75 Dart /6 wont start. Electrical?

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Wolf M.

Wolf M.

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Hello all!
I have a bit of a tough one that I'm hoping someone can help me diagnose. I have a 225 slant in my 75 dart sport and it has been sitting roughly for about 17 years. Occasionally I would do some storage maintenance on her but I wont say she didnt get neglected. Here's my issue. She will turn over, tested starter relay, bought new coil and ballast resistor just to be sure, new plug wires. Also I am getting spark from plugs when pulled and tested now I did prime the carb with a quick shot of starter fluid expecting at least something but nothing. It seems like no juice is getting to her but I cant figure out why. Any of you all out there ever have this issue? If so what am I missing here?

Thank You!!
 
You say it has spark at the plugs. How did you test?
 
Here is an important point:

HOW did you crank the engine when testing spark?

EXAMPLE:

Situation A vs B

Situation A you test spark with key "in run" and you jumper starter relay under the hood. In this case the coil is firing from the "run" circuit and "let's say" you have spark. You think "OK." On the other hand, the "run" circuit goes through the ballast resistor, which can give you a weaker spark

In this case, a problem in the "bypass" circuit (read below) results in a "no start" condtion, because there will BE NO spark when using the key to crank

Situation B

You check spark by having "your girlfriend" crank the engine using the KEY. In this case, the "run" circuit is disabled, and the "bypass" (ign2, brown) is supplying the coil. If you have a wiring or other problem in the "run" circuit, this might give you spark where it would not run, but might fire and die.

The point I'm trying to make here is you can lead yourself down a rosy but thorny path
 
Compression, fuel, and spark

Need enough compression to run, problems including timing chain slipped, fuel washed down cylinders from such things as a leaking fuel pump or flooding carb, low compression

Fuel. Fresh fuel. Did the neighborhood kids "fill you up?" Is the fuel stale? Plugged?

Spark. Good spark, in both "start" and "run" and AT THE CORRECT TIME
 
So we test plugs two ways one being from the key inside while I tested and also jumped it from the starter relay when I was by myself. and Now that you are mentioning this, when I tested coil with multimeter with key in on position my coil was only getting 5.4 isnt that supposed to be around 7 with a ballast?
 
So a quick update. I yanked my valve cover one last time and it turns out my valve lash got insanely wacky and rocker arms way looser than needed.. has me wondering now.

Thank you all for the advice!
 
Wolf M. said:
Haha it's no big block at all. Just a plain old fashioned 225 slant.
Click to expand...
Oh...so why didn't you post in the slat six section where those guys live and breath that motor? Most of us here in the big block section probably threw away the slant that was in the cars we bought...I know I gave away my 225, fun story its in a early 90s toyota pick up now.
 
Start over and re adjust the valves. There are several threads about the procedure, some while running, some while the engine is shut off. Heres just one thread for example.
help-setting-valves-on-a-225.100536

If you try and adjust them without a fully warmed up engine add .003"ish to the factory gap to get it close. Then fine tune after you get it running. Just a couple thoughts there has been a couple threads lately about ignitions firing when cranking but not having power when on 'run'. Verify you have power to the ignition on both crank and run. Also verify that the rotor is at TDC on the power stroke when its on number one.
Do you have sufficient fuel pressure to the carb? Is crap clogging the fuel pick up and or filter?
Is your carb clogged?
When I got my slant the seller claimed it was in 'just jump in and drive anywhere' running condition. The fuel tank had crap in it, the fuel filter was clogged, the carb was clogged, and the distributor was off by one tooth.
 
Wolf M. said:
So a quick update. I yanked my valve cover one last time and it turns out my valve lash got insanely wacky and rocker arms way looser than needed.. has me wondering now.

Thank you all for the advice!
Click to expand...

Be careful. If this is a solid lifter engine "it might be" you have some stuck valves. Stuck OPEN. This means if you crank down the lash, you might be bending stuff next
 
Wolf M. said:
So we test plugs two ways one being from the key inside while I tested and also jumped it from the starter relay when I was by myself. and Now that you are mentioning this, when I tested coil with multimeter with key in on position my coil was only getting 5.4 isnt that supposed to be around 7 with a ballast?
Click to expand...

That is some low.

How I check spark. Do NOT use the stock (resistor) coil wire. "Rig" a solid core wire, even if a scrap of low voltage stuff "in the air" to a test gap. When cranking with the key, you should get a hot blue spark at least 3/8" and typically 1/2". Measure the coil+ voltage when cranking. Should be at least 10.5, and nearly same as battery when cranking
 
Wolf M. said:
Yes it started last year. She wasnt happy about it but it did start and run. And before I did this I made sure the varnish in the tank was gone for fear of sucking up garbage. She ran for about 10 mins then I turned her off and that was that.
Click to expand...

This right here might be a huge part of the trouble
 
67Dart273 said:
Be careful. If this is a solid lifter engine "it might be" you have some stuck valves. Stuck OPEN. This means if you crank down the lash, you might be bending stuff next
Click to expand...
This will happen. Before you put that valve cover back on,drizzlesome marvels mystery oil on the valves and spring and give them a couple of taps with a rubber mallet. Itll help free everything up.Stuck valve could me crappy compression and as mentioned above is one of three things you need.
 
charger426 said:
Oh...so why didn't you post in the slat six section where those guys live and breath that motor? Most of us here in the big block section probably threw away the slant that was in the cars we bought...I know I gave away my 225, fun story its in a early 90s toyota pick up now.
Click to expand...
My apologies as I thought my initial issue was electrical I just followed the yellow brick road here..
 
I agree with the others.You have ignition, and gas (spray can), but no compression because the valves are stuck open, Gunked up from not running much. Don't adjust your valves until you free up any stuck valves.

Oh, the deuce and a quarter IS the slant big block!
 
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