Kevin Wiles Posted June 29, 2011 Author Share Posted June 29, 2011 ok i thought maybe air was getting somewhere it wasnt supposed to or something.... i was gonna pick up this type of gasket to see if it helped me .... but if you say thats no problem..... i need to continue troubleshooting.. this is the kind i was thinking i needed to get: Quote Link to comment Share on other sites More sharing options...
patman Posted June 29, 2011 Share Posted June 29, 2011 That gasket should work, but I've always used the four hole style. It you sprayed around the base of the carb while it was running and it didn't suck it in, then the gasket was ok. If you've got the four hole gasket already, give it a try. Couldn't hurt. Quote Link to comment Share on other sites More sharing options...
Kevin Wiles Posted June 29, 2011 Author Share Posted June 29, 2011 i have been trying 4 days to figure this out. I just can't do it! can't figure this one out fellas..... i'm very stumped, and i'm very confused. I did find this online though.... http://forums.vintage-mustang.com/vintag...pen-square.html and then i read somewhere else where the 4 hole gaskets will just slightly improve low end torque and possibly improve mpg's. I have found nothing online that says this gap and open area created between the carb and intake will create a stumble. I guess now I pull the intake and look at the intake manifold gaskets. Because, in review, I'm definetely getting a vaccuum leak, and spraying to locate it has not turned up anything.... Quote Link to comment Share on other sites More sharing options...
Andreas Posted June 29, 2011 Share Posted June 29, 2011 Can you borrow a QJet from someone and see if that solves the problem? Quote Link to comment Share on other sites More sharing options...
Kevin Wiles Posted June 29, 2011 Author Share Posted June 29, 2011 i could but most of them have that side loading fuel line, notice this one has a front loader. See pic. My other monte has a quadrajet but its the common side loader. I would love to find someone with a known good front loader. (also see my edited response above) Quote Link to comment Share on other sites More sharing options...
patman Posted June 29, 2011 Share Posted June 29, 2011 i have been trying 4 days to figure this out. I just can't do it! can't figure this one out fellas..... i'm very stumped, and i'm very confused. I did find this online though.... http://forums.vintage-mustang.com/vintag...pen-square.html and then i read somewhere else where the 4 hole gaskets will just slightly improve low end torque and possibly improve mpg's. I have found nothing online that says this gap and open area created between the carb and intake will create a stumble. I guess now I pull the intake and look at the intake manifold gaskets. Because, in review, I'm definetely getting a vaccuum leak, and spraying to locate it has not turned up anything.... Is it a stumble or is it backfiring? It's a big difference. With a stumble I'd say it was the Q-jet, if it's a backfire I'm still going with timing/ignition issue. If it sat for awhile since the last time you started it, there's a chance that the carb gummed up. That would cause a stumble, it may run rich or lean, all kinds of things. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted June 29, 2011 Share Posted June 29, 2011 Have you tried.. Carb # & model.. perhaps the carb & manifold are mismatched. Is that even 4MV and although a qjet, it may not fit the Chevy manifold.. correctly? Carb # essential? Quote Link to comment Share on other sites More sharing options...
Kevin Wiles Posted June 29, 2011 Author Share Posted June 29, 2011 it sits and does little pops and muffled quiet misfires during idle, but backfires and spits and pops while driving especially when letting off the gas. overall just doesnt seem like its running like it should be. Quote Link to comment Share on other sites More sharing options...
KWick_70MC Posted June 29, 2011 Share Posted June 29, 2011 Out of curiosity, what was the last thing you did before this problem started?? I/e did you go for a drive and park for a while, or did it just start one day when you got in it? What if any maintenance did you possibly do? How does a rag over the carb equate to a vacum leak? I have never heard that one before.. To me it sounds like it is sucking to much air, and the rag blocks some flow Does it run better or worse with full choke and cold? when you depress the pedal, does it seem like it is lagging behind, and seems like it wants to get to higher RPM's but just can't seem to get there? Quote Link to comment Share on other sites More sharing options...
Kevin Wiles Posted June 29, 2011 Author Share Posted June 29, 2011 It has been doing this for over 2 years and I'm just now getting around to fixing it. It seems like it ran pretty good while I was in charlotte for the 10th annual fgmcc meet, but started acting up on my 2 hour drive home. And it does run BETTER while cold and with full choke. Putting the rag over the carb is just like partially choking it. And it runs better at idle with the rag. While driving seems to run just "ok" when you have the gas pedal depressed, accelerating, but as soon as you lift or go a steady speed, its pop sputter and spit. Quote Link to comment Share on other sites More sharing options...
