Moparchat - Home of MOPAR enthusiasts worldwide!



Go Back   Moparchat - Home of MOPAR enthusiasts worldwide! > Technical Forums > Performance Talk

Click here to search for Mopar cars and parts for sale.


Reply
 
Thread Tools Display Modes
  #1  
Old 02-23-2003, 12:13 AM
Bigfoot Bigfoot is offline
Inactive User
 
Join Date: May 2002
Location: Edmonton/Alberta
Posts: 178
Default Thermoquad running rough on secondaries

I had a problem with my thermoquad late last year and actually it was a week fuel pump that was my headache. I changed the pump and put a new filter and everything was back to normal till last Friday. The car starts up fine and idles good and as long as I am in the primary bores everything is good. I can drive around town with no hesitation and is as smooth as glass idling. As soon as I open up the secondaries she jumps to life as it should and when I let off on the gas it bucks and hesitates and runs horrible. It will continue like this for a long time and will not smooth out as before until I stop and turn the car off. I let it sit for 20 seconds and then after cranking for what seems like forever, it starts again and idles smoothly. Here is my thinking. When I open up the secondaries either the secondaries are being held open after the run and adding to much air to the carb, or somehow fuel is continuing to be dumped down the secondaries when there shouldn’t be. Or could it be a combination of the two. Just as I type this I was thinking next time I open it up I should pull over to the side of the road and pop the air cleaner to see it the secondaries are still part of the way open. Any thoughts
Reply With Quote
  #2  
Old 02-23-2003, 11:34 AM
jelsr jelsr is offline
Inactive User
 
Join Date: Dec 2001
Location: Dighton, Kansas
Age: 84
Posts: 1,253
Default

Difficult to tell over the net. If, after the long cranking period, the exhaust gives a puff of black smoke when it starts it was flooded. I suppose the sec's could be sticking and when you let up on the throttle the air valve closes and acts like a choke. This is strictly a SWAG*! Like you mentioned, jump out with flashlight in hand and eyeball the situation.

*Scientific wild a$$ed guess
Reply With Quote
  #3  
Old 02-23-2003, 02:12 PM
David Wiser's Avatar
David Wiser David Wiser is offline
Inactive User
 
Join Date: Sep 2002
Location: Las Vegas, NV
Age: 77
Posts: 24
Default

Bigfoot, sorry to hear about your ThermoQuad problem. I feel guilty, I think I just got my problem cured. (See my latest update on float level question).
I don't have any experience with your problem, except, it sure does seem like some linkage is sticking.

Keep us updated.
Reply With Quote
  #4  
Old 02-23-2003, 08:55 PM
rustycowl rustycowl is offline
Inactive User
 
Join Date: Dec 2002
Location: seattle,WA
Posts: 167
Default yup

Try new floats and needles and seats. Be very careful blowing out all the passages with compressed air. Don't forget to reinstall the sec flow diverter.
Reply With Quote
  #5  
Old 02-23-2003, 10:12 PM
David Wiser's Avatar
David Wiser David Wiser is offline
Inactive User
 
Join Date: Sep 2002
Location: Las Vegas, NV
Age: 77
Posts: 24
Default

What is the secondary flow diverter ?
Reply With Quote
  #6  
Old 02-24-2003, 01:12 PM
rustycowl rustycowl is offline
Inactive User
 
Join Date: Dec 2002
Location: seattle,WA
Posts: 167
Default oh

It's that thin flat plate that hangs vertically in the sec venturi area of the bowl, just below the bowl cover. If you forget to reinstall it, the airflow thru the sec.'s gets real confused!
Reply With Quote
  #7  
Old 02-24-2003, 08:03 PM
Bigfoot Bigfoot is offline
Inactive User
 
Join Date: May 2002
Location: Edmonton/Alberta
Posts: 178
Default

I made sure the diverter was there, it only can go in one way. I did a run on the way home and when I popped the air cleaner the secondaries were closed all the way, so it must be extra fuel somehow. I will need to read up on how the secondaries actually work and try and figure it out.
Reply With Quote
  #8  
Old 02-26-2003, 09:40 PM
dynorad dynorad is offline
Inactive User
 
Join Date: Oct 2001
Location: Niwot, CO
Posts: 114
Default

The only way for fuel to be pulled out of the secondaries is for the butterflys to be open below it. Vacuum is what pulls the fuel out.
Reply With Quote
  #9  
Old 02-26-2003, 11:45 PM
Bigfoot Bigfoot is offline
Inactive User
 
Join Date: May 2002
Location: Edmonton/Alberta
Posts: 178
Default

Duh! I never thought of that. I will make another run tomarrow and when I pop the air cleaner I will try and see if the mechanical link to the secondaries is binding on something and keeping them open a slight bit.
Reply With Quote
  #10  
Old 02-27-2003, 12:25 PM
rustycowl rustycowl is offline
Inactive User
 
Join Date: Dec 2002
Location: seattle,WA
Posts: 167
Default more

If you pull the top off and find any crap in the bottom of the bowl, I am thinking all the fuel passages and air bleeds have crap in them, too. See, earlier post.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
rough running ehostler Diesel & Turbo Diesel Chat 11 12-27-2009 02:18 PM
running rough power_ram Ram Truck Chat 1 12-09-2007 01:54 PM
Rough running 400 PaulH Performance Talk 3 07-15-2006 09:19 AM
Rough Running 2.2???? Duster_340 Front Wheel Drive Chat 5 06-27-2002 11:07 AM
running but rough Youngin Ram Truck Chat 17 08-19-2001 10:56 AM




All times are GMT -4. The time now is 10:19 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
. . . . .