Oil pump drive gear stuck

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67dodgedartconv

67dodgedartconv

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I attempted to install the oil pump drive gear and it is stuck too far up. This is a rebuilt engine I purchased without the drive gear installed. It is a 318 and has a new high volume pump. I purchased the heavy duty drive gear from mopar performance. Primed the oil pump with a long hex rod tool from mancini I think. Tool fit fine, not tight. Dropped the drive gear in to index it and it barely clears the bottom of the distributor hole. Tried to back it out with a screwdriver and hooked it underneath with a small 90 degree pick but no luck. Did not force it down. I guess my only option is to take intake manifold off? Then I guess I need to polish the hex end of the drive gear if I ever get it out?
20180526_150425.jpg
 
If could be the bushing for the drive is too tight. I would confirm that before I did anything. 65'
 
Sometimes/ often, the engine has to be rotated to get the hex to engage the pump, before the drive will drop in.
But I agree with Plymouth65. That bushing if new, is supposed to be reamed to fit the drive, after being installed. If this is not done, then the drive also may not engage the cam, And with the bushing now tight on the shank, You can no longer turn it.

So now you could have a total of up to three problems.
IMO, you will gave to get it out of there somehow and verify both the shank and bushing diameters.
I have been down that road and for me it was not fun. Sometimes you can walk the out by upward pressure of a hook tool, while simultaneously twisting it back and forth with a very large one-piece-screwdriver. Resist the urge to use a multiple piece set-up on a T-bar, cuz if the tip falls off............. You will be even unhappier
 
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AJ/FormS said:
Sometimes/ often, the engine has to be rotated to get the hex to engage the pump, before the drive will drop in.
But I agree with Plymouth65. That bushing if new, is supposed to be reamed to fit the drive, after being installed. If this is not done, then the drive also may not engage the cam, so now you could have a total of up to three problems.
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I rotated the drive gear so wouldn't that be like rotating engine? Bushing looks new. So I need to pull the intake, tap the drive gear out, then probably ream the bushing? Sounds like at best brass particles get in my oil. Is there a tool for reaming the bushing?
 
67dodgedartconv said:
I rotated the drive gear so wouldn't that be like rotating engine? Bushing looks new. So I need to pull the intake, tap the drive gear out, then probably ream the bushing? Sounds like at best brass particles get in my oil. Is there a tool for reaming the bushing?
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The bushing has to be reamed/burnished AFTER being installed.
But hang-on
If you can rotate the drive gear, then it is not stuck in the bushing, and that's sortof a good sign. And yes if you can rotate it, that is the same as rotating the engine.... at this point because neither the worm gear nor the Hex is yet engaged.
Normally the worm engages the cam first, then right afterwards, the pump.
You probably already know this, but I think it's worth mentioning; The slot in the top wants to be synchronized to the driverside front intake bolt with the engine at TDC compression of #1 cylinder. Because of the worm drive, that intermediate shaft rotates into place, while almost simultaneously engaging the oil pump;and for a newbe it usually takes several attempts to get this all done. The point is that this is really difficult if the I-shaft bearing won't easily enter the bushing, and even worse if it won't come out.
Find out what the problem is and fix it. If you can spin the I-shaft, then the issue is probably that the I-shaft bearing is not entering the bushing; probably..
 
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i would put a socket on the crank and turn it slightly, seeing if the cam rotation will "suck" in the shaft
 
AJ/FormS said:
The bushing has to be reamed/burnished AFTER being installed.
But hang-on
If you can rotate the drive gear, then it is not stuck in the bushing, and that's sortof a good sign. And yes if you can rotate it, that is the same as rotating the engine.... at this point because neither the worm gear nor the Hex is yet engaged.
Normally the worm engages the cam first, then right afterwards, the pump.
You probably already know this, but I think it's worth mentioning; The slot in the top wants to be synchronized to the driverside front intake bolt with the engine at TDC compression of #1 cylinder. Because of the worm drive, that intermediate shaft rotates into place, while almost simultaneously engaging the oil pump;and for a newbe it usually takes several attempts to get this all done. The point is that this is really difficult if the I-shaft bearing won't easily enter the bushing, and even worse if it won't come out.
Find out what the problem is and fix it. If you can spin the I-shaft, then the issue is probably that the I-shaft bearing is not entering the bushing; probably..
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Yes, was trying to drop gear into proper position for alignment then got the rude awakening. You lost me at i shaft bearing, you mean the just the I shaft not fully entering the bushing? I know that it is tight so far and it needs to go down another 5 inches or so to engage the camshaft gear and oil pump. Evidently made a mistake in assuming builder had burnished the bushing or else the mopar performance I shaft is slightly larger than the old stock one. If I turn it with a screwdriver there is slight resistance and I can't pull it back up. I don't want to force it down because it may not align exactly with the hex drive in the pump and ruin it. Even if it did align l think it would still be too tight to pull up if needed if it wasn't indexed correctly. To burnish the bushing I still need to get the I shaft out. At this point just don't know how to get it out without pulling the intake since it is too tight to pull up. Too tight to pull up and too tight to go down. Am open to suggestions though.
 
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Just bump the starter with a screwdriver pushing down on the drive slot. The OP never said the bushing was new and not reamed, it just looked new but brass in iron always looks pretty good. The starter will turn the cam which will turn the barely seated drive gear and downward pressure will align cam with oil pump drive. Thats what I would try. If he gets the drive gear stuck more and it still wont turn with cam motion? Then hes got other issues. Worst case is he'll pull pump and drive pump drive out with a drift. Throw the seated slot position out the door, its not important as you'll be disturbing TDC anyway bumping the motor. If that doesnt work you can turn the crank backwards to allow the cam to pull down the drive gear.
 
