Engine Leak????

[Big T]

I have/had a couple leaks on my '99. One apparently was on the rear most fitting of the stainless oil cooler lines. Basically the fitting had worked loose a bit and I was able to grab and tighten it without remove the 4wd oil filter adaptor. Subsequent run test revealed that leak to be solved.

The second leak is a bit of a mystery as to what it is, but not where it is. The leak is on one of the two lines from the transmission to the transmission cooler right at the brackets below the point where the turbo oil return line enters the block. You can see the drip on the forward (bottom) of the two brackets in this photo:

The fluid is clear and somewhat oily like diesel fuel. It hits the driveway and leaves a spot, but it eventually evaporates. You can see that it leaves a lot of the stuff wet such as the front differential mount in foreground of the picture. It's clearly coming from those two lines at the bracket as I wiped everything dry in that area then observed the leak with the engine running. I checked the transmission dipstick and it's at the full line. Any ideas?

 

[bison]

Could be coolant leaking on the lines trough a hole in a frostplug behind the motormount,..
Should be able to smell it,..diesel or coolant.
Trannyfluid is red(supposed to anyway)

 

[Big T]

I'm thinking you've nailed it on the coolant. While at the supermarket, it puddled up on freshly sealed asphalt. It looked greenish and more like water.

So if it is the frostplug behind the motor mount, how do I address it?

 

[Big T]

So where is this frost plug? Can I get a clear visual on it to confirm a leak? How hard is it to R&R?

 

[bison]

That frost plug is smack center hidden underneath the engine bracket.

I would use a pressure tester and pressure up the coolant system to find out where the leak actually originates,i mentioned frostplug but it could be higher up:ie headgasket,quikconnect..etc.

If it happens to be the frostplug then you have to remove the motormount and the engine bracket. I can't say you can access the frostplug that way cause i never had to but one can try trough the wheelwell, maybe pull the mount trough bolt on the other side and jack the front of the engine up as high as possible.

On the other hand when one is bad than the other ones can't be trusted either.....

Have fun.

 

[Big T]

Is that frost plug behind those two lines? I did not see the fluid in question on the block, only on the lines. With the engine on, the drip blows back and lands on the mount in the foreground. I would need to see a pic of a block outside the truck to see where the frost plugs are located.

 

[Big T]

I'm inexperienced on this. Not familiar with a pressure tester for the coolant system. Where do I get one and How do I use it?

 

[bison]

It's the best pic i have.
The furtest of the 3 plugs is the one.(round bosses in a row on the side in view)
The mount bracket bolts right over top of that plug.
Hope it helps.

Any autosupply store should have these coolant testers. 'Stant' is a common brand
A handpump with gauge and a hose with rad cap that will fit the recovery tank filler neck.,,, about $40- 45 me thinks

 

[Big T]

That pic helps. Now I know what to look for. I'll pick up a pressure tester and have at it. I also have a similar leak issue on a Volvo marine diesel and have not been able to confirm the source. So the pressure tester will have two immediate uses

 

[Big T]

It's the best pic i have.
The furtest of the 3 plugs is the one.(round bosses in a row on the side in view)
The mount bracket bolts right over top of that plug.
Hope it helps.

Any autosupply store should have these coolant testers. 'Stant' is a common brand
A handpump with gauge and a hose with rad cap that will fit the recovery tank filler neck.,,, about $40- 45 me thinks

Looks like 3 freeze plugs on each side and one on the rear. So if it is indeed a leaking freeze plug and I need to replace all of them, then it's looking like I need to pull the engine. So......how hard is it to pull the engine? How long will that take?

 

[Big T]

Well lucky me. I did another inspection with the benefit of mid-day sunlight. Wiped everything clean and dry and traced down the leak. You'll never guess.
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There was a rubber hose that was intersecting one of the transmission lines at a right angle. It was as if it connected there. I reached up to see if it moved and it did. It had a slow drip coming from it and............................................................................it was diesel. So I go up top to trace it and it goes right to the bleeder valve you would open to see if you've got pressure from the lift pump. I note that the T handle is slightly askew and I twisted it to fully close it. No more leak and damn feeling relieved that I don't need to pull the engine. The other oil is also now resolved based on no drips after several test drives.:hurray::driving::nanawrench:

 

[JMJNet]

Glad you found it.

In a Suburban, for coolant leak, I will check the lines that split the front and rear coolant heater/coolant lines.
That tee is plastic and overtime, it will crumpled.
The truck does not have it.

 

[bison]

Proper diagnosis is everything,glad you found it....you may want to smell the drippings next time

BTW, the "frostplug" on the rear of the block pic altough it looks similar to one is not a frostplug but a cap to plug the camshaft bore.

 

[Big T]

Proper diagnosis is everything,glad you found it....you may want to smell the drippings next time

BTW, the "frostplug" on the rear of the block pic altough it looks similar to one is not a frostplug but a cap to plug the camshaft bore.

I thought it smelled and felt like diesel, but my sense of smell is not that great.

It would appear by the lack of drips that I've solved all the leaks, except that my coolant reservoir was low. However, it's been like 15K miles since I've worked on anything with the cooling system. No coolant in the oil or vice versa. So I topped it off.