Mopar 383 help please

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JungleCrow

JungleCrow

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Hey, I was wondering if someone could be a miracle and help me with a couple things on my engine. I had just put a new distributor, intake manifold, plugs/wires and coil into my car. I did this because my car had a vacuum of around 5 (the needle wiggles fast around 5) The electrical stuff was just because. Now my car still has a vacuum of 5 (intake bolts are tight) but start, runs and revs. When I adjust the idle mixture screws I dont get any more vacuum and hardly get any less. The only thing I hear wrong with it from ear is that on the drivers side I hear a click click click. I checked around the manifold but everything looked clean and couldnt feel any crazy air leaks. It sounds like the noise is coming from the valves over either the 5 or 7 cylinder. Also sometimes I can hear a very slight rev in the engine rpm I thought maybe my very old carb has some fuel distribution problems but maybe its the loose push rod? (If that is what the noise actually is) Any ideas? Also, does anyone have a good webpage or information on tightening the pushrods/lifters? I did it on my K5 blazer years ago in HS but dont quite remember the sequences and steps.

So is my 5 vacuum bad if the engine runs well? Could the lifters be contributing to this?

intial timing is a little less than 10 degrees and my distributor has a limit of 24 factory. Also have a vacuum advance.
 
A low vacuum reading plus a quickly fluctuating needle usually indicates weak or broken valvesprings, or something amiss in the valvetrain.
 
Does anyone know what the stock spring specs are so I can replace them? Should I go ahead and replace lifters too?

Well the engine runs fine except for the noise.
 
Are you sure you are on a manifold vacuum port and not a ported vacuum?
Does it have power brakes? Possible leaking booster. Also check the hose going to it. Check the pcv valve and make sure it isn't stuck open. Check the pcv hose, I have seen them collapse and suck air.

Did this just happen all of a sudden?
It runs fine other wise?
At 5" of vacuum I would expect the car to die just trying to put it in gear.
At what rpm is it idling at?
Throttle may be opened to compensate for a vacuum leak, thus getting no response adjusting the mixture screws.
 
No, Im not sure. I put the gauge on the only vacuum port on the bottom of my carb.

It doesnt have power brakes. No pcv valve.

Its been like this and has not changed since I replaced the stuff. Only difference is now it starts, runs and even revs to high rpm.

Not sure what its idling at RPM wise cuz I dont have a tach but it sounds normal. However sometimes it gets stuck at a high rpm. Almost like the carb isnt coming off of fast idle once warm. Had that happen when I drove it. Also, it doesnt have the power a 383 should have. That noise I talked about gets annoying loud when I give it gas. Revs up but not a whole lot of power.

If your serious on helping me I can take a good quality video and post it up.
 
Do/check the easy stuff first.
That's why I suggested some of the things I did.
I would hate to see you tear down the engine, if it is something on the outside.
Only One vacuum port? Is there not one on the back side of the intake, and one on the carb or does it have a plug in it? Should have a 3/8" port for the pcv/booster hook up. is it capped off?
Does the vacuum reading increase when you slowly open the throttle?
Was the vacuum low before the intake change?
What intake did you put on?
What carburetor?
Double check the plugs and make sure they are tight and one isn't loose making the ticking sound.
 
Mopower71 said:
Do/check the easy stuff first.
That's why I suggested some of the things I did.
I would hate to see you tear down the engine, if it is something on the outside.
Only One vacuum port? Is there not one on the back side of the intake, and one on the carb or does it have a plug in it? Should have a 3/8" port for the pcv/booster hook up. is it capped off?
Does the vacuum reading increase when you slowly open the throttle?
Was the vacuum low before the intake change?
What intake did you put on?
What carburetor?
Double check the plugs and make sure they are tight and one isn't loose making the ticking sound.
Click to expand...

There are two 3/8 vacuum ports, one for the distributor and another one the same size on bottom (one I was using and fits my gauge). Intake has a plug. Vacuum reading steadily increases with rpm. Vacuum is acting the exact same even after intake change. I put on this intake. Old intake was the same just an edlebrock version. Carb is an older 670cfm Holley Street Avenger. Ill have to check the plugs tomorrow. I just put them on today so Ill have to double check if they are lose.
 
Ya, I can do the springs no prob but I really dont want to take the intake off again to change the lifters.
 
If it increases with throttle you have it hooked to a throotle plate sensitive port. Vaccum should be the most at idle. Thake the plug out of the intake and install a vaccum tree and hook your gauge there
 
JungleCrow said:
Ya, I can do the springs no prob but I really dont want to take the intake off again to change the lifters.
Click to expand...

On a BB the lifters can be replace thru the head, need to remove the rocker asemblies and use a special tool that grabs the lifters.
 
Quote: intial timing is a little less than 10 degrees and my distributor has a limit of 24 factory. Also have a vacuum advance.

Are you saying that the limit of 24 factory is the centifugal therefore giving you a total of 34 with the vacuum advance plugged off. First bump the initial timing up to 12 and you want the centri. to be fully in at around 2200 rpm. Hook your vacuum guage to the manifold like said above. What are the specs on the cam shaft and do you know what the comp ratio is also what tranny you running and if it's an auto what's the converter stall. The ticking could also be a exhaust manifold leak so make sure your bolts are all tight and does the ticking seem to go away when you rev the engine up. Almost forgot, do you have adjustable rockers on this engine or the stamped steel (stock) which aren't adjustable.

