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Static Timing On De-Smogged California Car- Advance Past 6 Btdc?


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I've removed the reactor manifold (air pump, egr system, etc.) from my stock 1976 car.

Older, wiser people have told me that one can easily explode a muffler because at idle,

the mixture is no longer diluted with exhaust, there is no after-burn in the reactor and

the static timing is quite low, ie, 6 degrees or so.

 

Where should my static timing be to avoid problems?

 

I should probably disable the vacumn retard (I have the adv. and ret. distributor) and

hook up the vac. adv. to manifold vacumn, yes?

 

Many thanks!

 

 

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Disable vacuum retard and hook up vacuum advance, thats what my desmogged 76 is setup at.

 

Is the car running? Set timing at 1500rpm and check fuel mixture and be done. You're not going to blow up a muffler.

Er, uh, it was running just fine before I "fixed" it. Now, it won't stay lit under 2500 RPM or so.

But I did replace the points, wires, cap, rotor and coil, so I have many grey areas to think about.

Dwell was 51 when it would not idle, but it is now set at 61 but I have yet to muster the courage to

see what happens ;>) I should check the electric idle shutoff valve to be sure it stays open, kill the vac. ret

and so forth. Thanks!

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I have verified the dwell is at 61, the points begin to open very close to TDC and I have not moved the dizzy at all.

So, should I keep it running at 2000 rpm and then spray some starting fluid wherever an intake leak might occur?

Or safer to use a hefty cigar, piece of incense or one of those green bug sprialy thingies?

 

I should note the intake manifold is one that has been peanutted out for the weber carb, but I have the original

solex didta on there. Probably not a problem?

MY THANKS for your concern and help!

 

 

 

Are you sure that there aren't any intake leaks after removing everything? That and it's really best to set the timing dynamically to 28-34 deg at 2500rpm with vacuum disconnected.

Vacuum advance is usually connected to ported vacuum.... And yes check that the idle valve is still operating.

HTH

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Well, 2000rpm is a BIG vacuum leak, and should be obvious; something like not capping off the EGR or Air Injection stuff leading to the intake manifold. You should also hear a massive vacuum leak like this. We have a smoke machine (like model train smoke only much more and electric pump to fill the motor. Otherwise for smaller leaks I take a propane bottle with a nozzle on it (like a can of carb cleaner only safer). Following the smoke being sucked in from a lit cigar would work better for a small leak with the engine at idle.

 

The idle valve being bad will cause a very similar thing, won't run without holding the throttle open to hold the motor above 2K. Dies if you try and let it get anywhere near idle.

 

HTH

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Maybe I should have given some hints. No, think around the 1940's...it's pretty obscure...it was a 1941 Caddy

with a military motor in it - there were 2 big bearing in the manifold, apparently for use in tanks where they

would take power from somewhere, run a shaft thru the manifold to power something, maybe a turret?

 

 

 

Porsche 928.

 

Do I win?

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I was afraid (and hoping!) you'd say that. Because I don't think it is a leak. The idle valve has power to it, but I

better check for that little click that I used to hear when plugging and unplugging it. Keep your toes crossed,

and I really do appreciate your time!

 

 

Well, 2000rpm is a BIG vacuum leak, and should be obvious; something like not capping off the EGR or Air Injection stuff leading to the intake manifold. You should also hear a massive vacuum leak like this. We have a smoke machine (like model train smoke only much more and electric pump to fill the motor. Otherwise for smaller leaks I take a propane bottle with a nozzle on it (like a can of carb cleaner only safer). Following the smoke being sucked in from a lit cigar would work better for a small leak with the engine at idle.

 

The idle valve being bad will cause a very similar thing, won't run without holding the throttle open to hold the motor above 2K. Dies if you try and let it get anywhere near idle.

 

HTH

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The idle valve plunger -seemed- stuck, not 100% sure, but I ended up cutting off the

tip right at the threads.

 

Result: engine started with part throttle and instantly revved up past 3000, so I shut

it down. My guess is the plunger is not just an on/off deal, but meters fuel in some way.

 

I order one from BMW of S Atlanta, we shall see.

 

 

 

 

Well, 2000rpm is a BIG vacuum leak, and should be obvious; something like not capping off the EGR or Air Injection stuff leading to the intake manifold. You should also hear a massive vacuum leak like this. We have a smoke machine (like model train smoke only much more and electric pump to fill the motor. Otherwise for smaller leaks I take a propane bottle with a nozzle on it (like a can of carb cleaner only safer). Following the smoke being sucked in from a lit cigar would work better for a small leak with the engine at idle.

 

The idle valve being bad will cause a very similar thing, won't run without holding the throttle open to hold the motor above 2K. Dies if you try and let it get anywhere near idle.

 

HTH

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Um OK.... That's not how I would have recommended diagnosing it... Now you have to figure out how to get the idle jet and threaded part out. And may have ruined a perfectly good idle solenoid. BTW, is this a Weber carb or the stock Solex were talking about here. If its a Weber the solenoid from the dealer will not fit!

Here's how you should've done it... Unplug the idle valve with the key in the ignition on position. Tap the wire connector on the spade and listen for a clicking. If you definitely hear no clicking then use a volt meter to be sure you have 12v power at the wire. Turn the ignition back off for the next steps... If you did hear clicking then unscrew the solenoid and pull the idle jet out of it, take a magnifying glass and see if the jet is clogged... Blow, clean, use carb cleaner, a tiny piece of wire to unclog the jet. Just do not damage or make the holes any bigger. Take compressed air and blow out the passages in the carb. Warning! Fuel WILL spray out of the top of the carb. Put the jet back in the holder, but not quite all the way seated in the holder, and screw the idle solenoid back in and connect up. Start the car, if the problem still exists then either look deeper in the carb or take another diagnostic path.

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I should have mentioned I removed the valve first ;>)

I then looked with a magnifying glass to see if the plunger moved when activated.

Didn't seem to. Soaked the tip in liquid wrench, sprayed carb cleaner into the holes, etc.

 

The solenoid/plunger/tip don't come apart, do they?

Anywho, since I killed mine, serves me right to have to buy a new one.

Hope it was the culprit.

 

 

Um OK.... That's not how I would have recommended diagnosing it... Now you have to figure out how to get the idle jet and threaded part out. And may have ruined a perfectly good idle solenoid. BTW, is this a Weber carb or the stock Solex were talking about here. If its a Weber the solenoid from the dealer will not fit!

Here's how you should've done it... Unplug the idle valve with the key in the ignition on position. Tap the wire connector on the spade and listen for a clicking. If you definitely hear no clicking then use a volt meter to be sure you have 12v power at the wire. Turn the ignition back off for the next steps... If you did hear clicking then unscrew the solenoid and pull the idle jet out of it, take a magnifying glass and see if the jet is clogged... Blow, clean, use carb cleaner, a tiny piece of wire to unclog the jet. Just do not damage or make the holes any bigger. Take compressed air and blow out the passages in the carb. Warning! Fuel WILL spray out of the top of the carb. Put the jet back in the holder, but not quite all the way seated in the holder, and screw the idle solenoid back in and connect up. Start the car, if the problem still exists then either look deeper in the carb or take another diagnostic path.

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Well, the solenoid only has a single wire; power, meaning it grounds through the body of the carb. If you removed it and expected it to do something without grounding it to anything....

 

There's an idle jet that comes off the tip, it's a swage fit; then you can see the pin that pushes out to shut the fuel off when there's no power.

 

HTH

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