Braking problem solved! Big Thanks! - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans Advertise
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Suspension - Brakes - Steering
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 09-07-2015, 06:34 AM
jseabolt's Avatar
Registered User
 
Join Date: Nov 2011
Location: Kingsport, TN
Age: 49
Posts: 250
Wiki Edits: 0

Thanks: 4
Thanked 12 Times in 7 Posts
Braking problem solved! Big Thanks!

I may have posted this under a different section but it was in relationship to the brakes.

My 68 Fairlane 302/C4 has four manual wheel drum brakes. The problem was at red lights I'd have to put the car into park or neutral or stand on the brakes really hard to keep it from lurching forward.

I wondered if the idle speed had anything to do with it. Maybe it was engaging the torque converter when it shouldn't.

I had been using this Sunpro tune-up tach to set the idle speed but found it very inaccurate.

So I acquired this Sears engine diagnostic meter through a trade that most people said was a piece of junk. But the tachometer is spot on. I compared it to my Subaru's tach and it was right on the money.



When hooked to my Fairlane it said the idle speed was 1200 rpms in park!

With the engine was hot and fast idle circuit disengaged, I bumped the idle speed down to 550 rpms in drive / 700 rpms in park and now my lurching problem has gone away!

Anyone know what the idle speed should be set at on a 302 when the engine is cold/first started? I still think it idles too fast when the fast idle circuit is engaged. Even with my foot on the brake, it want's to bark the tires when I pull it into drive or reverse. Thanks.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 09-07-2015, 08:13 AM
delawarebill's Avatar
Registered User
 
Join Date: Mar 2009
Location: delaware
Posts: 2,373
Wiki Edits: 0

Thanks: 98
Thanked 229 Times in 221 Posts
idle rpm

around 550 to 600 is fine.. but just adjust it where it feels good in drive and foot on brake.. that number is not written in stone. never have used a tach to set it.. by ear and feel only.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 09-07-2015, 08:58 AM
jseabolt's Avatar
Registered User
 
Join Date: Nov 2011
Location: Kingsport, TN
Age: 49
Posts: 250
Wiki Edits: 0

Thanks: 4
Thanked 12 Times in 7 Posts
Quote:
Originally Posted by delawarebill View Post
around 550 to 600 is fine.. but just adjust it where it feels good in drive and foot on brake.. that number is not written in stone. never have used a tach to set it.. by ear and feel only.
Actually after I rebuilt the carburetor some 15 years ago, I did set the idle speed by ear and it sounded OK to me. I just never imagined 1200 rpms would be enough to engage the torque converter and cause braking issues. I'm used to setting up my 4 banger Fiats around 1000 rpms so the Fairlane's idle speed sounded OK to me.

I later checked it with that stupid Sunpro tune-up tach and got some funky reading. So I just left it along. Next time I'm in my box of diagnostic tools, I'm throwing that piece of junk in the garbage.
Reply With Quote Quick reply to this message
 
  #4 (permalink)  
Old 09-07-2015, 09:28 AM
RWENUTS's Avatar
Registered User
 
Join Date: Nov 2011
Location: Bowser, BC, Canada
Age: 68
Posts: 5,046
Wiki Edits: 0

Thanks: 439
Thanked 716 Times in 650 Posts
Try 1000 rpm when it's cold.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 09-07-2015, 10:01 AM
Bryan59EC's Avatar
Car? Truck? Who Cares
 

Last journal entry: First week of December
Join Date: Jun 2006
Location: San Antonio, Texas
Age: 59
Posts: 2,485
Wiki Edits: 0

Thanks: 6
Thanked 77 Times in 58 Posts
some carbs have a couple of steps to the fast idle cam

I try to set mine (high step) at around 13-1500
Low step--1000

Idle at 650-700 warm----------manual trans,
except for the Ranchero that needs a higher idle for the AC.
(will get a solenoid installed soon---have it---just haven't installed it
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 09-10-2015, 06:38 AM
jseabolt's Avatar
Registered User
 
Join Date: Nov 2011
Location: Kingsport, TN
Age: 49
Posts: 250
Wiki Edits: 0

Thanks: 4
Thanked 12 Times in 7 Posts
I haven't had a chance to check the cold idle speed but as of right now, the engine hasn't stalled at 550 rpms, idles so quiet I can't even hear it going down the road and the car is nowhere near as hard as it was before to prevent it lurching forward at red lights. I no longer have to keep both feet on the brake pedal and press hard.

I was somewhat concerned that idling at 550 rpms might cause it to idle too hot but so far the temperature gauge I added indicates the same as before, 190F. Maybe less fuel = less heat?

Mine has an Autolite 2 barrel. Whatever came on the standard 8:1 302 in 1968. Mine appears to have only 2 speeds. Fast and normal.

I don't know if this matters or not but the tubing that went to the original choke was broken at the exhaust manifold. So I went to an autopart store and found an electric choke for a Ford 2 barrel carb. I just told them I had a 1976 Granada.

I had to grind the lever down and maybe increase the depth of the slot the lever connects to the coiled unit inside the choke to make it fit flush. Then hooked it to the ignition coil. I had to adjust it several times to get it where I wanted it but so far it's worked well for 15 years.
Reply With Quote Quick reply to this message

Recent Suspension - Brakes - Steering posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Insurance
Please select your insurance company (Optional)

Log-in



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
finally solved my engine problem. stroker444 Engine 2 06-28-2010 09:26 PM
problem solved awditlady Engine 1 07-04-2006 11:41 AM
Solved my overheating problem Pony Engine 0 07-30-2004 04:26 PM
Coolant problem solved, but why? Madd Syntst Engine 3 09-16-2003 12:36 PM
oil problem solved MIKE T Engine 4 02-15-2003 07:14 PM


All times are GMT -6. The time now is 07:58 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.