With any kind of high numbered eg. 3.55 or 3.91 rear end and that 383 you should be able to "melt" the tires off that swinger, ask me how I know. Once ya got that engine running good I'm going to suggest a 750 vac carb.
 
Oh! Awesome! Thanks! I was a poor kid in HS so its my first time with MOPAR. Ill get back with you guys on the reading once I get to lowes to find an adapter.
 
demon seed said:
Quote: intial timing is a little less than 10 degrees and my distributor has a limit of 24 factory. Also have a vacuum advance.

Are you saying that the limit of 24 factory is the centifugal therefore giving you a total of 34 with the vacuum advance plugged off. First bump the timing up to 12 and you want the centri. to be fully in at around 2200 rpm. Hook your vacuum guage to the manifold like said above. What are the specs on the cam shaft and do you know what the comp ratio is. The ticking could also be a exhaust manifold leak so make sure your bolts are all tight and does the ticking seem to go away when you rev the engine up.
Click to expand...

When I rev the engine is louder. Everyone can hear it and it echos in the neighborhood. Sounds mechanical. No black residue around any exhaust and it sounds like its coming straight from under the valve cover. I dont know the specs on the cam or comp ratio. The guy I got it from said it was stock. Thanks on the advancement tip! Ill try to shoot the mark after the 10 line tomorrow and report.
 
Pull the valve cover off and look for a pushrod pushed thru the rocker arm, This is common on BB Mopars with stock rocker arms. It will also kick the lifter out on that cylinder and you'll lose all oil preasure.
 
If that ticking is that loud you've got something major wrong and I wouldn't recommend running it any more. As SG said pull the cover and check the valves, rockers and push rods. I'd also be willing to bet that you've got a lazy lifter that's not pumping up properly.
 
Make sure there is a cap on the 3/8" port that comes off the back of the carb.
As for the noise, get a video and post it up.
We will see what we can come up with.
I'll be out for a bit today but will check back around 5pm to see the progress and Video.
 
I went to LOWES and got a fitting. Plugged it up. Started the car and it takes my foot being on the gas to get it to warm up. Guess I got some carb tuning still. Once warm it idles good but the vacuum still reads 5. So I advanced it to what looked like 12 degrees. Just a hair past the 10 line. Sounds better, idles higher but doesnt sound too high. Vacuum is now at 7 with a ecstatic needle still. The ticking is definitely in the engine somewhere seems to be louder on drivers side but not sure if its under the cover now. Almost like lifter valley. Hard to pinpoint with the fan in my ear too. But that is where it is strongest. But its not obnoxious like I thought yesterday. I might have been exaggerating from frustration. But its definitely noticeable. Also when I gave it slight gas the rpms didn't come down after I took my foot off the gas, they kinda slowly went up and stayed. Had to put it in D and back to P to get it to come down again. Not sure what that is about. In D the idle comes way down almost close to a rough idle. Also I noticed today that my fuel filter was filled full of gas. It had hardly gas I could see in it but it still ran the same. Not sure if that means anything. Yesterday I saw it full.

Ill try to get vid up before the end of the day.
 
So I ran the car again. Sometimes when I give it gas it pops (small backfire). I found out that the cars transmission slips (Awesome!). Seems hot but the gauge says its fine. Maybe the transmission is the culprit? I know there is something wrong in the valvetrain. Had a friend over and he said yup, I can hear the clicking in there. Sounds like it comes right under the intake. So Im thinking that the transmission might be making this car change rpms out of no where. As far as the vacuum issue maybe the springs or lifters?
 
Ummmm....not tryin to be a butt, but you've spent so much time postin here you couldda tore it apart by now. Valvetrain diagnostics on a B motor is so easy a chimp could get her done. Knock it out and let us know what you find.
 
StrokerScamp said:
Ummmm....not tryin to be a butt, but you've spent so much time postin here you couldda tore it apart by now. Valvetrain diagnostics on a B motor is so easy a chimp could get her done. Knock it out and let us know what you find.
Click to expand...

Posts take like 2 minutes of my day. What stops me is job, weather and lack of knowledge. I spend most of my time researching diagnostics. Not trying to be a butt either but maybe a point in the right direction would be nice. Like to some books or good links. Im completely new to all of this stuff.
 
Books? Point you in a right direction? Man quit bein a frikkin puss and go tear into the thing. HTF do you think all those books were written? guesswork standin on the sidelines? Stop bein a scaredycat. Go learn somethin for YOURSELF. Whether you realize it or not, I've given you the best advice of anybody. Learn if for yourself. there's no substitute for experience. Wanna tip? Ok, here's a good one. When removing the rocker shafts, make SURE when you reassemble,that the oiling holes in them go DOWN toward the head and OUT toward the valverprings. A lot of people take note of the notches in the shaft ends. This isn't always positive as I've seen shafts with notches in different positions. Always look at the oil holes. Now go learn somthin dammit. Oh and if you get hung up, we'll be right here. Readin books and links ain't gettin it DONE.
 
Get a shop manual for your car, link: http://www.moparmanuals.com/mopar/main/home.asp
The shop manual will contain trouble shooting pages.
Remove the valvecover, start the engine( will get greasy) put your finger or a wooden stick on the rockerarms, one by one and see if the noice goes away.
If it gets quiet remove the lifter and have it cleaned, put it back and restart.
One way to see whats wrong.
 
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