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Old 12-08-2016, 01:12 AM   #61
ian Simpson
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Default Re: Camshaft timing gear rattling noise

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Originally Posted by katy View Post
You're welcome, I was hoping somebody would come up w/the correct length for measuring the spring pressure.
Do not rely on this, but memories from my long ago apprenticeship seem to suggest that springs are measured as so many pounds per inch. I.E. for the cam plunger spring it is 35lbs per inch of compression.
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Old 12-08-2016, 01:29 AM   #62
Dan McEachern
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Default Re: Camshaft timing gear rattling noise

I can almost guarantee that the gear teeth on the cam gear have been damaged by using the gear teeth to prevent rotation while tightening the cam gear nut. I will report back after seeing the gear.

Dan
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Old 12-09-2016, 01:10 AM   #63
H. L. Chauvin
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Default Re: Camshaft timing gear rattling noise

Mr. McEachern,

1. Your above reply # 62 may help some to understand why in reply # 55 he mentions:

"There is no noise now." LOL

2. Besides your mentioning further above the incorrect 100 ft.lb. Model A timing gear nut tightening myth forever "written" and recommended, it may be better to hear from you about how "NOT" to follow the forever "written" and recommended timing gear tightening method which can screw up the timing teeth for eternity.

3. My McEachern aluminum gear is totally noiseless "after" following your installing verbal instructions & recommendations.
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Old 12-09-2016, 06:12 AM   #64
Greg Jones
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Default Re: Camshaft timing gear rattling noise

As Mr. Chauvin indicates, it might be a great public service to tell the community specifically how to properly clamp the gear to tighten, so as to avoid the "rag interference" method used by so many to keep the gears from turning whilst tightening the timing gear on the cam.
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Old 12-09-2016, 07:17 AM   #65
Zener424
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Default Re: Camshaft timing gear rattling noise

Apparently the verdict is in even though the Judge (Dan) has not seen the evidence yet. However given this new information (new to me anyway), I will no longer tighten the timing gear to the mythical 100 ft lbs, I will instead use Dan's recommended 50 lbs. Also, I will clamp the gear to avoid damaging the teeth.

Unfortunately this experience also causes me to question the guidance of several well known and recommended sources.

Interesting to note, this is the fifth engine I've rebuilt, the other four had laminated gears and now it seems all were torqued too much and tightened incorrectly. Yet this one is the only one that seems to have sustained damage. Doe this same procedure need to be done for macerated and laminated gears as well, or only aluminum? How about the bronze ones? Perhaps someone else can chime in and state whether they've damaged other gears by over torquing and blocking the crank or as others have mentioned using the "rag" method?

In regards to H.L. Chauvin's comments to Dan: "it may be better to hear from you about how "NOT" to follow the forever "written" and recommended timing gear tightening method" and Greg Jones comments to Dan: "it might be a great public service to tell the community", I agree and I simply suggest that an instruction sheet with the correct procedure be included with the gear when purchased. I suppose however that this suggestion might prompt other forum members to simply say "Ignorantia juris non excusat".
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Old 12-09-2016, 10:59 AM   #66
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Default Re: Camshaft timing gear rattling noise

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Old 12-09-2016, 11:38 AM   #67
H. L. Chauvin
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Default Re: Camshaft timing gear rattling noise

After once being "written", many things in life for many of us becomes affirmative religious dogma; just like we often hear preachers begin a sentence like: "It is "written" that .........; and once "written", as Model A owners, we repeat what we read, as opposed to what we may have actually "experienced".

Our earth remained flat for several centuries until one sage protested and declared it is round.

For Model A problem solving, appears we much prefer to hear what Model A owners recently actually "experienced" .... as opposed to hearing what Model A owners formerly often read on Forums ..... so simple ...... I mean like, if one Model A owner hears sex it bad for you ..... just don't repeat it until after you experienced it!
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Old 12-09-2016, 01:42 PM   #68
Bob C
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Default Re: Camshaft timing gear rattling noise

Quote:
Originally Posted by H. L. Chauvin View Post
Mr. McEachern,

1. Your above reply # 62 may help some to understand why in reply # 55 he mentions:

"There is no noise now." LOL

2. Besides your mentioning further above the incorrect 100 ft.lb. Model A timing gear nut tightening myth forever "written" and recommended, it may be better to hear from you about how "NOT" to follow the forever "written" and recommended timing gear tightening method which can screw up the timing teeth for eternity.

