A
Anonymous
Guest
63DropTop":12cy8503 said:
OK, enough goofing around in my thread! I need answers.
thanks gang!
A
Anonymous
Guest
the smoke could be excess liguids form being 180 out.
I have a slight tapping a lot too...I think i can minimize it if I play with the dizzy...
I was once told that a perfectly tuned straight 6 WILL have a slight ping no matter what...
who knows?
I have a slight tapping a lot too...I think i can minimize it if I play with the dizzy...
I was once told that a perfectly tuned straight 6 WILL have a slight ping no matter what...
who knows?
A
Anonymous
Guest
It's probably crankcase vapor/oil mist coming out. Do you have a PCV valve hooked up? The earlier cars (Pre '65?) didn't have a PCV valve, they had the 'road draft tube' which just let the vapor go straight out into the atmosphere. Having a PCV is a good thing, it gets rid of the crankcase pressure (remember if you have 200ci above the pistons, you have 200ci below the pistons as well).. not having some way to relieve the pressure can cause oil leaks as well. On some race motors they even do this one better by using a modified 'smog' pump to pull a vacuum on the crankcase to relieve the pressure.
Any 'perfectly' tuned motor shouldn't have any ping. You mention 'tapping' as well as 'pinging', are they the same noise happening to you? I usually take 'tapping' as valvetrain noise (worn lifters, rockers out of adjustment, even pretty worn valve guides) even possibly very worn rod bearings... I've even heard a very loose timing chain cause a 'tapping' or a bad fuel pump. I think of 'pinging' as 'knocking' as in the fuel mixture is being lit prematurely (either by timing being too advanced, spark plug heat range too hot, or something is hot in the combustion chamber and causing the mix to light before the spark plug does... such as a piece of carbon), too lean of a fuel mixture can cause this as well.
Also if you run a lower grade of gas than what you need for your engine, such as if you have a 10:1 motor, and you're running 87 oct gas... you can bet it's going to 'ping' or 'knock'
A
Anonymous
Guest
(meant to put this in the other post as well)
The port on the base of the carb is 'manifold' vaccuum or 'full' vacuum. The one on the side of the carb is 'ported' vacuum. You're right about the large one on the back, that's for PCV or a brake booster, if you don't have a PCV hooked up, this is where you should hook it up to (correct?).
The 'ported' source should'nt have any vacuum at idle, since it does you may have your idle speed screw out pretty far, which 'uncovers' the port above the throttle blades and causes this port to have vacuum.
As to which one to hook it up to... someone else may be able to recommend that... I'm pretty sure in stock apps they were hooked to 'ported'.. that's how I've always run them... I got experimenting with my truck (Chebby 350)I had it hooked to ported, and it worked okay... but I hooked it up to manifold just to see and it did have a lot more low end... especially right off of idle... but it's a low compression motor (8.5:1) and is totally stock internally. In thoery the manifold makes more sense, as it would give you more advance at idle and part throttle, then it would go away under wide open throttle (WOT) where it would cause too much advance in addition to your centrifugal (mechanical) advance. Unless someone has a recommendation, I'd say try both and see which one feels better... remember when you hook it up to manifold it's going to advance the timing more at idle, and possible increase the idle so you may need to back your idle speed screw out a bit...
The port on the base of the carb is 'manifold' vaccuum or 'full' vacuum. The one on the side of the carb is 'ported' vacuum. You're right about the large one on the back, that's for PCV or a brake booster, if you don't have a PCV hooked up, this is where you should hook it up to (correct?).
The 'ported' source should'nt have any vacuum at idle, since it does you may have your idle speed screw out pretty far, which 'uncovers' the port above the throttle blades and causes this port to have vacuum.
As to which one to hook it up to... someone else may be able to recommend that... I'm pretty sure in stock apps they were hooked to 'ported'.. that's how I've always run them... I got experimenting with my truck (Chebby 350)I had it hooked to ported, and it worked okay... but I hooked it up to manifold just to see and it did have a lot more low end... especially right off of idle... but it's a low compression motor (8.5:1) and is totally stock internally. In thoery the manifold makes more sense, as it would give you more advance at idle and part throttle, then it would go away under wide open throttle (WOT) where it would cause too much advance in addition to your centrifugal (mechanical) advance. Unless someone has a recommendation, I'd say try both and see which one feels better... remember when you hook it up to manifold it's going to advance the timing more at idle, and possible increase the idle so you may need to back your idle speed screw out a bit...
