Your oil pump will fail., And it will kill your engine. |
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Your oil pump will fail., And it will kill your engine. |
Valy |
Sep 15 2011, 09:38 PM
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#1
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Senior Member Group: Members Posts: 1,677 Joined: 6-April 10 From: Sunnyvale, CA Member No.: 11,573 Region Association: Northern California |
I'm rebuilding a 2.0L and posted a lot of pictures in a different thread.
One of the pictures showed the oil pump and Jake immediately noticed that the pump failed. Went back to the engine and saw how the oil pump touched the cam gear and shred off the nits holding it. Being such an anal guy, I took same time today to understand why did the oil pump fail? The red axle in the picture above it the one that protruded through the pump cover. There's nothing that holds it in place except the friction between it and the cover! So Why does it move? This red axle goes into a cavity of the oil pump case (rightmost in the figure). The cavity is almost snug-fit to the axle but oil can infiltrate around the axle into the cavity. When the pump works, there is a bit of oil pressure in the pump that causes the oil in the cavity to push the axle out; just like a hydraulic piston. The force is small but it's constantly there. As the axle moves, more oil flows in and that keeps pushing the axle out. Over the time, that axle is pushed out of the pump cover until it starts touching the cam gear, shredding the nits that hold it. Eventually, the nits will brake or the axle will block the movement of the camshaft and something else will brake or your camshaft bearings will give due to the vibration inducted by the hits. The aftermarket oil pumps are build differently, with no axle that can protrude into the motor, making them a good upgrade to your old original pump. Make yourself a note to replace that old oil pump at the first occasion. I will even recommend to create that occasion before it's too late. |
JStroud |
Sep 15 2011, 09:53 PM
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#2
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Senior Member Group: Members Posts: 1,463 Joined: 15-January 11 From: Galt, California Member No.: 12,594 Region Association: Northern California |
This may all be true, but aftermarket pumps from what I've been reading have their problems also, mainly quality control, too much clearance causing frothing of the oil. So what aftermarket pump and how do you know it will be better. Or last, haven't found much data to support me buying one for my rebuild yet. Have posed the question here and other forums with no real solutions offered.
Good luck if you find an acceptable replacement I would be interested in hearing about it. Jeff |
Valy |
Sep 15 2011, 10:38 PM
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#3
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Senior Member Group: Members Posts: 1,677 Joined: 6-April 10 From: Sunnyvale, CA Member No.: 11,573 Region Association: Northern California |
This may all be true, but aftermarket pumps from what I've been reading have their problems also, mainly quality control, too much clearance causing frothing of the oil. So what aftermarket pump and how do you know it will be better. Or last, haven't found much data to support me buying one for my rebuild yet. Have posed the question here and other forums with no real solutions offered. Good luck if you find an acceptable replacement I would be interested in hearing about it. Jeff You have a good point. I'm looking for a quality replacement myself and will update on that. I forgot to add in the original post that The aftermarket "Type 1" oil pumps just don't have that cavity so there is no hydraulic piston effect. Those pumps have a flat cap that covers the pump. Here is an example from the web. The pictured side it the outside of engine side, where the original Type 4 pump case is designed closed. This type 1 pump has a flat cap to close it. Note that the cap is completely flat so the axle doesn't go into any cavity. |
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