mate.

 

Hi Alloro. Thanks for the reply.

(1) would a can of stop-leak seal the freeze plugs?

(2) is it likely that the freeze plugs will blow out if the van is driven?

--oddly enough, some days it will leak just a little, some days as mentioned above, a once in a while it won't leak at all.

 

dont use stop leak that causes more probs down the road. before condeming anything get a trace dye at any autoparts store and a black light this will make pinpointing ezer. get a cooling system pressure tester i think you can rent one from autozone for free. freeze plugs rarely blow out but they do rust and develop pin holes to eventual complete failure but its not like blowing out just progressively more leaking.

 

Hi shelbydaytona,
Thanks for your input. I'm going to start with Alloro's suggestion with crank sensor and if I can't spot it there, using dye and pressure test as you suggest.

PIA that manufacturer would hide these at tranny/engine juncture.

Thanks again for suggestions.

 

True but we can at least count our blessing that the tranny comes out of these vans very easily.

If you're in a pinch, slowly pour in a 1/4-1/2 of a tube of the aluminum power sealer. I've found that using this little amount won't cause any clogs or other problems, unless there is a problem ready to happen anyway.

 

i'm sure everyone will disagree with me, but with the freeze plug leaking on the back of the engine and having to remove the transmission to fix it ---- i'd try some stop leak.

 

Hi Alloro & dhvaughan,
Thanks for both inputs.

Alloro - is aluminum power ( powder?) sealer also a stop leak of some sorts?

Does any parts place carry this?

 

Yes, the aluminum powder is a leak sealer, you will find it in most all auto part stores and it is about 3 inch high tube in a cardboard package. The same company also makes a copper powder as well, and they are usually side by side on the shelf with other leak sealers.

I do not remember what the brand name is of the product.

 

Yes I meant to write powder and not power. Sheesh, one little mistake and everyone rides my butt.

The product is called AlumAseal.
http://www.goldeagle.com/brands/alumaseal/faq.aspx