just rebuilt runs bad
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moper
Well-Known Member
the cap terminals are spaced at 45° intervals. (360°/8 ) Have you verified the oil pump drive is in properly? Just tossing that out there. I still think the cranking compression is low. The cam timing should be verified which means pulling that balancer and cover.
69dart340
Well-Known Member
I agree that the cam timing should be checked again. Especially since the machine shop had problems with your timing chain. As I posted on the first page this sounds way too familier to what I had when I assembled my 360's timing chain a tooth off.
I was also told by edelbrock when I called them before finding the chain off that if I installed a cheaper timing set that some manufacturers machine the timing sets to be 2-4 degrees retarded for emisions reasons. Edelbrock told me that if I pulled the front cover and it was lined up correctly that the issue lies in an "emmisions timing set".
I was also told by edelbrock when I called them before finding the chain off that if I installed a cheaper timing set that some manufacturers machine the timing sets to be 2-4 degrees retarded for emisions reasons. Edelbrock told me that if I pulled the front cover and it was lined up correctly that the issue lies in an "emmisions timing set".
purpledart
Well-Known Member
Gee all this tear down talk has almost got me fired up to work on some of our stuff. Lol I like following this!!
67Dart273
Well-Known Member
Not a valid argument. The only engines that will tolerate slow speed idle AT TDC are the old 70-80's "emissions" engines. Even emissions engines (generally) ran better at 5-12 BTC AT IDLE
Just for the record, you can time any Mopar V8 with the oil pump shaft in ANY position. You just might not wind up with the no1 wire in the cap "by the book"
THIS seems to me has some validity.
Bulldozer
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if it was my problem, i would start all over, by first,pulling the chain cover and verify the timing marks on the chain sprockets are looking exactly eye to eye. second, i would make sure i hadnt lost a cam lobe.third,check all your pushrods and valves,then i would button it all back up and rewire the entire ignition system with a factory electronic set-up making sure everything is set up to start on TDC.fourth,i would verify i have 5-7 psi fuel pressure and a good carburetor, non necessarily new, but good. this engine should start and run without any issues under this set-up. if it does not , then i would be looking at changing the cam and starting over again. TDC ,rotor on #1, plug wire on #1,correct rotation on cap,correct firing order, ballast resistor terminal plugs in their correct spot. 12 v and a GOOD ground,is your engine GROUNDED? good fuel pressure and good carb. what else is there to it ?a good factory electronic set up is the way to go.i have built MANY big block and small block engines and i have NEVER had a problem getting them to start and run right out of the box on the first 1-5 cranks on the starter. once it is running ,twist the distributor and find where it wants to run and then throw a light on it and go from there.i just dont see what the problem is.it has got to be somewhere in your ignition system, unless you had a guy that builds nothing but 350s all day,but even then ,its not that hard to stab a cam and get it timed, and make it run. my $0.02
Bulldozer
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and just to add... it will run, but not good, or barely if; incorrect firing order,reversed rotation on your cap or wires switched, the 5 ohm side and the 1.2 ohm side on ballast are reversed, stuck float in your carb, vacuum leak, poor fuel pressure, less than 12 v to the distributor .a bad ground to any ignition component, a tooth off on your timing chain,a flat cam lobe,stuck or bent valve or pushrod.there is really nothing left.chime in if im missing something here.im just trying to help.plug off your advance pod when starting it up and getting it to run. make sure all your vacuum leaks are plugged off . i cant express enough how correct these guys are when they say to set up your ignition with a factory system get it running good and then start adding your upgrades.i think electronic is the best choice because its plug and play without all the points and bs ,but thats just me
67Dart273
Well-Known Member
'S where we part company. A mechanical/ no vacuum points distributor is the absolute simplest system you can get. Gasoline engines of all forms used breaker points for at least 70 years. Those of us who are old enough but thousands and thousands of miles on a breakerpoint distributor.
I've been involved with PLENTY of people on this board who've had trouble getting a stock Mopar ECU system to run.
I agree, mostly, with the rest of your thinking.
Bulldozer
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i most definitely have NOTHING against points.i have ran them for years and years and i swear by them as well. my 318 70 coronet had the original points in it and after it sat 8 years that thing fired and ran and didnt miss a beat.if you havent messed with them before, they can be a little intimidating and it was only to suggest that with EI it would be a more reliable way of getting it to run out of the box. i ,personally ,have never had a problem with any EI with the exception of a melted box that had came with a car i bought. but either way ,returning to a factory setup is a good start.i wasnt trying to demeaner your advice....
I'm just going to throw this out there because my brains starting to get fuzzy-er,, maybe someone else can straighten this idea out,,
I'm still trying to wrap my brain around this. It's giving me that "downing a slushy" thing (too funny) you had mentioned.
I'll take a really close look.
I'm still trying to wrap my brain around this. It's giving me that "downing a slushy" thing (too funny) you had mentioned.
I'll take a really close look.
I'll be trying another coil. Thanks.
I will be asking the machinist this question again. I didn't understand the first time he explained it.
Not sure I follow the oil pump drive being in properly. How do I check?
Very interesting, agree the situation is similar to what you experienced. thanks.
Where are you located
I'm in Lusby, Md. and the car is in Bowie, Md.
your alittle to far or I would come diagnos it for you. I live in northeast pa. After reading all of this. It seems to me your machine guys don't want to help you or they would have offered. Something sounds amiss with your chain not working. There could only be one reason. They line bored the block wrong and the cam ended up to close to the crank. Alot of these shops put all 4 bolts in the cam retainer and starve the chain for oil. Sound to me like your cam timing is off. Or your lifter preload is tight.
