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Old 09-19-2016, 10:50 AM   #1
Zener424
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Default Camshaft timing gear rattling noise

I have a stock engine that I rebuilt using a Bill Stipe camshaft and a Dan McEachern aluminum timing gear with matched drive gear. In addition, the thrust plunger and spring are new. I get an erratic rattling noise that appears to emanate from the upper end of the engine. I've used several recommended methods to try & diagnose the problem. I discovered that if I remove the timing pin and insert a plastic wall anchor in the hole up against the timing gear, the noise goes away. Figuring it was a loose gear or broken/weak thrust plunger spring, I removed the timing gear cover and replaced the new spring with a used spring that appeared stronger. I also made sure the camshaft gear nut was tight. I still have the same symptoms. I ordered a new spring and I will be borrowing a spring tester to check for 35 lbs. strength. I'm wondering however if this could be something else because my thoughts are that I'm not pressing on the center of the gear, but the side of the gear possibly changing the dynamics, cocking the gear, or maybe absorbing some other camshaft/lifter related noise. Does pressing on the camshaft gear through the timing hole and stopping the sound definitely indicate a thrust plunger spring problem?
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Old 09-19-2016, 11:30 AM   #2
George Miller
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Default Re: Camshaft timing gear rattling noise

Sounds like your gears do not have enough clearance between the teeth. Did you check the play between the gears. Some times they do not get the mains on the original center line.
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Old 09-19-2016, 11:35 AM   #3
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Default Re: Camshaft timing gear rattling noise

George, thanks for the reply. Would that be not enough clearance (tight) or too much clearance (loose)? In your opinion what effect is the plastic anchor having on the gear when I push on it?
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Old 09-19-2016, 11:37 AM   #4
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Default Re: Camshaft timing gear rattling noise

I'm thinking along the same lines as George, except it sounds as there is too much clearance to me, maybe.
The cover has to come off to check that though. It should be in the .004"-.006" range and anything over .010" should/could/will be noisy. Just use feeler strips between the teeth.
The common method for checking the timing gear for the cause of a front motor noise is to put pressure against the camshaft gear.

Last edited by Patrick L.; 09-19-2016 at 03:18 PM.
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Old 09-19-2016, 11:46 AM   #5
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Default Re: Camshaft timing gear rattling noise

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Originally Posted by Zener424 View Post
George, thanks for the reply. Would that be not enough clearance (tight) or too much clearance (loose)? In your opinion what effect is the plastic anchor having on the gear when I push on it?
Of course it is just a guess, but when gears are to tight they want to climb on each other. That would cause the cam to come forward and hit the cover. That is why the plastic works. But they could be to loose, but unless the plastic is putting pressure on the cam gear it would still rattle.

You need to take the cover off and check the clearance.
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Old 09-19-2016, 06:33 PM   #6
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Default Re: Camshaft timing gear rattling noise

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Quote:
Originally Posted by Zener424 View Post
I have a stock engine that I rebuilt using a Bill Stipe camshaft and a Dan McEachern aluminum timing gear with matched drive gear. In addition, the thrust plunger and spring are new. I get an erratic rattling noise that appears to emanate from the upper end of the engine. I've used several recommended methods to try & diagnose the problem. I discovered that if I remove the timing pin and insert a plastic wall anchor in the hole up against the timing gear, the noise goes away. Figuring it was a loose gear or broken/weak thrust plunger spring, I removed the timing gear cover and replaced the new spring with a used spring that appeared stronger. I also made sure the camshaft gear nut was tight. I still have the same symptoms. I ordered a new spring and I will be borrowing a spring tester to check for 35 lbs. strength. I'm wondering however if this could be something else because my thoughts are that I'm not pressing on the center of the gear, but the side of the gear possibly changing the dynamics, cocking the gear, or maybe absorbing some other camshaft/lifter related noise. Does pressing on the camshaft gear through the timing hole and stopping the sound definitely indicate a thrust plunger spring problem?
This generally indicates a loose cam gear.
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Old 09-19-2016, 08:25 PM   #7
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Default Re: Camshaft timing gear rattling noise

