I posted a few weeks ago about a rattling noise I thought was coming from my supercharger. I have a '05 with a stock blower and motor. 18K miles on odo. The noise would go away after the car warmed up. I thought I was on the trail of a failing bearing in the SC.
About the same time, my oil pressure gauge started reading either 25 psi or zero, but the check gauge light rarely came on. Two years ago the pressure sending unit failed and I had it replaced by the GT Guys in Scottsdale on the way to the LV Rally. At that time we also noted a small oil leak out of the oil pump. I had that replaced at the local Ford dealership under warrantee at the end of 2008. More about that later. I thought I had another bad sending unit and ordered another one.
Anyway, about 10 days ago I filled the car up with the usual 93 and drove about 60 miles running errands. I noticed some valve clatter if I accelerated. I thought I had gotten a bad tank of gas. I went to dinner and parked the car for a couple of hrs. That evening on the way home the engine started clattering like a sewing machine. Didn't miss, no smoke, oil pressure still going up and down on the gauge. Car didn't overheat. I limped on home (12 miles) thinking this is the worst gas I have ever put in a car. I drained the tank and purged the fuel pumps at the connector to the fuel rail. The gas did have some water in it, but not horrible. Put new gas in the car and cranked it up....same horrible clatter...sounded like the timing chain was not tensioned.
Further diagnostics ensued...
1. Pulled the plugs...no metal or residue...they looked normal
2. Checked all 8 pistons with bore scope from above....some mild areas of burned off carbon deposits from the bad gas and water. No holes, normal looking hone markings.
3. I pulled the valve covers...no displaced springs or followers. There was oil present on the cams etc. We did however note that some of the hydraulic lifters were not pumped up with oil. Reaching inside the front engine cover, the R side timing chain was also slack. Hmmm.
4. Put the car on a lift and cursory inspection with the pans off showed no signs of an oil leak. I drained out the engine oil and all 9.5 qts were there. The oil was very black. Let it sit overnight and decanted off the top stuff. There was some non-magnetic "sparklies" in the oil...almost microscopic...probably aluminum. ? if from the chain slapping the timing chain cover. The oil filter had no metal chunks in it.
5. At first I thought the oil pump and oil pump belt looked OK. Surprisingly, the belt was slack but on the pulleys and tensioner. ? had the tensioner failed or loosened.
6. I pulled the cover off the oil pump and the pulley on the pump was spinning freely! A bunch of metal dust fell out. Pictures of the intact pump and the pullley off the pump are below. The splines of the sintered pump pulley are totally gone. We pulled the pump apart and the internals look normal...it rotates freely without binding.
At this point I think my oil pump pulley was failing all along....slowly chewing up the splines. When it finally started freewheeling, the oil pressure dropped and this led to valve and chain clatter as the lifters and chain tensioner are hydraulic. We will pull the rod cap and main bearing cap at the farthest point from the oil pump. I have pulled the oil pan....no metal debis... and the cylinder walls look OK from below also. Nothing looks bad visually. Crank looks OK as best as I can tell. If there is no bearing scoring...maybe I dodged a bullet. The oil took all the heat for sure. A testament to synthetic oils.
Several questions/issues arise...
1. How did the pulley fail? The locking nut was on tight. There are no splines whatsoever inside the pulley. The pump is not fozen up itself or the belt most likely would have failed.
2. Maybe the pulley was installed improperly when my pump was replaced under warrantee. Maybe a broken tooth on the splines. The pulley is usually pulled off and placed on the new pump shaft, as best as I can tell.
3. Is there a better aftermarket pulley out there...billet? The sintered metal splines failed completely...powdered, pulverized.
4. Assuming the bottom end of the motor looks OK, once the new pump/pulley is installed...other diagnostics....check compression, leak down?
5. Anyone else seen a oil pump/pulley fail this way?
6. Doubt bad gas had anything to do with this, just coincidental?
Sorry for the long winded story. Thanks to Rich for his time on the phone trying to figure this out.
About the same time, my oil pressure gauge started reading either 25 psi or zero, but the check gauge light rarely came on. Two years ago the pressure sending unit failed and I had it replaced by the GT Guys in Scottsdale on the way to the LV Rally. At that time we also noted a small oil leak out of the oil pump. I had that replaced at the local Ford dealership under warrantee at the end of 2008. More about that later. I thought I had another bad sending unit and ordered another one.
Anyway, about 10 days ago I filled the car up with the usual 93 and drove about 60 miles running errands. I noticed some valve clatter if I accelerated. I thought I had gotten a bad tank of gas. I went to dinner and parked the car for a couple of hrs. That evening on the way home the engine started clattering like a sewing machine. Didn't miss, no smoke, oil pressure still going up and down on the gauge. Car didn't overheat. I limped on home (12 miles) thinking this is the worst gas I have ever put in a car. I drained the tank and purged the fuel pumps at the connector to the fuel rail. The gas did have some water in it, but not horrible. Put new gas in the car and cranked it up....same horrible clatter...sounded like the timing chain was not tensioned.
Further diagnostics ensued...
1. Pulled the plugs...no metal or residue...they looked normal
2. Checked all 8 pistons with bore scope from above....some mild areas of burned off carbon deposits from the bad gas and water. No holes, normal looking hone markings.
3. I pulled the valve covers...no displaced springs or followers. There was oil present on the cams etc. We did however note that some of the hydraulic lifters were not pumped up with oil. Reaching inside the front engine cover, the R side timing chain was also slack. Hmmm.
4. Put the car on a lift and cursory inspection with the pans off showed no signs of an oil leak. I drained out the engine oil and all 9.5 qts were there. The oil was very black. Let it sit overnight and decanted off the top stuff. There was some non-magnetic "sparklies" in the oil...almost microscopic...probably aluminum. ? if from the chain slapping the timing chain cover. The oil filter had no metal chunks in it.
5. At first I thought the oil pump and oil pump belt looked OK. Surprisingly, the belt was slack but on the pulleys and tensioner. ? had the tensioner failed or loosened.
6. I pulled the cover off the oil pump and the pulley on the pump was spinning freely! A bunch of metal dust fell out. Pictures of the intact pump and the pullley off the pump are below. The splines of the sintered pump pulley are totally gone. We pulled the pump apart and the internals look normal...it rotates freely without binding.
At this point I think my oil pump pulley was failing all along....slowly chewing up the splines. When it finally started freewheeling, the oil pressure dropped and this led to valve and chain clatter as the lifters and chain tensioner are hydraulic. We will pull the rod cap and main bearing cap at the farthest point from the oil pump. I have pulled the oil pan....no metal debis... and the cylinder walls look OK from below also. Nothing looks bad visually. Crank looks OK as best as I can tell. If there is no bearing scoring...maybe I dodged a bullet. The oil took all the heat for sure. A testament to synthetic oils.
Several questions/issues arise...
1. How did the pulley fail? The locking nut was on tight. There are no splines whatsoever inside the pulley. The pump is not fozen up itself or the belt most likely would have failed.
2. Maybe the pulley was installed improperly when my pump was replaced under warrantee. Maybe a broken tooth on the splines. The pulley is usually pulled off and placed on the new pump shaft, as best as I can tell.
3. Is there a better aftermarket pulley out there...billet? The sintered metal splines failed completely...powdered, pulverized.
4. Assuming the bottom end of the motor looks OK, once the new pump/pulley is installed...other diagnostics....check compression, leak down?
5. Anyone else seen a oil pump/pulley fail this way?
6. Doubt bad gas had anything to do with this, just coincidental?
Sorry for the long winded story. Thanks to Rich for his time on the phone trying to figure this out.
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