• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Timing gear question

Richard Cranium

FBBO Gold Member
FBBO Gold Member
Local time
8:31 PM
Joined
Feb 20, 2012
Messages
69,236
Reaction score
258,827
Location
New Hampster
I installed a new cam, timing gears & chain in the 440 last evening. The crank gear has 3 keyway slots & I lined up the "0" with the punch mark on the cam gear. No problem there. Put the timing cover on but when I put the balancer on on, the timing mark was a couple inches off from the TDC mark on the cover. It's been a while since I did a cam job and I just want to check with the experts here to see if this sounds right or not.

Below is a picture of the old gear with the 0 mark that I lined up with the cam dot....

DSCF9229.JPG
 
You might be looking at the balancer, that the outer ring has slipped. Just ballpark, but from the keyway groove, to 0 mark TDC, should be right at 90 degrees.

Best on timing the cam, to use a dial indicator/degree wheel, and check things off top of piston.
 
I installed a new cam, timing gears & chain in the 440 last evening. The crank gear has 3 keyway slots & I lined up the "0" with the punch mark on the cam gear. No problem there. Put the timing cover on but when I put the balancer on on, the timing mark was a couple inches off from the TDC mark on the cover. It's been a while since I did a cam job and I just want to check with the experts here to see if this sounds right or not.

Below is a picture of the old gear with the 0 mark that I lined up with the cam dot....

View attachment 413021

All engine timing is off top dead center of the number 1 piston. If you are at TDC the keyway for the crank gear should point straight up. When the gear is put on, if a dot exists, it should be straight up. If it's a multi keyed gear there will be a number above the slot to indicate how much advance/retard that position will render when used. When the cam is in the right position in reference to the crank, #1 intake and exhaust should be closed and the lifters on the base circle of the cam lobes for those particular valves. Then, and only then, can the chain and sprockets be installed. Slots in either gears allow for slight advance or retarding of the timing between the crank and cam and I would suspect that either a gear is put on backwards or the timing marks are not at 0 position. This would be because you've used a key slot in the gear that is for more advance or retarding of cam position. You must leave the crank at TDC and not move it when you apply the timing chain. Only the cam is to be moved. Examine your gears closely for their markings and positions and redo the operation again. If it's not right you'll run out of distributor adjustment, be subject to farts out the carb and generally have a poor running engine, if it fires at all. Use your original gear to verify the tooth position on the new gear for TDC
 
the timing gears have nothing to do with his question, question was why the timing mark on the damper didn't line up with the timing cover, either the timing cover tab is off or the damper is slipped or defective if the no. one piston it truly at top dead center.
 
I thought of the slipped balancer, but this engine already does have a new balancer. I was looking at a video on line (below) & the crank keyway on that video was positioned at 1:00 to get the two gear marks to line up, but crank key on mine was positioned at 11:00. I think I've got to pull the balancer & cover off to take a look at things again.


 
All engine timing is off top dead center of the number 1 piston. If you are at TDC the keyway for the crank gear should point straight up. When the gear is put on, if a dot exists, it should be straight up. If it's a multi keyed gear there will be a number above the slot to indicate how much advance/retard that position will render when used. When the cam is in the right position in reference to the crank, #1 intake and exhaust should be closed and the lifters on the base circle of the cam lobes for those particular valves. Then, and only then, can the chain and sprockets be installed. Slots in either gears allow for slight advance or retarding of the timing between the crank and cam and I would suspect that either a gear is put on backwards or the timing marks are not at 0 position. This would be because you've used a key slot in the gear that is for more advance or retarding of cam position. You must leave the crank at TDC and not move it when you apply the timing chain. Only the cam is to be moved. Examine your gears closely for their markings and positions and redo the operation again. If it's not right you'll run out of distributor adjustment, be subject to farts out the carb and generally have a poor running engine, if it fires at all. Use your original gear to verify the tooth position on the new gear for TDC
At TDC the key for the crank is at 2 o'clock.
Mine don't line up either. After market balancer. If you used a degree wheel and are confident of TDC, put a mark on the balancer and use it.
 
I now see where I went wrong; somehow I got the crank got rotated into the wrong position. My crank key is in the 11 o'clock keyway slot, not the 1:00 o'clock keyway. Silly me. :realcrazy:

39-640x480.jpg
 
At TDC the key for the crank is at 2 o'clock.
Mine don't line up either. After market balancer. If you used a degree wheel and are confident of TDC, put a mark on the balancer and use it.

Ain't nothing like doing everything right only to have that high dollar degreed balancer off by 4 degrees on the timing cover tab. Mine is the same way so I need to install a new tab so its correct.

Don't forget to rotate it over another turn to get tdc on #1. With the dots together it is tdc on #6, with both dots at 12 oclock on their sprockets you get tdc on #1.
 
and pre oil chain so you have less wear on start up
 
In a nutshell...pretty simple. Balancer goes on the crank, only one way, either right, or wrong. #1 piston at TDC, then balancer on the crank, the timing mark on the balancer should be exactly at 0 (TDC) on the chain cover timing tab.
Crank don't care where the cam is, only connected by the chain.
 
A lot of after market balancers are incorrect. It sounds like your assuming that the tab on the cover is in the correct position or the degree marks on the balancer are correct. If this it what you are relying on, you may find that your piston is no longer at TDC but down in the hole.
DEGREE IT
 
Last edited:
Stated it in the last post. The timing marks on after market balancers are not all correct. One would assume that 0 on a balancer should line up with the hole in the timing tab but not all do.
When you degree it you can make your own mark on the balancer for TDC and then line that up with the hole in the tab.
Why would the crank not care where the cam is? They are both relative to timing.
 
Stated it in the last post. The timing marks on after market balancers are not all correct. One would assume that 0 on a balancer should line up with the hole in the timing tab but not all do.
When you degree it you can make your own mark on the balancer for TDC and then line that up with the hole in the tab.
Why would the crank not care where the cam is? They are both relative to timing.
It would seem to make more sense to mod the timing tab to line up with the balancer 0 tdc otherwise the 90* hash marks and the marked degrees on the balancer would be useless.
 
You could but then you have to take it apart. Seemed easier to use a felt tip marker and/or timing tape.
 
I welded a new tab to the cover, I have had tape fly off before lol.
20170414_171900.jpg
 
Auto Transport Service
Back
Top