Jump to content

IGNORED

Timing hole #2


siteunseen

Recommended Posts

Does this look about right for number two with a new chain?  All my other indicators are showing top center and I'm thinking if it's advanced it should be ahead of the thrust plate line.  The dowel notch is to the right side of the line half way.  Please let me know if I'm wrong, it happens often.

 

post-23570-0-23533800-1449011374_thumb.j

 

Thanks,

Cliff

Link to comment
Share on other sites

Why are you using number two with a new chain? Number 1 is the standard position for a new chain. Positions 2 and 3 are to accommodate chain stretching as it ages and wears.

With the crank at zero degrees and the bright link on the marked lug of it sprocket, the second bright link should line up at about 2 o'clock on the cam sprocket. Align the number 1 cog at about 2 o'clock engaging the second bright link. Mount the cam sprocket on the cam and the number 1 hole should be at 12 o'clock.

As the chain stretches, valve timing retards. Positions 2 and 3 advance the valve timing 4 and 8 degrees respectively to accommodate for the stretching. When the valve timing is late while at position 3, it is time to replace the chain.

  • Like 1
Link to comment
Share on other sites

I don't have access to the Honsowetz or Bob Waar "How to Modify..." books for tech support at the moment but this is accepted practice to gain a little more low-end grunt at the expense of high-end power. To be safe, cycle the cam by hand first to make sure everything is as it appears and there's no unexpected resistance.

  • Like 1
Link to comment
Share on other sites

It looks like "after adjustment" in the FSM.  So #1 should look like "before adjustment".  Implying that your #2 hole is as good as you can get between hole #1 and #2 choices.

 

Are you sure that the tight side of the chain is tight?  I always have a tendency to over-rotate the engine while watching the damper pulley mark.  Then if I rotate the engine backward, I have to turn the timing chain sprocket backward also, independently, to get the chain's tight side tight again.

  • Like 1
Link to comment
Share on other sites

Thank you all.  Madkaw, that makes it too easy!  :o

 

DJWarner I had to run my distributor all the way clockwise before the rebuild so I'm hoping #2 will give me some adjustment there.  If not I'll go to #3.  When I rebuilt my 2.8 I set it up on #3 from the beginning and have been very happy with how it runs.  I won't drive them enough to stretch the chain.  Honsowetz says it in his book like NVZEE posted and I noticed on this build Tom Monroe uses #2 on the L20 he builds in his book.

 

Zed Head, yes the tight side is tight, I learned that the hard way when I was trying to time the oil pump last year.  Always go clockwise with the crank bolt and never back up, make another rotation instead.  I really need to use the FSM more, I wish I knew it as well as you do.  :)

Link to comment
Share on other sites

Cliff,

it is that easy if you take the proper precautions . Once you have the engine properly set up as far as #1 on the initial install(bright link stuff), it's just a matter of changing settings on the cam sprocket later on if you want. You could set up #1 right now and after running the motor for a while or after break in , just move up to #3 and see if the butt dyno feels any different.  

But what about getting the shiny links in the right spot? NOT necessary.  

 

 

Procedure:

Get #1 cylinder to TDC COMPRESSION STROKE. I usually take #1 spark plug out and stick a vacuum plug in there or something that will pop out when the piston comes up on compression.

It doesn't have to be exact, but you should see the #1 mark somewhere around the 2 o'clock position. WAIT, no shiny link? IT DOES NOT MATTER, as long as your are TDC compression stroke.

Now take a rag and clean off the chain link that is corresponding to  #1 mark and then color it in with a permanent marker.

DON"T FORGET TO USE YOUR CHAIN TENSIONER TOOL NOW!

Now take out the cam sprocket bolt and spin the sprocket around until the number you want corresponds with the marked link.

You will probably have to turn the cam a bit to get the sprocket to drop in place. This is probably the most frustrating part of the process and can be the most stressfull. Don't be afraid, just a slight turn either way should allow the dowel to line up. I'm thinking maybe a quarter inch of movement will get it. Don't panic if it take several tries. It takes a little bit of effort to pull up the sprocket and slide it into the exact spot. 

Now get the bolt back in the sprocket.

DON"T FORGET THE TENSIONER TOOL!!

Link to comment
Share on other sites

Anytime that sprocket gets removed , the tensioner tool should be in place-if that's what you are asking.

 

 

This is based on the presumption that later adjustments the oil pan will be on and you want to make sure the chain stays put on the crank

Edited by madkaw
Link to comment
Share on other sites

I think I'm being too paranoid that my instructions are not clear enough ,and or misleading , so I missed the humor - thanks.

Also trying to relax the idea that it is voodoo to change valve timing, but you do need to do it right.

  • Like 1
Link to comment
Share on other sites

Hi Cliff,

 

Now you have me confused. How do you think changing valve timing will change the distributor timing setting? They both run off the crankshaft but have different take-offs and are independently set-able.

 

What was your timing goal and how did you measure it. I know the FSM specifies 5 degrees BTDC, but this is done with a light directly attached to the points and has no centrifugal advance as the engine is not running using this technique. If I am reading the drawing in the Haynes manual correctly, rotating the distributor clockwise advances the timing.

 

If you are looking to set the distributor less clockwise, you would be retarding the timing while you are advancing the valve timing. Is this your goal?

 

Of course the one point we never asked, is this a new chain?

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

By using this site, you agree to our Privacy Policy and Guidelines. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.