Quote:
I will be borrowing a spring tester to check for 35 lbs. strength.
Tip: You can check spring strength using your drill press and a bathroom scale.
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Old 09-19-2016, 08:38 PM   #8
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Default Re: Camshaft timing gear rattling noise

From memory, the distance between the centre line of the crank shaft and cam shaft is 4.155" Anyone confirm this?
maybe you should check that. A friend over here had a worn camshaft tunnel machined when he rebuilt an engine intending to put in bronze inserts. The centre to centre distance was out by about 8 thou. This caused all sorts of problems so he made new inserts with 9 thou eccentricity. All good and smooth now.
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Old 09-20-2016, 05:45 AM   #9
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Default Re: Camshaft timing gear rattling noise

Katy, interesting tip: "Tip: You can check spring strength using your drill press and a bathroom scale."

When compressing the spring, how far do you compress it to determine if it meets the spec? Completely compressed or some specific distance?
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Old 09-20-2016, 08:57 AM   #10
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Default Re: Camshaft timing gear rattling noise

let us know how you make out
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Old 09-20-2016, 12:34 PM   #11
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Default Re: Camshaft timing gear rattling noise

Quote:
When compressing the spring, how far do you compress it to determine if it meets the spec? Completely compressed or some specific distance?
Spring spec is minimum what it should be a specified length.
I don't know the spec of the length on the camshaft plunger spring, I assume it would be the installed length. Unless you can find the length or someone posts it here you would have to calculate it.
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Old 09-20-2016, 02:50 PM   #12
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Default Re: Camshaft timing gear rattling noise

tbirdtbird, I will definitely post the fix when I figure it out. I just found this thread and it seems to be identical to my problem. Unfortynately the author: SAJ, never got back with the fix. Does anyone know if SAJ is still active?

http://www.fordbarn.com/forum/showth...thrust+plunger
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Old 09-20-2016, 03:08 PM   #13
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Default Re: Camshaft timing gear rattling noise

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Originally Posted by Zener424 View Post
tbirdtbird, I will definitely post the fix when I figure it out. I just found this thread and it seems to be identical to my problem. Unfortynately the author: SAJ, never got back with the fix. Does anyone know if SAJ is still active?

http://www.fordbarn.com/forum/showth...thrust+plunger
He just posted on 9/17/2016.

Bob
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Old 09-20-2016, 04:49 PM   #14
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Default Re: Camshaft timing gear rattling noise

Yes SAJ is still alive and active. Zener, I just replied in detail to your private message.
I stripped my Schwalms engine at 18000 miles due to cracked babbitt in all rods. Replaced the still new- looking fibre cam gear and steel crank gear with a new set of aluminium and steel gears from Snyders. Backlash was very small and too tight, but everything turned nicely without a bind so I went ahead and ran it like this. It now has a lower volume, more metallic knocking at idle. It still has a drilled and tapped timing case and adjustable thrust bolt in place of the plunger and spring. I did this to eliminate the plunger from the knocking problem on the fibre gear.
So I did not fix my rhythmic-knocking-on-idle problem, but improved it and changed its tone! Since I know all is OK inside the engine, I am ignoring the knock and piston slap I can hear when not fully warmed.
Pistons had 0.0035 clearance (dial bore gauge and checked with long thin feelers in case anyone doubts my ability to measure it!!) And pistons in the Tudor engine I assembled for my wife also have 0.0035 and run silently when cold. So I am not sure why my Schwalms engine is noisier. But piston slap might be disguising cam shaft gear clatter when running, which is why I mention it.
Maybe I should have replaced the dizzy drive gear like James Rogers did in an earlier post when he found an incompatible and knocking combination of cam and distrib. gears.
Recently we took out a broken fibre gear from a friend's phaeton and put in an aluminium gear. It was noisy so it was replaced by a woven fibre gear (Not A Macerated one!!!) and is now silent. My Alum. Gear is about as noisy as his was, but only audible as a rhythmic metallic knock at idle. It goes away when I replace the timing pin with a threaded polythene bolt pressing on the timing gear and loading it up both longitudinally and tangentially from friction
Not much help in my final analysis which is why I did not post a follow up.
SAJ in NZ
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Old 09-20-2016, 05:12 PM   #15
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Default Re: Camshaft timing gear rattling noise

