Motor won't start

Good evening all,
Tim,
if you are running the Accel "Dual Synch " distributor it might be worth checking the position of the rotor arm. You can adjust the rotor position when you initially install the disi and phase the rotor.As they come from Accel the adjusting screws are usually not very tight and if the phasing is OK they are often left "as is" and can move. If you look at the base of the rotor shaft you will see two adjusting slots and either two allen screws for the early ones or torx screws on the later models. Might be worth checking to see if they are slack and the rotor has retarded itself. Probably OK but worth checking.
We are the Accel DFI EMIK for the UK, also TWM and Dynaformance, if you think it's an Accel problem I can put you in touch with the right people at Accel for help.
Regards, Mike
Welcome Mike - I'm guessing you are the force behind

Huddart Engines

your input to the forum will be greatly appreciated I'm sure and fingers crossed Tim will have it sorted soon.
 

Tim Kay

Lifetime Supporter
Mike,

Great to have you aboard. Coincidentally enough I happen to speak with someone at Accel earlier and although no mention of what you have eluded to (which I intend to act on your suggestion) he suggested the following:

1) hook up my laptop to my ecu and during cranking of the motor take note if I get an rpm reading
2) if the program is getting an rpm reading then the ecu is communicating with the dizzy. In which case, probably not a dizzy problem.


I performed the following test today:

1) MSD white wire trigger test on the coil wire (repeating same procedure as before, just checking again) Plenty of spark\voltage.
2) Checked the rpm reading on laptop as suggested by Accel tech, yes I get a reading while cranking the motor.
3) Hooked a timing light to my coil wire to see if the light blinks while cranking the motor, does not light up (but it does light up when I do the white wire trigger test).


This tells me that even though voltage is sent through the coil wire during "manual stimulation" (for lack of a better description) and not during ignition switch cranking of the motor, there must be something about the MSD and\or ECU and\or wiring between the two that is bad.

Jac Mac, Paul, Ian et al, your help and responses have been most appreciated and I thank you. I could not have got this far without you but it may be wasting your valuable time to continue with the suggestions. At this point I may take this in a different direction and I certainly didn't mean to run you guys on a wild goose chase.

I would check the harness from the engine to the ECU and also the chassis power harness to the ECU. Sounds like the MSD unit is powering up but no trigger from the ECU. Give us the AEM model number. Get your VOM out and sweep the main ECU chassis power harness first.
As A-tomic suggest, next I think it's necessary to jump into the wiring between the ECU and MSD box and I will let you all know what I discover. (btw, my ecu is AEM Universal Engine Management System)
 
Tim,
I had a look at the AEM Site and your engine management unit. Since you can talk to the controler, I would check the engine harness first. Since these units come with factory cables or custom connectors which I don't know what you have or history of your build. I would get a pin out of the connector and check to see if it's a custom connector and if the pins are making contact in the ECU. If that's OK check the rest of the harness for stressed areas or breaks. Over time I have found that tie wraps can cause stress on a harness cause breaks that can't be seen. I would sweep the cables for continuity.
Dave
 

Tim Kay

Lifetime Supporter
David S,

I had a look at the AEM Site and your engine management unit.
Thanks for taking the time.

The harness was pro-built specific for this application. Not only was it the right way to do it but I had no choice because I have no clue when it comes to electronics!! (I'm just a simple reinforcing steel guy ya see) For example, VOM - no idea, sweep the cables - no idea! I gather from you suggestion it's checking all the wires for continuity.

For now, when I can address it again in a few days or hire someone competent, looks like a little "pic-n-poke" strategy is on my agenda.
 
Tim.
No problem, I am just a retired overpayed unskilled auto assembly line worker. VOM is Volt Ohm Meter. There is a diode test on most of them now that gives an audible tone that you can use instead of the resistance setting. Touch the two leads together you get a beep. One lead on the pin of the harness the other on the end of the wire. You get a beep the wires good. I would test the part of the harness that goes to the MSD unit and the transistor pack in the distributer. This unit replaces the points that was used in the old system. That's why you need the pinout for the harness or the ECM to tell you what goes to what. The guy that does your trouble shooting will need this info.
Dave
 

Tim Kay

Lifetime Supporter
Thanks for asking Paul but nothing to report just yet.

I didn't want to get “my team” (all you guys) back on the project until I had something to go on. Sorry to keep you all hanging. As of right now, my schedule is only allowing intermittent attention to the GT40 :juggle:
 

Tim Kay

Lifetime Supporter
She's Alive!!

Yes, the 'short' of it is, we are back on the road!

After a full sweep of the harness with VOM (thanks David Sturch) all seemed in order. Took a little brain scratching since it's not my forte but well worth the time to draw a usable schematic.

