225 Slant Six Crank but Won't Start (Fuel but No Spark, Dist. Rotor turns)

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SlingBlade

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Please help me. I have 1970 Plymouth Duster that will crank but won't start. The parts I have replaced are: Starter, relay, coil, and spark plugs.

I took spark plug out and tested but am not getting spark. I also took distributor cap off and can see the rotor turning. I don't know what else it could be??

So to recap.. the car cranks and I'm getting fuel but NO spark.

Thank you for any help I have been go ogling and trying to fix this car for weeks. It's starting to drive me up the wall!
 
First question is what do you have for ignition system, IE breaker points, or Mopar ECU conversion, other?

If you don't have a factory shop manual, buzz over to MyMopar and download one free

What do you have for testing?

You need a 12V test lamp, some alligator clip leads, a spark checker, and a multimeter.
 
I believe the car still has stock ignition system. I have a cheap digital multimeter from harbor freight for testing.

My guess is no power to coil / distributor or have bad distributor. How do I test for these?
 
Points are gapped at .020. Too close and the coil never gets a chance to build power, no fire at plug. Too far apart and the points never open, no fire at plug. Usually a tolerance of .005 will run
 
2 Darts is assuming the OP has a points ignition. He didn't tell us or post a photo. 1970 was around the time they switched to electronic ignition. My 1969 was points, at least until I installed a Crane Cams XR700 electronic setup.

With multimeter, measure VDC from BATT- (or engine block) to coil+. Should be ~12 V while cranking, and drop to ~8 V when running. Run a jumper from BATT+ to coil+ and you will insure the coil is powered, but <5 min or the coil may get too hot. If nothing, remove the factory wire from coil- and use a jumper to touch coil- to block. Each time you lift it you should see a spark on the in-line spark tester you should have bought ($5 Harbor Freight) since you first asked. Then, see if your distributor points (or ECU) does the same as you crank.
 
^^As above^^. How many low voltage wires come out of the distributor, IE one should come out of the housing and go to coil NEG terminal

After you measure voltage to coil+ "cranking" then move your meter over to coil NEG and ground. With key on the voltage will be either "same as battery" or close to nothing. "Bump" the engine and see if it changes. This will show the points are opening / closing and actually conducting.

Remove the cap and look inside
 
Ok I went back to harbor freight and got me a 6 volt / 12 volt circuit tester (looks like a screwdriver and lights up ) lol

With the ignition on the light is on while touching the positive on coil. The light is also on while touching the wire going from the coil to the distributor. I wished I could post a picture of the contacts inside of the distributor cap. They looked burned and sort of flakey. Also the metal tip on the end of the guitar pick shaped thing which spins is black looking.

I will try replacing the distributor as it looks like it has power going to it but I don't gt spark from the spark plugs.
 
The points open and close so depending on where the engine is stopped they may be open or not. You should be able to observe this by watching them as you crank the engine. To crank the engine from under the hood, jumper the two large exposed terminals on the starter relay with a metallic tool such as a screwdriver.

Also, with the light on the coil NEG terminal and the key "in run" cranking the engine should cause the light to go on / off. If it stays either on or off, "on" in your case, you have found the problem..........bad points.

By the way, leaving the key "on" with the engine not running can "fry" the points.

Have you got a shop manual? Download one from MyMopar.
 
Ok here's where I'm at. I replaced the distributor and wires. Now I actually get spark but the engine still won't fire up. To be fair I'm not sure I got the rotor in the right spot as I just slapped the new one in without marking where the old one went. Would having the rotor off or timing off cause the car not to start? I mean it doesn't even act like it wants to. Maybe a fart and then nothing.

Do you think taking the number one spark plug out and adjusting everything to top dead center would help? I'm not exactly sure how to do this.

Thank you for helping me.
 
I'm sure it's probably out of time. The problem with slants (look at underside of dist) is that the advance / retard range is pretty limited. There's a slot on the engine end of the clamp and a slot on the dist. end. "You might" have enough range between the two

So here's the thing.............

