Why is my dwell always out of spec

bd1308 · 01-17-2005, 06:39 PM

Okay, I adjusted the dwell to 45 degrees. I screwed the screw all the way in and put the cap on and adjusted timing to spec. Everything was fine. Car was acting funny today so i checked the dwell and suprise suprise it is 50 plus now. Do i really need to whail on this screw or do i need a new distributor? I heard that they could be rebuilt....something about the distributor shaft wobbling? Could anybody help? Dave? Beuler?

John Rogers · 01-17-2005, 07:35 PM

Sounds like the rubbing block is wearing very quickly. I had that problem on two engines and that is one of the reasons I went to a points eliminator such as Compufile, etc. Good luck

bd1308 · 01-17-2005, 07:40 PM

is that really going to help....i mean is the hall effect sensor a non-contact thing...or what? is there any downside to them?

Jared at Pelican Parts · 01-17-2005, 10:51 PM

Could be that the shaft is worn... To be perfectly honest, converting to hall effect is a much better option... And there is no contacting of parts with a hall effect. There really isnt a downside other than it isnt stock...

Jim Chambers · 01-18-2005, 06:35 AM

Be very careful in tightening the screw. It doesn't need to be real tight to hold. The problem could be that it has been overtightened in the past and stripped the threads in the plate. That allows the points to move on their own.

bd1308 · 01-18-2005, 08:09 AM

it was firm when i did it last time, it started to slip during the snow and ice we had in KY. whether or not it was correlated I will never know btu I do know that my dwell is well into the 50s now. I saw a 009 in Ebay, will this work in my car? I have a D-Jet 1974 2.0L

Jim Chambers · 01-18-2005, 08:16 AM

009 will work (050 is better) only with carbs. You need stock distributor with FI points for D-jet. Grab the rotor and see how much lateral movement you have. Also, make sure there is a little hi-temp grease on the cam. I think they are loose and sliding closed. High dwell indicates close point gap. If the distributor shaft were the problem the dwell would vary some while the car is running at a stable rpm. If you are starting with 45 degrees and moving to a steady 50+ degrees the points are closing for some reason.

bd1308 · 01-18-2005, 08:24 AM

would the wrong type of grease cause similiar problems too? I mean someone above mentioned the point rubbing block was wearing away. I should just get a new point and see if it gets better

bd1308 · 01-18-2005, 08:25 AM

the point i replaced was the very first one i have ever replaced, not to mention that its the first time i had to set dwell, open the distributor, etc....whoo hoo!!!

bd1308 · 01-18-2005, 08:38 AM

hot Diggity!!!!! re-built dizzy from napa for 62 bucks (prolly plus core)....and plus i am rooming with the KY NAPA owner's son....

looks like mine too, which is important

bd1308 · 01-18-2005, 08:41 AM

beck-arnley rocks!!!

John Rogers · 01-18-2005, 12:03 PM

If it is cold enough for snow then the grease that should be on the rubbing block is not doing too much. If the engine was warm when you replaced the points then they could loosen slightly when it gets that cold. You mentioned that the dwell is still changing, that tell me that the rubbing block is wearing quickly and will continue to wear even if you reset the point dwell to the correct value. A "points eliminator" has no contact so there is no wear and the swell will never change over time. The Compufire in our 1974 has been there nearly 7 years and never been touched! Good luck

Dave at Pelican Parts · Dave at Pelican Parts's Garage

Be certain to check any "rebuilt" distributor you get. Grab the shaft and try to wiggle it side to side. If there is any real wiggle, tell them to get you another one. Some of the rebuilds are just one step up from a "Tijuana Rebuild" (i.e., hitting it with silver spray-paint).

The 009 and 050 actually will work with the 1.8's L-jetronic fuel injection, because L-jet is triggered by the same points that trigger the spark. But everyone is quite correct that only the stock (or some other very similar) distributors will work with the D-jet system.

--DD

karlp · 01-18-2005, 01:48 PM

I used to argue with my points all the time.
I'd clean them and gap them and re gap them and file them down and grease them.
What I have been doing for the last few years is to buy a new set and clean them with contact cleaner, install them and use eye and the dwell meter to set the gap. I won't put anything between the contacts. Mine runs best at 46 deg, I'd guess meters vary a lot though.
I think what was happening was that I was getting crud in between the contacts from feeler gauges and files and just plain oily fingers and that it was breaking down the face of the points, changing the dwell. The points in my car now are ~ 18 months old and still straight and flat.
You know, the difference in gap between 46 and 50 is pretty subtle, as far as the points themselves moving is concerned.

What I would do is get a new set of points and install them. If you have to use a feeler gauge to get it started, clean the gauge real good before use. I think .012 is the recommended starting point? Put just a pencil point of grease on the distributor lobe. After it runs for a few minutes, take a Q-tip and clean up any loose grease. Set your dwell to the number you want and monitor it for a few days. It should settle down unless your distributor is coming apart.

Have fun

Karl

bd1308 · 01-18-2005, 01:56 PM

um, yeah. I was told to put a liberal coating of dielectric grease (i think) on the shaft. So what i shoudl do now is take everythign apart and start over. I actually have some contact cleaner so i will use that! Thanks guys.

bd1308 · 01-18-2005, 02:05 PM

yeah magic fingers are required for eye-setting points. I always nail either 13 degres or 85.....

Dave at Pelican Parts · Dave at Pelican Parts's Garage

A standard business card is almost exactly the correct thickness for the point gap. If you have a box of them, one from the middle should be pretty clean...

--DD

sean_V8_914 · sean_V8_914's Garage

pertronics or compufire is THE way to go. I thinnk they are well worth the 60 bucks. My Kragen dizzy was good after teh second unit. the first was as Dave said, wobbly shaft. mechanical points were groovy in the 70s man

bd1308 · 01-20-2005, 04:15 AM

psst...hey huys! thanks forthe help so far. I looked at my dizzy and grabbed the shaft....had about a CM or two of play...is that bad? and can it be fixed real easy, or do I need a rebuild?

Jim Chambers · 01-20-2005, 07:13 AM

I don't think you mean cm (centimeter), maybe mm (millimeter). A centimeter is about a 1/2 inch. Again, if the dwell meter reading is steady, not variable or floating while engine is at idle, a loose shaft if not the problem. You have been experiencing a permanent change, ie the points getting tighter on their own.