Dropped in a brand new dizzy and the music started playing :thumbsup:

Synopsis:
 
Tim,
I will have to send you your Diploma now that you are a GM Factory Trained Tech. Of course I never saw any dealers tech's in the plant. Here they charge $120.00 just to change parts. You did it the right way and saved yourself some money.
Dave
 

David Morton

Lifetime Supporter
Tim,
This is about to create a void in my life. I had so looked forward to all the posts it was generating as it went on. Can you please find another problem?
Dave
 
Tim,
PM me your address and I will mail you down a ferrite core and some shrink wrap tubing. I want you to loop the harness from the distributer through the core. This is an cheap way fo filtering out EMI.(electrical magnetic interferance) I always like the Mallory Ignition parts even though they are the same company.(Accell) After 5000 miles that is a bit premature . I don't want to see you changing it again.
Dave
 
Bit late on this but good to hear you're back up and running Tim. Out of interest, does the distributor provide 2 signals to the ECU? - ie reference and sync (cam position for sequential injection). If it does, it is possible that the ECU showed RPM as it got the ref signal, but without the sync was not happy to trigger the injectors/msd.... just a thought...



Tim,
This is about to create a void in my life. I had so looked forward to all the posts it was generating as it went on. Can you please find another problem?
Dave

To keep David happy, someone pop round and 'snip' a wire.......:shocked:

.........only kidding! :thumbsup:
 
I'm with David. I always went to the posts on your problem as it was such an interesting mystery/thriller. Please can you find another one???

After you burn rubber for a while, of course.

Dalton
 

Pete McCluskey.

Lifetime Supporter
Tim, I've been lurking here too, I didn't chime in because my knowledge of electronics extends to backing into the electric fence in my horse paddock.
I'm glad you got it sorted, make sure you take A-Tomic up on his offer.
 

Tim Kay

Lifetime Supporter
...my knowledge of electronics extends to backing into the electric fence in my horse paddock
The story I heard was your horse was pushing you out of the paddack cuz you had no business being there :D And yes, I am going to take A-tomic up on his generous offer.

I always went to the posts on your problem as it was such an interesting mystery/thriller. Please can you find another one???
Maybe you'll all like this one then. Come on A-Team, see if you can assist in advise on finding my new girlfriends G-spot? All suggestions will be considered. It's a mystery and a thiller!!

...does the distributor provide 2 signals to the ECU? - ie reference and sync (cam position for sequential injection). If it does, it is possible that the ECU showed RPM as it got the ref signal, but without the sync was not happy to trigger the injectors/msd.... just a thought...
Paul, your assesment is dead nuts on :thumbsup: I am sending it back to Accel to confirm and repair the issue, so I'll have a spare on the shelf. You know how it goes, buy two of something and you'll never need it again.
 
Guys,
This is what I am refering to, the filter that goes in the harness from the ECM to the modual in the distributer. Since they use mosfets for the trigger in the modual they build them cheaply. (Chinese Mosfets) or the whole unit contracted out. If they designed them properly and used brand name parts this would not happen. The fix I have for Tim is low cost to shield for noise and it may run a bit smoother. He is just going to loop the harness through a (ferrite) Toroid Core and cover it with heat shrink.
Dave
Mallory Ignition :: Products
 
Last edited:
Guys,
This is what I am refering to, the filter that goes in the harness from the ECM to the modual in the distributer. Since they use mosfets for the trigger in the modual they build them cheaply. (Chinese Mosfets) or the whole unit contracted out. If they designed them properly and used brand name parts this would not happen. The fix I have for Tim is low cost to shield for noise and it may run a bit smoother. He is just going to loop the harness through a (ferrite) Toroid Core and cover it with heat shrink.
Dave
Mallory Ignition :: Products
Hi David
I'm having issues with my Accel dual sync distributor. My engine tuner says the distributor will not hold its timing; ie timing is inconsistent or erratic. Do you think that your fix for Tim's will fix my problem? If so, could you send me this filter. I live in GTA (Newmarket).
So now he's going use MSD crank trigger and modify a MSD distributor for cam sync.
I'm using Motec M800.
Thanks,
Ken
 
Ken,
The distributor modual takes the crank timing off the cam. I don't know what a dual sync is other than maybe two pick ups like the older dual points distributors. Noise will degrade the signal. A cold solder joint in the modual or bad solder will case it to drift once the engine starts to heat up or not work at all. Your Motoc is a good unit, run the diagnostics on it. I doubt it's the ECM. Even distributor gear wear will cause drift or shaft bearing slop. I know the Motec has logging so check the log and see if the setpoints are constantly changing or resetting. That may give some idea where to look.
Dave
 
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