Need some opinions about a jeep engine failure
 

Good friend of mine (he's like a second father to me) took his Jeep to the local quick service for an oil change as he normally does every 3K miles. He noticed the oil change was taking longer than usual when the manager approached him and asked him to step into the garage. When they went out into the garage the manager started the jeep and and it made a loud knocking/slapping noise and the engine was shaking violently. At this point they were unsure what it was and offered to look further into it and offered him a ride home, which he accepted.

Hour or two later they call and say the oil was milky (provided a sample in a jar) and thought it must have a blown head gasket. He called AAA and had it towed to his local mechanic that has done some work on this jeep in the past. The results just came in, he has zero compression on cylinder 2 and another cylinder is really low. The mechanic noted that there is no sign of "milky" oil and he believes the #2 piston has a hole or the rings are completed gone.

It has the 4.7L V8, 220K miles on it. Normally I wouldn't think much of this but I feel as if the engine letting go at a shop during an oil change is an odd coincidence. Was the engine fired dry and are they trying to cover it up?

He is very meticulous, his last jeep went 360K miles on the stock engine and auto transmission, still drove fine when he donated it.

I take it that the place was not the type that you drive-through and stay in the vehicle?

Proving that the damage occurred at the oil change place may be difficult without evidence of some sort that all was well when he drove in.

Good luck to your friend and please let us know how it turns out.

No it's not one of those places.

Logic would dictate that if indeed it's a holed piston and destroyed rings, that damage would take at minimum many minutes of driving. Not likely anything an oil change place could have done to inflict that (if the diagnosis is correct).

couple questions......

1....did they change the oil and filter?
2......did they charge him and give him a receipt?

if the oil was milky it would've revealed itself when they drained it....did they tell him before completing the oil change?...however if it was not and they started the truck with no oil then there is a chance that they contributed to the damage, if he has a receipt that will be his only recourse to have them pay for it.....
with a claim like that he'll deal with their insurance company so need some sort of proof....

There are a couple of things to have looked at here and none of them are good. Dropped valve seats, cracked heads, and even failures between cylinders occur on the 4.7 engines.

Another possibility is that it jumped mechanical timing and bent some valves on one side (that of course would not explain the milky oil).

angela

I had a car on the lift once doing a clutch. I let it down went to test drive it and the water pump failed.

The customer was angry but I would not replace it for free. Mechanical things fail. In this case I have trouble seeing how they could have caused this to happen.

That is odd. I've had a 4.7 jeep and I don't know if I would believe it would suddenly let go like that. Then again if its milky it probably wasn't due to being run without oil and its due to be overheated. It does have some miles on it but nothing crazy.

I think he drove it in that way whether he knew it or not.

220k on a 4.7? Call it done, he got his money out of that car. A lot of those 4.7's never it make it that far as noted above.

I expect it,s a coincidence.

How would a holed piston give you emulsified oil? I think you would see some evidence of this when you tore it down to look it over.

Why would they tell that tale at all? Did he pay for an oil change, did they show him the ostensibly "milky" oil? I don't question that the motor could give out, but if he drove in running on 7 you would think he would notice it.

Here is what happens on the 4.7:

http://forums.pelicanparts.com/uploa...1337656077.jpg

The seat drops and destroys the piston and the lining, coolant from the now cracked lining goes into the pan, tons of fun.

Yes, they are covering it up, if there isn't any coolant in the oil. I believe they ran it dry and it let go. I would file a claim if I were your friend and see where it goes. Small claims court if the lube place doesn't budge. Not sure what's required for documentation, but I'd take pictures of the oiled surfaces at tear down, bearings. Also pictures of the oil pan / oil to show that there is no coolant. I would also keep a sample of the oil and send it in for analysis (no coolant, high levels of metals).

This is why I change my own oil. At least I know what I did wrong when I run it dry. ;)

G

I see the problem... that there is a Chrysler product. ;)

A good technician can tell what happened within minutes of having the motor apart.


Starvation will present itself much differently than a dropped valve seat, broken ring, or blown head gasket. If they fired it up with no oil, it will be visible.

While it's still in the truck, do both a compression test and a leak down test. It's pretty easy on a 4.7L V8. Then, pull the head on the bank where that cylinder has no compression. Then drop the pan.

If they forgot to fill it and ran it for a minute, that damage would be clearly evident. If it had any other type of damage, it happened over a period of time and would also be clearly evident.

I'm in the business and would agree. The 4.7 is (MO) a very good engine overall but @220K - call it a day. If he REALLY likes the vehicle, buy another like model with low mileage and history. As for the oil change shop................most likely they bear no fault.

bad service
 

That is why I change the oil in all our vehicles. Don't like to but I there's no question it's done right. I can choose what oil, what filter and grease all the zerk fittings. No yo yo's anymore

Keep in mind they took over an hour, he said the jeep was in the stall for well over 45 minutes.

Yes they changed the oil and filter, he has a receipt from them. There was no mention of the oil being milky when the car started making the noise. After they brought him home they allegedly changed the oil again and found the new oil was milky. Therefore the old oil was not milky, the oil that was in the engine when he showed up for the oil change.

Hard to believe that is possible. This isn't a little knock or tap, two cylinders are gone. The tech that drove the car into the garage even said it "drove in fine"

This is what the mechanic said as well. Plugs came out clean so this has not been confirmed yet.

Compression and leak down were done, hence the reason why we know it had zero on one cylinder and next to nothing on another.

The tear down is in process but it's a few hours of work. The engine bay is cramped to say the least and pulling the pan takes a couple hours from what I have been told.

His jeep is in pretty good shape, you would never guess it has the miles on it that it does so he willl likely replace the engine.


Thanks for the feedback.