318 stalls in Drive

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Pull the carb off,empty it, flip it over, using the speed screw adjust the transfer port exposure to a little taller than wide. Reset the mixture screws to 2.5turns out.Next; prove you got the right base gasket, prove the manifold mounting flange is not cracked, and prove you can marry those two without a base vacuum leak. Then,flip the carb right side up, bolt it back on,and check/adjust the fuel level to the factory setting.If the manifold has EGR provision, make sure it has been defeated.Finally,fill the carb up thru the bowl vent with about 50cc gas.
Next;defeat the vacuum advance for now and make sure the PCV is hooked up properly, After this, do not touch the speed screw;instead,adjust the idle speed with timing and idle air bypass. 18* initial is about right. Maybe a little less.
Now;Start her up!
The very first thing you gotta do is make sure the power-valve system is not activated. That carb came off an engine that was probably pulling more than 18 inches of vacuum so it will have a pretty strong spring activating the PV or metering rod's power-piston. Your 284/484 is gonna be down around 10" or less, so as far as the PV system is concerned, the engine is working pretty hard and the PV could be a good ways open. If it is,then it's gonna be your job to re-calibrate it and make sure it stays closed at idle. And don't be clipping coils off the spring;that will really mess things up. Go find a similar spring with less pressure and clip coils off that one until it is the same length,then recheck it's calibration. Or just for testing purposes, pull the spring out of service, until later.
OK so once the PV stays off/closed at idle,then;
If the idle speed is faster than 750/800, even with the initial timing retarded to as little as 14*, then go look for a vacuum leak including sucking from the crankcase. Find it and fix it. If the vehicle has a brake booster,prove it's not leaking or defeat it for now.
But if,as I suspect, the idle speed will be lower than 750/800,then you will have to provide additional air around or thru the throttle valves; do not use the speed screw. You can figure out how much more air to give her,by introducing a calibrated leak into the PCV system. I just drill a hole in the top of the plastic PCV. Once you have her up to 700,then fiddle with the Mixture screws for best quality idle. Then figure out how far out they are,.You want them to be about 2 to 3 turns out. If they are less than 2, then close the throttle with the speed screw up to 1/2 turn and reset the mixture screws. But if the mixture screw are out more than 3 turns then open the throttle with the speed screw up to .5 turn, and reset the mixture screws,back to 2.5
Now, try putting her into gear and see what happens. The idle speed should not drop more than about 100/150 rpm. If it does, check the idle timing. If it is less than 18* add 2 degrees and try it again. If it still drops too far, add 1/2 turn to the mixture screws, and try again. If it still drops too far add 2 more degrees timing. If it still drops too far, then, STOP. Open the throttle 1/2 turn on the speed screw, and return the mixture screws to 2.5 turns. If the timing is more than 18* put it back to 18*. Now check the idle speed. By now it might be over 750. If it is between 750 and 850, put it in gear and check the Rpm-drop. If it is more than 100 but less than 150, and the idle quality is good, then you are done.
Now we have to make permanent the idle air bypass that you introduced to the PCV system. Simply measure the size of the hole, and calculate the area, divide it by two, back calculate the size of the hole to make this new 1/2area, and that is the size of the two new holes you are gonna drill in the butterflys, one in each.If you have a choice between two hole sizes, then opt for the smaller of the two. Put each hole on the front half of the butterfly,about half way between the idle discharge ports and the transfer slots, AND at least 1/4" away from the edge.The exact position is not critical,so long as it's not under one of the discharges. Chamfer the holes, both sides of the valves, when you are done. Yeah you have to take the carb off and drill from the underside. Don't forget to plug the test hole in the PCV valve.
Now you can restore the booster into operation, but it's still too early to reconnect the Vcan
Now it's time to;
A) limit the power-timing
B) install a preliminary curve
C) if you removed the power-piston spring, reinstall it and calibrate the PV power piston as to it's rate and timing.
D) reconnect the Vcan and calibrate it.
 
