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Overdrive Oil Pump Installation Question

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bj8bn2

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Need some guidance on installing the OD pump with the OD unit still in the car. I lined up the two screw holes with long 10/32 screws and the flat side of the piston/roller was pointed toward the back of the car (as the manual instructs) but the pump was very difficult to drive all the way home - so I stopped the installation. The manual says "tap it in" but this is requiring more than tapping. How much force should it take to install the pump? Are there any secrets to make sure the piston/roller are aligned properly? I can't see the "steel pin" in the casing that supposed to keep the roller from rotating.

Thanks, guys.
 
Keoke, I think the wire trick works when the OD unit is separated from the tranny. In my case the units are still together and in the car. My concern is the excessive force that seems to be needed to drive the pump in and how to make sure the roller head is aligned properly when driving the pump in.
 
It should tap in without too much force. I had the side cover removed when I worked on mine so you can see that it is going together correctly (that's if I'm recalling correctly...).
 
Yes Jon you need that side cover off.
 
Thanks guys. The side cover is off (to remove pump check valve, which needs to come out before pulling or installing the pump). I need to get better glasses, more light and maybe a mirror to see how it's going together. The manual is so vague about this that it must not be a big deal getting it right.

Do others agree that the pump should just tap in without too much force?

Thanks,

August
 
It took me some hefty tugs with a substantial slide hammer to remove one, so I'd expect it would take some effort to put it back. My recommendation would be to put the pump piece in the freezer overnight__or use some dry-ice, if you have a handy source nearby__and maybe put some heat on the aluminum case with a high-intensity lamp (open flame doesn't seem like a good plan...).

Take two (2) aspirin and go to bed, then try again in the morning! ;)
 
Oddly enough, I actually have the Mowog proper puller for the oil pump. I easily pulls the oil pump out and now that I think of it I might have spent some time with a heat gun before I pushed it back in and I definitely do remember being excruciatingly careful that it went in smoothly and using a mirror to inspect the roller fork as it went in because mine had been shoved in backwards and the initial issue I determined was that the oil pump shaft was bent and once the cam pushed it down it did not return and I thus had no oil pressure.
 
Randy, Jon - great ideas. I'm hoping the dry ice will freeze the roller piston in place so it doesn't rotate when I install the pump. That's my biggest worry. Heat lamp overnight, for sure. Thanks, guys. I'm on it!
 
Here's a quick up-date. The dry ice on the pump and heat on the OD unit worked really well (thanks for the idea, Randy). I put a little grease in the pump body before freezing and that held the pump plunger in place as I tapped the pump in. Turning one wheel forward (with the other held in place) showed that the pump was moving freely. I installed new springs and ball valves in both the operating valve and the pump valve. There was already a washer in the accumulator piston spring so I did not add more (but should have). Buttoned it all up and checked the oil pressure, which showed 410 lbs with cold oil and about 400 lbs when the oil warmed up. The manual says 450 - 500 is needed (should have added more washers to the accumulator spring and perhaps a think washer to the pump valve). As most of the articles on the internet say, adjusting the operating value using the procedure in the manual does not necessarily work. I tried to use a dial gauge to ensure the ball is lifted 1/32 off the valve seat but my apparatus could not keep the dial gauge steady enough while engaging the solenoid so I did a little interpellation and it now seems to work fine. The shifting is firm and pressure holds at about 400 lbs. Got a little more work to do and then off the jack stands for a test drive. Thanks to all for the help.
 
Change your accumulator piston rings and you will get better pressure . Or if you really want to boost the pressure and have tire squealing overdrive shifts pull the accumulator sleeve and install the Jaguar size piston instead .
 
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