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Timing gear: Aluminum? Nylon? Generator gear problem
Posted: Tue Apr 07, 2020 8:28 am
by Mark Nunn
I discovered when I removed my timing cover that the engine in my ’26 has a fiber timing gear. While its teeth show little wear, I really don’t want to use it since I have a generator. I have seen enough ugly photos in past threads of destroyed fiber gears. At least my crankshaft gear looks new. I would like to read your opinions on the gears that are currently available.
My first thought was to get an aluminum gear. I ruled out the need for bronze since I have a stock engine with no need for higher strength gears. The vendors also sell nylon gears that come with modified cam nuts due to thicker material. These are available in a standard version and 7.5 degree advanced for more low-end torque. I have never driven my car on the road but I live in a hilly area so a slight torque improvement for no extra cost is appealing. I did not find 7.5 degree advanced aluminum gears but assume one could be modified for a price.
Are there advantages or disadvantages to using nylon? I assume that the thicker gear body is due to the lower strength of nylon compared to aluminum or fiber.
Is there really any performance to be gained from an advanced gear? I am certain that my worn out engine doesn’t have a modern advanced cam. The last time it was rebuilt or apart was no later than the 1980’s.
The good news is that my oil distribution tube is clear, which was the reason I removed the timing cover in the first place.
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Tue Apr 07, 2020 8:45 am
by Philip
i bought one of those nylon gears and once you get it in your hand you wont want it in your
engine. get the aluminum one it can be had in 7.5 advance or regular i bought the reg and drilled it myself for 7.5 advanced
i could not tell much difference. philip
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Tue Apr 07, 2020 10:51 am
by Steve Jelf
Granted, it was a Chebby, but I had a very bad experience with a nylon timing gear. The excuse for nylon is that it's allegedly quieter than a metal gear. Come on, we're talking Model T here. Noise is part of the show, especially when the alternatives carry an increased potential for costly failure. I will go with bronze, aluminum, or good original.
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Tue Apr 07, 2020 10:58 am
by Scott_Conger
Mark, an advanced gear will give you a little more torque at lower speed, but if the cam is worn, you might not get a noticible boost. That said, Chaffin's performance cams already have that advance designed/ground in, so make sure if you go to an advanced gear, you're not putting it onto one of their cams. their cams are fine...they just don't need the gear. I think a Chaffin's cam, or an advanced gear and Stipe performance cam are two nice things to do for an engine.
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Tue Apr 07, 2020 9:35 pm
by Mopar_man
This is the one that I'm using. The one on the car is fiber.
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Tue Apr 07, 2020 11:04 pm
by Dennis Prince
I have run all different kinds of cam gears and never had a problem with any of them. They ran fiber cam gear on Chevy 6 cylinders for years and there is a lot more stress on them than a Model T. The only reason that I think of that a fiber or a nylon gear would give a problem is if when the main bearings were poured the distance between the crank and cam was not set right, in that case a aluminium, steel or bronze gear will take more abuse.
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Tue Apr 07, 2020 11:20 pm
by Alan Long
I’m with Mr Jelf. Original or Aluminium. I also have great confidence with a product that has the Manufacturers name
Clearly and proudly embossed on the part!
Alan
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Wed Apr 08, 2020 7:47 am
by Joe Bell
The best on the market are DMC gears, you pay more for them but a whole lot quieter then the others, they are cut on the same machine so the gears run smoother. I like to show people the others out there and let them run the two sets together and they sell them selves from how smooth they are! Just my thoughts on this one.
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Wed Apr 08, 2020 10:37 am
by Les Schubert
Dennis totally nailed it by my experience. The fiber cam gear in my 27 is 40 years and 25,000 miles old.
Mind you I think I may have been the person that came up with using a “spacer link” when line boring and I also carefully “stack the gaskets” when installing the generator. So the front of my T engine is quiet.
Some guys like them to rattle and that’s their business!! All good by me
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Wed Apr 08, 2020 11:05 am
by Mark Nunn
Thank you for the great input. The fiber gear in my photo has a different shape than the damaged gear Steve Jelf showed in an older post. Mine also has "FORD" in raised letters that I have not seen in older photos. That may support a previous thread that suggested there were different types and qualities of fiber gears. Is the "FORD" version better or worse? I don't know so I intend to use aluminum unless someone can convince me to reinstall the fiber gear.
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Wed Apr 08, 2020 11:12 am
by Les Schubert
Mark
I will not try to convince you. Your car, your money, quite honestly not a terribly expensive item. You have it apart and there appears to be a noticeable amount of wear.
