engine and drivetrain Tii Dies Under Load

[OriginalOwner]

Yeh, that's "gotta be" electrical.  

 

Along that line, years and years ago I installed an ignition cutout switch, connected to the wire from coil to distributor.  Well, last year the switch itself crapped out.  Same problem as you:  I'm driving down the road just fine, then suddenly the engine isn't running.  When I removed the switch, no more problem.

 

So, might there be something wired-in somewhere from some former PO ??

 

Cheers,

 

Carl

[Parkertii]

ive looked for some sort of ignition cutoff switch as mentioned and haven't found one. I have also checked my grounds to see if this could be the source of the problem and they seem to be fine. I thought that there potentially could be issues with the aftermarket ignition system and while i have not completely ruled this out i find it interesting that i get spark while the car is cranking over but as soon as i lay off of the starter the car dies..... could this be ignition switch related? 

[ray_]

In a conventional system, during cranking the ballast resistor is bypassed to allow more current to the ignition. When one lets off the key, the ballast is then in line, resisting. If I remember correctly.

 

So yep it could be the switch, or something in the circuit.

 

GL,

[Parkertii]

This morning i switched out my ignition coil and crane ignition unit for a known working unit from a friend only to have no change in the problems my car is having. Still convinced that it is electrical related i cleaned all the contacts in the fuse box and inspected the fuses, which all checked out to be fine. I Also cleaned the contact points on all the grounds in the engine bay to insure that grounds were not the problem (this has fixed my dysfunctional tach though) . I also know that the timing on the ignition is where it needs to be and have ruled this out as well. 

 

Because fuel starvation was my first hunch i decided to completely rule this out again for safe measure.I replaced the electric fuel pump (even though i had 28psi on the old one), replaced the filter and checked the pickup screen in the tank along with my fuel lines for anything that could be prohibiting fuel getting to the engine. At this point i am also confident that my problem is not in the fuel system. 

 

The engine will fire as long as i have the starter turning the motor over but when i let off the key the engine turns off. In the rare event that i am able to start and drive the car it stays running for anywhere from 15 seconds to 30 minutes. When it does die it is a complete loss of power and just turns off without stuttering or showing any other symptoms. 

 

Because of this i am wondering if it is the ignition switch instead of any of the previous theories, but does anyone else have any other ideas of what it might be while i am waiting to find a new switch? Also from what i have read the ignition switches rarely fail, any insight on why/how they fail?

[Parkertii]

On a lighter note the house i broke down infront of today was owned my a BMW enthusiast who was happy to tow me home with his truck after rallying around the neighborhood with me in the passenger seat of his 2009 M coupe!

[ray_]

On a lighter note the house i broke down infront of today was owned my a BMW enthusiast who was happy to tow me home with his truck after rallying around the neighborhood with me in the passenger seat of his 2009 M coupe!

 

 

Haha, you have a fan!

 

What did you do wrt the ballast resistor?

 

From the net: Older ignition systems had a coil voltage dropping resistor that was bypassed when the key was in the "start" position to provide hotter spark while cranking..If that resistor burned out, the car would die when the key was released. The cure was to replace the "ballast resistor" or the "coil resistor wire"

 

... The ignition switches can fail, tho. You should be able to check it with a VOM.

 

GL,

[Parkertii]

i have the crane fireball ignition with the ps91 coil from crane, the ballast resistor is not used in this system and was removed. Ill pick up a VOM after work and test that out though. 

[Mike87]

I had issues with a Crane (back when it was Allison) where the car would just die. It happened multiple times. I replaced it with points and the engine ran fine. Might try that to diagnose the ignition.

[OriginalOwner]

ray_koke,

 

to sidestep just a bit, this ballast resistor thing.  Does my '74tii have one, and if so, what does it look like and where would I expect to find it ??

 

Thanks,

 

Carl

[BillWilliams]

There are two types of ballast resistors. One is a white ceramic deal with wires on the front and wires on the back. It generally sits above the coil. The other is a speaker looking wire and it hides in a bundle of wires coming off of the coil.

 

The white thing above the coil is the ballast resistor for the red coil

 

 

The gadget that puts the ballast resistor into and out of the equation is the starter relay box. That is mounted on the "firewall", passenger side high up. I guess if that went bad it could cause spark to fail to the motor but that is a WAG.

 

The silver box in the far right hand upper corner is the starter bypass relay box. The euro cars did not have these.

Edited May 27, 2014 by BillWilliams

[lilmo]

What kind of breakerless system are you running along with the Crane box & coil?  I think the choices are magnetic & optical.  I had the same symptoms when my Pertronix (magnetic trigger) failed years ago.

[JohnS]

ray_koke,

 

to sidestep just a bit, this ballast resistor thing.  Does my '74tii have one, and if so, what does it look like and where would I expect to find it ??

 

Thanks,

 

Carl

 

Carl,

  Your 74 tii uses the sneaky resistor wire.  I researched the specs of the resistor wire used for the 74 tii and it provides 1.8 ohms of resistance.  So, the 74 tii is set up to use the "red" coil (which requires a 1.8 ohm resistor) from the factory.  Other 74 and later regular 2002s also use the sneaky resistor wire, but it's shorter than the one used on the tii and only provides 0.9 ohms of resistance.  I know probably TMI ...

John

 

I call it "sneaky" because if you didn't know about it, you might not realize that the resistor is there.

Edited May 27, 2014 by JohnS

[Parkertii]

There are two types of ballast resistors. One is a white ceramic deal with wires on the front and wires on the back. It generally sits above the coil. The other is a speaker looking wire and it hides in a bundle of wires coming off of the coil.

 

The white thing above the coil is the ballast resistor for the red coil

 

The gadget that puts the ballast resistor into and out of the equation is the starter relay box. That is mounted on the "firewall", passenger side high up. I guess if that went bad it could cause spark to fail to the motor but that is a WAG.

 

The silver box in the far right hand upper corner is the starter bypass relay box. The euro cars did not have these.

I know that i don't have the ceramic ballast resistor. but tell me more about the speaker looking wire, what color is it? i thought that the ceramic option was the only one and this makes me wonder if it is the resistor and i have been over looking it this whole time....

 

I also don't recognize the silver starter bypass relay box... I may just be forgetting about having it, but since euro cars didn't have these is it possible to bypass this and have the car run properly? 

[Parkertii]

What kind of breakerless system are you running along with the Crane box & coil?  I think the choices are magnetic & optical.  I had the same symptoms when my Pertronix (magnetic trigger) failed years ago.

 

I am using the optical system with the crane ignition, i don't think that the crane itself is the problem being defective because i have a complete spare crane ignition system that i know is in working condition. I have the spare because i dislike being stuck and keep it as a backup . I now have my spare system installed and still have the same symptoms. 

[BillWilliams]

I have never seen the speaker wire resistor but is spoken of often here.

 

Here is a better shot of the starter by-pass relay.

 

Yes, if the starter bypass is "bypassed" properly, the car will run fine. When I got the touring, there was no bypass relay so I thought it had been removed. So I checked the schematic for a touring and it is just not there. I have seen a fellow or two remove the starter bypass relay when installing the Crane. Just has to be bypassed correctly.

 

 

The touring has neither the ballast resistor nor the bypass starter relay

Edited May 28, 2014 by BillWilliams