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-   -   Locating dimple on timing gear (https://www.fordbarn.com/forum/showthread.php?t=265461)

erdaviesjr 06-25-2019 10:43 PM

Locating dimple on timing gear
 

I'm having trouble locating the dimple on the timing gear. I can get very close by using a coat hanger and flashlight on #1 cylinder, but I'm never certain that I've actually found the dimple and am at TDC. I've got the rotor in the right spot, and I've tried rocking the car in 3rd gear, but I'm not sure if I've found the dimple, or if it's just the timing gear rotating. Any suggestions about finding TDC?

Ruth 06-25-2019 11:17 PM

Re: Locating dimple on timing gear
 

Sometimes the dimple is shallow. It might help to "sharpen" the point of the pin a little.

erdaviesjr 06-25-2019 11:29 PM

Re: Locating dimple on timing gear
 

I did try that, but perhaps not enough. I also tried using a punch that is much narrower. I'm wondering if the timing gear on my car has much of a dimple? If any? This was my Dad's car and he had the engine rebuilt in 2001.

31Abone 06-26-2019 12:35 AM

Re: Locating dimple on timing gear
 

Not necassary ..just take out number one plug and with a flaslight look sideways and watch until top of piston is at top dead center,set rotor to number one,done ....much easier and quicker then fords idea ..

Patrick L. 06-26-2019 05:02 AM

Re: Locating dimple on timing gear
 

Remove #1 sparkler and run the engine up to TDC on compression, Then look for the dimple. It may be easier to find this way. A light and a mirror help some fellas. Just watching the piston itself is not very accurate.

Synchro909 06-26-2019 05:12 AM

Re: Locating dimple on timing gear
 

Quote:

Originally Posted by Patrick L. (Post 1771444)
Remove #1 sparkler and run the engine up to TDC, Then look for the dimple. It may be easier to find this way. A light and a mirror help some fellas. Just watching the piston itself is not very accurate.

I agree with that.
If you're unsure that you have TDC accurately enough, do the best you can and take the car for a drive.
If it is retarded, it won't rev well and will tend to get hot.
If it's too far advanced, it will run "harsh" and you might even be able to coax it to ping.
If you can't tell after that, you're near enough.
I believe that some owners spend way too much effort trying to get the timing just right, then go and change everything when they move the lever.

Joe K 06-26-2019 05:14 AM

Re: Locating dimple on timing gear
 

If you're going to do either the dimple or the piston ALWAYS turn the engine in the direction of normal rotation.

I have lost motion too. Wife says I'm lazy. I tell her only slightly less than perfect fit but as long as motion is always forward I'm good with it.

Joe K

leo 06-26-2019 08:34 AM

Re: Locating dimple on timing gear
 

Impossible to do with the radiator in place, I used a drill and bit to make the dimple more identifiable......

Joe K 06-26-2019 08:41 AM

Re: Locating dimple on timing gear
 

Quote:

Originally Posted by leo (Post 1771497)
Impossible to do with the radiator in place, I used a drill and bit to make the dimple more identifiable......

Very true with anything other than an "angle drill."

Or you can twiddle the sharp twist drill in your fingers. This works on fiber gears. Even on aluminum gears - brass maybe not so much.

Holding the drill in a tap wrench might help get more pressure and save your fingertips.

https://static.grainger.com/rp/s/is/..._AS01?$mdmain$
Joe K

bigd1101 06-26-2019 09:29 AM

Re: Locating dimple on timing gear
 

Take out some spark plugs, put the car in neutral and turn the engine by hand with the fan or better yet, the belt. Yeah, yeah, yeah.........a no no in some circles but honestly, if your fan is not cracked, you've released enough pressure with the sparks out and you're not rocking thousands of pounds with one hand and trying to find the allusive dimple at the same time with the other. I've done this many times and found the dimple easy as pie. Then I set the timing with the New Rex wrench and bingo....good to go!


PS.....the dimple is a very subtle indentation and it's easy to miss it.


