Jump to content
eaker02

74tii- which way to turn screw for richness

6 posts / 1086 viewsLast Reply

Recommended Posts

74tii - since I had the head had been re-built and have a different throttle body, KF pump, went back back through and set the baseline setup.

Was getting bas gas smoke, found the warm up regulator enrichment lever had about a 5 or 6mm opening between it and the screw, got it back close to 2.6mm, no more smoke on idle, just a little on punching the gas. (not sure whether to close the regulator up a little more)

Now the problem, idles fine cold, when it starts warming up and as the regulator is expanding, start getting a little surge on idle which right now 900-1300 rpms. (surges about 400 rpms)

After reading archives, was reading about the mixture screw inside the tuna can and that surge may be due a lean condition after warmup. Do I screw the little screw in or out to richen to see if that helps with the surge?

thanks

Ron

Share this post


Link to post
Share on other sites

According to the BMW tii injection manual (edited version I have from the registry):

"Adjust CO by turning the mixture screw OUT to raise the CO, or IN to lower it". See page 15 of this helpful manual.

Good luck - hope you can get it running correctly without the surging.

Share this post


Link to post
Share on other sites

Thanks, the manual is what I'm going by to set everything, are you making it run richer by raising or lower the CO?

Even the though manual shows a 71-73 model tuna can , I have the little screw set by what the book says, which is just verily touching the cam.

ron

Share this post


Link to post
Share on other sites

My dad was born in Rome Ga.

Anyhow to make it rich you want to close the throttle a bit. If you look at the whole deal and push the gas pedal you can see which way is open and which is closed.

Be sure the timing is dead on first though because too much advance can also cause this problem.

Share this post


Link to post
Share on other sites

screw it in to rich it - screw it out to lean it.

Keep a note book, it only takes about a quarter of turn to fix things.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.




×
×
  • Create New...

Important Information

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.