69 340 timing chain questions - help!!

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George R

George R

Mopar Nutcase
Joined
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OK guys,
Most of you have been following my problems with my 340 stumbling and bucking. I finally threw in the towel and pulled the timing chain cover off to see if I installed the chain wrong.
What I found was the CAM timing mark at 12 O clock, and the CRANK timing mark also at 12 O clock. I pulled off the drivers side valve cover, and both valves for cylinder #1 are closed indicating compression stroke.
I then pulled off the distributor cap, and the rotor is pointing at #1 terminal on the cap.

All looks AOK to me, except I remember putting the CAM timing mark at 6 O clock, and the CRANK timing mark at 12 O clock per the instruction manual diagram.

Is the chain installed correctly as is?

If you need pictures, now is the time to ask for them as I didn't remove or change anything from my initial installation.

PLEASE respond if you can help.

Thanks in advance,
George
 
Make sure you are really on TDC before power stroke.Check timing mark on balancer, should be at zero. Cam mark should be at 6 o-clock, crank at 12 o-clock.By the sounds of your valves, maybe you set up wrong the first time?
 
MtNemoMopar said:
Make sure you are really on TDC before power stroke.Check timing mark on balancer, should be at zero. Cam mark should be at 6 o-clock, crank at 12 o-clock.By the sounds of your valves, maybe you set up wrong the first time?
Click to expand...

I would turn the engine counter clock wise (looking at the engine from the front) 45 degrees or so then turn it clock wise and see if air is being forced out of the #1 spark plug. If it is then you are on #1 compression stroke. The cam mark should be at 6 o-clock on TDC #1 compression stroke, not 12, so if you are at TDC #1 compression stroke and cam mark is at 12 it needs to be changed to 6 o-clock.
 
Play with it!
Pull all the spark plugs to relieve all compression. Grab a socket and 1/2" pull bar and turn the engine in the diirection it runs. You'll see the timing marks go to where you set them up and back to where they are now. One reveloution of cam sproket is two revolutions of the crank sprocket.
or
Close it up and stop playing with it.
 
George

Verify TDC on number 1 cyl on compression. Timing mark on damper is at zero. Cam gear mark will be at 6 oclock. Crank gear mark will be at 12 oclock. Distributor rotor will be on number 1 terminal on cap.

Just like 340Fastback said. If all things are as stated above, then close it up.
 
when both marks are at 12 o clock, it is on #1 firing...when the cam mark is at 6 o clock and the crank at 12 o clock, it is on #6 firing...in other words, it's correct...
 
doug 371 said:
when both marks are at 12 o clock, it is on #1 firing...when the cam mark is at 6 o clock and the crank at 12 o clock, it is on #6 firing...in other words, it's correct...
Click to expand...

Agreed.

For it to be on #1 compression/firing both marks need to be at 12 O'clock. When the crank is at 12 O'clock and the cam is at 6 O'clock it's on #1 exhaust stroke. Also at the same time #6 is on the compression/firing stroke.

You have it right George.
 
The reason you put it at 6 oclock on the crank and 12 oclock on the cam is its EASIER to line up the dots. One more full revolution brings it to #1 tdc which is 12 oclock for both since the cam will only go around half turn and the crank goes around 1 full turn.
 
Well guys,
I put the front of the motor back together WITHOUT MAKING ANY CHANGES AT ALL, and the car is running like a brand new car. I took it around the block after getting the engine up to operating temp in the garage, and it misses no more. No stumble, no pop, nothing but smooth acceleration. WTF?! I didn't change anything at all. I looked at the timing chain, scrapped the gaskets off, and reassembled the car. Now, if it STAYS this way is another issue. There have been times in the past that I thought I had it licked, only for it to resurface on the next drive.
Any clues??

George
 
It was something stupid. Like a wire not on all the way, or something like that. It had to be soemthing you disturbed that you thought was good but wasn't. Nice job George, on purpose or not, you fixed it!
 
Well damnmit! Wonderful that it is better, but really leaves you smacking your head on the radiator doesn't it? I agree with moper that it had to be in the plug wire connections. Enjoy!
 
