Diesel after shutdown! Do I need to drill throttle plates?? - Team Camaro Tech
Engine General Engine Discussion.

 
LinkBack Thread Tools Display Modes
post #1 of 9 (permalink) Old Mar 9th, 03, 07:01 PM Thread Starter
 
Join Date: Sep 2000
Location: canyon country,California
Posts: 29
Post

Hi Fellas,

I have a 350 0.040 trw flat top,186 casting 2.02 1.60 64cc,comp cams 280h hyd flat tappet,weiand stealth intake,600 cfm edelbrock 1405 orange step up springs,msd 8365 ready to run dist with blue springs and the 18 deg cent advance bushing.Its in a 68 4 spd camaro everything is fairly fresh comp test was 180 psi on all 8.The car runs pretty strong but I cant get it to idle for horse duckey at 18 deg initial and ported vacuum without the thing dieseling at shutdown.Coolant temp is 160 to 170 idle at 800 rpm to 900 rpm 8 in vacuum almost rock steady needle.I do get some response from the mixture screws and when I pull carb to check transfer slot it seems close to 0.020 but dont have measuring equip.Car likes to idle at 25 deg initial do i need to drill the throttle plates or further limit the cent advance somehow ....

thanks for your thoughts

68 camaro 5.7rod 406 M20 muncie
LongRod406 is offline  
Sponsored Links
Advertisement
 
post #2 of 9 (permalink) Old Mar 10th, 03, 02:06 AM
Super Moderator
Bess-68's rule
 
Everett#2390's Avatar
 
Join Date: Sep 2000
Location: Va Beach VA
Posts: 31,728
Garage
Cool

Nice combo you have and it reads like it runs pretty well.

I think it s horse puckey rather than horse duckey......LOL

I would probably change the vacuum advance from ported to full time. This would allow reduced basic timing at start-up and shutdown.

If all else fails, you can leave the trans in 4th gear, foot on the brake and let out on the clutch when the key is turned off. Dieseling hates loads.

Are you sure the mark on the harmonic balancer and the timing pointer match with #1 TDC? Hopefully you don't have a '69 or later h/b with a 68 or older timing cover/pointer.

Give a man a rescued dog for the health of both their souls. May 2017 ROTM Winner - Thank you!
'
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
CUBS - 2016 World Series Champions - Thank you, Joe Madden enjoy your next chapter.
Everett#2390 is offline  
post #3 of 9 (permalink) Old Mar 10th, 03, 06:47 AM
Senior Tech
 
Join Date: Feb 2001
Location: Concord Cal. USA
Posts: 2,664
Post

Engines diesel because of retarded timing and too lean an idle circuit. You timing definately isn't retarded so if the idle isn't too high it is probabily lean in the idle circuit.
oger is offline  
 
post #4 of 9 (permalink) Old Mar 10th, 03, 11:30 AM
Senior Tech
 
Join Date: Sep 2002
Location: Greensboro, NC, USA
Posts: 109
Post

Longrod406,

I have a very similar setup, and had the same problem. I played with everything but it would still happen. Either I would have to set the idle REALLY low, or it would diesel. I finally changed the step-up springs (EDL part # 1464) to the seven inch spring and it never happened again. Have you tried the 7 or 8 inch springs (pink or plain, respectively)?

It sounds like you already changed them (I thought stock were yellow) so you probably have the kit. Sorry to waste your time if you already tried the others, but that's what did it for me.

Mike J.
67 406ci named "Gideon"
Gideon is offline  
post #5 of 9 (permalink) Old Mar 10th, 03, 01:15 PM
Tech Team
 
Join Date: Apr 2001
Location: Bethpage, Tn
Posts: 69
Angry

You know how sometimes you can have a problem and after awhile it will just go away. Well, my '69 would do that same thing. Its a mild 350 and automatic. When running 87 octane, it done it all the time. I started running the 92 in it and it stopped all togather. Later on in a pinch, I put the 87 back in it, and it started again. After I ran that tank out, I put the 92 back in and have never had the problem again. This could have absolutely nothing to do about the octane, but it sure seem like the higher octane helped. Just my .02 worth. Hope it helped.
speedball1969 is offline  
post #6 of 9 (permalink) Old Mar 10th, 03, 06:55 PM Thread Starter
 
Join Date: Sep 2000
Location: canyon country,California
Posts: 29
Cool

Hey thanks everyone for sharing your thoughts.I found a small vac leak at phenolic spacer to manifold got new felpro on top and bottom of spacer no more vac leak reset everything and so far no diesel.Next dilema is to find the tapping or ticking sound i hear in car while driving after she reaches full temp definately not exhaust
leak its intermitten which i dont understand all ehaust sealed tight!!!

68 camaro 5.7rod 406 M20 muncie
LongRod406 is offline  
post #7 of 9 (permalink) Old Mar 10th, 03, 07:29 PM
Retired
Jim
 
click's Avatar
 
Join Date: Jun 2001
Location: Central Minnesota
Posts: 15,980
Post

Could be the wife's finger nails tapping on the dash wondering when you are gonna quit messing with it and just take her out to dinner [img]graemlins/waving.gif[/img]

Click..is Jim..former owner of a 69RS-LM1 350/255 - 700r
"There will come a time when you believe everything is finished,
That will be the beginning." Louis L'Amour
click is offline  
post #8 of 9 (permalink) Old Mar 11th, 03, 01:49 AM
Super Moderator
Bess-68's rule
 
Everett#2390's Avatar
 
Join Date: Sep 2000
Location: Va Beach VA
Posts: 31,728
Garage
Cool

Nice burn, click.......... [img]graemlins/thumbsup.gif[/img]

Give a man a rescued dog for the health of both their souls. May 2017 ROTM Winner - Thank you!
'
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
CUBS - 2016 World Series Champions - Thank you, Joe Madden enjoy your next chapter.
Everett#2390 is offline  
post #9 of 9 (permalink) Old Mar 13th, 03, 09:53 PM
Senior Tech
Lonnie
 
Join Date: Mar 2000
Location: Mesa, AZ
Posts: 744
Post

When the key is turned "off" there is no longer any voltage getting to the ignition, so retarded or advanced timing would make no difference, since there is no longer any spark to the spark plugs.

Usually, the fuel is being ignited by hot spots in the combustion area, hence the term "dieseling", low octane fuel will make the condition worse.

67 Camaro [email protected], [email protected], 1.455 60ft 421sbc
Lonnie67 is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Team Camaro Tech forums, you must first register.
Please enter your desired user 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.
NOTE we receive a lot of registrations with bad email addresses. IF you do not receive your confirmation email you will not be able to post. contact support and we will try and help.
Be sure you enter a valid email address and check your spam folder as well.



Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



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

 
For the best viewing experience please update your browser to Google Chrome