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AJ/FormS said:
Pull the carb off,empty it, flip it over, using the speed screw adjust the transfer port exposure to a little taller than wide. Reset the mixture screws to 2.5turns out. Flip it right side up, and bolt it back on.But before you do, prove you got the right base gasket, prove the mounting flange is not cracked, and prove you can marry those two without a base vacuum leak. Defeat the vacuum advance for now. Make sure the PCV is hooked up properly.Fill the carb up thru the bowl vent with about 50cc gas. After this, do not touch the speed screw; Adjust the idle speed with timing and idle air bypass. 18* initial is about right. Maybe a little less.
Start her up.
OK now, the idle target is 750 to 800 with that super low stall TC.
The very first thing you gotta do is make sure the power-valve system is not activated. That carb came off an engine that was probably pulling more than 18 inches of vacuum so it will have a pretty strong spring activating the PV or metering rod's power-piston. Your 284/484 is gonna be down around 10 or less, so as far as the carb is concerned, the engine is working pretty hard and the PV will be a good ways open. It's gonna be your job to re-calibrate it and make sure it stays closed at idle. And don't be clipping coils off the spring;that will really mess things up. Go find a similar spring with less pressure and clip coils off that one until it is the same length,then recheck it's calibration.
OK so once the PV stays off,then;check/adjust the fuel level to the factory setting.
Then,if the idle speed is faster than 750/800, even with the initial timing retarded to as little as 14*, then go look for a vacuum leak including sucking from the crankcase. Find it and fix it. If the manifold has EGR provision, make sure it has been defeated.If the vehicle has a brake booster,prove it's not leaking or defeat it for now.
But I suspect the idle speed will be lower than 750/800. If it is, you will have to provide additional air around or thru the throttle valves; do not use the speed screw. You can figure out how much more air to give her,by introducing a calibrated leak into the PCV system. I just drill a hole in the top of the plastic PCV. Once you have her up to 700,then fiddle with the Mixture screws for best quality idle. Then figure out how far out they are, You want them to be about 2 to 3 turns out. If they are less than this, then close the throttle with the speed screw up to 1/2 turn and reset the mixture screws. But if the mixture screw are out more than 2.5 turns then open the throttle with the speed screw up to .5 turn, and reset the mixture screws,back to 2.5
Now, try putting her into gear and see what happens. The idle speed should not drop more than about 100 rpm. If it does, check the idle timing. If it is less than 18* add 2 degrees and try it again. If it still drops more than 100, add 1/2 turn to the mixture screws, and try again. If it still drops more than 100 add 2 more degrees timing. If it still drops more than 100, STOP. Open the throttle 1/2 turn on the speed screw, and return the mixture screws to 2.5 turns. If the timing is more than 18* put it back to 18*. Now check the idle speed. By now it might be over 750. If it is between 750 and 850, put it in gear and check the Rpm-drop. If it is more than 100 but less than 150, and the idle quality is good, then you are done.
Now we have to make permanent the idle air bypass that you introduced to the PCV system. Simply measure the size of the hole, and calculate the area, divide it by two, back calculate the size of the hole to make this new 1/2area, and that is the size of the two new holes you are gonna drill in the butterflys, one in each. Put each hole on the front half of the butterfly,about half way between the idle discharge ports and the transfer slots, AND at least 1/4" away from the edge.The exact position is not critical,so long as it's not under one of the discharges. Chamfer the holes when you are done. Yeah you have to take the carb off and drill from the underside. Don't forget to plug the test hole in the PCV valve.
Now you can restore the booster into operation, but it's still too early to reconnect the Vcan
Now it's time to;
A) limit the power-timing
B) install a preliminary curve
C) calibrate the PV power piston as to it's rate and timing.
D) reconnect the Vcan and calibrate it.

