New carb, timing mark issue

[mainermikeyd]

During my install of my new edelbrock 1406 carb this morning, on my 350(Hecho Cinco GM) I wanted to start from scratch an make sure to get everything installed correctly for best performance!!!! I got TDC, marked my balancer, pulled an plugged vacuum advance went to set timing, an found out that my timing mark on balancer is nowhere near the timing tab, advanced or retarded!!!! Anybody had similar problems or suggestions???

[Rollie396]

As a starting point,how did you find tdc?

[mainermikeyd]

yes got TDC on the #1 piston, drivers side first cylinder front of truck

[us111]

hello,are you sure you have tdc on correct stroke? (exhaust).when it comes
up on correct stroke you will have air blow out of the plug hole.that will be
your correct tdc.lots of ways of doing it,i just roll up piece of tp,jam it in plug hole,when motor rotates over to correct stroke paper will blow out.not perfect but close.thats the very first thing to make sure of.

[LONGHAIR]

Originally Posted by us111

hello,are you sure you have tdc on correct stroke? (exhaust).when it comes
up on correct stroke you will have air blow out of the plug hole.that will be
your correct tdc.lots of ways of doing it,i just roll up piece of tp,jam it in plug hole,when motor rotates over to correct stroke paper will blow out.not perfect but close.thats the very first thing to make sure of.

If the timing mark has "moved" because of the rubber ring, that method will not tell you anything....and could also be the reason that the mark doesn't show with the timing light.

You really need to verify TDC with a piston stop. This will give you an exact place to start. Also verify that you have the correct timing tab and matching balancer

[73chevyman]

i never had this problem but it sounds to me you did the TDC on the wrong stroke. all you have to do is crank the motor till your thumb is pushed out the number 1 spark plug hole reset your distributor and wahlah start her up set your timing either 8 degrees above manual or 12 degrees above auto. put a vacuum tester in line and fine tune your carb you should have a steady reading between 15 and 22 your in the good anything lower not good anything above not good and you should be good to go. I just rebuilt my 350 due to a wipped cam just did my fine tunning today and I had 20 on the vacuum gauge it was not so steady in the beginning but got it perfect. it held around 20 no movement what so ever. my carb is a 1407 so your not to far off from me. now if your not so stock like i am none of this will apply need to get all your timing settings for your set up hope this helps. jack

[piecesparts]

Where are you looking at for your timing mark? On the later GM motors the timing is set by looking down behind the water pump, from the top of the engine. Just a question and possibly an observation of a missed opportunity.

To Be SURE, pull the number one plug, turn the engine over by hand and feel for the outrush of air from the cylinder (thumb over the plug hole) and then work with the piston until it is at the top of the stroke. Now look for the mark on your balancer and see where it truly is. That is probably where the tab should be. However, it is possible that your balancer is bad, but let's not hope for that one.

[mainermikeyd]

The timing tab is located drivers side, mark on my balancer is at about 12 oclock timing tab at about 3. Wondering if I opened up a can of worms, I have driven it all winter an most of this spring, had to replace the carb cuz the base was cracked from PO tightening down the 2 drivers bolts too tight!!!!

[piecesparts]

Originally Posted by mainermikeyd

The timing tab is located drivers side, mark on my balancer is at about 12 oclock timing tab at about 3. Wondering if I opened up a can of worms, I have driven it all winter an most of this spring, had to replace the carb cuz the base was cracked from PO tightening down the 2 drivers bolts too tight!!!!

It sounds like a balancer for a mid eighties truck engine with a timing tab for a pre 79 engine. One of the two would need to be changed to get it right.

The 80s models timing tab would be at 12 O clock, just behind the water pump and the earlier timing tab would be at about 3 O clock.

[LONGHAIR]

Originally Posted by piecesparts

It sounds like a balancer for a mid eighties truck engine with a timing tab for a pre 79 engine. One of the two would need to be changed to get it right.

The 80s models timing tab would be at 12 O clock, just behind the water pump and the earlier timing tab would be at about 3 O clock.

This was my point about "matching" balancer...but it is not absloutely necessary. If you verify the TDC with a piston stop, you can mark the balancer to match it. Then your timing light will work correctly.

[mainermikeyd]

This is why this forum is such a useful tool. longhair & piecesparts, I believe you were both correct!!! Frame an chassis is from a 79 or older truck, cab is from a 82, so when the PO had a new motor installed they musta installed all the previous front end parts on the motor, including the timing cover!!!!! THANKS at least now I have some direction to go in

[piecesparts]

Originally Posted by mainermikeyd

This is why this forum is such a useful tool. longhair & piecesparts, I believe you were both correct!!! Frame an chassis is from a 79 or older truck, cab is from a 82, so when the PO had a new motor installed they musta installed all the previous front end parts on the motor, including the timing cover!!!!! THANKS at least now I have some direction to go in

Go for it....