Timing help
Thread Starter
Instructor
Joined: Mar 2011
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From: Schererville IN
Timing help
1965 365. Just replaced B1 VAC w/ B28. Also put in new brass advance stop bushing and put in new springs (Mr. Gasket, one silver, one black).
Initial timing should be 12*. I can only get about 9.5* - VAC is hitting manifold. Total timing is 36* at 3000 RPM. Timing at idle w/ VAC connected is 28*, which means I'm getting 19* from VAC. According to specs from Lars I should only be getting 8* from a B28. Getting about 10 - 11 inches Hg. Thought I'd be OK w/ initial as long as total is OK, but the reading from VAC concerns me. Problem?
Initial timing should be 12*. I can only get about 9.5* - VAC is hitting manifold. Total timing is 36* at 3000 RPM. Timing at idle w/ VAC connected is 28*, which means I'm getting 19* from VAC. According to specs from Lars I should only be getting 8* from a B28. Getting about 10 - 11 inches Hg. Thought I'd be OK w/ initial as long as total is OK, but the reading from VAC concerns me. Problem?
Le Mans Master
Joined: Aug 2009
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From: Houston Texas
St. Jude Donor '10-'12-'13
You can't get an accurate vac reading till you get your timing straight.
Sounds like your distributor is off a tooth. Try repositioning one tooth over. Afterwards you need to bump the starter to make it seat into the pump.
If you are running an aftermarket cam? You may need to re-index your distributor gear 180 degrees. That would be dimple 180 degrees opposite of rotor tip. My old comp cam was that way.
One of those two things will fix it.
Sounds like your distributor is off a tooth. Try repositioning one tooth over. Afterwards you need to bump the starter to make it seat into the pump.
If you are running an aftermarket cam? You may need to re-index your distributor gear 180 degrees. That would be dimple 180 degrees opposite of rotor tip. My old comp cam was that way.
One of those two things will fix it.
Team Owner
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From: Washington Michigan
Thread Starter
Instructor
Joined: Mar 2011
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From: Schererville IN
Ah - of course. So i'm just a couple of degrees off at 19 vs. 16.
Re: rotating, I have the original cam in there. Last fall a mechanic told me the distributor was 1 tooth off and said he fixed that. Wonder if he didn't, or did and shouldn't have. Am i better off rotating 180 or moving 1 tooth?
Re: rotating, I have the original cam in there. Last fall a mechanic told me the distributor was 1 tooth off and said he fixed that. Wonder if he didn't, or did and shouldn't have. Am i better off rotating 180 or moving 1 tooth?
Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
Ah - of course. So i'm just a couple of degrees off at 19 vs. 16.
Re: rotating, I have the original cam in there. Last fall a mechanic told me the distributor was 1 tooth off and said he fixed that. Wonder if he didn't, or did and shouldn't have. Am i better off rotating 180 or moving 1 tooth?
Re: rotating, I have the original cam in there. Last fall a mechanic told me the distributor was 1 tooth off and said he fixed that. Wonder if he didn't, or did and shouldn't have. Am i better off rotating 180 or moving 1 tooth?
Make sure your cap is wired correctly before you change anything. Sorry, I don't have a picture.
Team Owner
Joined: Oct 2000
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From: Washington Michigan
Ah - of course. So i'm just a couple of degrees off at 19 vs. 16.
Re: rotating, I have the original cam in there. Last fall a mechanic told me the distributor was 1 tooth off and said he fixed that. Wonder if he didn't, or did and shouldn't have. Am i better off rotating 180 or moving 1 tooth?
Re: rotating, I have the original cam in there. Last fall a mechanic told me the distributor was 1 tooth off and said he fixed that. Wonder if he didn't, or did and shouldn't have. Am i better off rotating 180 or moving 1 tooth?
Thread Starter
Instructor
Joined: Mar 2011
Posts: 248
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From: Schererville IN
Cap is wired correctly - I now say 18436572 in my sleep. John - mathematically i understand what you're saying, but if it's the original cam should it need to be rotated? Or even moved one tooth for that matter? Maybe someone made one of those "corrections" in the past without understanding things fully and now i am just getting back to original specs.
Le Mans Master
Joined: Aug 2009
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From: Houston Texas
St. Jude Donor '10-'12-'13
Original cam may have nothing to do with it.
I assumed that. When I installed my current GM cam. I had to put mine back 180 degrees to the dimple even with rotor tip.
I assumed that. When I installed my current GM cam. I had to put mine back 180 degrees to the dimple even with rotor tip.
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Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
Cap is wired correctly - I now say 18436572 in my sleep. John - mathematically i understand what you're saying, but if it's the original cam should it need to be rotated? Or even moved one tooth for that matter? Maybe someone made one of those "corrections" in the past without understanding things fully and now i am just getting back to original specs.
You indicated your firing order is correct. Are the plug wires in the appropriate terminals as displayed in the picture? If they are, proceed with moving a tooth and/or turning the gear.
Thread Starter
Instructor
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From: Schererville IN
Getting frustrated and confused. Rotated distributor 1 tooth clockwise. Now i'm having timing trouble in the opposite direction. Went from initial of 9.5* to over 30*, and vac is hitting starter solenoid. Can't get total anywhere near 36*. Sounds smoother than before i rotated, but that timing is no good. I don't see how rotating 180* is good, or even possible - that will put my vac and tach 180* from where they are - which is neither correct nor possible with the tach cable. Right? Note: when i rotated distributor 1 tooth, it fully seated - didn't need to bump starter to get seated. I feel like i'm missing something basic - i'm no mechanic and no veteran with this car, so maybe though basic it's beyond me. Is there something i haven't looked at that would affect timing so much?