Nope.
After I hung up with you guys earlier this am, I took the car out again, and it was bucking/stumbling again. I said screw dis shtuff.
Bill (b67cuda) had sold me a MP electronic dist kit, still in the box with the wiring harness, ballast resistor, and the orange ECU. I installed it as soon as the car cooled off. I set the initial to 5º per the instructions, and it is not good, but perfect! I guess something inside the reman points dist I bought in August is screwed up. Maybe the advance weights are sticking open or something, because without any changes, the car ran like a top this am, then the next minute it was back to it's old tricks. With the new dist it runs awesome.
I mounted the kit so it couldn't be seen from the casual observer. You guys know how I hate to put mods on this car! LOL The ECU is mounted to the steel next to/behind the drivers side fresh air box. The ballast resistor is in the stock location, but I used another blue wire from another harness so the colors are the same as original. Only diff there is there is one more wire at the BR.
I wrapped the 2 dist wires in electrical tape to hide them from view, and put the connector plug in the wiring clips on the firewall so it is difficult to see.
I think it came out pretty good. I slapped it together in like 2 hours.
I still need to mount the ballast resistor and reinstall the fresh air box, but otherwise it is complete. THANK YOU ALL for all the help. I knew it wasn't something I did wrong. Damn points dist is only 4 months old, and that is how long I have been chasing this problem. I restored the whole rest of the car in 10 months! LMAO
Here are some pix........

George

Elec Ign install 001.JPG


Elec Ign install 002.JPG


Elec Ign install 003.JPG


Elec Ign install 004.JPG


Elec Ign install 005.JPG
 
There's an old saying that "99% of all carburetor problems are in the distributor" or something like that.
 
Good to here its fix. Now you can park it for the winter, LOL I hope my is running next year so we can hit some cruise nights together.
 
Ha! Well, it sucks that it was so much work to find the problem, but it's GREAT knowing that it's actually fixed.

5 degrees initial is not much. Did you dial in more advance once it was running?
 
Hey Adam, yeah I still have a bunch of small **** I was putting off until this was fixed so I'll be busy for a little while. Can't wait till we go cruisin!

Fourspeed, No I left it at 5º, and whatever the factory mechanical advance is set to. Car runs good now so I aint messin with it. LOL It doesn't ping at all even with the vacuum advance hooked up so I would imagine I could put another few degrees into it but I'll wait til next summer.

My wife and kids and I just took it to my fathers house, about 15 miles round trip. It was the most enjoyable ride I've taken in the car since I've owned it. Ran like a champ!

George
 
Glad to hear you have it fixed. Most of those MP distributors have 25 degrees in them so a good initial would be 10-13 for a total of 35-38. I ran my stock 340 with 13 intial and 38 total and it ran real hard on 93 octane pump gas no pinging.
 
Good to hear you may have it wipped George. Just thought I'd say I once had a rebuilt points distributors in a 383 that didn't run right. I checked the points and found them set at .007' so I reset them at .018" and started it up. Didn't run any different. Pulled the cap and rechecked and found the points at .007" again so I'm thinking how did they slip?? I had the screw tight!! So I reset them again and had a buddy spin the engine over and I watched them and rechecked them again and once again they were real tight. That's when it hit me. Possible bent shaft. I had my bud tap the starter over half way around and sure enough the setting was right there. Pulled the dist and spun the shaft by hand and could see that it was bent. Put in a new dist. and it ran perfect. If I would have known you had a rebuilt dist. in it I'd have mentioned checking that.
 
Glad to see it's fixed. I had almost forgotten about this, but years ago I bought a 273 factory dual point distributor for my car. Went through it, new points, condenser, cap, & rotor, just for good measure, before I put it in. Same kind of problem. It would run great & then start stumbling & generally run like crap. Cool it off & it'd run good again. Figured out the distributor was the problem because it did the same thing in my friends Challenger. Turned out the new condenser I bought was defective. Bought another condenser it was fixed.
 
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