GatorDog72 Posted September 29, 2017 Share Posted September 29, 2017 It couldn't hurt to give the whole carb a good cleaning. I don't like knocking other shops or mechanics, but sometimes when a part isn't in perfect condition they will tell you to just replace it. It's easier for them to just bolt on a new part, rather than take it all apart and clean/rebuild it. Unless the main body of the carb is bent or cracked, you can just replace the parts needed to get it like new. Quote Link to comment Share on other sites More sharing options...
Soler89 Posted September 29, 2017 Author Share Posted September 29, 2017 Sounds good. That'll be my project for the day once I get back from school. Maybe I'll teach my daughter how to wrench and clean. I just want to daily drive this beast without it shutting down on me. I'm so close yet so far. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted September 29, 2017 Share Posted September 29, 2017 Are you sure it's fuel starvation or metering problems in the carb? A vacuum leak could give you a shutting down condition as well. Quote Link to comment Share on other sites More sharing options...
Soler89 Posted September 29, 2017 Author Share Posted September 29, 2017 I have no idea. I'm tackling it one step at a time. I will check for leaks right now actually. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted September 29, 2017 Share Posted September 29, 2017 It's hard to diagnose unless we cover all the basics, when it's running and you place it in gear does it stay running? Probably not, cause from the sound of that video, it sounds like it's sucking vacuum somewhere. Now I believe that carb that you're using is a Holley I believe? Now are we using a stock manifold? Or an after market? Now let's not forget that the stock manifold is a spread bore and most Holley carbs are square bore, unless they're matched correctly you can end up with major vacuum sucking or leaking if you will. Ignition advance and correctly adjusting the iddle mixture screws play a huge role, but that's mostly in the final tunning. Quote Link to comment Share on other sites More sharing options...
Soler89 Posted September 29, 2017 Author Share Posted September 29, 2017 Well, I searched for a vacuum leak but couldn't really find one. I sprayed areas with carb cleaner or starter fluid and nothing really changed. From what I see, I have a Holley Carb, an edelbrock performer rpm, chrome aftermarket valve cover, and accel distributor/cap, and a top post battery. I don't think anything else is aftermarket. Quote Link to comment Share on other sites More sharing options...
Soler89 Posted September 29, 2017 Author Share Posted September 29, 2017 Currently won't stay on unless I keep the rpms up myself. Fresh gas as well. Today it only stayed on by itself once, for about 5 minutes. That was after starting it a few times and revving it up. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted September 30, 2017 Share Posted September 30, 2017 Okay, Holley carb, looks to be a square bore. Is the manifold a square bore as well? Lots of people have made that simple mistake. The mating surfaces have to match, in fact it could be sucking vacuum so drastically that it's difficult to see chance in the metering. Have you a vacuum gauge? Vacuum at idle is always high and typically ranges from 16 to 20 inches Hg in most vehicles. Â Now setting the fuel level (float level) on a Holley is tricky, I suppose you can achieve a static level without using the sight plug and make sure you're not starving or flooding. Correct manifold vacuum is essential before you can proceed, are you certain of that? What happens if you partially cover the carb throat? Quote Link to comment Share on other sites More sharing options...
Soler89 Posted October 1, 2017 Author Share Posted October 1, 2017 I will take of the carb tomorrow to check. I hope they are not matching (only because then we will know what my problem is). Also, would having an a/c car without the belt on affect anything? Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted October 1, 2017 Share Posted October 1, 2017 No it will not, Just the obvious no A/C.. also invest in an inexpensive vacuum gauge. It can be very handy for numerous things. I can't wait to see what you find out 1 Quote Link to comment Share on other sites More sharing options...
Soler89 Posted October 1, 2017 Author Share Posted October 1, 2017 Ok guys, took the carb off.the nuts holding the carb down were finger tight. That could have been a problem since they weren't torqued to spec. I will post pictures, let's me know what you guys think. Quote Link to comment Share on other sites More sharing options...
Soler89 Posted October 1, 2017 Author Share Posted October 1, 2017 Pics Quote Link to comment Share on other sites More sharing options...
