The Ford Barn

Floats · 10-04-2016, 10:10 PM

Hi Guys,
I need to replace a worn/noisy cam gear.
Any suggestions re aluminum, fiber or laminated? I notice that they come in STD, 003 and 005 sizes. How would one know which one to order?

H. L. Chauvin · 10-04-2016, 11:15 PM

As far as noise, and/or longevity, lots depends on:

1. The present condition of your existing crank gear, which is not mentioned; &.

2. Who manufactured your present crank gear, which is not mentioned.

3. When faced with unknowns, new non-metal timing gears may be a better temporary choice if noise alone is a factor.

4. If noise "plus' longevity is a factor, you could replace the crank gear and install a new "matching" metal timing gear, with both manufactured by Mr. McEachern.

5. Most chose the cheap route and keep their fingers crossed that they never have to get towed because a hungry 80+ year old metal crank gear with barbed wire type teeth ate an innocent new non-metal timing gear while sight seeing 150 miles from home.

Just one opinion.

Tom Wesenberg · 10-04-2016, 11:28 PM

I've used the original style cam gears in the past, but have just installed the first aluminum gear on one of my own engines. Won't run the engine until next year though, so no comment on the noise, but the standard size was a perfect fit. I spent a couple hours carefully sanding the rust off the crank gear before installing it, and I greased the gears to keep them nice and shiny until the engine is started.

Rust can quickly ruin a new gear no matter what it's made from.

PC/SR · 10-04-2016, 11:57 PM

I prefer metal just to eliminate the risk of failure per above. You can measure the lash, which should be .003-.005 by taking off the side cam gear cover and measuring the backlash with a dial indicator on a tooth and move the gear by hand. If the lash is within those tolerances, get a STD gear. Otherwise get a larger one as needed. Otherwise take a chance and get a std gear, which is probably what you have, and hope the new gear takes up the worn play you now have. .003 and .005 is quite a bit of oversize. Dan McEachern makes metal gears with less oversize.
Too much play on a metal gear and you just get a rattle noise. Too much play on a fiber gear and it will eventually fail.

H. L. Chauvin · 10-05-2016, 12:42 AM

Hi Chris,

Many things to consider in trying to answer your question; however, I forgot to mention a few other things:

a. Lots of crankshaft gear changing decisions depends on whether or not the Model A engine is out of the car, easily accessible, and easier to remove.

b. Also helps to know how long it took for your metal crank gear to dine on your fiber timing gear and wear it out enough until it made noise.

c. Hope this helps.

Lawrie · 10-05-2016, 01:54 AM

Sponsored Links (Register now to hide all advertisements)

TOO tight cam gears will also cause lots of drama,ask me .I know,Knocks and whines etc,
Lawrie

john charlton · 10-05-2016, 02:39 AM

The cam gear in my 31 coupe was very noisy . The noise turned out to be that the old style gear which had the metal centre had parted company with the fibre outer . The gear had a few chunks out most likely caused by the outer flopping about .The intact teeth showed no visual wear so I replaced it with a cheap and cheerfull "macerated" one (the only one I had in the "stores") No doubt it will wear out quicker than a laminated one but as I am 77 years old I think I will wear out quicker !!!

John in sunny Suffolk County England Also had many sunny days in Camps Bay in my youth great times on Camps Bay Long Beach . Once I paddled a tin canoe from Camps bay to Seapoint with no lifejacket but didnt tell my Dad .

Indiana A. Lover · 10-05-2016, 04:50 AM

John I enjoy your posts very much. I hope you are enjoying the late summer drives. The trees are really putting on a show with all the colors of fall. well have a good drive and I will be thinking of you! Don from Corn Fields of Indiana.

BILL WILLIAMSON · 10-05-2016, 06:04 AM

Minervas' BRONZE gear was slightly noisy, but gradually became super quiet, in about 8,000 miles.
Bill W.