A
Anonymous
Guest
first off, i manually set TDC by checking for the piston rise through the #1 plug hole and turning by hand...BUT how do I know if I was on the right stroke? If I was timing based on the wrong stroke, would the motor run but just run crappy, ping, hesitate, be hard to start, etc?
Are you supposed to set the timing, mixture, idle with the car in park (auto trans) or in gear and if in gear, whats the safest way to do that
I'm going to add a PCV into the valve cover breather...good idea?
how does this sound for a plan?
1. I'm going to hook up the vac gauge to the ported port and turn the idle screw back so that I get closer to 0 hg which is where it is supposed to be right?
2. I'm going to recheck my TDC marking...again...depending on your answer to the question at the top
3. remove the vac advance line and plug it (do I need to plug the vac canister itself or just the hose from the carb?) and reset the timing. What advance amount should I start with (or should I try tuning it by ear..and if so, what's the best method for doing so?)
4. I'm going to reattach the vac line (ported) and see how she acts.
5. depending on #4, I may try hooking the dizzie up to the manifold port at the base of the carb...a little more low end never hurts! In doing this however, my initial timing is going to jump a fair amount right? Should I STILL set the timing with the vac line disconnected?
Thanks again for all of the help!
Are you supposed to set the timing, mixture, idle with the car in park (auto trans) or in gear and if in gear, whats the safest way to do that
I'm going to add a PCV into the valve cover breather...good idea?
how does this sound for a plan?
1. I'm going to hook up the vac gauge to the ported port and turn the idle screw back so that I get closer to 0 hg which is where it is supposed to be right?
2. I'm going to recheck my TDC marking...again...depending on your answer to the question at the top
3. remove the vac advance line and plug it (do I need to plug the vac canister itself or just the hose from the carb?) and reset the timing. What advance amount should I start with (or should I try tuning it by ear..and if so, what's the best method for doing so?)
4. I'm going to reattach the vac line (ported) and see how she acts.
5. depending on #4, I may try hooking the dizzie up to the manifold port at the base of the carb...a little more low end never hurts! In doing this however, my initial timing is going to jump a fair amount right? Should I STILL set the timing with the vac line disconnected?
Thanks again for all of the help!
A
Anonymous
Guest
sounds like a plan...I GUESS its correct LOL
I am gonna have to get up there someimte to see this BEAST of a machine....
fire breathing machine!!!
I am gonna have to get up there someimte to see this BEAST of a machine....
fire breathing machine!!!
A
Anonymous
Guest
LOL! It's not throwing flames anymore! :roll: It is kinda backfiring/puffing through the carb when starting it up though. That is why I was wondering about the possibility of having the TDC set on the wrong stroke.
Pompano Beach Air Show is this weekend. Supposed tobe a huge car show sat and sun. We're entering on Sunday. Should be GORGEOUS weather. Come up and hang out.
Pompano Beach Air Show is this weekend. Supposed tobe a huge car show sat and sun. We're entering on Sunday. Should be GORGEOUS weather. Come up and hang out.
A
Anonymous
Guest
backfiring sounds like a vaccuum leak. that happened to me when I was off on timing, I blew the vaccum line off....
was bucking lick a bronco and didnt stop when I killed ignition.
I will let you know about sunday. sounds like fun
was bucking lick a bronco and didnt stop when I killed ignition.
I will let you know about sunday. sounds like fun
A
Anonymous
Guest
my backfiring (not really backfiring so much as coughing) only happens during startup and only occasionaly. I'm wondering if besides the possibility of timing issues, having the old, small exhaust tied into the headers is putting excessive amounts of backpressure on it and causing this. I don't think it was happening before I tied the headers into the old system.
A
Anonymous
Guest
is your catatlitic converter clogged?
