Finally, I absolutely MUST attempt to pull my oil pump!

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johnnyusa

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I have been putting this off for years. I always keep a drip pan under my S6 because oil seeps from below the oil pump. I can't park in friend's driveways. I don't see a visible gasket between the pump and engine block but there must have been. I thought it might possibly also be beneath the distributor so I got a small gasket for that plus all gaskets for the oil pump. That should be enough.

Lifting the engine by following the MOPAR service manual says to drain stuff, remove mounts, remove throttle linkage, lift engine right front (passenger?) corner on jack stand, raise engine enough to put 8" of 2x4 between K frame and oil pan flange. Using pry bar, shift engine up and left to let 2x4 slide down to allow access to pump. They make it sound so simple but I know it's going to be some putzing. Has anyone tried this? Is there an easier way without removing the engine from the bay?

I'm attacking this 3/11/26 so any helpful advice would be welcome. Thx
 
I'm pretty sure you can just remove the pump and block the hole and a Slant 6 will run just fine. They're pretty tough.
 
Maybe you could tell us what you're workin on here? You know, they put slant sixes in a LOT of places over the years.
 
You're going to do this yesterday? How'd it go?
Seriously, sounds like you've got a good plan. Best of luck.
Sorry, 3/18! This is a 225 2bbl Super Six in a 65 Valiant Signet convertible. Here's a close up of the drips.

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I would inspect very closely higher up than the pump. It's pretty rare for them to leak. Although it looks rather new, so maybe someone didn't install it correctly. There's a lot more to it than just jacking the engine up. You need to disconnect the transmission shift linkage if it's an auto or z-bar if it's a manual. Failure to do this will result in "something" bent or even possibly broken. I would even disconnect the exhaust from the manifold. Also, if you have a fan shroud, might want to think about that, too. The engine has to be raised a LOT to get that pump out. I've done it before on my 64. It's so tight, if it had a thicker high volume oil pump on it, I wouldda been pulling the engine.
 
I would inspect very closely higher up than the pump. It's pretty rare for them to leak. Although it looks rather new, so maybe someone didn't install it correctly. There's a lot more to it than just jacking the engine up. You need to disconnect the transmission shift linkage if it's an auto or z-bar if it's a manual. Failure to do this will result in "something" bent or even possibly broken. I would even disconnect the exhaust from the manifold. Also, if you have a fan shroud, might want to think about that, too. The engine has to be raised a LOT to get that pump out. I've done it before on my 64. It's so tight, if it had a thicker high volume oil pump on it, I wouldda been pulling the engine.
Your concerns are all the same I have. I planned to disconnect the tranny and exhaust. So much just to maybe stop a leak. I don't remember it leaking until the last 10 years. There is no leak from above like the manifold gasket or spark plug area. I thought it might be the distributor so I bought the upper and lower gaskets for it in case. That pump is original when I bought this car 1991. I'm not too excited about tackling this now.
 
Ok, for these cars the FSM calls for lifting the motor a few inches with the motor mounts unbolted, and holding it there with some scrap wood to get enough clearance to remove the pump.

I have also seen the pump leak from the big bolt, and fixed it by taking the bolt out and putting sealant on the threads.
 
Ok, for these cars the FSM calls for lifting the motor a few inches with the motor mounts unbolted, and holding it there with some scrap wood to get enough clearance to remove the pump.

I have also seen the pump leak from the big bolt, and fixed it by taking the bolt out and putting sealant on the threads.
The "big bolt"? Are you referring to the pressure relief valve plug? If so, that seals with a gasket. I run the high pressure spring in all of mine and when I install those, I also discard the gasket from that plug and use a copper drain plug gasket. They always seal great and stay sealed since there is no conventional gasket to rot and start a leak. I've read what the FSM says too, but trust me, if you don't disconnect the transmission linkage or z bar, bad things can happen. Ask me how I know. LOL
 
Your concerns are all the same I have. I planned to disconnect the tranny and exhaust. So much just to maybe stop a leak. I don't remember it leaking until the last 10 years. There is no leak from above like the manifold gasket or spark plug area. I thought it might be the distributor so I bought the upper and lower gaskets for it in case. That pump is original when I bought this car 1991. I'm not too excited about tackling this now.
I also saw that you posted about oil leaking around a distributor. I said that I have both upper and lower O rings I can try if that helps. Thoughts?
 

I also saw that you posted about oil leaking around a distributor. I said that I have both upper and lower O rings I can try if that helps. Thoughts?
My thoughts are this. Stop guessing and do actual diagnosis. Inspect as I outlined. Find the highest wet, oily spot that's about in line with the oil pump and that's pretty likely the source. The distributor is just above the oil pump, so that's a possibility, but possibilities are not proper diagnoses. What kind of head does the engine have? If it has the spark plug drool tubes, then that's a huge source of oil leaks up high. An original Super Six engine has the peanut plug head with no drool tubes, but these engines are old now so parts may have been changed around. Pictures could certainly help here.
 