Here is an old Barn discussion on this. https://www.fordbarn.com/forum/showt...and+crank+sale

Ruth 06-26-2019 09:34 AM

Re: Locating dimple on timing gear
 

Quote:

Originally Posted by Patrick L. (Post 1771444)
Remove #1 sparkler and run the engine up to TDC, Then look for the dimple. It may be easier to find this way. A light and a mirror help some fellas. Just watching the piston itself is not very accurate.

Especially if you are 180° off... :p:p

erdaviesjr 06-26-2019 10:03 AM

Re: Locating dimple on timing gear
 

Thanks fellers. I'm going to give it another try tonight.

SSsssteamer 06-26-2019 10:29 AM

Re: Locating dimple on timing gear
 

Quote:

Originally Posted by 31Abone (Post 1771434)
Not necassary ..just take out number one plug and with a flaslight look sideways and watch until top of piston is at top dead center,set rotor to number one,done ....much easier and quicker then fords idea ..

This above information doesn't work if the piston is on the top of its exhaust stroke. And you won't find the dimple in the timing gear at this point either. The top of the compression stroke with both valves closed is where you are going to find the timing gear dimple and also set your rotor to the number one cylinder.

wmws 06-26-2019 10:44 AM

Re: Locating dimple on timing gear
 

I agree with SS except you can find the dimple at the top of the exhaust stroke. If you set your rotor there it would be 180* out.

alexiskai 06-26-2019 11:09 AM

Re: Locating dimple on timing gear
 

Quote:

Originally Posted by wmws (Post 1771549)
I agree with SS except you can find the dimple at the top of the exhaust stroke. If you set your rotor there it would be 180* out.

If your camshaft gear is placing the dimple under the timing pin hole at the top of the exhaust stroke, the gear has been installed wrong. The camshaft gear rotates at half the engine speed, so the dimple will only come around to the correct position on the compression stroke.... that's the whole point.

BillLee/Chandler, TX 06-26-2019 01:05 PM

Re: Locating dimple on timing gear
 

Quote:

Originally Posted by alexiskai (Post 1771559)
If your camshaft gear is placing the dimple under the timing pin hole at the top of the exhaust stroke, the gear has been installed wrong. The camshaft gear rotates at half the engine speed, so the dimple will only come around to the correct position on the compression stroke.... that's the whole point.


How would this be possible? The cam has two pins that align the cam gear. They are NOT symmetrical with the cam mount and the cam gear will only fit over them in the correct orientation. (I suppose there is a way for a ... to misuse a fool-proof system! :rolleyes: )



The correct method has been listed above:
1. Take out the spark plugs
2. Transmission in neutral
3. Turn the engine by hand, either with the fan/fan belt (if you're comfortable doing that) or with the engine crank or with the special wrench available from the vendors.
4. Holding the pin in place, when the #1 approaches TDC on compression the pin will drop into the dimple. Yes, it doesn't move very far but it is obvious. If you go past the dimple slightly, just back the engine a bit, it will not hurt anything.


If you don't like the "feel the dimple with the pin", look at the vendors for the little devices that will visually tell you when the dimple is encountered.

Patrick L. 06-26-2019 01:30 PM

Re: Locating dimple on timing gear
 

Quote:

Originally Posted by alexiskai (Post 1771559)
If your camshaft gear is placing the dimple under the timing pin hole at the top of the exhaust stroke, the gear has been installed wrong. The camshaft gear rotates at half the engine speed, so the dimple will only come around to the correct position on the compression stroke.... that's the whole point.




Reread the post.

The man is stating to look at the rotor position.

Strange things happen, but, its darn near impossible to install the cam gear wrong. I say near impossible because some fellas can seem to do anything.

wmws 06-26-2019 04:04 PM

Re: Locating dimple on timing gear
 

Alexiskia you are correct. The cam shaft would be 180* out which is not likely.

1crosscut 06-26-2019 06:05 PM

Re: Locating dimple on timing gear
 

I use a short smallish phillips screwdriver to find it.
The only thing a phillips screwdriver will (should) fit on an A.

aermotor 06-26-2019 07:49 PM

Re: Locating dimple on timing gear
 

When you do find it borrow some of the wives nail polish and dab some in the dimple. Makes it a lot easier to find with a mirror and flashlight next time.

John


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