No1 fires every OTHER time the timing marks come up. your job is to determine the CORRECT rotation. This is also a bit more difficult with a slant

Remove the no1 plug. Devise a way to stick your finger in, or something else to "plug" the hole and feel for compression. A compression gauge also works.

Now teach yourself how to bump the engine over with the starter relay. It has two exposed large terminals. Just jumper those with a screwdriver. Make certain the engine is in neutral (or park)

Bump the engine until you feel compression. You may have to "go round" a couple of times. When you just start to feel compression, stop and "look for" the timing marks. (NOTE You will not have to rotate the engine very far at this point) Gently bump the engine around until "the marks" come up to "where you want" the timing. Say, 5* BTDC. After this do not move the engine.

Now loosen the dist. so you can move it in the bracket. Move the dist body CW until you are sure the points are CLOSED. Clip a voltmeter or test light to the NEG coil terminal. Turn the key to "run."

The light should NOT light, or the voltmeter should read pretty low.

Now slowly rotate the distributor body CCW (left) SLOWLY until the light just lights, or the voltmeter "comes up" to 12V

AT THAT POINT snug down the distributor

NOW gently put the cap on, and "notice" where the rotor is "coming to" which wire tower. THIS IS where no1 should go regardless of "where it was."

Now install the rest of the wires going CW (right) 1-5-3-6-2-4

Now start the engine
 
Ok so I went and swapped my wires to the correct firing order. Before I just had them 1-2-3-4-5-6 ( yes I'm a newbie here ). After I have corrected the firing order the car definitely is trying to putter more but by no means a lot ( like it would be if it was about to start ). I honestly don't think fuel is coming into the carb at all. I do see some oil though. Bad pcv valve maybe? Another thought is after I tried cranking it with starting fluid down the carb It smelled burnt and there was some smoke coming from the carb / filter area???

You have been a great help so far. Do you know what I am dealing with here? I'm guessing it's a mix between the carb needs rebuilt, bad pcv valve, and fuel pump or fuel line clogged?

Also possibly compression? Idk about thus though. I wasn't the most scientific person putting the new distributor in but I had the rotor pointing to the number #1 wire.
 
FIRST thing to do is get timing right because "that is what" you messed with. You can check timing "on the starter" with a timing light.

Some of the parts stores (O'Reallys) loans out some tools you might check them for a timing light and compression gauge if you don't have one.
 
I'm not sure how comfortable I am with running the starter long enough for me to figure out the timing with a light gun. ( remember I am still a newbie ). Plus I don't have a light gun available to me I would have to go rent or buy one.

But could you please explain to me the difference between TDC and TRUE TDC? I am fairly certain I know how to find TDC of the compression stroke but what is TRUE TDC? I keep reading posts about finding tdc then turning the pulley the opposite direction until the cylinder comes back up on the compression stroke again. Then deviding the two marks to get true tdc?

I am sorely confused on why I need the extra steps?
 
OK, some engines are worse than others "at doing this" but it is possible on most? all? engines with harmonic balancers to slip, as they are a hub, a rubber material, and an outer ring. So if the outer ring slips, the timing marks are no longer correct

Secondly, "with these old girls," mixing of parts over the years is VERY possible. Depending (this is in general, Chevy included) when you get into trucks motorhomes, all the rest, and the early Mopar V8s up through 69, the timing mark and pointer tab were in different places, so you might not even HAVE a mark that could be correct. That is, EG, an early timing cover with a later engine / balancer on something like a 360 V8.

SO to make certain the marks are TRUE you need a PISTON STOP. This is a device, usually adjustable, which you put into the no1 plug hole. This is NOT to stop the piston at TDC, but rather "someplace" "on the way up." So you put this stop in place, and rotate the engine clockwise, and make a temporary mark under your TDC pointer, wherever it stops. You now rotate the engine backwards, until it again stops, and make a second mark.

