Oil pump kaput!

[2SSCAMARO]

I believe if all the facts were known, modded vehicles are more than likely experiencing failure rates at a much higher level than stock vehicles, that's why the dealers see less failures than the forums see. Also there are practices that could contribute to the seized relief valves such as: Deciding to use 10W40, 20W50 oils, aftermarket oil filters that either increase or reduce the system oil pressure vs the PF48. Driving habits such as a lot of short runs that do not allow the oil temp to get up to and maintain 225* long enough to cook off and remove contaminates from the oil. The frequency of oil changes. Incorrectly altering and effectively reducing the PVC system's ability to remove contaminates from the oil. Jacked tunes that are excessively rich and improper fan settings. Not allowing for proper warm up of oil temp before doing spirited driving. I'm fairly confident that if GM's warranty history revealed a unacceptable monetary loss on the oil pumps, they could have melling spec pumps built for less than melling but even if there were an additional small cost, at GM's scale, it would be a rounding error in the cost of a Camaro.

[litle88]

Just because you have a cam doesn't mean you have to go thru this or you don't have to use 20/50 or 10/40. The fact is the pumps are junk and are cost effective even to the bean counters at GM. They have been failing since 1997 and have not changed much except on the Ls7's (dry sump) this is my first L99 failure that I have seen and coincides with what the melling engineer said were the factory weaknesses. Melling 10296 pump is reengineered with different materials and are already blueprinted and will last you 200k miles plus according to the engineer.

[LeanPocket]

Am I just lucky that my l99 pump still functions correctly?

[2SSCAMARO]

I would say forum sponsors like BeckyD at Rodgers Chevrolet who should have access to failure stats (at minimum from her dealership) could shed some light as to whether or not you are lucky. Also there are several top shops that are forum sponsors who could share their "first hand" experience of stock pump failures. They could state their opinions on whether or not the pump failures were solely because of, as little88 claims are "junk" or whether there were extenuating circumstances such as improper reinstallation, inadequate preventative maintenance, abuse etc. I, for one, would be interested in seeing a few posts from the above mentioned members regarding their opinions. It is only fair to disclose my 2010 L99, built in July of 2009, is heavily modded, blown, cammed, and LS3 converted. It still uses the original L99 oil pump. PSI at startup is 65, fully warmed up at cruise is 45, idle @650-700 never less than 30, WOT 65. Therefore at this point, I am not convinced the pumps are junk.

[POWERFREAK]

Originally Posted by LeanPocket

Am I just lucky that my l99 pump still functions correctly?

No, don't worry about it.

[CFD]

Originally Posted by LeanPocket

I guess for comparison purposes, what weight and brand oil were you using?

Originally Posted by 2SSCAMARO

I believe if all the facts were known, modded vehicles are more than likely experiencing failure rates at a much higher level than stock vehicles, that's why the dealers see less failures than the forums see. Also there are practices that could contribute to the seized relief valves such as: Deciding to use 10W40, 20W50 oils, aftermarket oil filters that either increase or reduce the system oil pressure vs the PF48. Driving habits such as a lot of short runs that do not allow the oil temp to get up to and maintain 225* long enough to cook off and remove contaminates from the oil. The frequency of oil changes. Incorrectly altering and effectively reducing the PVC system's ability to remove contaminates from the oil. Jacked tunes that are excessively rich and improper fan settings. Not allowing for proper warm up of oil temp before doing spirited driving. I'm fairly confident that if GM's warranty history revealed a unacceptable monetary loss on the oil pumps, they could have melling spec pumps built for less than melling but even if there were an additional small cost, at GM's scale, it would be a rounding error in the cost of a Camaro.

It seems that almost all the failures reported are for the LS3 not the L99 but the two pumps don't really seem that much different if at all, if so, it may just be different preasures or bleed off pressure.

I think the reason why some dealers don't see a lot of failures is because a good many people modify or tune their cars and don't waste their time even taking them to the dealer.

In my case the failure was due to the relief valve as with the LS3's that have been reported. I use Mobil 1, and an AC oil filter so that variable can be eliminated. The pump has never been removed, loosened or messed with in any way. I change my oil and filter regularily and well before the DIC indicates it is necessary. I always warm up my car but do drive quite agressively at times both city and highway driving so most of the reasons for it to fail are not because of poor maintenance or improper useage. Nothing has ever failed such as timing chain/tensioner, trunions or anything else that would cause debris other than normal wear to cause it.



NOW FOR THE UPDATE!!

Got it back together today, started up and the top end quited down fairly quickly WITH THE EXCEPTION OF ONE LIFTER. I tried a few start/stop cycles but it did not free up. I pulled the valve cover and rocker and can see no obvious damage, tomorrow I am going to use a camera to see if the lifter looks in tact, if so I will let it run a bit and see if I get lucky but at this point It looks like the top is coming off.

[2SSCAMARO]

Originally Posted by CFD

It seems that almost all the failures reported are for the LS3 not the L99 but the two pumps don't really seem that much different if at all, if so, it may just be different preasures or bleed off pressure.

I think the reason why some dealers don't see a lot of failures is because a good many people modify or tune their cars and don't waste their time even taking them to the dealer.

In my case the failure was due to the relief valve as with the LS3's that have been reported. I use Mobil 1, and an AC oil filter so that variable can be eliminated. The pump has never been removed, loosened or messed with in any way. I change my oil and filter regularily and well before the DIC indicates it is necessary. I always warm up my car but do drive quite agressively at times both city and highway driving so most of the reasons for it to fail are not because of poor maintenance or improper useage. Nothing has ever failed such as timing chain/tensioner, trunions or anything else that would cause debris other than normal wear to cause it.



