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Can't seem to find the timing mark [message #262239] Thu, 18 September 2014 13:13 Go to next message
An87ttype is currently offline  An87ttype   United States
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Registered: September 2012
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I'm working through my carb rebuild and went to check the timing. The mark is clean on the crank so I should be able to see it. I've tried to see it with the advance on and off, revving it to see if it comes into view. On the number 1 plug according to the MM. I do think it's retarded by the way it runs, but not that much. It's pretty hard to get a good view of the whole crank but it does not look like its anywhere on the top half. Any idea of what I could be missing? Seems pretty strange...Thanks

1975 Eleganza II Hudson Valley NY
Re: Can't seem to find the timing mark [message #262240 is a reply to message #262239] Thu, 18 September 2014 13:27 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
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Sir it can be very tricky to get the right angle of your eye ball to see it. I use a timing light with a degree dial on it. I dial in the degree I want and set it on tdc cause it is in sight better. But your balancer might have moved. Remove #1 plug finger over hole and bump over to close to tdc on compression, use a socket and ratchet to bring right on tdc, a pencil with eraser end in the hole is a usable indicator and look and see if tdc is 0 on timing mark. If not you will have to replace balancer. I was told by a feller that builds engines that bout 1/3 he finds is bad.



An87ttype wrote on Thu, 18 September 2014 14:13
I'm working through my carb rebuild and went to check the timing. The mark is clean on the crank so I should be able to see it. I've tried to see it with the advance on and off, revving it to see if it comes into view. On the number 1 plug according to the MM. I do think it's retarded by the way it runs, but not that much. It's pretty hard to get a good view of the whole crank but it does not look like its anywhere on the top half. Any idea of what I could be missing? Seems pretty strange...Thanks



C. Boyd
76 Crestmont
East Tennessee
Re: Can't seem to find the timing mark [message #262241 is a reply to message #262239] Thu, 18 September 2014 13:30 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
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An87ttype wrote on Thu, 18 September 2014 13:13
I'm working through my carb rebuild and went to check the timing. The mark is clean on the crank so I should be able to see it. I've tried to see it with the advance on and off, revving it to see if it comes into view. On the number 1 plug according to the MM. I do think it's retarded by the way it runs, but not that much. It's pretty hard to get a good view of the whole crank but it does not look like its anywhere on the top half. Any idea of what I could be missing? Seems pretty strange...Thanks


It's really hard to see, get some white nail polish or whiteout and paint the line on the dampner. I paint a wide stripe across it then the grove int he pully shows up petty nice.
Yuo can also put some dots before and after to make it easier to find.


Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: Can't seem to find the timing mark [message #262242 is a reply to message #262239] Thu, 18 September 2014 13:30 Go to previous messageGo to next message
Chris Tyler is currently offline  Chris Tyler   United States
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Registered: September 2013
Location: Odessa FL
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Have you tried using some paint or white out to make the mark stand out?
You can make a piston stop out of a spark plug no- fouler adapter that will tell you top dead center. Rotate the engine by hand until it hits, thin back off slowly on the stop until it doesnt stop the rotation
You caqn get a timing tape for the balancer to check your advance curve, but they never last long. Im a big fan of dial back to zero timing lights.


76 Glenbrook
Re: [GMCnet] Can't seem to find the timing mark [message #262244 is a reply to message #262240] Thu, 18 September 2014 13:39 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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Senior Member
On Thursday, September 18, 2014, Charles Boyd
wrote:

> Sir it can be very tricky to get the right angle of your eye ball to see
> it. I use a timing light with a degree dial on it. I dial in the degree I
> want and set it on tdc cause it is in sight better. But your balancer
> might have moved. Remove #1 plug finger over hole and bump over to close to


Looks like this
http://www.gmcmhphotos.com/photos/misc/p30454-timing455.html

Erf


> tdc on compression, use a socket and ratchet to bring right on tdc, a
> pencil with eraser end in the hole is a usable indicator and look and see
> if tdc
> is 0 on timing mark. If not you will have to replace balancer. I was
> told by a feller that builds engines that bout 1/3 he finds is bad.
>
>
>
> An87ttype wrote on Thu, 18 September 2014 14:13
>> I'm working through my carb rebuild and went to check the timing. The
> mark is clean on the crank so I should be able to see it. I've tried to see
>> it with the advance on and off, revving it to see if it comes into view.
> On the number 1 plug according to the MM. I do think it's retarded by the
>> way it runs, but not that much. It's pretty hard to get a good view of
> the whole crank but it does not look like its anywhere on the top half. Any
>> idea of what I could be missing? Seems pretty strange...Thanks
>
>
> --
> C. Boyd
> 76 Crestmont
> East Tennessee
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>


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Re: Can't seem to find the timing mark [message #262250 is a reply to message #262239] Thu, 18 September 2014 14:57 Go to previous messageGo to next message
larry.whisler is currently offline  larry.whisler   United States
Messages: 356
Registered: August 2005
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Senior Member
Are you using the plug wire that goes to the number 1 cylinder which
is the front plug on the driver's side of the engine?

I had the same problem a while ago and figured out that I had the
light hooked up to number 3.

larry
Re: Can't seem to find the timing mark [message #262254 is a reply to message #262250] Thu, 18 September 2014 15:43 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
Get under the coach and have some one tap the starter until ypu see the timing groove come around on the bottom. Got to Walmart and get a small bottle of white out Yes they still sell that stuff. Paint the groove in the harmonic balancer with white out. Now go back up top and connect your timing light. Start the engine and see what you can find. If you do not see the white mark and the engine is running fine it is time to start looking for a slipped vibration dampener.

Here are pictures of Roger Black's slipped harmonic balancer and a new one showing the indexing marks: Go forward and back a few photos to see more pictures of the balancers.

http://www.gmcmhphotos.com/photos/harmonic-balancer-notes/p5570.html





Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Can't seem to find the timing mark [message #262294 is a reply to message #262239] Thu, 18 September 2014 22:46 Go to previous message
An87ttype is currently offline  An87ttype   United States
Messages: 157
Registered: September 2012
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Senior Member
Found it! I when out and looked again now that it's dark. My old timing lights a little dim so it works better at night. Now that I think of it , it might be from the 70's too!

Your right about not being able to see the index. I can't tell if it's at 10 or 12 btc at 600rpm. Seems about right though. I don't see any way to set it accurately without a dial-able timing light. No way to get a direct line of site on it.

Thanks all...


1975 Eleganza II Hudson Valley NY
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