Cam Gear Swap

[GLFLSTCI02]

Hello,

I am getting parts together to change lifters, breather gear, bearing and cam in my 1995 FXDS, things sound pretty good in the camchest right now and was thinking I would use the stock cam gear on the new cam.
My question is for those of you that have done this without the proper tool, just layout and a press. How hard is this going to be to get right? The cam I have in mind is the EV13 with the stock gear. Are there other cams of similar spec that for one reason or another would be easier to do this type of swap on?

TIA,
Gene

[Fugawee]

This is probably not the answer that You are looking for...but, if it was Me...I would replace the entire Cam with the Cam Gear, and Cam all set and ready to go from the Factory.
That way Your Original Cam is intact should there be any problems, or for possible Re-sale/Bartering Purposes.
I just find it easier to do it that way vs. utilizing a Press, etc.
But, Hey...that's Me.

Just a warning...if You should go looking at EV-13 Cams on Amazon, or E-Bay...be careful of the Asian Knockoff's that are less than 100 bucks.  They claim that they are Andrews, but they are not.

[Ohio HD]

I think there's an alignment tool for this, but I've never seen it. In the past I would scribe two lines on the OEM gear at the notch in the camshaft. Some gears even have the two scribe marks. You have to be accurate with the marks, as well as accurate with the pressing of the gear. I always heated the gear at 300° for 15 minutes or so. They go on easier that way. It may even drop on, I've had some that did.

[GLFLSTCI02]

I think there's an alignment tool for this, but I've never seen it. In the past I would scribe two lines on the OEM gear at the notch in the camshaft. Some gears even have the two scribe marks. You have to be accurate with the marks, as well as accurate with the pressing of the gear. I always heated the gear at 300° for 15 minutes or so. They go on easier that way. It may even drop on, I've had some that did.

Yeah Jims has a nice tool for this job but like most of them I just don't have the bucks for a one time use.  Do all cams have that same size notch in the same position as my stock cam? I like the idea of heating the gear, I wonder if I could freeze the cam and heat the gear to get a slip fit and possibly a moment to line it up before they jam?
My main reason for going this way is to preserve the backlash I have now on the stock gear set without screwing around with the pinion.

Gene

[Ohio HD]

I can't speak for all cams, but the Andrews cams I swapped gears to OEM were the same. These were late model Shovel and Evo cams.

I think if you freeze the cam and heat the gear you'll cause the gear to shrink fast. The couple that I had that dropped by hand, they tightened up really quick. You're not going to be able to take the time to align it if you do get one to drop on.

Also thinking back, I may have had the heat set higher than 300°.

[nmainehunter]

I have been doing it that way for years. I do it dry, on a press, heat and cold doesn't hurt . Scribe the gear with the notch as a reference, you can count the teeth from the scribes to the nearest mark on the gear if you need to double check. Most of my cam swaps have been with Andrews but I had a Sifton and a Crane. I've never had any problems. Just take your time.

[GLFLSTCI02]

Thanks, that's some good info there. I am going to get some dye to make the scribe easier to see, good idea to extend out to the teeth to check the timing marks on both cams. I have a 10 ton press so I think I should be okay if I have to go on/off a few times.

Gene

[Deye76]

I've had Crane, Andrews, S&S, Mackie cams in my Evo's and never changed a gear, all were quiet as stock.

[SP33DY]

The Snap-On man used to sell a Blue Point HD-485 Cam Gear Alignment Tool. It's simple to use and cheap, if you can find one.

[Dan89flstc]

Heat the gear to 300F.

Wrap the cam in paper, put it in a box of dry ice for at least an hour (the paper keeps the ice from sticking to the part).

The gear will drop on and you will have several seconds (plenty of time) before the gear is tight on the shaft.

[GLFLSTCI02]

The Snap-On man used to sell a Blue Point HD-485 Cam Gear Alignment Tool. It's simple to use and cheap, if you can find one.

Yeah that looks like a nice tool and not too expensive, but they are as you say not easy to find.

Heat the gear to 300F.

Wrap the cam in paper, put it in a box of dry ice for at least an hour (the paper keeps the ice from sticking to the part).

The gear will drop on and you will have several seconds (plenty of time) before the gear is tight on the shaft.

I am going to give it a go using a cryogenic processor I have here, LN2 will take the parts down to -395 F but for a shrink fit you don't need to go that low. I can set it to ramp down and hold @ -200 for a few minutes and that otta do it.

Gene

[JW113]

Going to be the devil's advocate here, but...

That steel cam gear is being driven by a steel pinion gear. To keep the two from wearing against each other, it's my understanding that they are case hardened. Heating a hardened part can take the temper out of the heat treated area.

Is this really a good idea?
 

Shrink fit works great for aluminum to steel applications. I sure wouldn't do this on heat treated parts.

That said, I've swapped many a cam gear with just a press and carefully scribing the gear as described above. I'm sure the gear ends up a degree or two off, but so what? Not really noticeable. I eventually got the cam gear alignment tool.

-JW

[Ohio HD]

Annealing steel to reduce the hardness, I've been told you need around 600°F or higher. This info came from the guys that reworked my Baker transmission to help insure no stripped gears.

[JW113]

OK, sounds good. I think I tend to be a bit overly cautious with gears and heat.

cheers,
JW

[Dan89flstc]

Heating a cam gear to 300 degrees f won`t hurt a thing, the gear will see that temperature during use.

[GLFLSTCI02]

Well I just finished with the swap, no heat, no cold, one shot and done. I made a holder for install from some 3" brass rod stock cut about 2" long with the ends faced and a hole bored in the middle just a bit larger than the bushing end of the cam. This supported the gear and helped to get me started straight, in she goes and I landed smack on my scribed marks first shot.
Just waiting for a few parts that should be here Monday and back together she goes.Thanks to everyone for the useful tips.

Gene