View Full Version : TR2/3/3A oil pump drive shaft removal challenge on TR3

03-13-2013, 12:23 PM
Hi all,

Engine has not been run for some years on TR3B. I have removed the distributor and drive gear, and could not remove the oil pump drive shaft. My goal is to drive the oil pump directly. I poured some Marvel Mystery Oil down the shaft, and tapped the sides of the shaft. etc. Now it will lift up a ways, but I cannot remove it altogether to get to the slot in the oil pump. I am afraid to force it any further.

Any of you run into this?

03-13-2013, 12:41 PM
Haven't had that problem - does sound a little unusual - possibly the drive tang on the shaft has mushroomed a little over time? If its too tight, you run the risk of damaging the bronze bush as you pull it out. Unfortunately, I think its either that, or drop the pan, pull the pump, and take the shaft out through the bottom.

edit: if the goal is to just drive the pump, with the gear off why not carefully chuck a drill on the shaft and drive it? Run it counterclockwise. No need to pull the shaft out if that is the only goal. You will need to get the drive gear back in a good location for the distributor of course if you want to fire it up.

03-13-2013, 03:44 PM
Are you trying to remove the shaft that is driven by the Camshaft? I think you need to rotate it as you are pulling it up to dis-engage the gear on the camshaft. If you have that shaft out you then should be looking at the oil pump shaft and you should not be able to lift it at all.

The oil pump might be frozen and not allowing you to rotate the shaft to lift it out. In that case, pull the spark plugs and see if you can rotate the crankshaft by hand, if you can then you should see the oil pump shaft move as well which says the oil pump is not frozen. My guess is that the pump is frozen. By turning the crank you might free it enough to get the shaft out. Soak it well with some very thin oil if you can get it to flow down the shaft.

03-13-2013, 10:08 PM
The pump rotates freely. Referring to https://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=36459#33, I have removed part 31, and am trying to remove part 33, so i can drive part 35 with the dowel. That is how i remember it working in my spitfire long ago, and assume from what I've read elsewhere works also in a TR3.

03-14-2013, 08:01 AM
Part #35 is the bushing. That's not what has to be driven. You actually want to drive part #39, the rotor of the pump. As Randy mentioned, Just drive the shaft that you're trying to remove, and that will spin the pump. There's a slot in the pump gear that is engaged by a tang on the shaft, and yes, that tang does mushroom out a bit, and can make it hard to remove past the bushing. At least that was the case with my car.

03-14-2013, 09:24 AM
It's been a while since I removed those parts but I seem to recall that the gear and shaft would come out as a unit. They are keyed together. Having the gear out but not being able to then remove the shaft is puzzling. Does it get tight and you are not able to rotate it when you move it up a ways? Or does it still rotate freely? My guess is that the bushing (which is pressed into the block) is worn and not allowing the shaft to pull free. You may need to pull the pan and oil pump and go in from the bottom.

03-14-2013, 03:56 PM
Yeah, that is what i figured too. Yes, it moves freely, but gets tight and cant rotate it when I move it up a ways. But rotates freely when down.

03-14-2013, 04:54 PM
Yeah, that is what i figured too. Yes, it moves freely, but gets tight and cant rotate it when I move it up a ways. But rotates freely when down.

I'm still going to vote for using a drill on the existing shaft. Just be careful and chuck securely and don't let the drill slip and mar the shaft. Also, since you pulled the drive gear, make sure you don't lose track of the small key that ties it together with the shaft. You should be able to drive up the pressure with the pump, and save for a later day the issue with the shaft not coming out cleanly.

edit (again): also, you may want to check that the shaft still slots into the oil pump - you should be able to tell that by rotating it until the tang and slot lines up and the shaft drops say 1/4" down. There's a chance the tang sheared off which is why the car hasn't been run in years, and maybe why you can't pull the shaft easily.

03-15-2013, 09:47 AM
Tang isn't sheared off. thanks for all the input!

03-15-2013, 05:51 PM
To me, starting an engine when you know there is something wrong inside is just foolish. Dealing with a bent shaft or whatever is bound to be a lot easier up front than dealing with all the damage after something breaks. That shaft should just slide through the holes in the block and bushing. Even if the issue is only varnish or rust buildup on the exposed surface of the shaft, I would want to drop the pan and pump to be sure that's all that is wrong. It isn't that major a project on a TR3, just 20 or so bolts and it drops right off.

And if you are certain that there is nothing wrong inside, then just pull the plugs and spin it with the starter to build oil pressure. That's what I did with my TR3 that had been "put away wet" some 35 years earlier.

03-15-2013, 07:06 PM
Its rare I disagree with you Randall, but I'm don't agree on this one - the drive gear has already been pulled from the shaft, so getting pressure up using a drill is very easy, and I'm going to argue that it is a little gentler on the whole engine than running the starter on a long dead engine. Nothing wrong with figuring out why the drive shaft won't pull out longer term, but at least for initial diagnosis of what is there I don't see much harm.

On the TR3A project I picked up a couple of years ago, the shaft was difficult to pull out, but it did come out without tremendous work - and it was the mushrooming effect on the tang that was causing interference.

03-18-2013, 04:33 PM
I agree and have decided to pull the oil sump pan. Also, in messing around with this I found somewhat gritty residue in the casting surrounding the oil pump drive shaft. This concerns me too. Want to see what is in the oil pan. On another note, I have another "rebuilt" engine waiting in the wings from another TR3, rebuilt by the PO, never run. The PO suggested that he might have put one of the cam bearings in backwards, out of line with the oil journal holes. I seem to recall that I asked about this previously on this forum, and recall spinning the oil pump and seeing the oil flow at the rocker arms would assure me they were installed the correct way around. Can't find the thread anymore since we changed to the new software here. Thoughts?

03-19-2013, 11:32 AM
Seeing oil at the rockers only proves that the rearmost cam bearing is correctly installed. There are two (three, maybe? I can't remember) others in the block that also need to have their holes correctly oriented -- or there will be no oil pumped to the cam journals.

03-19-2013, 07:17 PM
I could be wrong, but don’t the cam bearings have an orientation hole and a bolt, so they only go in oneway.

03-19-2013, 07:38 PM
Yes, there is a hole and a bolt. But you can still turn the bearing front-to-back and have one hole line up. And as I recall, you can also line up the wrong one of the 3 holes with the bolt.