Editing now
Click to expand...
You know I was going to say that but you beat me to it again!
 
j par said:
Yeah it's West Coast and we're still washing Mash here. And just so you know the cam is a manifold water pump and timing chain cover pull not a motor pull. You may have to pull some of the grill apart to get the cam to slide all the way out. And the converter is a transmission pull both of which should be take apart one day and put together the next. Unbolt and bolt back in. Not rocket science just a lot of dirt and Grease if you don't have your stuff clean.
Good night and I'll check out your response when I wake up in the morning LOL
Click to expand...

*Pulling the transmission alone requires putting the truck on jackstands and laying on my back to unbolt the trans. ,crossmember, blocking up the engine. Realigning the trans. while laying on my back underneath is not fun. On a dodge truck, the radiator core support unbolts and this gives plenty of room and it's much easier to pull the engine/trans combo out the front. I usually pick up the engine/trans a couple inches and roll the truck backwards away from the cherry picker.
*As for an in frame camshaft replacement on a truck, it's very easy. Like mentioned before, unbolt and remove the core support and I can sit on the front bumper and tend to the water pump/chain, etc.
*But, woudn't it be bad form to just swap the cam and not replace the cam bearings? Approx. 34k miles on the '84 engine.
 
65Val said:
How quick does the mechanical advance in the distributor come in? If it's already advancing @ 850 rpm, then when it goes into gear, as the rpm drops back to 550, timing drops back as well because the convertor is too low stall speed, and added together with a way-to-big cam for the convertor, causes the engine to stall. Simple huh?
Click to expand...
Excellent point. Somewhere I have a chart that shows the advance curve for that distributor. Somewhere. I wonder if I could just tie the flyweights down so they don't move and check the timing? Or just have someone put the truck in Drive while watching a timing light?
 
AJ/FormS said:
Pull the carb off,empty it, flip it over, using the speed screw adjust the transfer port exposure to a little taller than wide. Reset the mixture screws to 2.5turns out.Next; prove you got the right base gasket, prove the manifold mounting flange is not cracked, and prove you can marry those two without a base vacuum leak. Then,flip the carb right side up, bolt it back on,and check/adjust the fuel level to the factory setting.If the manifold has EGR provision, make sure it has been defeated.Finally,fill the carb up thru the bowl vent with about 50cc gas.
Next;defeat the vacuum advance for now and make sure the PCV is hooked up properly, After this, do not touch the speed screw;instead,adjust the idle speed with timing and idle air bypass. 18* initial is about right. Maybe a little less.
Now;Start her up!
The very first thing you gotta do is make sure the power-valve system is not activated. That carb came off an engine that was probably pulling more than 18 inches of vacuum so it will have a pretty strong spring activating the PV or metering rod's power-piston. Your 284/484 is gonna be down around 10" or less, so as far as the PV system is concerned, the engine is working pretty hard and the PV could be a good ways open. If it is,then it's gonna be your job to re-calibrate it and make sure it stays closed at idle. And don't be clipping coils off the spring;that will really mess things up. Go find a similar spring with less pressure and clip coils off that one until it is the same length,then recheck it's calibration. Or just for testing purposes, pull the spring out of service, until later.
OK so once the PV stays off/closed at idle,then;
If the idle speed is faster than 750/800, even with the initial timing retarded to as little as 14*, then go look for a vacuum leak including sucking from the crankcase. Find it and fix it. If the vehicle has a brake booster,prove it's not leaking or defeat it for now.
But if,as I suspect, the idle speed will be lower than 750/800,then you will have to provide additional air around or thru the throttle valves; do not use the speed screw. You can figure out how much more air to give her,by introducing a calibrated leak into the PCV system. I just drill a hole in the top of the plastic PCV. Once you have her up to 700,then fiddle with the Mixture screws for best quality idle. Then figure out how far out they are,.You want them to be about 2 to 3 turns out. If they are less than 2, then close the throttle with the speed screw up to 1/2 turn and reset the mixture screws. But if the mixture screw are out more than 3 turns then open the throttle with the speed screw up to .5 turn, and reset the mixture screws,back to 2.5
Now, try putting her into gear and see what happens. The idle speed should not drop more than about 100/150 rpm. If it does, check the idle timing. If it is less than 18* add 2 degrees and try it again. If it still drops too far, add 1/2 turn to the mixture screws, and try again. If it still drops too far add 2 more degrees timing. If it still drops too far, then, STOP. Open the throttle 1/2 turn on the speed screw, and return the mixture screws to 2.5 turns. If the timing is more than 18* put it back to 18*. Now check the idle speed. By now it might be over 750. If it is between 750 and 850, put it in gear and check the Rpm-drop. If it is more than 100 but less than 150, and the idle quality is good, then you are done.
Now we have to make permanent the idle air bypass that you introduced to the PCV system. Simply measure the size of the hole, and calculate the area, divide it by two, back calculate the size of the hole to make this new 1/2area, and that is the size of the two new holes you are gonna drill in the butterflys, one in each.If you have a choice between two hole sizes, then opt for the smaller of the two. Put each hole on the front half of the butterfly,about half way between the idle discharge ports and the transfer slots, AND at least 1/4" away from the edge.The exact position is not critical,so long as it's not under one of the discharges. Chamfer the holes, both sides of the valves, when you are done. Yeah you have to take the carb off and drill from the underside. Don't forget to plug the test hole in the PCV valve.
Now you can restore the booster into operation, but it's still too early to reconnect the Vcan
Now it's time to;
A) limit the power-timing
B) install a preliminary curve
C) if you removed the power-piston spring, reinstall it and calibrate the PV power piston as to it's rate and timing.
D) reconnect the Vcan and calibrate it.
Click to expand...
AJ, thank you so much for taking the time to post all that. I have done what you said. Until I got to this part: And don't be clipping coils off the spring;that will really mess things up. Go find a similar spring with less pressure and clip coils off that one until it is the same length,then recheck it's calibration.
Finding suitable springs for a 2 bbl is difficult. I have the AFB spring re-cal. kit but those springs will not work in the 2bbl. I think I'll print what you wrote and take it out to the truck and 'tinker' a bit. Transfer slots were set to "square". I've turned the idle speed up 1/2 turn from that to keep the engine idling.
 
