Well I'm quickly loosing my patience and feel like I'm slowly loosing my mind. 1st problem . My Edelbrock Performer Carb (600 cfm on a 69 Chev 350) Had it around 10 years now without a glitch and low and be hold unhappy things are brewin. 10 years seems like a good while and it's understandable to have a problem by now, I suppose... About 2 -3 months back it seems like the choke was sticking (or something). Basically the Chev would start for a week maybe a few days more...and then the it wouldn't start. Tried holding the choke butterfly open w/ a screwdriver...VROOOOM!! Seemed to work at first. So, I took a friend's advise and got a new choke for the Edelbrock about 2 weeks ago. Problem is still there and very unpredictable. And worse yet, the screwdriver trick won't work anymore. Tried leaning out the choke too many times for me to remember which seemed to help the perfomance and possibly the starting for at least a few days..Then last Sundy night, I spray a very healthy amount of Gumout inside and out ....running very very nice....This morning nothing and the choke was closed... So I try to remind myself "okay if it's cold outside, which it is, the choke should be closed for the engine to start" Not workin. I try holding the choke open w/ a small screwdriver again....nothing....wait...then I try every dumb thing I can think of since this is my daily driver and I have to get to work(open the gas tank for air....tap the this , tap that .....wait a few minutes....try starting again.....nothing........swear .....curse....swear curse swear curse swear curse..............) and then I try again and still nothing................................. time to take the bus. Damnit. After work, Dad and I try lookin into it. Now , not only will the sumbitch still not start , but somehow during the last 8 or 9 hours, my fairly new HEI (got it around October) sounds magically out of time and it sounds like some sort of vaccum sneeze during that pause (from what would be related to timing problems?). Now I have a 2nd problem to deal with....with no warning WTF?? Vaccum Hoses are all intact as they were the last 2 days when it was starting up w/no problem and running very strong and smooth. Checked to see if the dizzy was loose...nope . Very snug and secure as it has been since October and it seems to be about the same position it's been ....no signs of being tampered with. ......... Anyone have any advise...something I'm missing?
I guess I figured , in a trusting naive sort of way, that the dizzy /coil wouldn't be suspect since it's really not that old (??) The only detail tied in, that I've been somewhat concerned about is that it's all stock for a 75 350 Chev and the coil was pretty inexpensive...I think it cost about $15 . ....I'm not sure what how much life to expect.....I really don't drive it hard very often. Problem seems to happen mostly @ night / early morining when it's cold...... But not all the time, which is a big factor in why it's so frustrating. So I don't know if weather is a factor or not.....
1: after ten years that carb is probably ready for a rebuild kit. 2: check under the cap, if there is too much resistance in the ignition circuit (poor grounding is common) there will be scale on the posts.
Mmmmkay - First, you've chosen some of the most reliable of components, so you're doing good. GM HEI and Edelbrock 600s are good parts. So, what's the deal? Here's a couple ideas. First, some basics. Ensure the carb is squirting fuel when you operate the linkage. Make sure it's getting sufficient fuel from the pump. Make sure the fuel filter is clean, unclogged, and flowing freely. Then, check the wiring to the HEI. You've only got a couple wires to check - first, the power wire that runs to the "BAT" terminal on the side of the distributor. This powers up the whole unit, and if it's not a good conection, nothing will work. Chase the wire to it's source (should be 12V keyed) and see if all is well on both ends. HEI have internal coils, so odds are it's okay. Secondly, the module in the HEI. As mentioned, it's a solid state part which can be tested, but looking at it will tell you nothing. They're not pricey, so if it tests bad you're not out too much dough. If the HEI checks out and makes good spark when you pull a plug wire (hold it with pliers or something so you don't zap your ass), then it's working okay. The timing hasn't been messed with and you know it worked before, so don't fuck with it. Okay - the carb. If it's shooting fuel and being fed fuel, then you may have a float issue. Get the top of the carb off and check the floats. There are books to show you how to do this, but it's not hard even if you've never done it before. Keep the screws organized, since different lengths must go in their specified holes. If the carb floats are indeed floating, check the fuel inlet for any obstruction. Basically, look everything over and compare side-to-side for anything unusual. These carbs are quite bulletproof, so anythuing bad should stick out liek a sore thumb. With regard to the choke, I'd recommend getting it completely functional again. It's not tough to do and it really helps the engine start easier. The screwdriver trick is more of a cure for flooding and an over-rich condition. It should not be used every time the car is fired, since it leans out the mix so much. It's a band-aid for another issue, and it's not the choke. The choke should be closed when the car is fired, and if it starts easier in the Colorado cold with the choke held open, you've got other issues. If you can't figure it out, call my pal Jay Kidwell at Mile High Performance. He's local to you and tell him Scott from PHR/Engine Masters sent you over. He'll treat you right.
You said something that caught my ear- "started and ran fine"" then not starting"- "mostly when cold on monings and late night".......sounds like ten years of good use,,its just been good too long.....you need an accelerator pump,its worn out- put a kit in it.propping the choke will help if it WAS flooded- but on the other hand it would not start with no "squirt' from the accel pump and opening the choke would let in too much cold air for a quick start..
