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Missing marks on auxiliary pulley?(replacing timing belt)  Rate Topic 
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 Posted: 05-27-2020 12:05 am
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A_Locomotive
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Hello. So today I started work on replacing my cars timing belt. This is my first time doing it but have run into a snag big one is that the auxilary pulley(next to alternator) doesn't have any dot(blue text in picture) on it as is mentioned in the guides i found online. So I am clueless as to how to verify it is in the correct position, the only mark it has is a little notch on the side near where the pulley is marked IN, it looks like a timing light mark perhaps but i see no corresponding mark around it it could line up with. I at first assumed this was just the mark it had in place of a dot, but when I aligned the intake and exhaust cams by turning the engine it didn't line up where the dot is shown. Which brings me to my next question. Verifying crank is at TDC. What marks are used to do this? I assume it is the little notice in the side of the V-belt pulley next to what appear to be timing marks, with the intake and exhaust alighned that notch lines right at about the top most mark(hard to say exactly through the sludge on them). So judging from my photos does everything look like its where it is supposed to be? And if so how do I verify the auxiliary pulley is in the correct spot without that mark?

Diagram showing alignment
https://drive.google.com/file/d/14zp97ObxyyKGzMYX5c849vGNjOP3nuGP/view?usp=drivesdk

Intake/exhaust pulleys
https://drive.google.com/file/d/15cCEJ6tVHAq7SX57f9hG6qzDVfdBwc5r/view?usp=drivesdk

Auxilary/crank pulleys
https://drive.google.com/file/d/15YSuPZwtVYGbuFXRkcK1_wux7DT2U5k3/view?usp=drivesdk

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 Posted: 05-27-2020 04:49 am
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discogodfather
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I had the same problem in a recent thread I posted. I eventually realized that the dizzy pulley has no real objective marks, and in my case it was simply a cam pulley.

The dizzy pulley rotates arbitrarily from the cam pulleys and the crankshaft. Depending on where your distributor is clocked, how the distributor cap is situated, it can all be quite confusing and unless you marked it before taking the belt off it can be almost impossible to get it back to the same position.

The procedure to get back on track is:

1) Line the cam pulleys up (looks like you did this, this is the TDC point)
2) Make sure the crank is at TDC (yes this is the mark on the V belt pulley)
3) Take of the dizzy cap, take not of the position of the rotor and where it's pointing
4) After ascertaining what the rotor is pointing at, trace the corresponding wire to which cylinder it fires. You want to find cylinder #1
5) If you find it pointing to anything but cylinder #1, then rotate the dizzy until it is pointing cylinder #1. This is a rough guess, you want the rotor to be close to touching the metal contact or thereabouts for cylinder #1
6) Reinstall the belt and tension it correctly

Now you have the dizzy pointing at #1 which it should be about to fire (TDC is always on the ignition stroke). Keep the dizzy adjustment somewhat loose, use a timing light, and try and start it up. Fiddling with the position of the dizzy in small 5 degree increments (both advanced and retarded) until you get it start.

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 Posted: 05-28-2020 07:30 am
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mtechwim
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The book says that the marking on the aux shaft should point towards the center of the crank bolt. I did it that way, see picture.
The finger off the ignition is pointing to cyl 1.

If you do it the right way, it will be easier to replace the belt in the future.

Another important point is the direction of the tensioner, if you turn it not in the right direction, the timing will go off, that will Lesotho happen when over tiding the belt.

It could happen that after installing Everything the right way, and after turning the engine by hand several times, that when the crank is at TDC, the cam sprockets do not line up perfectly, if the line up is more than a tooth something is wrong.

Attachment: 753203D5-1BB4-41D8-94ED-719C0CAE4F28.jpeg (Downloaded 31 times)

Last edited on 05-28-2020 07:42 am by mtechwim

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 Posted: 05-28-2020 07:42 am
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mtechwim
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Everything lined up aften mounting the belt.

Attachment: A5D53D4F-4B83-4651-9D5C-28B4D52BD053.jpeg (Downloaded 31 times)

Last edited on 05-28-2020 07:46 am by mtechwim

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 Posted: 05-28-2020 07:44 am
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mtechwim
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One pic with the crank at TDC and the cams not timed up perfectly

The belt has now been tensions and the engine has turnd over by hand several times.

Attachment: 6BE1DC48-C299-4EDC-836B-D1CD46F92593.jpeg (Downloaded 31 times)

Last edited on 05-28-2020 07:47 am by mtechwim

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 Posted: 05-28-2020 03:57 pm
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discogodfather
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Problem with going off of any objective marks on the dizzy wheel is that someone may have changed where the spark plug wires go (it's very easy to do) so lining everything up by checking where cylinder #1 is and if the rotor is about to fire that wire off is highly recommended.

When you do the job again in the future, mark the location of the dizzy on the bolt holding the Alternator in place on the top and use some nail polish or touch up paint. That saves a lot of headache getting everything re-timed.

I always like to check and line everything up myself, that way I know exactly where everything is and where everything needs to be at the correct time. Then no guess work necessary.

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 Posted: 05-28-2020 04:10 pm
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A_Locomotive
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I did the timing belt last night. Everything is lined up exactly as it originally was before I took the old belt off. Next big thing I am going to do is remove the carburetors to rebuild them. When I do I was planning on taking a look at the timing at the distributor. I havent touched a distributor since highschool autoshop but if memory serves I can just take the cap off and check where the rotor lines up right?

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 Posted: 05-28-2020 07:12 pm
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mtechwim
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Yup, no problem taking just the cap off, the cap fits ly one way due to a notch on it.

It’s easier when the carbs are removed.

I will do the carbs ( Stromberg) this weekend.

Attachment: DA9ADCCB-DC91-4B66-AA58-86B6B520C905.jpeg (Downloaded 23 times)

Last edited on 05-28-2020 07:40 pm by mtechwim

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