All the best
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Sat Apr 18, 2020 9:02 am
by Mark Nunn
I'm getting ready to install an aluminum timing gear. Should I use anti-seize? I will have the engine rebuilt at some point and I don't want to creat a problem that can be avoided.
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Sat Apr 18, 2020 10:29 am
by RajoRacer
Anti-seize on what - the large gear retaining nut ? I use blue Lok-tite.
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Sat Apr 18, 2020 10:33 am
by Mark Gregush
My story and take on Nylon gear; First my engine was at the time never fully rebuilt, I was running original babbitt in the block, re-babbitted caps, polished crank, re-babbitted rods, bored 40 over, re-ground cam with no advance just higher lift, nylon 7.5 advance gear with new gear on crank, stock head. Ran that way for many years.
On a tour I was going along up a grade in Warford underdrive Ford low at a high RPM and when I went to shift into Warford direct/Ford high was turning at too high RPM and lost the center main. The car still ran and was able to load on/off the trailer.
When I got it home and pulled the engine down what I found was there were some missing teeth on the cam gear and some were fractured but not broke off. There was still enough valley between the teeth to engage the crank gear so the engine still would have/did run. I did find a few broken tooth tops in the crank oil holes which may have been the cause of the center main giving out from lack of oil or it was just its time for the babbitt to go, don't know.
My thinking is that the gear would have been still going except I stressed it way past norm shifting when I did it at too high of RPM.
Re fiber gears; Model A run them, but there are two types. Macerated gear which is made up of short compressed fibers mixed with binder, they don't last long. The other is laminated, made up of layers of woven material compressed with binders, the best type of fiber gears in mine and others OP, still used today. The reason I didn't replace the Nylon gear when I rebuilt the engine was I was going to put the Chevrolet over head on so went with aluminum gear.
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Sat Apr 18, 2020 11:07 am
by Mark Nunn
Steve, I was thinking about using anti-seize on the cam surfaces that contact the aluminum gear. That would be the gear bore and in the two locating holes. I am concerned about corrosion between the steel cam and aluminum gear.
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Sat Apr 18, 2020 11:24 am
by Norman Kling
To add a few words to what the others have said:
Unless you know what camshaft you have in the car, you should use a stock advance gear. If your cam might have been ground for advance and you also use an advanced gear, you could overly advance and cause some problems with valves opening or closing too soon.
If the engine is quite worn, just leave the existing fiber gear which looks good in the picture, and then when you rebuild the engine at sometime in the future, you can replace both cam and gear with an advanced version of either the cam or the gear. According to your first post, it looks like you live in Nebraska. If so, what you call "Hilly" is not much. And to advance the cam might even lower your top speed performance.
If you replace the gear, I would recommend either aluminum or brass.
Norm
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Sat Apr 18, 2020 11:31 am
by RajoRacer
I believe that would be a prudent position to take for anti-seize - I've never witnessed any corrosion between the cam & any gear material & I've torn down dozens of T blocks.
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Sat Apr 18, 2020 12:05 pm
by Steve Jelf
... what you call "Hilly" is not much.
Depends on where you are. It's not all flat.
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Sat Apr 18, 2020 5:56 pm
by Norman Kling
That looks like good Ruckstell country. I guess it is hillier than I thought. I have been all the way through Kansas, but only up through the east part of Nebraska toward Iowa and Minnesota. I just thought that everything from eastern Colorado to the Mississippi was flat.
Norm
Re: Timing gear: Aluminum? Nylon? 7.5 degrees advance?
Posted: Sun Apr 19, 2020 6:14 am
by A Whiteman
Depends on where you are. It's not all flat.
True, I would call that one "gently rolling"!
Re: Timing gear: Aluminum? Nylon? Generator gear problem
Posted: Wed Apr 22, 2020 1:16 pm
by Mark Nunn
I installed a new standard aluminum timing gear and it's time to check generator gear clearance. My new problem is the gear is slightly loose on the generator. Does anyone have advice or solutions to tightening the gear? Is there an undersized gen gear? The pin through the gear isn't set very well. Maybe setting it more aggressively will help. I'm starting to believe I will never get this car on the road.
Re: Timing gear: Aluminum? Nylon? Generator gear problem
Posted: Wed Apr 22, 2020 1:35 pm
by jab35
Mark: Remove the gear and check gear bore and shaft fit, if that's loose, a new pin isn't the cure. Also check the shaft and gear holes with a new pin. If the shaft and gear bore fit is acceptable, but the pin is not tight in both gear and shaft, you need to ream out the holes and install an oversize pin. That gear needs to be solid on the generator shaft, best, jb