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1968 Q-jet 4MV leaking

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Old Nov 13, 2016 | 10:05 AM
  #1  
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Default 1968 Q-jet 4MV leaking

hi,
i'm restoring 1968 BB and have issue of carburator leaking fuel from top and sides.
please see attached pictures (marked in red circles)







any help or links on how to fix this issue greatly appreciated!
alex
Old Nov 13, 2016 | 12:10 PM
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From: At my Bar drinking and wrenching in Lafayette Colorado
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The carb is leaking fuel out the throttle shafts because it is dribbling fuel out of the main discharge nozzles after shutdown. This drops fuel down onto the throttle blades, and it wicks out the shafts and onto the manifold. The reason this is happening is that your fuel level is way too high, as evidenced by fuel coming out the accel pump hole. This can be caused by any one or more of the following issues:
  • Bad float
  • Wrong Float
  • High Float
  • Bent/damaged float pin
  • Leaking needle/seat
  • Damaged seat threads
  • Float arms binding on power piston tower
  • High fuel pressure
  • Float needle clip installed backwards
...just to mention a few. The bottom line is that the carb needs a complete disassembly, inspection, and rebuild by someone qualified to do it correctly.

Lars
Old Nov 13, 2016 | 12:28 PM
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Lars,
thank you for reply.
i will get expert to disassemble and rebuiid it.
Old Nov 13, 2016 | 12:42 PM
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Lars is one of only a few experts around to look after your Q-jet.
Just saying, even with the Canadian Peso, it's probably worth sending it south, several of the rebuilders left in TO are fairly barbaric.
M
Old Nov 13, 2016 | 12:56 PM
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M/Lars,
indeed
http://www.crankshaftcoalition.com/w...4MV_carburetor
http://www.gmcmi.com/wp-content/uplo...ice-Manual.pdf

look complicated and intimidating for newbie... which shop south of TO would you recommend ?
thnx,
alex

Last edited by aldem; Nov 13, 2016 at 01:06 PM.
Old Nov 13, 2016 | 03:02 PM
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There has to be some other people around in nameless shops that still understand how these are actually supposed to work but it's pretty hit and miss as to who works on your card after your drop it off...

Lars, Henry Olsen (Ole’s Carb and Electric) or Cliff Ruggle are all pretty dafe bets.

Mine went to Lars

I'm not intimidated by much (probably should be) and have had mine all apart more than once after switching back from a holley.
Last time it needed REAL work and it went to Lars.
Worth every cent.

Can't say if he's taking on any work but shoot him an email
Lars Grimsrud <v8fastcars@msn.com>

M
Old Nov 13, 2016 | 03:39 PM
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From: At my Bar drinking and wrenching in Lafayette Colorado
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I have 2 Q-Jets from Canada in my workshop right now. I get them sent down from up north pretty regularly. E-mail me for info on services.

Lars
V8FastCars@msn.com
Old Nov 15, 2016 | 07:34 AM
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Lars,
thank you for offer.
i've sent you email to V8FastCars@msn.com as your local storage on this forum full
alex
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Old Jan 1, 2017 | 10:33 AM
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Lars,
thank you very much for fixing my carburetor.
happy new 2017!
alex
Old Jan 1, 2017 | 05:25 PM
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From: At my Bar drinking and wrenching in Lafayette Colorado
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I hope you get some fun and trouble-free performance out of it!

Lars
Old Jan 1, 2017 | 08:03 PM
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Yet, another satisfied customer....
Old Oct 5, 2024 | 02:58 PM
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Anyone know if Lars still rebuilding carbs?
Old Oct 5, 2024 | 04:34 PM
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Originally Posted by ricoman
Anyone know if Lars still rebuilding carbs?
Why don’t you send him an email and ask him?
Old Oct 5, 2024 | 04:46 PM
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Originally Posted by ricoman
Anyone know if Lars still rebuilding carbs?
Yes he is. I emailed him a few weeks ago due to a rumor that he wasn't.
Old Oct 5, 2024 | 05:15 PM
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Originally Posted by Piersonpie
Why don’t you send him an email and ask him?
I did...thanks...
Old Oct 5, 2024 | 05:17 PM
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THANKS...I did email him...but figured it might take a few days to reply....but good to know...!
Not sure of cost to rebuild,new is $475....and can have it in a day...
Old Oct 5, 2024 | 06:48 PM
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Originally Posted by ricoman
THANKS...I did email him...but figured it might take a few days to reply....but good to know...!
Not sure of cost to rebuild,new is $475....and can have it in a day...
Only new ones are Chinese made, don't do it.

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Old Oct 5, 2024 | 07:51 PM
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THANKS..!!! But Isnt everything now... sad..!! I did notice many places are selling ones that "Look" like originals....lots on Ebay...$200 cheaper is first sign since every legit site is $477...and 2nd is they are not even marked Holley...
I did screw up and over tighten the bowl bolts,and now its really leaking so just going to buy one direct from Holley....and then have this one rebuilt for a spare....Dont want downtime now,only get to drive it few months in rainy WA. state...and Oct is a good month for driving
Old Oct 5, 2024 | 08:03 PM
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Originally Posted by ricoman
THANKS..!!! But Isnt everything now... sad..!! I did notice many places are selling ones that "Look" like originals....lots on Ebay...$200 cheaper is first sign since every legit site is $477...and 2nd is they are not even marked Holley...
I did screw up and over tighten the bowl bolts,and now its really leaking so just going to buy one direct from Holley....and then have this one rebuilt for a spare....Dont want downtime now,only get to drive it few months in rainy WA. state...and Oct is a good month for driving
How did Holley get into this thread? The thread from 7 years ago is about a Quadrajet.
Old Oct 5, 2024 | 10:08 PM
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Only because I searched Holley leaking problems...sorry if I mis-stepped rules...have been on site for years,but have not used for many,,,,still trying to learn the new rules...I saw the thread and photots on the Quadrajet post and looked like it addressed my issues...gain,sorry if in wrong section.....



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