H. L. Chauvin · 10-05-2016, 11:32 AM

As we enjoy the autumn of our days on earth, and at the ages of most Model A drivers today in 2016 ...... on second thought ...... if your timing gear or any other Model A item is very noisy:

A. One (1) of the fastest and most efficient "Senior Fixes" that quietens these noises is to remove our hearing aids; and,

B. Besides, most Model As have been known to outlive their owners; and furthermore,

C. Why in this world should we worry?

john charlton · 10-05-2016, 01:31 PM

The best thing for me is driving a model A over grass .Every year I attend a "steam rally" at a local country estate which is grassed parkland ,for some reason it seems better in an open car ,could be I am a little nutty!!! . For me the best looking part of a model A is the 30/31 stainless headlamp especially with the English lavender coloured lens also the 19" wheel which is close second .OK I confess I am a closet nutter !!!

John in cool autumnal Suffolk County England ,I have a North American pin oak in my garden (brought in to England by the Victorians) which is about to give me some American fall colors !!!

Floats · 10-05-2016, 03:01 PM

Thanks everyone,
You inputs are much appreciated.

Bruce · 10-06-2016, 12:40 PM

A famous -- and preferred -- Model A engine builder says that the fiber timing gear is the "fuse" in the Model A engine. If something goes terribly wrong the steel gear sheers the teeth off the soybean gear and keeps the whamback shaft from bustin' the b'jabers out of the cast iron bits. (I am speculating what might break if there was a drastic lockup.
I bought the concept and the fiber gear. I do not want to test the hypotheses on one of our engines, though.

10-04-2016, 10:10 PM	#1
Floats Senior Member Join Date: Dec 2013 Location: Mossel Bay, about 300km from Cape Town Posts: 530	Replacement cam gear Hi Guys, I need to replace a worn/noisy cam gear. Any suggestions re aluminum, fiber or laminated? I notice that they come in STD, 003 and 005 sizes. How would one know which one to order? __________________ Regards Chris Cape Town 28 Model A RPU, 29 Chevy Phaeton, 67 E Type FHC, 67 250SL Pagoda, 83 911 SC

10-04-2016, 11:15 PM	#2
H. L. Chauvin Senior Member Join Date: May 2010 Posts: 4,179	Re: Replacement cam gear As far as noise, and/or longevity, lots depends on: 1. The present condition of your existing crank gear, which is not mentioned; &. 2. Who manufactured your present crank gear, which is not mentioned. 3. When faced with unknowns, new non-metal timing gears may be a better temporary choice if noise alone is a factor. 4. If noise "plus' longevity is a factor, you could replace the crank gear and install a new "matching" metal timing gear, with both manufactured by Mr. McEachern. 5. Most chose the cheap route and keep their fingers crossed that they never have to get towed because a hungry 80+ year old metal crank gear with barbed wire type teeth ate an innocent new non-metal timing gear while sight seeing 150 miles from home. Just one opinion. Last edited by H. L. Chauvin; 10-04-2016 at 11:21 PM. Reason: typo

10-04-2016, 11:28 PM	#3
Tom Wesenberg Senior Member Join Date: May 2010 Location: Mpls, MN Posts: 27,582	Re: Replacement cam gear I've used the original style cam gears in the past, but have just installed the first aluminum gear on one of my own engines. Won't run the engine until next year though, so no comment on the noise, but the standard size was a perfect fit. I spent a couple hours carefully sanding the rust off the crank gear before installing it, and I greased the gears to keep them nice and shiny until the engine is started. Rust can quickly ruin a new gear no matter what it's made from.

10-04-2016, 11:57 PM	#4
PC/SR Senior Member Join Date: May 2010 Location: Santa Rosa, CA Posts: 1,278	Re: Replacement cam gear I prefer metal just to eliminate the risk of failure per above. You can measure the lash, which should be .003-.005 by taking off the side cam gear cover and measuring the backlash with a dial indicator on a tooth and move the gear by hand. If the lash is within those tolerances, get a STD gear. Otherwise get a larger one as needed. Otherwise take a chance and get a std gear, which is probably what you have, and hope the new gear takes up the worn play you now have. .003 and .005 is quite a bit of oversize. Dan McEachern makes metal gears with less oversize. Too much play on a metal gear and you just get a rattle noise. Too much play on a fiber gear and it will eventually fail.

10-05-2016, 12:42 AM	#5
H. L. Chauvin Senior Member Join Date: May 2010 Posts: 4,179	Re: Replacement cam gear Hi Chris, Many things to consider in trying to answer your question; however, I forgot to mention a few other things: a. Lots of crankshaft gear changing decisions depends on whether or not the Model A engine is out of the car, easily accessible, and easier to remove. b. Also helps to know how long it took for your metal crank gear to dine on your fiber timing gear and wear it out enough until it made noise. c. Hope this helps.