A
Anonymous
Guest
CATALYTIC CONVERTER??! now THAT is funny. You're kidding right?
motor -> 2" OUT headers -> dual 1 3/4" old mufflers -> 2 tailpipes
i tied the headers into the existing exhaust that the PO had put in (single stock manifold slipt out to two mufflers and talipipes)
now THAT is funny. You're kidding right?motor -> 2" OUT headers -> dual 1 3/4" old mufflers -> 2 tailpipes
i tied the headers into the existing exhaust that the PO had put in (single stock manifold slipt out to two mufflers and talipipes)
A
Anonymous
Guest
i was kidding, but is there a possiblity that something crawled into your tailpipe?
still sounds like a vaccuum issue...I am guessing now
heres another joke...did you take your parking brake off?
still sounds like a vaccuum issue...I am guessing now
heres another joke...did you take your parking brake off?
A
Anonymous
Guest
i just realized i haven't adjusted the float level in the carb! I knew I forgot something!
I knew I forgot something!
A
Anonymous
Guest
git er done....
that would do it wouldnt it....
that would do it wouldnt it....
A
Anonymous
Guest
I am assuming you were running a full exhaust before and did not have open headers. Assuming you just replaced a stock exhaust manifold with a set of headers......The headers should not create any back pressure. Even if the primary tubes were as small as 1" ID, those six tubes would flow nearly as much as if you had a 2.5" ID header pipe. The point bing that your tubes are likely quite a bit bigger than 1" and your stock exhaust was smaller than 2.5".
I had a motorcycle that would cough thru the carb when I had an o-ring leak on the intake manifold.
Doug
I had a motorcycle that would cough thru the carb when I had an o-ring leak on the intake manifold.
Doug
A
Anonymous
Guest
I think some of this info may have already been taken care of in some of your other posts.. but here goes my additional $.02...
TDC comes up twice, one time is at the end of the compression stroke when the spark plug is going to fire (the one you want)... and the other is on the end of the exhaust stroke and the exhaust valve is open... so when the piston is coming up on the compression stroke if you have the spark plug removed you should be able to feel some air coming out of the spark plug hole... on the exhaust stroke you won't feel much since the exh valve is open.. If your timing was set based on TDC on the wrong stroke (exhaust) I don't think it would even run at all... if it did it would probably run like total crap...
Ideally you should set everything with it in gear in an auto trans (since it will be under a slight load when in gear, and this drops the rpm a bit). Best way is to set your parking brake real tight (assuming that it works) and block the wheels with some pieces of scrap 4x4 wood, or sometime else the tires wouldn't be able to roll over very easily. Remember not to rev it while it's in gear, sounds dumb.. but after screwing with it for a little bit it may be easy to forget (done that )
I would add a PCV valve, as was mentioned before..
As for the 'plan'...
1) A good rule of thumb is to get your ignition (dwell if not running electronic ign, and timing) right on, then mess with your carb. If you plan with the carb first you may be covering up an ign prob (such as incorrect timing). I wouldn't worry about trying to get the ported vacuum to read '0', by getting your timing and everything else set, you'll probably need to back out your idle screw and that will fix that problem anyhow...
2) Double check the TDC mark using the method above... Do you have a new balancer? It's pretty common for older ones to 'slip' and make the timing marks or mark no longer accurate.. I also believe there's different balancer/pointer combos... correct? So be sure both of yours are 'matched'
3) You just need to plug the hose, reason being is that if the hose has vacuum and is not connected it will make a vacuum 'leak' and possibly change the idle a bit. The reason from disconnecting the hose from tha vac adv is so it's not adding any more 'advance' while you're trying to set your 'initial' timing. I would say a good starting point is 10-12 BTDC, depending on your cam you may need more (suggestions, anyone?).
I also saw that you said you didn't set your float level yet, set it after getting your timing, or if it's running very poorly do it first then do your timing (that's the only time I'd say ignore the ign first/carb second rule). I believe the carb float question was already answered.. but... remember the screw on the float adjustment is for locking the nut down, the nut is actually what raises and lowers your float level... turning the nut counter-clockwise will raise the level, clockwise will lower it... if you need to lower it remember it will not go down until the excess fuel in the bowl is used up... you can rev the motor a bit to take care of this.... raising the level will be practially instant... do it slowly and don't loosen the screw too much... just enough to turn the nut, move the nut a little, then tighten the screw and watch the level (I say to re-tighten the screw so it's not spraying/leaking fuel all over the place in the meantime).. I hope this comes off being fairly clear....
