218 Timing Issues - Maybe? Im Stumped!

[Vintage Metal]

I got a 48 Plymouth with a 218.

Last night I wanted to check the timing because I kept thinking maybe there was something wrong, running like it was very retarded (no pun intended )

I loosened the distributor and removed the vacuum line from the carb. I plugged the hole in the carb to delete the vacuum leak. Started the motor (RPM around 450-500) and checked to see what was going on at the crank pulley. I couldn't see much so I shut her down and cleaned the the pulley to get a good visual of the timing marks.

I started up the car again and got to work. I could see where it was set so I started to make some adjustments. After turning it CW and CCW a few times, I noticed there wasnt much or any difference in the sound of the engine. So I drastically turned the distributor CCW and CW with no audible or RPM changes...very wierd.

I shut the car down and checked the vacuum advance unit. I sucked on the vacuum line and it appeared and felt like to be working good. I know its not working while timing, but sometimes you think of the darndest things. With that good I fired the motor again and messed with the distributor again with no changes.

Very wierd...no sputtering or speed up of the engine rpm.... NOTHING!

Any Suggestion to the issue im having? Is this normal? Im thinking I have a 'bad' distributor....weak springs maybe...I dont know...im "spitballing" at this point.

Thanks for any help!

[Rodney Bullock]

Do you have play in the shaft? I had mine rebuilt and set my timing a couple of months ago. When I move it there is a big change in it. I set mine 2degress before tdc and it starts and runs super. There is something wrong there, I finally set mine with a 12volt timing light and a 12 volt battery I did not unhook the vacum line. I started it and did not rev the motor.

[Young Ed]

I've seen the weights in the bottom get gunked up or rusted up and stick. Might not be the issue but wouldn't hurt to check them either way.

[Plymouthy Adams]

even with stuck weights you are physically moving the timing by rotating the distributor..that should in all likelyhood alter the sound and speed of the engine..now my question is this...what did the strobe of the timing light tell you in regard to indicated timing while moving the distributor..this is the true measure of timing over human sensors..

[Merle Coggins]

The real question is, did the timing marks change under the timing light flash? Often times a timing change will make changes to the idle speed, but you should be focused on which timing mark is alligned with the pointer while you're turning the distributor.

I can't think of a reason that the timing wouldn't change when the distributor is rotated.

Merle

[Rodney Bullock]

Right, if the timing light after moving the dist. did not indicate a change then something is really wrong.

[Vintage Metal]

Im using a older 'Sun Pro' timing light and yes the marks on the pulley did change ADV/RTRD when turning the distributor, like I mentioned, no change in RPM or runnability of the engine.

Edited October 25, 2011 by Vintage Metal
adding information

[Plymouthy Adams]

were you at operating temperature or still running with partial enrichment with the choke...I think you may want to get yourself a nice vacuum gage and try to power balance the carb. Have you recently tuned/verified tune up settings to factory? According the size and power of the engine as to whether it will show an lot of change on the distributor untill you approach the entreme on either end. Hard to go by ear on timing..trust your tools..

[Vintage Metal]

Car was running at 160 degree's temp, choke was not engaged. The carb was recently rebuilt and adjusted to get the idle to about 450-500 rpm per what I have read here on the forums.

There is adequate vacuum from the carb, but that is by feel, I will have to check by a guage.

I could go and adjust the points and condenser, but im not sure that would make that much a difference if rotating the distributor causes no change in the engine. Maybe I have bad plug wires?

[Plymouthy Adams]

I could well see the change in the light without effect on the engine if you wee turning the potentiometer on the gun (advance timing light) instead of the distributor body itself..

[Vintage Metal]

I could well see the change in the light without effect on the engine if you wee turning the potentiometer on the gun (advance timing light) instead of the distributor body itself..

The timing light I have is a basic-run of the mill trigger pulling unit. no special advanced knobs or switches. 2 battery cables and one cable for spark plug.

[Plymouthy Adams]

I had figured that much but was just stating a scenario where the existing conditions as outlined in you original post could exist..still baffled as much as you are not to detect a change in sound/speed of engine while moving the distributor..

[OldDad67]

You didn't mention what number plug wire you had it attached to.

[Vintage Metal]

I used #1 plug...the first cylinder at the front of the motor.

[Merle Coggins]

I think you're on the right track to check your points before going any further. They may be out of adjustment, which changed your timing, enough that you aren't getting good saturation within the coil. That would produce poor spark which may be why the engine doesn't respond to the timing changes.

Check/gap you points and/or check/adjust the dwell, then reset the timing and see what happens.

Merle

[Vintage Metal]

I wanted to come back and give an update of my findings.

I pulled the distributor out of the engine to change the points and condenser. What I did not know was there was 2 adjustments under the distributor. Nuts!

While out, I did a 'suck' test on the vacuum advance diaphram and noticed the diaphram was good, but the breaker plate was 'siezed' in place from the old grease.

I removed the breaker plate and cleaned up the bearings, put new grease in place.

Oiled up the advance weights and checked the springs.

I re-did the internal wires so they were not grounding out on the housing. Put a new set of points and condenser inside. The rotor and cap were new so I did not replace.

After clean, I put back into the motor, I inserted it back in its original place from how I removed it. I cleaned the pulley real good, got it to start and was able to manipulate the rpm with the distributor while it was running.

I set the advance at 2 degree's with the vacuum off the distributor.

It starts at a 1/2 revolution on the starter now.

Funny thing...the car wasnt advancing may have been the culprit to the overheating I was having. Since getting the distributor working as it should...I have not seen too much of a difference other than it does run a bit smoother!

Edited November 1, 2011 by Vintage Metal

[greg g]

simple trouble shooting ususally works to find the problem. You really do not need to disconnect the vacuum since at idle there is little or no signal from the carb. I am runing at 5 degrees BTDC, which seems to work with todays gas. Yu can also set the timing with a cavuum gauge.

There have been several threads on that procedure so I won't repeat it here, but it might be worth your while to look it up for the next time you need or want to set your timing. Glad you got it found an fixed and theat the engine responded to your ministrations.