# Oil pump replacement question



## tiger13 (May 4, 2012)

Can an oil pump be replaced in a 67 Le Mans 326 engine with the engine still in the car? I have a feeling the pump in my engine may be needing replacement, and I would rather not have to pull out the engine in there is any other way to get the job done. I have just not paid any attention to how close the pan is to the center link, cross member etc, I would expect that the engine would have to be lifted up off the motor mounts a ways for clearance to drop the pan, but just how much, and if it is practical is the question. It also looks like I have to pull the tranny to do a front seal, as it is leaking like a sieve from having been sitting for 20 years. Thanks for any input.


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## PontiacJim (Dec 29, 2012)

It can be done with great difficulty, but why? You need to pull the trans., so why not just pull the eng/trans out and freshen up the engine? 

I replaced the oil pump in my '68 Lemans while still in the car. Unbolted motor mounts, pulled the distributor, and raised the motor from the front as high as I could(make sure your fan won't hit your radiator or you may have to remove it). Hopefully your exhaust system has enough "play" in it so it does not hold the engine from being lifted high enough and it does not block your pan from being dropped down. Block the engine securely because if it drops when your hand is in the pan -you'll probably crush your wrist/arm, so you want someone around just in case to call 911. Then I separated the pan, but it will not pull out due to it won't clear the crank before it hits the engine frame-that's why you can't drop the pan out. You have to clean all the gasket material off the pan/block which will take some doing with a safety blade in what little space you will have. Then you want to snake your hand in between the pan and block and feel for the oil pump bolts. You will be doing this all by feel for the most part. Get a ratchet or wrench on the bolts any way you can and undo. When you drop the pump, the oil pump shaft will drop out (that's real fun to get back in and hold it up in place while you try to re-install the oil pump -but I figured it out). Pull your oil pump out. Now, when ready, re-install the oil pump shaft first. I used some wheel bearing grease on it to make it "stick" in place so it would not fall back out into the pan. Snake your new oil pump/pick-up screen back into position, don't forget the oil pump gasket, so stick/glue it on the pump first. Now while holding the pump in position, with your other hand get your bolts started and tighten as best you can. Then follow up with the ratchet or wrench. Remember, the bolts should be torqued, but you can't so do your best and hope for the best -mine did not loosen up. Put your new pan gaskets back on and use some kind of sealant so you don't take any chances that you get a leak because you missed removing some old gasket material -if it does, you just defeated the whole job. Tighten pan bolts. Drop engine back down, bolt up engine mounts, install distrib, drain oil and refill. Now if your were not careful in cleaning the old pan gasket and you got any pieces in the pan, they might not flush out and the new pump will most likely suck them onto the screen and cause some blockage. But if you did a good job, your OK.

I think that just about covers it. May be easier with the trans out and you may be able to lift it higher with an engine lift if you unhook your exhaust, and actually drop your pan -not sure. I did mine with trans in.:smile2: 

Pulling the engine -much easier. I will never change an oil pump in a Pontiac unless I pull the engine -just my opinion founded by experience.:thumbsup:


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## Chris-Austria (Dec 23, 2010)

I'm not very experienced but I just pulled the engine and it was a lot easier than I thought... I'd remove it, clean and check everything and replace the oil pump if needed. If you worry about low pressure, maybe the real problem are the bearings.. but you'll be able to check everything without any danger after the engine was removed.

Better invest 3-4 hours to remove everything from the engine and after that pull it out than work the same time without any space and just be "feeling".


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## tiger13 (May 4, 2012)

If I had help besides the wife, I would consider a complete removal, but with just her, and she being disabled, that is out of the question. The original engine had just 46,750 miles on it, but has sat for over 20 years before I restored this car. I put a new cam, timing chain, lifters in it. Had to do a valve job on it because it had blown a head gasket, that was the reason the original owners had taken it off the road back in 1994, and there was no ridges in the cylinders, and the compression was very good in the cylinders that were not dead, plugs clean every indication the engine is in good shape, and at the mileage it had, which IS correct did not warrant a rebuild in my mind at that time. The engine was clean inside when I tore it down to do the initial work, there was no sludge in the lifter valley etc. Right now, I am getting slight lifter noise at idle, and the idiot light will flicker. Off idle, light goes out, noise goes away. It does not do it all the time either. Idle is on spec.


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## geeteeohguy (Feb 2, 2008)

It is much more work to replace the oil pump with the engine in the car. Much easier to pull the engine and do it. Also much better chance of a leak free repair. BTDT. If the job of removing the engine is too heavy, have a shop do the work. Just don't try to do an in-car repair. Trust us on this one.


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## eeyore (Oct 23, 2014)

I would roll in some rods and main bearings while your in there or the flicker could return.


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## tiger13 (May 4, 2012)

Yeah, I understand it will be a lot more work to put in a pump with the engine in the car than if it was out on the stand. Have rebuilt many engines in my time and was just wondering if it was possible to do clearance wise, and if it was, was figuring on it being a real pain.
Thanks guys.


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## PontiacJim (Dec 29, 2012)

tiger13 said:


> Yeah, I understand it will be a lot more work to put in a pump with the engine in the car than if it was out on the stand. Have rebuilt many engines in my time and was just wondering if it was possible to do clearance wise, and if it was, was figuring on it being a real pain.
> Thanks guys.


Before I did anything, I would not go by the dash light. I would hook-up a mechanical gauge first to observe the oil pressure & make sure you simply don't have the electrical sending unit going bad on you -it has been sitting for a while. I would not assume a bad oil pump because the lifters are ticking. You said you had to pull the head -are you sure you don't have a loose rocker arm or two? Assuming pressed in rocker studs, did you torque the rocker arm nuts down to factory specs? Those push in studs can also pull loose and give you that ticking sound. How about a new oil filter, maybe a different brand than the one you currently have to make sure its not a filter problem? 

The oil pump replacement with engine in car is do-able(using my '68 Lemans as my experience), as I pointed out because I was in a position where I didn't have the available time, or the weather(did it outside), to do an engine removal. It may indeed be the pump, but I would check a few other things first rather than go through all that trouble only to fire it up and have lifter ticking & your oil pressure light still flickering.


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## tiger13 (May 4, 2012)

That was my next course of action PontiacJim, was to put a real gauge on it and get a true reading on the pressure. I had done an oil change on it when I did the valve job, and cam/lifters,and push rods changed and it still has the break in oil in it. I want to change it out with a new filter and oil and check the valve rockers as you suggested. It just concerns me that it will idle and that light will start to flicker, and the lifters will start making noise on one side.
Again, thanks for your opinions.


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## geeteeohguy (Feb 2, 2008)

If you're getting lifter clatter in conjunction with the low pressure light, you are probably correct in your low oil pressure diagnosis. Verify it with a gauge, and go from there. Simple and cheap to pull the motor, flip it over on a stand, replace the oil pump, and install a new set of bearings while you're at it. The thing will be good to go for another 20-40 years. Good luck with it.


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