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iScamp said:
Excellent point. Somewhere I have a chart that shows the advance curve for that distributor. Somewhere. I wonder if I could just tie the flyweights down so they don't move and check the timing? Or just have someone put the truck in Drive while watching a timing light?
Click to expand...
Yes...either will give you some info. I would try the latter first. I still think your convertor is way tight for that cam, and the BBD is not suited for both of those without some modifications.
 
I would pull that cam in a heartbeat. Get an rv cam and lifter kit from Summit and a timing cover gasget kit and intake gasgets from local auto parts store for all around 150.00 a .484 purpleshaft in a stock 318 never works out right. Nowhere near the right compression for it to run correctly, plus a stock, low stall converter, 6,000# truck, 4wd... just wrong on all accounts. Change the cam and be done with it.
 
gliderider06 said:
I would pull that cam in a heartbeat. Get an rv cam and lifter kit from Summit and a timing cover gasget kit and intake gasgets from local auto parts store for all around 150.00 a .484 purpleshaft in a stock 318 never works out right. Nowhere near the right compression for it to run correctly, plus a stock, low stall converter, 6,000# truck, 4wd... just wrong on all accounts. Change the cam and be done with it.
Click to expand...

Would you replace the cam bearings?
 
iScamp said:
Would you replace the cam bearings?
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I wouldn't change the cam bearings. It's not worth it. My first 318 had tons of miles on it I just pulled that sucker out and push a new one and no big deal you're given it too much thought.
 