3. My McEachern aluminum gear is totally noiseless "after" following your installing verbal instructions & recommendations.
He has commented before.

Dan McEachern
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Re: Model B camshaft gear nut removal
Guys- I've said it here before and I'll say it again. Don't stuff rags or anything else into the gear mesh to loosen the cam gear nut unless you are going to throw the cam gear in the trash when you take it off. If you are installing a new gear, you stand a real good change of damaging the gear teeth with this method. Take the time to clamp a block on the rear side of rim of the cam gear and let that absorb the torque of tightening or loosening the nut if you have to do it with the cam in the engine. Dan

Bob
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Old 12-09-2016, 01:51 PM   #69
Glenn C.
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Default Re: Camshaft timing gear rattling noise

You may find that the plunger bore diameter in the front timing gear cover is wore beyond a useable limit. The plunger flops around in the bore while running. Possibly someone else might know the tolerances.
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Old 12-09-2016, 03:37 PM   #70
H. L. Chauvin
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Default Re: Camshaft timing gear rattling noise

Mr. Bob C.

Thanks for posting Mr. Dan's timing gear installation recommendation in reply no. 68.

With the rounded shape of the designed contact area of gear teeth, it would be interesting to calculate and determine the pounds per square inch applied to this minute aluminum one (1) tooth gear area, on an aluminum alloy timing gear, while applying 100 foot pounds of force.
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Old 01-13-2017, 04:37 PM   #71
Zener424
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Default Re: Camshaft timing gear rattling noise

Here's an update I received from Dan on December 11, 2016:

"Hi Phil- the cam gear cam today. In checking the teeth, the contact pattern is what is referred to as "cross bearing". This means the mating gear is contacting the cam gear teeth near one face on one side of the tooth and the opposide of the tooth on the opposite face. I blued up a crank gear and check you cam gear tooth contact and it is showing contact across about 80-90% of the face so the cross bearing is not being caused by a mismatch in helix angles on the gears.

My guess is that the cam and crankshaft centerlines in your engine are not parallel and is causing the contact pattern we are seeing as well as the cam wanting to walk back and forth. I took some pictures of the contact pattern with my phone, but they are out of focus, so I'm going to take additional ones tomorrow and I"ll forward them to you so you can see what I'm referring to.

I'm pretty convinced that this is the cause of the noise you were hearing.

Just FYI- when tightening a cam gear, don't use the gear teeth to prevent cam rotation- clamp a bar or block of wood to the side of the cam gear and let that bear on the block. I suspect that many folks who experience a fiber cam gear failure do so because of damaged teeth from tightening the cam nut and letting the gear teeth react the torque.

I'll send you gear back next week- my suggestion is to use it or keep it as a spare. Thanks for going to the trouble of sending it so I could look it over.

Dan"
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Old 08-17-2018, 05:29 PM   #72
denniskliesen
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Default Re: Camshaft timing gear rattling noise

Sorry to dig up and old post but I'm having problems with mine and I intend to get to the bottom of it one way or another. Even if I have to completely disassemble to find the problem.

Now my question is and I might have missed it but ... Has anybody thought to measure for wear in the block and or journals of the camshaft. I read in Les Andrews book max allowed is .003" bearing clearance. So if you have wear .003 in the front and .003 in the back it would be possible have .006 off center if the cam were able to wobble in the bore?

Also in the Service bulletins page 342 they started to drill an oil hole in the block to the rear camshaft bearing to provide even more positive lubrication to the rear camshaft bearing. That always seems to be where there is the most contamination when you remove the valve cover. More oil, more contamination. Another one of Ford's better ideas?
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