I was thinking the same about the carb....short on funds and patience so I haven't been excited about the idea... I guess I'll try investigating further this weekend. Thanks for all the suggestions
Sorry the reply before was from early this morning prior to Scotch and choprods help....I thought my comments acctually posted and I guess they never did So with the well detailed advise you all have given, I think I should sound a bit more positive...THANK YOU VERY MUCH YOU GUYS ARE GREAT You've definitely put things into better perspective for me ...again thank you. Scotch I'm very happy you stood by the same idea I had with the timing...that was just drivin me nuts last night...And I think I'll go to you buddys shop even if I can figure this out with what I've got so far...Sounds like a good shop and I know I haven't been there yet. Choprods, I was actually @ the Summit racing site today and saw some info on Edelbrock accel. pumps and started thinkin that could be part of my problem. I've heard a lot of good things about these Performer Series carbs (easy to work on / tune/ diagnose etc) and callin a spade for spade I've just had cold feet about tearin the thing apart. So maybe I'll see what kind of progress Saturday brings. I'll let you all know what happends
FYI here's Mile High Performance's contact info: JAY KIDWELL/CRAIG BROOKS MILE HIGH PERFORMANCE/COMPETITION ENGINE CONCEPTS 2101 W. Cornell Ave., Dept. PHR Englewood, CO 80110 (303) 781-1118
Okay after all that I decided to rebuild the Edelbrock myself and despite my nerves telling me a SNAFU was just around the corner....the rebuild went fine The only concern I have is the unpredictable hesitation on accelleration. Actually it's come damn close to flat out dying the last two nights, but I save it by pumpin the gas and the v8 will kick back in.......I keep thinkin it's the choke but I made some referance marks on the choke to come back to during the rebuild hoping I'd at least be " in the ballpark" . Initially that seemed to work... It runs fine, not really any backfire (that I can hear of anyway...glasspacks might be hidin somethin) and I'm just going by ear with the air fuel mix... I'm just havin some issues with it boggin out when I hit the gas Other than that, things are much better Thanks again to everyone that gave their 2 cents
Bogging when you hit the pedal is something to do with the accel pump. Check that you didn't fold the pump diaphram when you redid the carb. I think there is a little ball involved as a check valve also. Either the ball or the diaphram is not right. Oh yeah- maybe the rod for the pump is in the wrong hole.
Take a good look at the contact button that goes from the center of the cap down to the rotor. Mine wore down and started arcing which took out the coil pack. I had the same problems as you and also thought it was the carb. One note about the carb. If it's a straight out of the box Edelbrock 600 then it's set way too rich for your 5000 ft altitude. Get on the Edelbrock site and find the chart for the 600. It'll tell you what jets and metering rods to use. I swapped mine out and the cold/wet weather stumble/bog went away. Mileage went up too. These carbs are set for sea level in the box as they want to err on the rich side I guess.
Model A Vette, you may have a point on checkin that rod - accel pump connection. I was "pretty sure" I put it all back the right way. (took some shots with the digital camera and was somewhat nervous during the re-assembly ...so I took a looooooooooong time.) But I'll look at that connection a bit more. Smokin Joe, the Edelbrock 600 was intially set up by a nearby shop about 10 years ago, and then re-tuned by a engine shop when I got the 350 rebuilt about 5 years ago...So I'm thinkin the jets and metering rods SHOULD be fine for this altitude. I'm more prone to think my HEI is the new problem (small as it is currently)..... Here's a bit more detail on the boggin. Before any hesitation , I noticed tonight that the idle would suddenly go down to ....well... no tach hooked up right now so, I'll just say it's that not quite right / v8 sounds sorta like a v6 sound. Kinda hobblin along...if that makes any sense The RPM'S are definitely a bit too low. And then I get hesitation / near death..So feeling a bit fed up with this, I pulled over to a well lit gas station and turned up the idle about a full turn and that seemed to help the rest of the way home....maybe that was all it was. A little confusing since the idle setting seemed a bit high before the rebuild.... Sometimes between the pause and my attempt to kick it back in, I get a nice "hickup" sounding backfire. I'm seriously thinkin it's my coil now, because when I bought the HEI dizzy and coil I was pretty thin on funds and had to go w/ a $12 coil w/ aluminum terminals (something to get by on I guess) Well, the first really cold night we had in early November (shortly after I got the HEI) I would get this same crap in the evenings after work. I figured it was just too cold , so I'd pull over wait about 5 mintues and then performance was fine. .........I just did my taxes and I'm gettin some money back (thank God!) so I may just get a decent cap (w/ BRASS terminals) and higher output coil. I've never really known what kind of power that cheapo coil is actually putting out anyway....
Sounds by what you describe that it is running on 1/2 a carb. I've had 2 edelbrocks and 1 holley the edelbrocks were great carbs for the first five or so years. I rebuilt both at about that time and experienced the same type of problems you are describing a year or so after every rebuild.I 100% swear by autozones rebuilt quadrajets (pre 77 only!!!) I finally got pissed at my 81 4x4 chevy and took the advice of a friend and called the Zone $123 later I have the best damn carb I have ever owned (except a race demon) it has improved my fuel mileage by 3 to 4 gallons and starts soo easy and idles without any caressing (keep in mind this is a nasty western NY winter with no choke!!! it fires and idles with no problem) I chased what I thought were ignition problems for a month before I finally brocke down and spent the $$$ I'm sold on these carbs for any daily driver.
Okay - here's something to check. After dark, fire the car up and open the hood...I want you to then turn off all the lights anywhere near the car. No headlights, no flashlights, no garage lights. You and your car alone in the dark with the hood up. Now, look underhood and follow the path of your spark plugs. Look for any stray blue sparks that may be "leaking" from your plug wires. If you see a light show, it's time for new plug wires. I recently did this little test on my '67 Wagon and was shocked at how bad it was. I replaced the crummy cheapo wires with a fresh set of MSD cables (the universal V-8 cut-to-fit kits is cheap and you can fit each wire perfectly where you'd like it to run. The routing can be done for the best-possible clearance to everything, and the universal kit is cheaper than the pre-fabricated kits). I can almost guarantee you've got a couple bad wires. Check it out and let me know what you find. Good luck Amigo! Scotch!~
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