Make sure you have the oil pump drive for a small block. B block drives are longer.
 
Just for the record.....Some of the shaft bushings do NOT needed to be burnished. But that shaft sure does look to be at point of entering the bushing and so that is a good suspicion.

OP did it turn with the screwdriver?
 
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Take a shoe lace and tie a noose on the end. Get it over the gear and pull it tight around the drive shaft. Then pull it upwards as you turn the shaft in reverse.
 
The Mopar bushings definitely still need to be reamed.
I just checked a small block I have apart and it appears the hex tip is probably not into the oil pump hex yet, guessing the depth in the picture above compared mine below. I just had this happen on 5.9 Magnum engine too, after installing a new bushing without the burnishing tool. Normally the new bushing goes on the tool, then gets hammered into the block. Then the tool is tightened to draw it out of the bushing, burnishing the bushing to size as it comes out. Really have not seen much shavings at all. So, bend a flat piece of steel into an L-shape, clamp it tightly into some locking pliers, and gently tap it out (up). It will come out. Then get the burnishing tool or borrow one, or take the car to a shop that has one. Pound it in and drive it out. Should be good to go, but look closely for shavings before sticking the intermediate shaft in.

IMG_20180526_223443.jpg
 
mbaird said:
Take a shoe lace and tie a noose on the end. Get it over the gear and pull it tight around the drive shaft. Then pull it upwards as you turn the shaft in reverse.
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I was thinking similarly, but to get 2 loops of heavy fishing line and loop them around and put the 2 ends on opposite side of the gear, so you can 'walk' the gear and shaft up out of that tight spot.
 
Loosen the pump mounting bolts and let the shaft line up the pump instead of vice versa. Those HD shafts can sometimes
be tight , not in the bushing, but where if fits down through the block. The bolt holes have enough clearance that the pump can move around slightly.
 
mbaird said:
Take a shoe lace and tie a noose on the end. Get it over the gear and pull it tight around the drive shaft. Then pull it upwards as you turn the shaft in reverse.
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You may need two, at 180* apart.
I use a thin stainless steel mechanics wire, and twist the gear while pulling up.
 
If the gear is hitting the intake the bushing isn't aligned right and may be causing the binding.


Alan
 
Arghh! just rotate the cam via the crank! The suspense is killing me.....
 
Was the hole full of oil/grease when you tried to put the gear in?
If you cant get wires around it to pull it out maybe clean the gear face and try a good magnet, suction cup, or possibly even super glue a "handle" on it.
 
If it were me, I'd tap it in with a mallet and get it seated. See if it will broach itself. If it locks up the cam, then Id pull the pan and tap it out with a drift. Brass is not that hard. The drive itself is .4850 with the bushing area right under the gear at .4845 (on mine) so the broached size should be .4850 with mine showing .001 wear. Also the .4850 shank goes 3.6 inches below the gear then it tapers down to the hex for another 4.1 inches so if you can get it pulled, measure how far its going in before it hangs. Dont polish the hex, its not the friction point, just wipe down the .4850 shank with grease and drive it in.

Here is another post on the subject of not broaching it :"...well, thank a lot, guys. now i'm paranoid. i've installed hundreds of these things, and never had a problem with clearance or spinning. i use an unworn driveshaft to drive the bushing in, and then spin it until it spins freely. hundreds (i'm old). i knew of the tool, never never knew anyone who had it, so i always made do with what i have. i never did ream or cut the bushing. maybe that's why i've gotten away with it?..."
 
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pishta said:
If it were me, I'd tap it in with a mallet and get it seated. See if it will broach itself. If it locks up the cam, then Id pull the pan and tap it out with a drift. Brass is not that hard. The drive itself is .4850 with the bushing area right under the gear at .4845 (on mine) so the broached size should be .4850 with mine showing .001 wear. Also the .4850 shank goes 3.6 inches below the gear then it tapers down to the hex for another 4.1 inches so if you can get it pulled, measure how far its going in before it hangs. Dont polish the hex, its not the friction point, just wipe down the .4850 shank with grease and drive it in.

Here is another post on the subject of not broaching it :"...well, thank a lot, guys. now i'm paranoid. i've installed hundreds of these things, and never had a problem with clearance or spinning. i use an unworn driveshaft to drive the bushing in, and then spin it until it spins freely. hundreds (i'm old). i knew of the tool, never never knew anyone who had it, so i always made do with what i have. i never did ream or cut the bushing. maybe that's why i've gotten away with it?..."
Click to expand...
 
Ok, fellas, here's what happened. I kept turning the drive gear with a screwdriver in the slot hoping I could back it out. It had a slight to moderate resistance while doing so. I probably turned it a hundred or more times. Looks like this burnished the bushing. As I kept turning it it would drop a little farther then stay at that point then drop a little further more. Finally dropped down enough to engage the cam gear. Measured how far the top of the drive gear was from top of the distributor hole and compared it to the gear on the old engine. Distance matched so figured the hex was fully seated and cam gear fully engaged. Slot in gear not pointing at #1intake bolt at TDC so had to rewire cap for new #1 wire position. Had already primed oil pump, primed carb, started right up. Had 60 psi oil pressure at start up. Thanks everybody!
 
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