One cure for any problems with the plunger spring is to machine up a spacer to fit inside the plunger to ONLY allow about .005 end float ,that will eliminate any noise from that area.
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Old 09-21-2016, 09:50 AM   #16
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Default Re: Camshaft timing gear rattling noise

Quote:
I also made sure the camshaft gear nut was tight.
Even w/the nut being tight, did you check that the gear is tight on the camshaft?

As James Rogers said in post #6, (answering to,"Does pressing on the camshaft gear through the timing hole and stopping the sound definitely indicate a thrust plunger spring problem?") This generally indicates a loose cam gear.
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Old 09-23-2016, 06:40 PM   #17
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Default Re: Camshaft timing gear rattling noise

Here's an update:

Timing gear backlash is .003.

Records from the rebuild indicate the center line of the crank shaft and cam shaft is 4.156".

The timing gear is tight on the shaft.

I received a new plunger and spring. There is no significant difference in the length or tension of the new spring vs. the one that was last installed.

Heard from Dan McEachern, he said he has seen this 4-5 times in thirty years with no solid explanation for it. He suggests like Lawrie that I might try an adjustable or solid cam button.

I'm tired of removing and installing the timing cover, so I have decided that tomorrow I will make an adjustable setup. I plan on threading a bolt with jam nut through the front cover, through the spring, and into the plunger that I will tighten and then back off about 1/3.

I'm hopeful, but I'm also mindful of the fact that SAJ installed an adjustable thrust bolt to no avail and till this day has not resolved his problem. I'm kind of hoping that the dynamics of my situation are different in some way and that the adjustable plunger will work for me.

By the way, I have since found three other threads from the past discussing this same problem and some seem to have achieved success with this method.

I will provide results.

Have a great weekend everyone!
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Old 09-23-2016, 08:51 PM   #18
James Rogers
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Default Re: Camshaft timing gear rattling noise

Quote:
Originally Posted by Zener424 View Post
Here's an update:

Timing gear backlash is .003.

Records from the rebuild indicate the center line of the crank shaft and cam shaft is 4.156".

The timing gear is tight on the shaft.

I received a new plunger and spring. There is no significant difference in the length or tension of the new spring vs. the one that was last installed.

Heard from Dan McEachern, he said he has seen this 4-5 times in thirty years with no solid explanation for it. He suggests like Lawrie that I might try an adjustable or solid cam button.

I'm tired of removing and installing the timing cover, so I have decided that tomorrow I will make an adjustable setup. I plan on threading a bolt with jam nut through the front cover, through the spring, and into the plunger that I will tighten and then back off about 1/3.

I'm hopeful, but I'm also mindful of the fact that SAJ installed an adjustable thrust bolt to no avail and till this day has not resolved his problem. I'm kind of hoping that the dynamics of my situation are different in some way and that the adjustable plunger will work for me.

By the way, I have since found three other threads from the past discussing this same problem and some seem to have achieved success with this method.

I will provide results.

Have a great weekend everyone!
Why don't you try a fiber gear and see if it is quieter.
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Old 09-23-2016, 08:55 PM   #19
George Miller
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Default Re: Camshaft timing gear rattling noise

Is there a chance the drive gear for the dist and oil pump has a problem. Maybe a bad gear, or not enough clearance, or broken spring on the dist drive gear.
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Old 09-23-2016, 09:17 PM   #20
Jim in S.C.
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Default Re: Camshaft timing gear rattling noise

I once had that same problem with a aluminum gear. I put a dial indicator on the outer edge of the gear and found a wobble in the gear. I found out that the gear mounting surface was out of square with the cam. I had it turned square put it back together and the noise went away. What has always puzzled me is that after paying the price for a touring cam. The cam grinder didn't check every dimension before sending me the cam shaft.
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