Kevin Wiles Posted June 29, 2011 Author Share Posted June 29, 2011 ok here's what i'm doing today. I'm taking the side inlet carb off my other monte. i'm going to rig up a rubber hose that will curve around to the front inlet fuel line thats on the coke machine. if the engine runs fine on that carb, i'll be rebuilding or buying a new carb. this will help narrow it down. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted June 29, 2011 Share Posted June 29, 2011 keep us posted.. I can hardly wait to find out why it's running the way it is. Quote Link to comment Share on other sites More sharing options...
Kevin Wiles Posted June 29, 2011 Author Share Posted June 29, 2011 i can hardly wait either. i'm dying here to know. and what makes it worse is the small amount of time per day that I actually get to work on it, and the large amount of time I have per day that I have to think about it. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted June 29, 2011 Share Posted June 29, 2011 what's worst case scenario? That you gotta remove the intake? It probably needs detailing.. Quote Link to comment Share on other sites More sharing options...
Kevin Wiles Posted June 30, 2011 Author Share Posted June 30, 2011 putting the other carb on makes it run PERFECT. Now i have finally found the answer to "what is wrong with my engine". The carb. Now I have a decision to make. Buy the book everyone praises so much and learn how to rebuild this one... or simply buy a reman..... Quote Link to comment Share on other sites More sharing options...
patman Posted June 30, 2011 Share Posted June 30, 2011 Originally Posted By: Kevin Wiles i have been trying 4 days to figure this out. I just can't do it! can't figure this one out fellas..... i'm very stumped, and i'm very confused. I did find this online though.... http://forums.vintage-mustang.com/vintag...pen-square.html and then i read somewhere else where the 4 hole gaskets will just slightly improve low end torque and possibly improve mpg's. I have found nothing online that says this gap and open area created between the carb and intake will create a stumble. I guess now I pull the intake and look at the intake manifold gaskets. Because, in review, I'm definetely getting a vaccuum leak, and spraying to locate it has not turned up anything.... Is it a stumble or is it backfiring? It's a big difference. With a stumble I'd say it was the Q-jet, if it's a backfire I'm still going with timing/ignition issue. If it sat for awhile since the last time you started it, there's a chance that the carb gummed up. That would cause a stumble, it may run rich or lean, all kinds of things. What has 2 thumbs and called out the carb? This guy! haha Glad you've got it figured out. As far as what to do next, I've done both, rebuilt them and used a reman. Rebuild kits are a lot cheaper than buying a new carb. I'd probably go that route. Quote Link to comment Share on other sites More sharing options...
wallaby Posted June 30, 2011 Share Posted June 30, 2011 The rebuild isn't hard. Is it possible that the old carb just needs some adjusting? Sometimes the idle adjustment screws get mis-adjusted...like one way out abd the other way in, and although it seems to balance out in the end, it causes poor running. If external adjustments can't fix the problem, then it's a candidate for rebuild. I vote for the rebuild before buying a reman. Quote Link to comment Share on other sites More sharing options...
Andreas Posted June 30, 2011 Share Posted June 30, 2011 Good to hear you found it! A few years ago, the fuel inlet threads were stripped on my old QJet, so I bought a reman QJet from Summit Racing for my 72 Monte. It was a great product, just bolt on and go... Quote Link to comment Share on other sites More sharing options...
KWick_70MC Posted June 30, 2011 Share Posted June 30, 2011 Glad to hear that you found the problem.. Where did you get the carb that is on it now?? I was having problems with a Q-Jet that I was rebuilding to only find out that it was two different 4 barrels made into one, and it caused the carb not to work right. Quote Link to comment Share on other sites More sharing options...
Kevin Wiles Posted June 30, 2011 Author Share Posted June 30, 2011 the carb thats on it now, came with the engine i bought used. it used to run right, so i'm assuming it will run right again with some work. i bought the "how to rebuild and modify rochester quadrajet carbs" book by Ruggles. It should come in soon, I'll start by reading that. Quote Link to comment Share on other sites More sharing options...
Monte7071 Posted July 1, 2011 Share Posted July 1, 2011 If you rebuild it make sure you or someone else puts new bushings in it. http://www.cliffshighperformance.com/bushings.html# Quote Link to comment Share on other sites More sharing options...
FastClass Posted July 1, 2011 Share Posted July 1, 2011 Wish I had thought of it sooner. Friend`s 1st Gen Blazer had suffered from similar problems. Turned out to be the bushings. Quote Link to comment Share on other sites More sharing options...
Jared Richey Posted July 1, 2011 Share Posted July 1, 2011 We're gonna learn how to rebuild a Q-Jet. Quote Link to comment Share on other sites More sharing options...
patman Posted July 1, 2011 Share Posted July 1, 2011 We're gonna learn how to rebuild a Q-Jet. Quote Link to comment Share on other sites More sharing options...
Monte7071 Posted July 1, 2011 Share Posted July 1, 2011 I would suggest beer after the rebuild lol. Quote Link to comment Share on other sites More sharing options...
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