rochester carb problem. - Team Camaro Tech
Engine General Engine Discussion.

 
LinkBack Thread Tools Display Modes
post #1 of 9 (permalink) Old Aug 2nd, 09, 10:37 AM Thread Starter
Gold Lifetime Member
Harry
 
dawg's Avatar
 
Join Date: Mar 2004
Location: Colebrook CT.
Posts: 4,029
rochester carb problem.

I got a quadrajet carb on my 69 corvette.
Im not too familiar with quadra sucks but after pulling out of storage I took it for a ride.
everything worked fine
punching it and secondaries opened no problem.
after 15 mins of driving I filled tank with fresh gas.
upon startup engine ran rough and breaking up.
driving it improved the breaking up and primaries worked normally.
upon opening secondaries It backfires and pops out of secondary side
changed filters upon getting home and it still pops and backfires.
(this is original carb with 58000 miles on the car)
thks for the help!


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

434 stroker
US Navy retired

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
dawg is offline  
Sponsored Links
Advertisement
 
post #2 of 9 (permalink) Old Aug 2nd, 09, 12:38 PM
Senior Tech
clayton hicker
 
Join Date: Nov 2007
Location: selma,oregon
Posts: 445
Re: rochester carb problem.

sounds like you didnt get fresh gas in it in time.dirt got in there and plugging something up

clayton hicker
bikedude3 is offline  
post #3 of 9 (permalink) Old Aug 2nd, 09, 01:24 PM Thread Starter
Gold Lifetime Member
Harry
 
dawg's Avatar
 
Join Date: Mar 2004
Location: Colebrook CT.
Posts: 4,029
Re: rochester carb problem.

yeah Im concidering either replace carb or rebuild it.
(bushings seem a bit loose too)


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

434 stroker
US Navy retired

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
dawg is offline  
 
post #4 of 9 (permalink) Old Aug 2nd, 09, 01:47 PM
Super Moderator
Bess-68's rule
 
Everett#2390's Avatar
 
Join Date: Sep 2000
Location: Va Beach VA
Posts: 31,750
Garage
Re: rochester carb problem.

Might check point gap just to make sure it hasn't changed and the centifugal weights to make sure they extend & retract.
Rebuild the carb on it including replacing the shaft bushings. You'll be glad you did. JMT's.

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 Ö enjoy your next chapter.
Everett#2390 is offline  
post #5 of 9 (permalink) Old Aug 2nd, 09, 02:04 PM Thread Starter
Gold Lifetime Member
Harry
 
dawg's Avatar
 
Join Date: Mar 2004
Location: Colebrook CT.
Posts: 4,029
Re: rochester carb problem.

I have pertronics conversion (no more points)
I also checked the weighs and they work good.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

434 stroker
US Navy retired

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
dawg is offline  
post #6 of 9 (permalink) Old Aug 2nd, 09, 08:09 PM
Senior Tech
Wes
 
Join Date: Dec 2003
Location: Leander, TX
Posts: 2,762
Re: rochester carb problem.

Back-firing through the carb? That's likely a timing problem. Check to see if the distributor has walked on you. Then check for a cracked cap or wires that are crossfiring.

Also, cute name for the beloved q-jet ("quadra sucks") but I think if you spent some time learning how a q-jet works and how to tune it, you'd find it to be a beautifully engineered piece of equipment.

FWIW
Straight-line-69 is offline  
post #7 of 9 (permalink) Old Aug 2nd, 09, 08:25 PM
Senior Tech
Jon
 
Join Date: Dec 2002
Location: back in the Hew-Hess-Hay
Posts: 5,755
Re: rochester carb problem.

If everything else checks out, pull the valve covers and make sure you don't have a cam going away. Flat cams can cause what you're describing too.....

Jon N

The only reason someone would want insurance is if they want to pay someone elses bills or want someone else to pay their bills.
dyno jonn is offline  
post #8 of 9 (permalink) Old Aug 3rd, 09, 07:01 AM Thread Starter
Gold Lifetime Member
Harry
 
dawg's Avatar
 
Join Date: Mar 2004
Location: Colebrook CT.
Posts: 4,029
Re: rochester carb problem.

put vacum gage on full vacum and holds stready at 18"
if lobe was going the needle would be swinging all over the place.
I just think the carb got some crap in it.
the big GF-432 prefilter had all kinds of crap in it (rust etc)


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

434 stroker
US Navy retired

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Last edited by dawg; Aug 3rd, 09 at 07:28 AM.
dawg is offline  
post #9 of 9 (permalink) Old Aug 4th, 09, 04:12 PM Thread Starter
Gold Lifetime Member
Harry
 
dawg's Avatar
 
Join Date: Mar 2004
Location: Colebrook CT.
Posts: 4,029
Re: rochester carb problem.

well pulled the carb and i found the base gasket leaking on the secondary side.
also there is a crapload of black soot etc. at the bottom of the intake plenum.
talked to a local mechanic and he said bad gas and the gasket leak would cause backfire for sure.
carb must be rebuilt anyhow.
Its my wifes vette and she drives it like an ol lady never getting into the secondaries ever.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

434 stroker
US Navy retired

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
dawg 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