Now you'll have two stops, and the true TDC will be halfway in between. If the original mark is accurate, that is where it will be.

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The other issue is as I explained earlier. The no1 piston comes to TDC every time the timing mark comes up, but it only fires on compression stroke

There are TWO WAYS to determine compression stroke, (actually three)

1....The method I explained above, stick your finger in and feel for compression

2....Pull the valve cover, and bring the engine up to TDC. Then look at the no1 valves. Both of them are shut at compression, both of them are "about equally" open on the exhaust stroke, and both valves will move if the engine is turned slightly

3....Not really a method, "you can guess." Bring the marks up and put the distributor in with the rotor pointing "by the book". If it runs, "fine." If it does not the distributor is "180 off" that is 1/2 turn off. The right way to fix is to pull the distributor and rotate 1/2 turn. The "quick" way is simply to rotate the plug wires half way around the cap

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On that note, "3" You can actually "throw" the distributor in anywhere. Then bring the engine up on no1 compression, timing marks on about 5-8 BTC and look where the rotor ended up. Get the points to "just open," put the no1 plug wire in whever the rotor points and then install the rest of the wires.

You can NOT do this on all engines in the world. GM V6 are an example. (Odd /even fire) If you look carefully at a GM V6 cap, the towers are "paired" that is, two close together and then a space. On these engines you cannot "just move" the plug wires ONE tower. It won't run correctly.
 
Ok I am starting to understand the process better now. I will make another attempt later today to adjust timing again. Will let you know. Thanks.
 
No such luck. I figured out the original timing mark on the pulley is accurate so I rotated the engine twice around until the dist rotor pointed to #1. Still won't fire up.

I think my problem is adjusting the distributor now. Does the rotor have to be dead on top of the #1 wire tower when you go to crank? What if it's right before the tower contact or right after the tower contact ( it would send spark to #2 first ).
 
The rotor position might be tough to see "down in there." Basically it is coming "to" corner to corner, IE the rotor contact is moving CW towards the cap and should be aligned "at least" one corner of the rotor to the leading corner of the cap. It will NOT be "after." But remember distributor postion......which determines where the points open.......should be set first. Again don't do this at TDC, do it "where you want" timing set.

Bring the marks up to 5-8BTC or so, then adjust the dist body so the points "just open." Do this by rotating the dist "far enough" retarded (CW) and then "come back" CCW with the dist. body until the points just open. Use a test light, voltmeter, or ohmeter, depending on the situation. Doing that should put the timing VERY close. It WILL start and run.

AFTER you set the dist body, it should be easy to set the cap on/ off or mark the tower, and SEE where the rotor is in relation to cap.
 
My father is coming here to help me next weekend. He is going to bring a kit to rebuild the carb and a Guage to test cylinder compression. He said there could be a problem with valves or stuxk rings from setting too long? Who knows? Hopefully we will get this sorted out.
 
Get your timing and dist,firing order set CORRECTLY before you start messing with the other stuff.DO NOT MESS WITH THE OTHER STUFF.
 
I have both set correctly to my knowledge but he is going to verify my work before making any other changes.

As I said earlier I have the first cylinder at tdc on its compression stroke. I also have the distributor rotor on the #1 plug tower with correct firing order 1-5-3-6-2-4.

I do not think that those are the problem anymore.
 
Never heard it run. I don't think it has been driven since 85' according to the register sticker on windshield. They stopped driving it for some reason though.
 
You most definitely have a timing issue. If this hasn't been driven since 85, let's do first things first! I would ditch the points if this Dist. has them and install a Pertronix unit and fix any other causes you might be having. You really need a FSM, they are a valuable tool to help you learn. The blue covered motor repair manuals like this are good too and cover a wide range of years. http://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=motor+repair+manual&_sacat=0 Good Luck
 
I really think the best thing to do is get the car running with the new distributor and plugs that I installed before swapping it for electronic ignition. That way I can go ahead and rule that out completely and know it isn't ignition related. Get car running first then change over.

Thanks for ideas though.
 
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