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Discussion Starter #1
Bad news for me. I was driving down the highway at 60 mph and my 69 396 cut out. Upon further inspection I found my distributor rotor not turning. I'm not an expert but I am going to pull the distributor out tonight and look at it. Any tips?
 

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Well I would pull the coil wire and manually rotate the crank to cylinder 1 TDC then mark position before you pull the dizzy.


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Discussion Starter #3
Ok, I'll do that. Thx. Any guess of what the prob may be? Distributor, cam, timing chain? If it's not something easy I may have to take it to a shop because I have no place right now to work on it. Sucks, bad timing. No pun intended.
 

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it could be the pin that holds the gear on broke, came out {unlikely)
could be distributor shaft broke. had that happen in a 62 chevy II
could be the cam broke. had that happen in a 64 impala
could be the a fiber timing gear lost all its teeth. had that happen on a 73 monte carlo
good luck hope it is something easy
 

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You can get the #1 piston up on TDC. You say the rotor is not turning. Can you turn the rotor by hand in either direction? You should have to turn the distributor counterclockwise to pull it out. You will not know what happened until you get the distributor out. I could guess all day long. If the rotor does not turn but it can be turned by hand in either direction I would say the sleeve on the oil pump shaft is broken. http://www.jegs.com/i/Moroso/710/97041/10002/-1?parentProductId=745520 Look at the picture, if that sleeve is plastic it can get brittle and just break. The pin could have broken in the metal sleeve, like I said I could guess all day.
 

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I am not sure I understand your problem. The rotor is not turning!! Did you remove the cap and crank the engine to determine the rotor was not turning? If so, don't bother trying to find TDC until you figure out why the rotor is not turning.

The distributor is driven off the cam. There are only a few reasons the rotor is not turning.

1. Pull the distributor and see how the gear looks. The oil pump is driven off the cam/distributor. Make sure your gear is not stripped.

2. Check the roll pin that holds the gear on the shaft. Its rare, but the pin can shear and it will look OK. Hold the rotor and try to turn the gear. If the gear turns while holding the rotor the pin is bad. Replace it and then rotate the engine to TDC. Re-time and your good to go.

3. If the gear is OK you have a bigger problem. Sorry to say you will have to take it apart to evaluate the problem.

Good Luck'
Mike
 

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If the rotor is not turning while the engine is turning over, there is no need to mark where it is pointing before pulling. Assuming one chance for every one degree of distributor adjustment, you only have a 1 in 360 chance of it being right anyway.
You WILL need to put the engine at tdc, but it doesn't matter if you do it before or after pulling the dist. as long as it is at tdc when you install it.

Several possibilities:

1. Timing chain
2. Dist gear sheared,
3. Camshaft broke
4. Distriburor shaft broke (unlikely).

Pull the distributor. You will know immediately if the gear sheared. Twist the gear while twisting the rotor in the opposite direction.
If the gear looks ok and it passes the twist test, pull a valve cover. Rotate the engine and see if rockers are moving. If no rockers are moving, the timing chain and gears need replaced.

If rockers are moving, see if the ones in the very back are moving (#7 or #8 depending on which cover you pulled).
If front rockers are moving and back ones aren't, your cam is broken. Not common, but it does happen.

Good luck.
 

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Discussion Starter #8
Yes when cranking the engine the rotor does not turn. It did not turn by hand either. I'll pull it out tonight and if it's ok I'll pull a valve cover and check that out too. I'll post what I find in case anyone is interested. Thx.
 

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Everyone,,,,, is interested, be we sadists or masochists.
This is never good. The distributor is driven by the cam, the cam by the timing set, the timing set by the crank. Which failure are you going to root for?:sad:
Of course most failures cause additional damage too. Hopefully it was no more than a sheered distributor gear. But that still means a tear down to get to all the scattered pieces. Sorry. And the timing gear failure that lets the cam stop when the crank turns? Boy that's hard on valves, rockers, pushrods and all the stuff moving with and near them.
 

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The fact that the rotor does not turn while cranking AND that you can't turn the rotor by hand pretty much eliminates a broken distributor shaft, a broken roll pin on the distributor drive gear and sheared teeth on the cam and/or distributor drive gear. A broken camshaft would do what you describe but until you pull it apart one can't be sure. Based on the information given thus far, seems like a broken camshaft is the most likely cause unless I'm missing something?
 

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Discussion Starter #11
Pulled the dizzy and the brass gear that turns the dizzy is partially stripped. Hopefully a new dizzy will fix the prob. I will change my oil too.
 

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Discussion Starter #12
I pulled the gear off the shaft after punching out the pin. It's brass. Makes sense to me so other gears don't get destroyed. Are they always brass? I'll try to find one at a parts store out here. Hawaii can be tuff to find parts sometimes. May have to order on-line. $50 on-line at Napa.
 

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I pulled the gear off the shaft after punching out the pin. It's brass. Makes sense to me so other gears don't get destroyed. Are they always brass? I'll try to find one at a parts store out here. Hawaii can be tuff to find parts sometimes. May have to order on-line. $50 on-line at Napa.
The material that the distributor gear is made from depends on the material the camshaft is ground from (billet vs cast, etc.). Just make sure you get a gear made from the correct material.
 

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I am glad to hear you found the problem and its a relatively easy fix. Did you replace the distributor at some point in the past? If its a GM part, buy a gear from GM. They make a melanized gear that will not get eaten up by the gear on the cam.

If its an aftermarket distributor see if you can find a melanized gear that will fit the shaft. I think MSD has a larger shaft than a GM unit. You should call the aftermarket manufacturer and see what they suggest.

They have tried to get away from brass for the reason your experiencing.

Good luck
Mike
 

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Discussion Starter #15
Yeah I was kinda wondering about this brass gear. I'm not sure if that is normal or not. I don't want to put a gear in there that could damage my cam. What is melanized? Can that damage my cam? I don't want to put a gear in there that could damage the cam. The distributor serial number reveals that it is a delco remy 1969 distributor but I don't think it was the original for the car. It looks like it came out of a 69 327 Camaro and my Camaro has a 396/375 now. Maybe the big block 396/375 requires a stronger gear?
 

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Somebody put a bronze gear on your distributor. Factory GM distributors did not come with a bronze gear. Does your car have a roller cam? How many miles are on the motor? I've run a bronze gear for years. Back when my car was a daily driver I would change the gear once a year, about 3,000-5,000 miles. They had some wear on them but they were nowhere close to being shot.
 

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Discussion Starter #17
I don't know what kind of cam was put in there. I bought the car restored. An eng shop rebuilt the eng which has 2,000 miles on it. I don't know which eng shop. I think it has a beefed up cam.
 

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I don't know what kind of cam was put in there. I bought the car restored. An eng shop rebuilt the eng which has 2,000 miles on it. I don't know which eng shop. I think it has a beefed up cam.
A bronze gear should last much longer than 2,000 miles. I read some of your other posts. Sounds like your motor is pretty much stock. I doubt there is a billet roller cam in it. To be sure you could pull the intake. I would put a new cast gear on it and check the gear engagement with the camshaft.
 

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not brought up yet the dist. uses no power the oil pump runs on the gear, pump can draw a lot of power, and eat the gear
 

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not brought up yet the dist. uses no power the oil pump runs on the gear, pump can draw a lot of power, and eat the gear
Yes, if they put a high pressure oil pump in this motor it could explain the distributor gear wear. :beers:
 
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