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.
ok, so I unwrapped my shiny new TDC check tool, & headed out to the garage to see what it tells me.
Here's what I did:
1) threaded the toolinto cyl#1(drivs side fwd)
2) rotated the engine until it stopped on the tool
3) made a mark on the balancer at the "0" mark on my newly installed timing tab
4) rotated the opposite direction until it stopped
5) made another mark at the same place
6) made a mark between those two marks: I believe that should be TDC
Some notes of interest:
1) The factory timing mark on the HB is at 12:00
2) The distrib rotor is pointing at the REAR of the car..
So, I can conclude that either
1) I've got a replacement engine with a timing mark somewhere at 12:00(haven't looked yet)..and the distro was way outta whack...
2) the HB has slipped
Are you on the compression stroke or exhaust stroke?
crap... I forgot it could be the exhaust...
I'm not wanting to yank the valve cover to look at vales, only because it's a pita with the tall covers....
I'll revisit this...
and thank you for that most elementary of reminders..
I'm not wanting to yank the valve cover to look at vales, only because it's a pita with the tall covers....
I'll revisit this...
and thank you for that most elementary of reminders..
Were your distributor is pointing doesn't matter as long as you moved the wires to match. Just be aware which ever terminal it's pointing at is #1, then place the rest in order off that.
yeah, I shoulda known better…
back at it tomorrow!
It doesn't really matter which stroke you're on as Top Dead Center on #1 occurs at the same place whether it's compression/power or exhaust/intake with the balancer mark and timing tab. In your test, is the mid-point between rotation stops at the engraved balancer mark? This was the point of doing the stop-to-stop test, to determine if the outer ring had slipped. If it has, then the engraved mark will not be centered.
Last edited by barkingrats; Sep 12, 2023 at 10:50 PM.
It doesn't really matter which stroke you're on as Top Dead Center on #1 occurs at the same place whether it's compression/power or exhaust/intake with the balancer mark and timing tab. In your test, is the mid-point between rotation stops at the engraved balancer mark? This was the point of doing the stop-to-stop test, to determine if the outer ring had slipped. If it has, then the engraved mark will not be centered.
I guess the new priority is going to be searching to see if there is another timing tab on the engine, as some have suggested COULD be the case if the engine isn't original..
If there ISN'T another timing tab, then I've got bigger problems.
Either way, here's the good news: I found a fellow who lives a couple of minutes away, and he has a long history of chevy racing engines/building
He came over a couple nights ago, & did a overview of the thing, & gave me some things to do before he comes back again.(put in new points/condenser etc)
I'll run all of this by him... I'm sure he'll get me sorted out.
From: At my Bar drinking and wrenching in Lafayette Colorado
So you used your TDC tool, rotated the engine one way until it stopped... made a mark on the balancer at the "0" line on the timing tab.... rotated the engine the other way until it stopped... made a mark at the "0" line on the timing tab.... and then made a new timing line halfway between the two lines. This new line did not line up with the existing line on the balancer. When you align your new line with the "0" line on the timing tab, your original line on the balancer points straight up at the 12:00 position.
Is that an accurate recap of what you did? If so, you have accurately determined and set the engine to the TDC position. It may be 180 degrees out on the firing stroke versus exhaust stroke, but that's irrelevant to the TDC position.
If so, you have a defective balancer. Once you get those first two lines established, the timing line should be located exactly between the two lines. There is no small block Chevy that uses a timing tab at the 12:00 position, nor any SBC balancer that has its timing line at the 12:00 position when the engine is at TDC. New points & condenser aren't going to change that fact. Fix the obvious problem: replace the balancer, and then re-do the TDC check to verify the accuracy of your timing tab and make any minor correction necessary.
Lars
So you used your TDC tool, rotated the engine one way until it stopped... made a mark on the balancer at the "0" line on the timing tab.... rotated the engine the other way until it stopped... made a mark at the "0" line on the timing tab.... and then made a new timing line halfway between the two lines. This new line did not line up with the existing line on the balancer. When you align your new line with the "0" line on the timing tab, your original line on the balancer points straight up at the 12:00 position.