Le Mans Master
Joined: Aug 2009
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From: Houston Texas
St. Jude Donor '10-'12-'13
Sounds like you didn't actually move it one tooth. It seems like it settled back into it's old spot. If you moved it a tooth? You would have to make it settle as described above.
Ok so one tooth didnt help. Go back and start over.
Find TDC and index your distributor gear 180 degrees from it's present position. You have to knock the roll pin out to do it. Then re-install with rotor at the #1 cyl on the cap.
If that makes it worse? The reverse it again and start over. You may have to play with the toot position again. Keep at it till you get it right.
Ok so one tooth didnt help. Go back and start over.
Find TDC and index your distributor gear 180 degrees from it's present position. You have to knock the roll pin out to do it. Then re-install with rotor at the #1 cyl on the cap.
If that makes it worse? The reverse it again and start over. You may have to play with the toot position again. Keep at it till you get it right.
Last edited by MiguelsC2; Apr 30, 2011 at 09:04 PM.
Le Mans Master
Joined: Aug 2009
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From: Houston Texas
St. Jude Donor '10-'12-'13
Ps. Keep it simple. Start from square one with no changes to the gear. So you have a baseline. Then try the various recommendations here. Be sure not to forget your place each time.
Melting Slicks
Joined: May 2007
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From: cooper city florida
I went through the same thing your going through. Easy fix.....pull the distributor out......on the bottom of the shaft is the drive gear that's held in place by a pin. Take a punch and drive out the pin. Remove gear from shaft and rotate it 180 degrees and reinstall gear and pin. You have now picked up a half a tooth, and your vacuum can will sit between the intake runner, and the coil bracket. Now make sure your #1 piston is at top dead center on the compression stroke, and drop the distributor in and make sure that the rotor is pointing to the #1 plug wire on the cap.
Drifting
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From: Putnam Valley, New York. Amateur Radio Operator K2NS
180*
RON
Last edited by rongold; May 1, 2011 at 11:56 AM.
Thread Starter
Instructor
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From: Schererville IN
Thank you all for the info - making more sense now. With all the comments i've seen on different posts re: rotating 180* I didn't think there could be that many people driving around with the vac and tach on the wrong side.
So since i moved 1 tooth, sounds like i should go back to where i was, mark where rotor is pointing, pull distributor and rotate gear 180*, then put distributor back in, and rotor will be pointing approx 14* clockwise from the mark, then find TDC. Is that right? or should i find TDC first?
So one other question - i've been searching on exactly how to find TDC, and seen different suggestions and levels of complexities. I'm not clear how to find TDC, or what i do once i find it. Are there any posts anyone could point me to that already explains it, or can it be explained here? Your help and advice is greatly appreciated.
So since i moved 1 tooth, sounds like i should go back to where i was, mark where rotor is pointing, pull distributor and rotate gear 180*, then put distributor back in, and rotor will be pointing approx 14* clockwise from the mark, then find TDC. Is that right? or should i find TDC first?
So one other question - i've been searching on exactly how to find TDC, and seen different suggestions and levels of complexities. I'm not clear how to find TDC, or what i do once i find it. Are there any posts anyone could point me to that already explains it, or can it be explained here? Your help and advice is greatly appreciated.
Team Owner
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From: Washington Michigan
So one other question - i've been searching on exactly how to find TDC, and seen different suggestions and levels of complexities. I'm not clear how to find TDC, or what i do once i find it. Are there any posts anyone could point me to that already explains it, or can it be explained here? Your help and advice is greatly appreciated.
Once you get to #1 TDC on the compression stroke, back it up a bit so the timing index line on the balancer aligns with the 10* advanced mark on the timing tab, and install the distributor with the rotor pointing to the #1 wire tower. Then fire it up and touch up the timing setting with your timing light (vacuum advance disconnected and plugged).
Thread Starter
Instructor
Joined: Mar 2011
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From: Schererville IN
Should I do this before removing gear and rotating 180*, or assume I will need to rotate gear 180*, so do that and then find TDC? I mean, is it possible i'm not at TDC now, but once i am, the timing will be able to be set correctly without rotating gear?
Le Mans Master
Joined: Aug 2009
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From: Houston Texas
St. Jude Donor '10-'12-'13
Yes, find the correct TDC before doing anything. Or you will never have an accurate baseline.
Le Mans Master
Joined: Aug 2009
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From: Houston Texas
St. Jude Donor '10-'12-'13
0 is how I do mine.
Melting Slicks
Joined: Oct 2002
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From: St Louis MO
If you don't have a helper or a remote
starter button, you can do it this way: If you bump it over until the
index line on the balancer aligns with the "0" mark on the timing
tab, it's either on #6 TDC on the compression stroke or on #1 TDC on the compression stroke. Pop the driver's side valve cover and look at the valves for #1; if they're closed (rocker arms parallel like photo below), you're on #1 TDC on the compression stroke. If they're not, you're on #6 TDC on the compression stroke, and need to bump it over one more revolution.
starter button, you can do it this way: If you bump it over until the
index line on the balancer aligns with the "0" mark on the timing
tab, it's either on #6 TDC on the compression stroke or on #1 TDC on the compression stroke. Pop the driver's side valve cover and look at the valves for #1; if they're closed (rocker arms parallel like photo below), you're on #1 TDC on the compression stroke. If they're not, you're on #6 TDC on the compression stroke, and need to bump it over one more revolution.
It is far easier to look at the #3 intake valve (3rd valve spring from the left) - if it is open (very easy to see because it is open a lot), you are at TDC-firing. If #3 intake valve is closed, you're at TDC-overlap.