Well i checked the spark, it aint a blue spark ! Kinda like my weed wacker Ya thinkin condenser ? Its ancient, but never used. Do they puke from sitting for years ? It was in an original delco box unopened.
They sure can. I've an old Eico capacitor bridge that will test them for what's called "insulation resistance". Basically about 500 volts DC. A DVOM can't do this. I've bought NOS that were complete duds. Depends on storage condition maybe. I'm not gonna guarantee this is the problem, but it sorta sounds like it from a distance. Bad spark is No Bueno.
Well thats my plan tomorrow morning, change out condenser and hope for the best. Going for a putt tomorrow with a few friends and our cars hopefully all goes well. I’ll keep ya posted
Leave the can connected to ported vacuum... hooking it up to manifold vacuum always messed up the idle on every engine I've ever tried it on.
Sounds to me like the diaphragm in your vacuum advance has a hole in it, giving you a vacuum leak. Had this happen to me a few years ago and drove me crazy. A new vacuum advance unit solved the problem. Good luck!
Sure. With the right springs and weights, you can get it in to just above idle if you want. Light springs, leave one spring off (!), heavy weights, reground weights to push harder on the cam...lots of ways to go, if you experiment long enough. Mike
That's kind of what I thought too. He says it's OK though, diaphragm holding vacuum, and advancing like it should. If so, the question is "how much", and it doesn't sound excessive. It simply shouldn't run rough at idle though, even with 20 or 30 degrees advance, connected at the manifold. Whether it's worth the trouble is another question. If anything it should run a little smoother.
I agree but there's no technical reason why it shouldn't run just fine if he wants to run the distributor at the manifold. Whatever the defect is, will most likely bugger something else up along the way.
Lots of good reading here. My plan is change condenser 1st If that dont work then I’ll put the vac can from the old distributor on. It only pulls 8* and it worked ok before i changed distributor. I changed distributor cos the old one was stuck and timing was set a 4. Ran like a pig. Had another distributor set up to go thinking the stuck one would break 20 years sitting aint good !
Well turned out to be bad condenser. Put another one in and idles great on manifold vacuum. Going for a putt out on some country roads hopefully the problem is solved.
I thought it might. That comes out to be $116.43 w/tax; +shop supplies and environmental fees of $9.57 so $126 on the nose. How would you like to pay today?
Well we got about 80 miles in before the clouds rolled in. Car ran well Even noticed a gain in mpg. After the car got hot it didn’t idle as good as it was at first. Might be running a little lean ? Dont know but im happy it doesnt stall at red lites any more.
What kind of carb problem ya thinkin ? If i go 1 step richer in cruise mode the car runs really good. But the gas gauge falls really good too. Edelbrock 1406 All jets,rods,springs are stock
If it idles cold better than it does when hot, that might point to it running a little on the rich side, not lean. It's better to be thorough, get in the manual for the carb and study it, make sure everything is adjusted and setup correctly. Measure, don't guess. If the spec is say, 3-4psi fuel pump pressure (whatever it may be) make sure it's right in there. Then set the float wherever it needs to be so the fuel level in the bowl is at the spec height. The factory calibrated everything, whether jets or metering rods, high speed air bleeds and gee-gaw innards etc around the fuel height. Holley did pretty good with their adjustable on-the-fly float setting and weep hole. A lot of carbs it isn't as convenient. One thing I see a lot of people do is mistake a rough ballpark bench setting instruction like float height for the final fine tune adjustments. You ain't done yet. The bench settings just get you close enough to run, every engine is slightly different so once a carb is actually on the engine and running it needs things trimmed out. A carburetor can be way off the beam and it won't seem to run too bad, but it will foul out plugs and waste gas with no performance.
Your right. I did spend a lot of time rebuilding the carb. Cleaning was the hard part. I was very meticulous with float settings etc. Engineers that are more smorter than me designed that stuff to work very well. The only thing i didnt do is check fuel pressure. Not sure the fuel pump brand but it is rated a 5psi. Do i need to put a tee in the fuel line for a gauge or can i disconnect fuel line and attach to gauge and read pressure while cranking
There enough fuel in the carb to idle long enough to get a pressure reading , but a T might be more accurate....
Yeah I’m sure a tee is the better choice. i dont have a lot of room to add anything permanently but I’ll figure something out.
Depends how they measured it wouldn't it? In the shop manual for my truck it says "FUEL PUMP STATIC PRESSURE 3.5 - 5.5 psi @ 500 RPM" the important thing is to measure it, lots of defective replacement fuel pumps these days and some of them are way off the beam. Somebody on the HAMB says they had one hitting 18 psi. Just install your vacuum gauge at the pump outlet and make sure it will play nice with your carb.
Well as luck would have it I’m at 7psi. But if ya look down carb at idle theres no indication of overflow or gas slobbering out of the venturi. Hate to put a regulator on, i need to find a place to hide it cos i hate cluttered up engine compartments. Although i did remove a pump that was putting out 11 psi, didnt really have issues but it was buggin me knowing it was that high.
OK, but have you looked down the carb at 65 mph, or at full throttle when passing on the highway at 80? Tough to do that. Excessive pressure will also chew up the fuel inlet needle quickly. What is the fuel pressure spec for the carb? That's what you want. If the pump is defective send it back. Another way of looking at it, fuel pumps provide flow not pressure, pressure is just resistance to flow. All you're trying to do is ensure that the fuel level in the carb stays consistent at all times under all conditions, from idle to wide open throttle.
I had a pressure regulator mounted right by the SBC fuel pump. It had several output openings. One for carb, one for pressure gauge. Plug the other. I also ran with no gauge. Once regulator is set, I saw no need for a gauge. In fact I adjusted my regulator between advertised minimum and maximum pressure about where I thought the afb should be set. Never did buy a gauge. It did help to have regulator. Phil
It sticks in my craw though, to have to spend more money and add another gee-gaw buying a pressure regulator, simply to dial down what amounts to nothing more than a defective fuel pump. There are specs for this stuff, if they can't meet it, send the damn thing back. I don't mind spending money, except when it's broke ass POS stuff right out of the box. Starts to add up after while.
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