THOSE GREAT SAGINAW WORKERS! 1985 442 PS Pump Rebuild (GM P/N 7840244)

Yup I asked about the splash shield on the cap awhile back. I ended up just spending some time cleaning my original (with no shield) and put it back on the car. No leaks and looks nice.
 
Ok, I'm a dumbazz moment # 1,423,241... :doh:

I'm weinering like a little beech about the snap ring on the back of the pump. I tried picking it out with a 90 deg. pick, didn't want to work. So lo and behold, I had a senior moment and realized why not depress the spring and take the pressure off the ring? So I get a clamp and position it to just compress the spring a bit to take pressure off the retainer ring. Slid right over into position without much fanfare and was able to remove the intended fashion of a small punch and screwdriver. :blam:

So I take the pump apart. I pull the pressure plate and ring and knocked the shaft out from the front with a non metal mallet (hold your hand behind it to catch it or it may fly out on that last tap). Inspecting the parts, they were in remarkable shape. I thought with only 60K miles on it that it would be in good shape as it made no noise and no issues, but it's darn near new looking inside. A bit of dirt here and there but mainly in super nice condition. The only issue I was initially concerned with was the "tub ring" around where the shaft seal went on the shaft. A noticable black ring which appeared as some good wear on the lip seal. I could feel it with my thumbnail. Errgh.

Turns out, it cleaned up beautifully with a touch of oil and scotchbrite massage. Can hardly see any marks and can't even detect any anomalies on the shaft surface now where the seal goes. I've seen worse on cranks. I'm sending it!

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I inspected everything and the pressure plate has extremely minimal wear, looks like it got installed last week. The vane pump ends are pristine. The 10 vanes are in super shape. No vibration marks where they sit in the grooves and they're smooth across the edges. Beautiful. Always remember to put the FLAT side to the inside of the rotor. Rounded edges go to the outside.

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I've read this about used pumps that the wavy appearance inside the pump ring is considered NORMAL. Although NOBODY has ever shown what that looks like. Welp, here it is below. Surface is glass smooth, no nicks or burrs or anything.

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Now, there's a GM reseal kit as I was discussing before, GM p/n 7848522 for this pump.

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The shaft seal that comes with it is GM p/n 7808195. This is a dual-lip spring loaded seal that is simply tapped down into the seal well. Very similar to a mini axle shaft seal. It's laughable that the seal is stamped "outside" on the outside ring of the seal. 🙂

Most kits come with a shaft seal, and as stated previously, the aftermarket seal kits also include a new main shaft bearing. My advice- if your old bearing is in great shape and basically no play, leave it alone. Even if you use a bearing installer, it'll likely beat up one end of the bearing requiring a bit of massaging to get the burrs off it for the shaft to slide through.

If you need a shaft bearing, you can always choose the interchange numbers below. Just a few. Fairly common and can be had almost anywhere for around $5-7 if you mess up the one in the kit.
15277770, 1546109, 1826167, 2537899, 26002612, 26009831, 26025959, 26025977, 26026973, 26037278, 26042234, 26043126, 32411127886, 32411128589, 5685524, 5686644, 7837492, 8078081950, 8941586930, D2VY3B592A

TIMKEN or NATIONAL 7013S
 
One thing to ensure to do is read the INSTRUCTIONS for any kit you get. There's two notes inside the GM seal kit. Sometimes there's important info in them. As this kit is designed to service a wide range of years, you gotta know what you're working on. Don't ditch the old o-rings until you compare them to the new ones. Just in case.

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Witness marks. Does it make a difference in how the pump outer ring goes in? I dunno. Haven't seen anything saying you MUST install it with this orientation or it'll break stuff. I'll take a pic of it when it goes back together, but for right now, I just wanted to show witness marks. They're sorta molded in. Some new pumps have 3 diamond or 3 dots intented into the top of the ring facing the rear of the pump. This model has 3 "teeth" molded into the side edge. Based on how I saw it when it came out, the notches face the rear of the pump when installing, and pins are located approximately 10 and 4 position. The 3 "teeth" marks are oriented to approximately the 8:00 position with the "arrow" pointing to them about at the 9:00 position. Note: The 12:00 position is the small hole for pushing out the rear cover retaining ring, so clock positions are based off of that.