Also msd box has a cylinder select. This is under the plastic cap Phillips screw. If it was bought and returned or bought used there i a possibility that one of the loops are cut. Your ignition will do what you are dicribing also. 8 no loops should be cut. 6 cut red. 4 cut red and blue. Make sure your wires from your distributor to the ignition box do not cross paths with the coil wire or any other high voltage leads. This will make the timing move around and cause a miss and sometimes bacfires from the plugs being fired twice.
Also msd box has a cylinder select. This is under the plastic cap Phillips screw. If it was bought and returned or bought used there i a possibility that one of the loops are cut. Your ignition will do what you are dicribing also. 8 no loops should be cut. 6 cut red. 4 cut red and blue. Make sure your wires from your distributor to the ignition box do not cross paths with the coil wire or any other high voltage leads. This will make the timing move around and cause a miss and sometimes bacfires from the plugs being fired twice.
67Dart273
Well-Known Member
I posted earlier, the oil pump drive has nothing to do with timing, OTHER than you will end up with the no.1 wire in a tower "not specified" "by the book."
The pump drive "slot", with the timing marks at TDC, should point towards the front driver side intake manifold bolt. If it's wrong, just "walk" the gear up with a distributor and drop it back down.
BUT TO REPEAT, that will NOT cause this problem. If you have the distributor and plug wires in a position where you have room to "swing" the dist, and can set the timing, then the intermediate shaft is no issue.
It's very Kind of you to even consider coming out to diagnose. Thanks. I'll check the MSD cylinder select. The thought of a bad line bore scares me. I hate to think it's something like that but I'm starting to believe it is.
Tomorrow, I will be using a stock points coil, new ballast, new Dist. cap, and the new points distributor. I'm going to once again verify TDC and timing mark alignment using a stop indicator, making sure both valves appear closed on the compression stroke, even putting my finger over the hole. Then I'll set initial timing to 5 BTDC. The engine should run, even if not perfectly. If it doesn't I'll try 10, 15 and back to 0. If it still doesn't run then it's definitely time for the machine shop to get back involved. Previously, in a nice way, the machinist said get your ignition straightened out, then come back to us if there is still a problem. If I'm unsuccessful tomorrow I'd be surprised if there is anything else I could do short of opening the engine and I think the machinist owes me that.
Thanks again.
moper
Well-Known Member
I think at that point you've exhausted all avenues and the shop should as Old said, if the shop had scruples, they would be offering to come over after work and if nothing else, work WITH you.
You said before they explained why the chain didn't work but you didnt understand. Can you get them to go over it again and you write it down? You don't have to understand at this point... Tell us what they told you, and maybe we can help you understand it.
You said before they explained why the chain didn't work but you didnt understand. Can you get them to go over it again and you write it down? You don't have to understand at this point... Tell us what they told you, and maybe we can help you understand it.
moper
Well-Known Member
It takes effort. but keep your composure. Right or wrong, it will help in the end.
I pretty much followed the script above. I was surprised that with the all stock ignition the motor ran half decent at 18 BTDC. Vacuum ports plugged.
I replaced the stock coil with the MSD coil and the engine would not start. Switched them around a couple more times verifying the MSD wouldn't work with the stock set up.
There were still a couple of things I don't understand with the stock set up.
- It also runs at 35 BTDC. If there was any pinging it was hard to tell.
- at 18 BTDC we could turn the dizzy CCW, the RPM increased, turn down idle. this could be done until over 35 DBTC.
- Seems there is still advance being induced without the vacuum connected. (Observed by a timing light against the timing mark.)
The next step is to test the MSD coil. I used a multimeter that I was not familiar with at it measured .8 ohms across the terminals. I will need to verify that reading. On Monday I'll put the MSD box and Dizzy back and use the stock coil and see what happens.
Thanks for everyones help on this.
67Dart273
Well-Known Member
Do you mean 18 as set at idle speed? Not very surprising
Which specific MSD coil are you using? I would think it should at least run, although some of the "big" coils will be hard on points. Did you check for spark out at the coil? Did this coil fire and run with the MSD box? Weird.
You need to specify exactly what you mean. Are you saying that you set the timing to these figures AT IDLE speed? You should be able to do so, then rev the engine to higher RPM, and SEE with the light where the timing is advancing
Turning the dist from 18 CCW and having the RPM go up TO A CERTAIN POINT would be "normal." You should be able to take a tach and vacuum gauge, and see where the timing CCW/ CW "peaks" the vacuum. Highest RPM is not necessarily where you "want" it. Some racers with a big cam run "locked" timing, IE no advance at all. The engine starts, runs, and is always at a fixed time. Not the best for starters, nor, usually, street use.
What you may be "saying" is that as you advance the timing (CCW) the RPM starts to go up, and AS the RPM goes up, this starts to cause the mechanical advance to kick in, which would raise the RPM still further to a point.
I said this before, and again---I'd "power time" the engine at high RPM to about 35, try a little more if no ping UP TO about 40, until you get a feel for how it will run.
After you set this high RPM timing point, CHECK the timing at idle "to see where it went." This is because, with an unknown distributor, you don't really know what the advance curve is. Because you now have a breaker points distributor, it PROBABLY has a "better" curve than some of the later breakerless "smog" stockers. Yanking out the obviously heavier spring on the advance weight may help.
Yes, 18 set at idle. 15-20 has been recommended so I thought that was good.
Using the 8302 blaster coil. The engine will fire but will not run. When running the MSD set up this coil works.
All the timing readings are initial. When I rev the engine they advance.
Understand.
This part I'm not clear on and will have to figure out. As you know the stock dist. has vacuum adv.. I was expecting that with the vacuum disconnect there would be 0 advance when rpm increased but it became obvious that isn't the case.
I'll try this.
Understand, thanks.
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