Ferrari Mailing List: Re: Quirky stuff, 308 idle woes

[Larry T (l02turner]

This may not have anything at all to do with your Ferrari but during the 70s, some manufacturers often resorted to vacuum pots that slowed the return to  final idle speed, often stopping at 1500 rpm then 1000 rpm and finally 850-900 rpm.    They were very frustrating when not working properly...

Doesn't explain why it would only work with the air cleaner in place - unless it's part of the Air Cleaner?

LarryT

On 3/10/2013 7:08 PM, Rick wrote:

When just sitting the garage the cam is completely released BUT I can't guarantee that once nicely hot its not malfunctioning.  I'll get my bore scope back this week and will be able to see its position.

Another great suggestion, and pure common sense, is to measure airflow on each choke when its misbehaving.  That will tell me if one carb is causing the problem, or if its more throttle linkage related.

-rick

Sent from my Verizon Wireless 4G LTE Smartphone

-------- Original message --------
From: "Robert W. Garven Jr." <rgarven [at] gmail.com>
Date: 03/10/2013 2:34 PM (GMT-06:00)
To: Rick <rolindsay [at] yahoo.com>
Cc: The FerrariList <ferrari [at] ferrarilist.com>
Subject: Re: [Ferrari] Quirky stuff, 308 idle woes


Rick,

Could it be the fast idle cam? I set mine not to work, but it never gets cold here 75 today......

Rob
Robert W. Garven Jr.
rgarven [at] gmail.com


"The Ferrari is a dream - people dream of owning this special vehicle and for most people it will remain a dream apart from for those lucky few." Enzo Ferrari






On Mar 10, 2013, at 6:24 AM, Rick wrote:

Further to the 308 idle-down issue; a few more observations and realizations.

1. The car only has the idle-down problem when at operating temperature. I just realized this (duh) because it only happens on a drive - and after - when the engine bay is hot.

2. I should have been more clear.  The problem happens when the air cleaner BASE is on the carbs, but that may be a spurious and misleading data point.

3. A friend has my bore scope camera and he's presently in Europe.  When he returns I'll be able to see all the linkage movement with the air cleaner base on.

4. Since this problem acts like a vacuum leak - kinda - I'll temporarily disconnect and plug the brake booster vacuum line ...just as a methodical test.

5. Perhaps the issue is NOT the air cleaner but a heat issue, and the engine only gets to operating temperature with the cleaner on.  I won't drive it with cleaner off.  Webers spit too much fuel vapor to drive with the air cleaner off.  Serious fire hazard.

6. I think I will fashon a long wire with a hook end (read: coat hanger) to pull gently, each carb linkage in turn, to its idle stop to see if anything might be binding once hot. At no-load, even a tiny error in throttle position can make a big difference.

7. Yes, time and detective work is needed.  FWIW, the car runs fantasticly.  I just need to correct this pesky idle-down problem.  And heat may be the clue to finding the solution.

My thanks to those offering advice.

-rick
Sent from my Verizon Wireless 4G LTE Smartphone
_________________________________________________________________
To unsubscribe or modify your subscription options, please visit:
http://lists.ferrarilist.com/mailman/options/ferrari/rgarven%40gmail.com

Sponsored by BooyahMedia.com
and F1 Headlines
http://www.F1Headlines.com/

_________________________________________________________________
To unsubscribe or modify your subscription options, please visit:
http://lists.ferrarilist.com/mailman/options/ferrari/l02turner%40comcast.net

Sponsored by BooyahMedia.com 
and F1 Headlines
http://www.F1Headlines.com/