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Does it HAVE to be this way? Will it cause problems if it doesn't go this way? TBH, I don't know. I do know the thrust and pressure plates make no difference in orientation. You can put them in 180 out and it still matches up.

Ironically, the CSM doesn't get into good, decent pictures of the disassembly and reassembly. They have some good notes here and there, but lacking in good detail. Not like the pumps are difficult, but if you just knocked the guts out without looking, which way would you put in the pump ring?

Note here that the CSM "instructions" show the inset with the "arrow" (more like 1/2 of an arrow) pointing toward the bottom.

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PS Pump Instructions 1.jpg

BTW, the 48 and 50 N-M torque values equate to approximately 35 and 37 lbs/ft. respectively, for those without metric torque wrenches.

But since the way mine came apart, and the way this guy's putting his back together, I'm not sure. The video of this guy rebuilding his pump shows as he knocks the guts out, his "arrow" is more at the 3:00 position and the 3 "teeth" at the 2:00 position. This pic is from when he's putting it back together as it came apart. WTF. Was his rebuilt before? Why did he need to rebuild his? I don't know. I know mine's never been apart until this week.
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Full video here:

I'm going to go by the way mine was and the CSM directions. There's always a reason.
 
From what I can see the "arrow" will point in the direction of the rotor/vane assembly rotation.

"5. Install pump ring on dowel pins with direction of rotation
arrow to the rear of the pump housing (fig. 25). Rotation is
clockwise as viewed from pulley."
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I think all that really matters is you do not install the pump ring upside down with those marks toward the front of the pump.
 
I think all that really matters is you do not install the pump ring upside down with those marks toward the front of the pump.
Thank you for confirming a suspicion I had. I was thinking about that last night. I kept looking at the ring thinking it doesn't matter how the ring "teeth" face on the clock position as long as they face the rear. It seems there's no adverse stuff could happen if the teeth were at 2:00 position. And the arrow seems stupid because it only rotates one direction anyway. But it's for the ring's rotational placement as you pointed out. As you can see, the Olds CSM doesn't 'splain things very well in that regard. It just so happened my "teeth" came out around the 8:00 position just like the drawing. I was going to put it back in the same way simply because by default, I couldn't go wrong doing it the way the factory did it since there were no real issues with the pump to begin with.

Witness marks and any arrows toward the back.
 
And I must retract my D!CKS comment to the employees at Saginaw who assembled the pump. Apparently, looking closely at the destructions in the CSM this morning, the rear cover retaining ring gap SHOULD be located near the bottom. Which, to me, is still stupid. But when in doubt, unless proven otherwise, the CSM usually has the correct info. The CSMs don't always go into the why, but there's always an engineering reason.

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So, going against the grain, I located the cap retaining ring gap at about the 1:00 position. Fugg it. If anyone else ever works on it again, they won't have to muck around with it and can get right to popping it out. I wasn't going to try and push it around to the 6:00 position again.

One thing I did was to take notice of the position of the very slight wear marks on the vanes as I took them out of the rotor wheel. As they slide back and forth while the rotor is spinning, the low pressure side of the vanes would be pushed up against the leading edge of the rotor slot. When the vanes move in and out with centrifugal force, the pressure is still high as it slides across that leading rotor edge, causing the wear marks, putting t. While everything I've ever seen on the vanes was to "install them with the flat side on the inside and the rounded edge on the outside".

Weeellllllllllllll.......seems the General didn't get the message to Saginaw in early 1985, or whenever they built my pump. Luckily I noted the positions of the wear marks to the leading side edge of the vanes. Also the worn edge was shinier than the inside edge. But BOTH edges were beveled/rounded. WTF? I even broke out the magnifying glass to try and determine if I was just seeing things. I didn't take a picture, but you could throw them all in a bucket, toss them around, and unless you knew what the wear mark positions were, you'd be hard pressed to get them in the way they came out because of this. TECHNICALLY, I guess I could have put the vanes in the other way and got new vane surfaces. But I'm not leaving anything to chance if I can help it.

After this venture, all I can say is that if you have a vise to help work on these pumps, it's well worth the trouble to use it.

I also noticed that for whatever reason, the holes in the casing were slightly pushed in around the fastener bolt holes. It didn't cause any leaks there, but I'm definitely going to straighten that out prior to reinstalling the reservoir.
 

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