I don't see a visible gasket between the pump and engine block but there must have been.

Yes, there is. And there's an O-ring sealing the oil pump cover plate to the pump body; that could be leaking, too. There's also a seal on the pressure regulator valve cover plug (front of pump), and the oil pressure sender (back of pump) can leak when its internal seal fails.

While you're at it, it will also be a good idea to service the oil pressure relief valve to make sure it's doing its job, as described in these two threads: thread 1, thread 2.

I thought it might possibly also be beneath the distributor so I got a small gasket for that

There are two distributor seals. Both must be correct and in place; see here.


Is there an easier way without removing the engine from the bay?

Start with UV-fluorescent dye and a UV flashlight to pinpoint exactly where the leak is (leaks are). You might not have to lift the engine or do anything with the oil pump-to-block gasket at all.

I'm attacking this 3/11/26

Oops I'm too late lol
 
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Thanks Dan, and you're NOT too late, I meant to say 3/18. Good read on those threads. I'll take that pressure valve nut off and feel around up there to see the state of that valve and clean with crocus cloth. I bought a new Fel-Pro gasket for the nut so I believe that is now good. I have both the oil pump gasket plus outer cover gasket ready. I don't think I can take that cover off without raising the engine though, not too excited about that, as I mentioned.
 
Seems unlikely for the oil pump to block gasket to leak since those are thin paper type and usually hard to scrape off when you remove an oil pump, unless it was leaking from the start. Most likely leaking from the distributor above. Mark exactly where the rotor is pointing before you remove it, and where the bolt sits rel. to the adjustment slot. Even then, you will likely need to set ignition timing when re-installed. Note that the rotor turns as you slide it in, so need to backup the rotor tip ccw so it ends up correct when installed. Keep trying until you get it back on the same tooth it was. BTW, there is another inner adjustment slot on the underside (plate to distributor). Start with it in the middle and only fuss with it if you can't adjust timing using the accessible outer slot.

If too crowded on the right side, it is possible that the motor bracket bent (somebody jumped humps like in Dukes of Hazard?), which I suspected on my 1964 slant. Could have fixed it by adding washers, in addition to a new rubber motor mount, but I bent it straighter (using hydraulic shop press) while I had it off for painting. My guess is that the intake manifold should be horizontal if the engine is sitting correctly. I don't like the spark plug wires rubbing the inner fender, so doesn't hurt to slip split loom over them.

For O-rings in general, buy the kits at Harbor Freight (I have Nitrile, HBNR, Viton, metric and SAE). If an HBNR (usually green) fits better use it, since better quality than nitrile (black). Viton (usually brown) resists gasoline. You can buy a new timing lamp w/ clamp-on sensor for ~$40. New ones are great in that you can set a delay so to set say 15 deg BTDC it flashes when the chalk mark on the damper aligns with the 0 deg mark on the timing tab. Also displays rpm. I even use a timing lamp on my newer cars with computer-controlled ignition, not to set timing, but just to quickly verify that all sparkplugs are firing. Helped me quickly find a failed coil-pack on our 2002 Chrysler 3.8L.
 
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Good ideas, Bill. I have a Pertronics set up here and with their coil, runs outstanding. I’m not sure if marking that rotor works the same as with standard points. My friend who works with me is rather smart as a wrench and he said similar about putting the gear back where it was. I bought NOS upper and lower O rings which don’t look good to me. Hope those work.
 
Be careful here too. Should you decide to replace the oil pump, or gasket, make sure to get the right one. There's some kinda funkyness that if you mix and match the wrong things, you'll end up with an oil leak like the Exxon Valdez. I apologize, I cannot remember the details, but @Charrlie_S will know. I tagged him, so maybe he'll chime in. Also, I know our good member @Badvert65 offers a revised oil pump gasket among other really nice things for the slant 6. I tagged him too so hopefully he'll chime in as well.
 
Thanks to Slant 6 News (I have most of the issues), FABO and Slant Six Forum, I have been able to get my car to its best performance yet. Did poly motor mounts and a poly transmission mount underneath and the transfer of power from front to rear is amazing. Sure it rattles a bit with the brakes applied at a stop, but now the car takes off incredibly. I plan to follow the threads on bleeding the brake lines next (never attempted that) which will be fun. Anyone know which Russel brake bleeders part number fit my 68 four piston Kelsey Hayes? I'd like to put those in next.
 
Try to get an oil pump with 6 mounting holes (like the original) instead of 5 mounting holes. They can leak right where that 6th hole should have been drilled at the bottom portion of the casting.
 
Pulled the distributor today to check the O rings. As I suspected, there was a lot of oil by the base. The O rings were rock hard and split when removing. Fortunately, I had previously purchased both upper and lower NOS O rings and are now installed. I think this will alleviate any plans of oil pump removal now. Thanks for all the input on this thread.

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