Nope. I have a 318 on the stand right now with 120,000 miles on it and cam bearings still look new.
 
j par said:
I wouldn't change the cam bearings. It's not worth it. My first 318 had tons of miles on it I just pulled that sucker out and push a new one and no big deal you're given it too much thought.
Click to expand...
Maybe so. Started so many projects thinking they were going to be simple and turned into a enduring struggle.
I"ll definitely give the cam swap more thought.
Thanks FABO guys.
 
iScamp said:
AJ, thank you so much for taking the time to post all that. I have done what you said. Until I got to this part: And don't be clipping coils off the spring;that will really mess things up. Go find a similar spring with less pressure and clip coils off that one until it is the same length,then recheck it's calibration.
Finding suitable springs for a 2 bbl is difficult. I have the AFB spring re-cal. kit but those springs will not work in the 2bbl. I think I'll print what you wrote and take it out to the truck and 'tinker' a bit. Transfer slots were set to "square". I've turned the idle speed up 1/2 turn from that to keep the engine idling.
Click to expand...
If you're only 1/2 turn up from square,and your timing is about 18*, and you have this problem, then something is mechanically wrong. First get a second witness to the rpm. Then I'll bet it's getting way too much idle-fuel. Pull a couple of plugs and see what's going on in there. While the plugs are out, do a compression test. If any are more than 15 psi lower than the average, then do a LeakDown test as well.If the leakdown test shows less than six or 8 psi,then check the cam-timing.Or at least check where split overlap is occurring, which is pretty easy to ball-park.
If you have metering rods, they HAVE to stay down at at idle, and probably up to about 1/2 throttle . If you have to, just pull the spring out.You can still drive to about 30/40mph using a very small amount of pedal.
If there are two consecutively firing cylinders sucking air at the intake ports..... like 5 and 7....., well that could cause a stalling
Another thing to do is get the rear wheels off the ground. With the engine running,and the trans in manual low, ride the brake pedal to slow the engine down to about 600/550.Let the rpm stabilize for a couple of seconds.The engine should be happily rumpidy rumping, and it should not take a lot of brake to get there.After 2 or 3 seconds,apply the brake to stop the rear wheels. If it stalls, throw that TC away.
 
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iScamp said:
Would you replace the cam bearings?
Click to expand...
If you replace the cam (which has my vote too), you can simply peer down through the valley with the intake off, and see the lower part of the cam bearings; use a mirror through the front and you can see the upper parts. If they have no chunks missing (or maybe just a small chunk here or there), and there is no deep scoring, then you can do it. Some older bearings DO show chunks missing.. it may be due to acids in the oils attacking the bearing surfaces.

FWIW: Back when I was young and poor, I raced with some pretty loose cam bearings.... in an engine that revved to 8k and ran hard for many minutes at a time (rallying).
 
iScamp said:
Maybe so. Started so many projects thinking they were going to be simple and turned into a enduring struggle.
I"ll definitely give the cam swap more thought.
Thanks FABO guys.
Click to expand...
Yes the enduring struggle! I love it! Smashing the gas pedal is the easy fun...
 
When I switched my cam, my cam bearings were really ugly in my first 318. Okay so they were ugly with the old Cam and now they're ugly with the new cam and off I went...
 
What's the worst could happen? You lose a $105 cam and lifters from Summit in a 200,000 mile 318? Which by the way is not going to happen because it's not going to be as hot as the one you have in there!
 
I would look into the vacuum leak angle, and check float level, check Jets in carb, might not be able to get enough gas through to run under load
 
Also the magic number is 650 RPMs in drive adjust to this if it slams into gear and drive and reverse check your kickdown cable adjustment it will soften it
 
Well, it's been almost a year since this thread was active. I"m slow. I know.

Replace the cam, they said. It'll run fine, they said.

.
And of course , you guys were right. So actually it was late last summer when I got around to it. Bought a new camshaft / lifters. Made the swap in one day.
The camshaft is the OEM profile. It was cheaper that way.
Runs just like any stock truck. Idles nice. If I recall,17" hg vacuum at idle. Throttle response is great.

The only drawback is the exhaust note. With the old cam, the exhaust would cackle like a dragster. Much lower decibels of course. Now the exhaust note is a very mellow, low tone.

Thanks again, for all the help.
 
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