Soler89 Posted October 1, 2017 Author Share Posted October 1, 2017 Also, these are vaccum ports right? The double ported photo, on the left I just plugged the trans line into it. The one next to that, as you can see in the previous photos, had a very cracked rubber cap. The third one, next to the choke, always stays open. Should these be attached to anything? I'm going to re read the manual gator sent me. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted October 1, 2017 Share Posted October 1, 2017 Well they're square bore matching, that's a step in the right direction. Nothing really jumped out at me in viewing the pictures. I will say that large (3/8" I believe) plug needs replacing it's sucking do doubt. Â Now finding the hold down hardware finger tight could also play a factor. When you get everything back together, make sure to take a vacuum reading. More importantly make sure all manifold vacuum lines are either capped or hooked up correctly. One often overlooked is the brake booster hose, and or one way valve. At times they crack and suck vacuum there as well. In a nutshell a vacuum leak equals poor carb metering. So be absolutely sure that isn't a problem before you proceed. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted October 1, 2017 Share Posted October 1, 2017 Well we are making progress. Study a bit and know the difference between ported and manifold vacuum. Once you understand that, cap everything that's not needed right this minute. Â Again..I can't stress enough the need for a vacuum gauge. An intake manifold leak could be crucial, and really trow a monkey wrench into your best efforts. And yes all not needed ports should be capped.. ported or manifold vacuum. 1 Quote Link to comment Share on other sites More sharing options...
GatorDog72 Posted October 1, 2017 Share Posted October 1, 2017 If its got a vacuum leak somewhere, you could play with the settings on the carb all day and get nowhere except very frustrated. As Rod said, a vacuum gauge is a must have for diagnosis on these older machines. Quote Link to comment Share on other sites More sharing options...
Soler89 Posted October 6, 2017 Author Share Posted October 6, 2017 Headed to the store today to get a vaccum gave. Quote Link to comment Share on other sites More sharing options...
Soler89 Posted October 6, 2017 Author Share Posted October 6, 2017 Good news guys. I took the choke off and noticed that the coil was not engaged with the lever. After fixing that, I started the car for the first time in a few days and it stayed on. Sounded a wee bit rough. I turned it off, and tried again. This time it sounded good. Turned it off, hooked up the vacuum gauge and it read GOOD ENGINE AT 2000 rpm. However, after I accelerated, the car sounded normal (not smooth) and the gauge read between 10 and 15. What does that mean? Check out the videos https://www.instagram.com/p/BZ6pxuen6VZ/ https://www.instagram.com/p/BZ6p7jUnxwQ/ Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted October 6, 2017 Share Posted October 6, 2017 I want so much to help you, but in order to do that we have to be on the same page. So it's crucial to get the the right answers to every question I pose. Â 1) Are you getting anywhere? Meaning are there changes after capping all vacuum ports. It looks like it because you have a decent reading on the gauge. Â 2) Why do you have to accelerate the vehicle from the inside? Why can't you manually do it with your hand from the engine compartment. Accelerating the carb.. manually. Â 3) Will the car stay running if you place it in gear? Assuming the transmission is hooked up and the parking brake is on, or wheels chucked. We want to place a load on the motor. Â With the help of the vacuum gauge we can now try and adjust the fuel/air mixture on the carburetor to achieve a better iddle..to see if it's metering somewhat right. Quote Link to comment Share on other sites More sharing options...
Soler89 Posted October 7, 2017 Author Share Posted October 7, 2017 1. After capping everything and fixing the choke, the car was able to start and stay on. Â 2. I was in the car because normally the car doesn't stay on for more than 1 second. Now that it stays on, I can manually accelerate it. Â 3. The car dies 95 percent of the time when engaging the transmission. If I put it in reverse, it dies after a few seconds. If I put it in drive, the car wants to jump and go, but it just dies. While in drive, I have to hold the brakes and accelerate to keep it from cutting off. Quote Link to comment Share on other sites More sharing options...
Soler89 Posted October 7, 2017 Author Share Posted October 7, 2017 Also, the carb is set to stock for the most part, and fuel level is good. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted October 7, 2017 Share Posted October 7, 2017 Great sounds like you're making progress. Now if you haven't already hook the vacuum gauge to manifold vacuum while idling, adjust the mixture screws on the carb until you see the highest vacuum setting on the gauge. It should fluctuate as you screw them in to less, and as you screw them out slowly it should rise until they'll start to drop. Do both sides until the highest reading is achive see if that fixes your iddle in gear. For now our goal is to get it to iddle in gear. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted October 7, 2017 Share Posted October 7, 2017 The above is done in park or in neutral. Â Is your ignition stock? Standard IGN (points), and if so have you set the points correctly? (Dwell) angle? Quote Link to comment Share on other sites More sharing options...
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