Is that an accurate recap of what you did? If so, you have accurately determined and set the engine to the TDC position. It may be 180 degrees out on the firing stroke versus exhaust stroke, but that's irrelevant to the TDC position.
If so, you have a defective balancer. Once you get those first two lines established, the timing line should be located exactly between the two lines. There is no small block Chevy that uses a timing tab at the 12:00 position, nor any SBC balancer that has its timing line at the 12:00 position when the engine is at TDC. New points & condenser aren't going to change that fact. Fix the obvious problem: replace the balancer, and then re-do the TDC check to verify the accuracy of your timing tab and make any minor correction necessary.
Lars
Yes Lars, what you wrote out, is exactly what I did.
And no worries, I totally get that points & cond won;t fix this issue.
I'll get with my local guy & nail down this TDC/mark issue before I do ANYTHING else!
Thanks for chiming in!
Rich
ps. I wonder if a nice cold Guinness might not help here...
;O
Yes Lars, what you wrote out, is exactly what I did.
And no worries, I totally get that points & cond won;t fix this issue.
I'll get with my local guy & nail down this TDC/mark issue before I do ANYTHING else!
Thanks for chiming in!
Rich
ps. I wonder if a nice cold Guinness might not help here...
;O
You already nailed down the balancer mark.......now replace it. Your local guy or Guiness isn't going to do anything....nobody is going to be able to do more than you have already done. About half of these cars have a spun balancer on them.....this is no mystery
Yes Lars, what you wrote out, is exactly what I did.
And no worries, I totally get that points & cond won;t fix this issue.
I'll get with my local guy & nail down this TDC/mark issue before I do ANYTHING else!
Thanks for chiming in!
Rich
ps. I wonder if a nice cold Guinness might not help here...
;O
Just went through this fun this week on a widow neighbors '59 Pickup her husband built for her. Timing mark was 6" from where it should be. I kept looking for the timing mark with timing light..and even tried another one in case it was barfed. Then I finally noticed the mark a LONG way from where it should be.
My piston stop is a gutted spark plug where I tapped it internally and inserted a long bolt. Works great for the last 20-30 years!
Just went through this fun this week on a widow neighbors '59 Pickup her husband built for her. Timing mark was 6" from where it should be. I kept looking for the timing mark with timing light..and even tried another one in case it was barfed. Then I finally noticed the mark a LONG way from where it should be.
My piston stop is a gutted spark plug where I tapped it internally and inserted a long bolt. Works great for the last 20-30 years!
From: At my Bar drinking and wrenching in Lafayette Colorado
Originally Posted by 427Hotrod
And there were some timing tabs at 12'o'clock as I recall from my dealership days.JIM
Okay, wiseguy Jim... one year only in '86... I think we have solidly established that his balancer has slipped and that the mark should not be at the 12:00 position on his '74... I might have to lower your Texas flag below the level of my Colorado flag, and move the Shiner Bock tap handle from the right side to the left side of the tap tower for that one.... So can we say that "no stock C3 Vettes ever had the timing tab at the 12:00 position."
Lars
They do not even have to be all that old.
I just had the balancer almost slip off on my wife's 2007 Honda.
"That's what all that noise was"
It came off in 2 pieces.
Okay, wiseguy Jim... one year only in '86... I think we have solidly established that his balancer has slipped and that the mark should not be at the 12:00 position on his '74... I might have to lower your Texas flag below the level of my Colorado flag, and move the Shiner Bock tap handle from the right side to the left side of the tap tower for that one.... So can we say that "no stock C3 Vettes ever had the timing tab at the 12:00 position."
Lars
LOL....the only reason it stood out to me was I was just doing it last week on that truck and i was thinking I seemed to remember some being behind the water pump...and the ones with the timing probe hole. Not knowing what cobbled up mess of an engine might be in it...other than they said it was a 350 and it had OEM heads....I figured it might have wrong balancer on it. She has a short water pump so no way to see a tab back in there anyway. But her mark was way down below to the bottom..so it wouldn't be one of these funky ones anyway that would have been on the other side of the timing pointer if it was. She needs a balancer too!
That's alright...I'll keep your CO flag at full mast in the Batcave/Skunkworks shop!!
