Another Weber DCOE Post

['76mintgrün'02]

6 hours ago, uai said:

So red is about yours, and blue is for for engines with more compression and more cam.

So when you have it at 10° btdc at idle <1000 you'll end up with 32° at 3200 rpm.
As the 292 is still mild and I don't know the compression you should end up in between but do not have advance below 1000 rpm and a steep curve at the beginning

 

 

Good stuff uai!  Please feel free to share/discuss any of this over on that long distributor thread I have going.  

 

I was getting some pinging in the low rpm range when the curve was close to the one you drew in red, so I brought the looped spring in sooner, which flattened it out, as seen in green (approximately) and that fixed the problem.

( The post where I shared that process can be found here https://www.bmw2002faq.com/forums/topic/178062-distributor-mechanical-advance-limiting-screws/?do=findComment&comment=1405206 )

 

Inka'd02, I am a little confused because you said you are using a Tii distributor but then said "got one", referring to uai's Ti distributor suggestion.  What is the model # of the distributor are you using?

 

OH, I just reread your post, where you said NOS Tii distributor.  As in NEW old stock; so I guess it won't have the problems I described above. 

 

I suppose the oil inside the center post could have gotten old and sticky though.

 

 

Tom

[Hans]

I'd be tempted to revisit the carbs. Did you sync with squirrel cage unit? Spanish carbs should, as I recall, be set to 3 turns out to start. I'd note the current settings, then start over at 3. I use about 33 deg at just over 3k rpm. Idles at 700 - 800 happily. Think I saw 10 deg at idle.

[Son of Marty]

Although it has noting to do with your current return to idle problem the f11 tubes you are running are used mainly for air cooled vw and won't play well in a m10 try f16 tubes you'll br happier in the long run, just my opinion anyway.   

[Chris_B]

3 hours ago, Hans said:

Spanish carbs should, as I recall, be set to 3 turns out to start.

Hans, what do you mean by this? Idle mixture? Hard to see what that has to do with his problem.

[uai]

5 hours ago, '76mintgrün'02 said:

 

 

I was getting some pinging in the low rpm range when the curve was close to the one you drew in red, so I brought the looped spring in sooner, which flattened it out, as seen in green (approximately) and that fixed the problem.

 

 

 

Tom, there is also a part where the first weight Touches the second and helps to move the second weight. When limiting travel on the first weight it will flatten the curve too. But you surely figured that out already.

[Hans]

10 hours ago, Chris_B said:

Hans, what do you mean by this? Idle mixture? Hard to see what that has to do with his problem.

I was thinking of his problem getting it to idle smoothly below 1000. Not saying it isn't something else, but idle quality can be affected by sync and mixture. And a few other things. 

OP, are they all at exactly 2.25?

[elfhearse]

The "newer" Spanish Weber DCOE have a different idle mixture screw base setting per TOPEND Technical article:

 

  "2 1/4 to 3 turns out for late style DCOES 151 and 152 with air bleed screws under the white caps."

 

complete page which I found helpful >

 

https://www.racetep.com/manufacturer/carbs-and-injection/weber/weber-carb-tuning-and-technical-info/jetting-and-tuning-downdraft-and-sidedraft-weber-carbs.html

['76mintgrün'02]

On 7/1/2020 at 5:33 PM, Inka’d02 said:

Howdy!

 

Any progress?

[Inka’d02]

1 hour ago, '76mintgrün'02 said:

 

Any progress?

Actually yes! I may have a issue with my distributor, still investigating. Thanks!

['76mintgrün'02]

Don't be such a tease.  More details please.   

[Inka’d02]

OK Guys,,

 

So here's where we are. 

 

I changed the emulsion tubes to F16.

Re checked sync, the carbs are PERFECTLY balanced.

Triple checked linkage for bind.

Idle mixtures are 3.5 turns out. 

My sticking dist. weight (which is what I thought was the issue with dist.) turned out not to be sticking.

Idles advance is 15 deg, a result of the 33 full advance. I feel like that is where the car happiest there under power. And it does run great under power.

 

I would like to add one more symptom:

The high idling issue if only an issue when it is HOT, when cold it idles really low (500-600 RPM). After about 5 min of driving idle becomes an issue.

 

I am guessing at this point distributor re-curve as most have said. thinking about purchasing a 123? thoughts?

 

Thanks, 

Andy

 

 

 

[2002Scoob]

36 minutes ago, Inka’d02 said:

The high idling issue if only an issue when it is HOT, when cold it idles really low (500-600 RPM). After about 5 min of driving idle becomes an issue.

 

That's typical DCOE.

 

You should set your idle speed and mixtures when the motor is HOT. It sounds like you're setting it up too cold.

 

Get it running, go for a solid 20-30 minute drive. Get out on the freeway and push it a little so you know things are toasty, then pull into an empty parking lot with a nice shade-tree and dial everything in. (same thing should go for your synchronisation, too)

 

And when you say 'high idle', How high? 950-1100,  Cam dependant, is normal. I like to set mine between 950-980ish.

 

DCOE's take a little bit of 'nursing' when starting from cold. It's not uncommon that you need to maintain idle with your right foot the first several minutes of driving. You'll get used to it. 

 

It's also not uncommon that the car will want to completely stall in chilly temps the first few minutes if you're not attentive. But once everything warms up (if you set your idle/mixtures warm) it'll be A-OK.

 

 

Edited July 13, 2020 by 2002Scoob

[uai]

1 hour ago, Inka’d02 said:

Idles advance is 15 deg

  that's too much try to aim for 10°

1 hour ago, Inka’d02 said:

the 33 full advance.

That's about ok

 

 

Edited July 13, 2020 by uai

[Inka’d02]

1 hour ago, 2002Scoob said:

 

That's typical DCOE.

 

You should set your idle speed and mixtures when the motor is HOT. It sounds like you're setting it up too cold.

 

Get it running, go for a solid 20-30 minute drive. Get out on the freeway and push it a little so you know things are toasty, then pull into an empty parking lot with a nice shade-tree and dial everything in. (same thing should go for your synchronisation, too)

 

And when you say 'high idle', How high? 950-1100,  Cam dependant, is normal. I like to set mine between 950-980ish.

 

DCOE's take a little bit of 'nursing' when starting from cold. It's not uncommon that you need to maintain idle with your right foot the first several minutes of driving. You'll get used to it. 

 

It's also not uncommon that the car will want to completely stall in chilly temps the first few minutes if you're not attentive. But once everything warms up (if you set your idle/mixtures warm) it'll be A-OK.

 

 

 

I am doing all of my adjustments with the car plenty warmed up. Driven for 20 or so minutes then sync'd and adjusted. 

 

Start of this post explains the idle issue:

 

"When I let off the throttle it comes down to 1500 RPM and it then takes 20 to 30 seconds to slowly creep down to 1050 or so." 

 

 

[Inka’d02]

50 minutes ago, uai said:

  that's too much try to aim for 10°

That's about ok

 

 

Ok, that will require sending it out for re-curve?