10-05-2016, 01:54 AM	#6
Lawrie Senior Member Join Date: May 2010 Location: Qld, Australia Posts: 4,212	Re: Replacement cam gear Sponsored Links (Register now to hide all advertisements) TOO tight cam gears will also cause lots of drama,ask me .I know,Knocks and whines etc, Lawrie

10-05-2016, 02:39 AM	#7
john charlton Senior Member Join Date: May 2010 Posts: 1,304	Re: Replacement cam gear The cam gear in my 31 coupe was very noisy . The noise turned out to be that the old style gear which had the metal centre had parted company with the fibre outer . The gear had a few chunks out most likely caused by the outer flopping about .The intact teeth showed no visual wear so I replaced it with a cheap and cheerfull "macerated" one (the only one I had in the "stores") No doubt it will wear out quicker than a laminated one but as I am 77 years old I think I will wear out quicker !!! John in sunny Suffolk County England Also had many sunny days in Camps Bay in my youth great times on Camps Bay Long Beach . Once I paddled a tin canoe from Camps bay to Seapoint with no lifejacket but didnt tell my Dad .

10-05-2016, 04:50 AM	#8
Indiana A. Lover Senior Member Join Date: Sep 2014 Location: Brook, Indiana Posts: 214	Re: Replacement cam gear John I enjoy your posts very much. I hope you are enjoying the late summer drives. The trees are really putting on a show with all the colors of fall. well have a good drive and I will be thinking of you! Don from Corn Fields of Indiana.

10-05-2016, 06:04 AM	#9
BILL WILLIAMSON Senior Member Join Date: Dec 2010 Location: FRESNO, CA Posts: 12,560	Re: Replacement cam gear Minervas' BRONZE gear was slightly noisy, but gradually became super quiet, in about 8,000 miles. Bill W. __________________ "THE ASSISTANT GURU OF STUFF"

10-05-2016, 11:32 AM	#10
H. L. Chauvin Senior Member Join Date: May 2010 Posts: 4,179	Re: Replacement cam gear As we enjoy the autumn of our days on earth, and at the ages of most Model A drivers today in 2016 ...... on second thought ...... if your timing gear or any other Model A item is very noisy: A. One (1) of the fastest and most efficient "Senior Fixes" that quietens these noises is to remove our hearing aids; and, B. Besides, most Model As have been known to outlive their owners; and furthermore, C. Why in this world should we worry?

10-05-2016, 01:31 PM	#11
john charlton Senior Member Join Date: May 2010 Posts: 1,304	Re: Replacement cam gear The best thing for me is driving a model A over grass .Every year I attend a "steam rally" at a local country estate which is grassed parkland ,for some reason it seems better in an open car ,could be I am a little nutty!!! . For me the best looking part of a model A is the 30/31 stainless headlamp especially with the English lavender coloured lens also the 19" wheel which is close second .OK I confess I am a closet nutter !!! John in cool autumnal Suffolk County England ,I have a North American pin oak in my garden (brought in to England by the Victorians) which is about to give me some American fall colors !!!

10-05-2016, 03:01 PM	#12
Floats Senior Member Join Date: Dec 2013 Location: Mossel Bay, about 300km from Cape Town Posts: 530	Re: Replacement cam gear Thanks everyone, You inputs are much appreciated. __________________ Regards Chris Cape Town 28 Model A RPU, 29 Chevy Phaeton, 67 E Type FHC, 67 250SL Pagoda, 83 911 SC

10-06-2016, 12:40 PM	#13
Bruce Senior Member Join Date: May 2010 Location: Sun City West, AZ Posts: 489	Re: Replacement cam gear A famous -- and preferred -- Model A engine builder says that the fiber timing gear is the "fuse" in the Model A engine. If something goes terribly wrong the steel gear sheers the teeth off the soybean gear and keeps the whamback shaft from bustin' the b'jabers out of the cast iron bits. (I am speculating what might break if there was a drastic lockup. I bought the concept and the fiber gear. I do not want to test the hypotheses on one of our engines, though.