NOW FOR THE UPDATE!!

Got it back together today, started up and the top end quited down fairly quickly WITH THE EXCEPTION OF ONE LIFTER. I tried a few start/stop cycles but it did not free up. I pulled the valve cover and rocker and can see no obvious damage, tomorrow I am going to use a camera to see if the lifter looks in tact, if so I will let it run a bit and see if I get lucky but at this point It looks like the top is coming off.

It certainly does not sound like your driving habits or preventative maintenance practices have contributed anything towards the pump failure. Did you happen to gage the failed pump for centering before you removed it? Because if you found that it was not centered correctly and you did not remove it and replace it previously when you did the cam, it would be an indication that it was not installed properly at the engine assembly plant.

[CFD]

Originally Posted by 2SSCAMARO

It certainly does not sound like your driving habits or preventative maintenance practices have contributed anything towards the pump failure. Did you happen to gage the failed pump for centering before you removed it? Because if you found that it was not centered correctly and you did not remove it and replace it previously when you did the cam, it would be an indication that it was not installed properly at the engine assembly plant.

I did not check to see if it was properly centered were as the failure was not directly related to the gears but to the relief valve. I do not think there was an issue with the installation as if it was not properly centered I believe it would be evident by scuffing on one side of the housing, the sides of the housing seem to be in pretty good shape.

[2SSCAMARO]

One other possibility is very small foreign matter getting into the system upstream from the filter during cam and heads work. With the very tight clearances in the relief valve cylinder, very small particles that would lead to galling and scuffing could cause damage to the valve and walls as they pass through the valve clearances during cycling. Once the valve and walls have been scuffed, continuing deterioration could occur merely from the cycling of the valve without contamination until the point seizing occurs.

[CFD]

Originally Posted by 2SSCAMARO

One other possibility is very small foreign matter getting into the system upstream from the filter during cam and heads work. With the very tight clearances in the relief valve cylinder, very small particles that would lead to galling and scuffing could cause damage to the valve and walls as they pass through the valve clearances during cycling. Once the valve and walls have been scuffed, continuing deterioration could occur merely from the cycling of the valve without contamination until the point seizing occurs.

In theory, it is possible but as mentioned the cam change was done 40,000 miles ago, since that time there have been many oil/filter changes. There have been many failures reported on stock motors where this would not hold true. It almost appears that you are looking for an excuse as to why the pump failed but it is apparent that there is a problem with either the pumps design or, as I believe, the problem may be due to the steel on aluminum parts. There is a lot of scuffing on the housing and gears most likely caused by some sort of debris but I believe the debris is not foreign to the motor but a result of the wear charecteristics of steel on aluminum.

[POS Dakota]

Originally Posted by 2SSCAMARO

One other possibility is very small foreign matter getting into the system upstream from the filter during cam and heads work. With the very tight clearances in the relief valve cylinder, very small particles that would lead to galling and scuffing could cause damage to the valve and walls as they pass through the valve clearances during cycling. Once the valve and walls have been scuffed, continuing deterioration could occur merely from the cycling of the valve without contamination until the point seizing occurs.

It's not a possibility. It's a fact!
But it will happen to an engine that's never been opened if you drive around with black oil in it all the time.

The filter only filters for so long....then it stops.

[CFD]

Originally Posted by POS Dakota

It's not a possibility. It's a fact!
But it will happen to an engine that's never been opened if you drive around with black oil in it all the time.

The filter only filters for so long....then it stops.

Oil does get contaminated due to normal wear but there have been many failures on vehicles that are maticulously maintained and on vehicles with minimal mileage in comparison to mine. All the above mentioned senarios are possible but where as there are so many failures, as well as a tsb on them and the fact that Melling has also identified a problem and has taken steps via different materials, hardcoating etc. to prevent it, many of the problems, perhaps not all, cannot be prevented by normal maintenance. Another interesting fact is that many change the oem pump when doing cam changes, timing chain/tensioner changes. These motors are subject to the same possibilities of poor maintenance,contamination etc. yet we haven't seen any Melling failures that I'm aware of.

[2SSCAMARO]

Originally Posted by CFD

In theory, it is possible but as mentioned the cam change was done 40,000 miles ago, since that time there have been many oil/filter changes. There have been many failures reported on stock motors where this would not hold true. It almost appears that you are looking for an excuse as to why the pump failed but it is apparent that there is a problem with either the pumps design or, as I believe, the problem may be due to the steel on aluminum parts. There is a lot of scuffing on the housing and gears most likely caused by some sort of debris but I believe the debris is not foreign to the motor but a result of the wear charecteristics of steel on aluminum.

I am not looking for an excuse. I am looking for rational. When one of the above posters has a pump that has already done 120,000 + miles, the intrinsic design flaw theory looses some credibility.

[CFD]

Originally Posted by 2SSCAMARO

I am not looking for an excuse. I am looking for rational. When one of the above posters has a pump that has already done 120,000 + miles, the intrinsic design flaw theory looses some credibility.

I, untill a couple of days ago, used to say that I have almost 70,000 miles with no problems and then mine went. There are many tsb's and recalls on vehicles, it doesn't mean everyone of them will fail, it means there is a potential problem and I believe it is true with the oil pumps on these motors. It may be the pump's design, it may be the materials or it may be a combination of both but there are too many failures to overlook.