Esso XD-3 0w30, 10000KM, '99 Grand Caravan 3.8, coolant leak..

[rcy]

The oil is Esso XD-3 0w30 that's been in the van for 10000KM. I was losing coolant from the overflow bottle, but couldn't see any external leaks, hence I had the UOA done.

FYI, the numbers in the second column are from German Castrol in use for 2259KM, 3.8 V6 from the same Grand Caravan, but not the same motor. It was the original v6 in the van that had a leaking intake gasket and a UOA confirmed glycol in the oil. Shortly after having it fixed, the motor spun a bearing. I put a used motor in, and now have the same problem with disappearing coolant in the new used motor...obviously I've offended the engine gods somehow...
________________________________
CONTAMINATION XD-3 GC
Silicon 13 7.1
Potassium 432 187
Sodium 236 295
Fuel % Glycol P os P os
Water Soot --- ---
Sulfation 67 36
Nitration 55 34
___________________
WEAR XD-3 GC
Iron 21 5.0
Nickel 0.0 0.0
Chromium 0.9 0.2
Titanium 0.1 0.1
Copper 1.8 0.9
Aluminum 7.1 1.4
Tin 0.6 0.0
Lead 4.1 1.8
Silver 0.0 0.3
____________________
OIL CONDITION XD-3 GC
Boron 11 3.4
Barium 0.1 0.1
Calcium 3123 2573
Magnesium 13 109
Molybdenum 7.8 9.0
Sodium 236 295
Phosphorus 1297 763
Sulfur 3714 2480
Zinc 1270 974
Visc @40 --- ---
Visc @100 11.1 11.7
Oxidation 61 50

 

[Jim 5]

Your silicon number is a little high, that could be contributing to the increased iron.

I would have thought there'd be more lead with a coolant leak...due to con-rod bearings.

Your aluminum number is up significantly, and I'm not sure of the architecture of your engine, but often OHC Cam journals are aluminum with no lead bearings surface, and this could indicate cam journal wear.

You might try the GM cooling system tabs since your numbers don't look absolutely terrible for 10k Km's.

My thought is the most alarming number is the aluminum....however like I said, in my amateur opinion the numbers don't indicate an imminent meltdown.

If this were my engine I'd add the GM cooling system tabs, change the oil to a cheap dino (knowing that it might need to be dumped shortly)and resample for glycol in 1000 km's.

The lab I use for UOA's can sample your oil with a paper strip (like litmus) just to test for glycol..it would likely be alot cheaper than a full spectrum uoa.

 

[Al]

"The lab I use for UOA's can sample your oil with a paper strip (like litmus) just to test for glycol..it would likely be alot cheaper than a full spectrum uoa."

Chances are that by the times you find coolant in this manner its out of control. This potassium is at least 20 times what would otherwise indicate a leak..well before a positive test for glycol would catch it. Glycol tests are a joke.

 

[rcy]

These GM cooling system tabs...do I just go to the parts counter and ask for them?

Cheers.

Also, could the high silicon # be from the K&N air filter I'm using? Should I dump it and go back to the OE filter?

I've already replaced the oil with another 4 litres of XD-3, however, if the tabs work I'll know purely by the level of the overflow bottle. In roughly two months, it went from half full to empty.


Thanks.

[ February 08, 2006, 08:34 PM: Message edited by: rcy ]

 

[Jim 5]

Just go to the counter and ask. They'll know what you're talking about. Be sure to really crush them up well before you put them in the radiator. They're only about $5. They'll make your coolant look brown.

The silicon is very likely from the K&N. Some people have shown good UOA's with K&N's but it think it takes careful cleaning and oiling. I'd test this by switching to a premium paper air filter (or an oem) and seeing if the silicon number goes down. My guess is that just doing this will clear the silicon issue. Also, check your intake and airbox plumbing for loose connections, cracks etc. If you see dust/dirt inside (on the engine side of the air filter) then clean all of that up so it doesn't get sucked in.

According to Al, the glycol tests are useless. I'm going to take his word for it because I really don't know much about it. However, my thought is that wear metals will tell the tale. Also, your coolant loss will tell the tale, the question is, how much is leaking to the exterior, and how much to the inside of the engine.

Good luck with that paper filter and cooling system tabs.

It's of benefit to all of us if you report back with your progress (coolant levels and updated UOA's).

Of course, if you want expert advice, Terry Dyson (in the site sponsor section under "Dyson Analysis) is the real thing...and the consensus is that his advice is always worth the money.

He's also a real gentleman, has been kind enough to give me some free advice on a few points, and is an active contributor to this board and everyone's learning curve. I recommend that if you want the advice of an expert and not a novice like me, you send your business his way.