4 & 5) I'd worry about 4 and 5 after you already have the timing/float/idle mix and idle speed issues sorted out... since nobody jumped in about what source to took it to.. I'd start with ported vacuum to make it easier... if everything works okay, then I'd try the manifold source.
And always set your 'initial' timing with the vac adv disconnected...
Hope this helps.. (long winded as always)
TDC comes up twice, one time is at the end of the compression stroke when the spark plug is going to fire (the one you want)... and the other is on the end of the exhaust stroke and the exhaust valve is open... so when the piston is coming up on the compression stroke if you have the spark plug removed you should be able to feel some air coming out of the spark plug hole... on the exhaust stroke you won't feel much since the exh valve is open.. If your timing was set based on TDC on the wrong stroke (exhaust) I don't think it would even run at all... if it did it would probably run like total crap...
Ideally you should set everything with it in gear in an auto trans (since it will be under a slight load when in gear, and this drops the rpm a bit). Best way is to set your parking brake real tight (assuming that it works) and block the wheels with some pieces of scrap 4x4 wood, or sometime else the tires wouldn't be able to roll over very easily. Remember not to rev it while it's in gear, sounds dumb.. but after screwing with it for a little bit it may be easy to forget (done that
)I would add a PCV valve, as was mentioned before..
As for the 'plan'...
1) A good rule of thumb is to get your ignition (dwell if not running electronic ign, and timing) right on, then mess with your carb. If you plan with the carb first you may be covering up an ign prob (such as incorrect timing). I wouldn't worry about trying to get the ported vacuum to read '0', by getting your timing and everything else set, you'll probably need to back out your idle screw and that will fix that problem anyhow...
2) Double check the TDC mark using the method above... Do you have a new balancer? It's pretty common for older ones to 'slip' and make the timing marks or mark no longer accurate.. I also believe there's different balancer/pointer combos... correct? So be sure both of yours are 'matched'
3) You just need to plug the hose, reason being is that if the hose has vacuum and is not connected it will make a vacuum 'leak' and possibly change the idle a bit. The reason from disconnecting the hose from tha vac adv is so it's not adding any more 'advance' while you're trying to set your 'initial' timing. I would say a good starting point is 10-12 BTDC, depending on your cam you may need more (suggestions, anyone?).
I also saw that you said you didn't set your float level yet, set it after getting your timing, or if it's running very poorly do it first then do your timing (that's the only time I'd say ignore the ign first/carb second rule). I believe the carb float question was already answered.. but... remember the screw on the float adjustment is for locking the nut down, the nut is actually what raises and lowers your float level... turning the nut counter-clockwise will raise the level, clockwise will lower it... if you need to lower it remember it will not go down until the excess fuel in the bowl is used up... you can rev the motor a bit to take care of this.... raising the level will be practially instant... do it slowly and don't loosen the screw too much... just enough to turn the nut, move the nut a little, then tighten the screw and watch the level (I say to re-tighten the screw so it's not spraying/leaking fuel all over the place in the meantime).. I hope this comes off being fairly clear....
4 & 5) I'd worry about 4 and 5 after you already have the timing/float/idle mix and idle speed issues sorted out... since nobody jumped in about what source to took it to.. I'd start with ported vacuum to make it easier... if everything works okay, then I'd try the manifold source.
And always set your 'initial' timing with the vac adv disconnected...
Hope this helps.. (long winded as always)
A
Anonymous
Guest
Oh, and I don't think your backfiring is caused by your headers being connected into your old exhaust.... especially since you said you had dual pipes... An excessively lean mixture could cause backfiring as well.. which could be tied to your float level if it is too low... If you rev it, then it pops through the carb, then your accelerator pump circuit is not rich enough... which can be changed be using larger 'squirters' or changing the pump cam, or it's position...
