AMC Eagle Den Forum

The Mighty 258 => General Service and Diagnosis => Topic started by: Nightpath on April 10, 2014, 09:22:27 AM

Title: Setting timing from full timing reset
Post by: Nightpath on April 10, 2014, 09:22:27 AM

Howdy all,

Before I got my car, the old guy diddled with it, then his retarded son screwed the timing up so he could get it started. I figured this out after I got it home and called him (rough as heck to start, but after it warmed up it ran fine, same as my old one. The starter solenoid toasted, as well as a few other things are having issues. My HEI is in the mail and my mechanical Carter is sitting on the shelf just waiting for me to gut the vacuum lines and remove that shoddy Carter BBD.

So  here I sit, car will turn over like a champ and :censored: out the carb or backfire, but won't start. I'm going to rip the old crap out of it and prepare for the carb + HEI change over.

Questions :

1 - Should I do the full ECM Test Bypass and leave it at that, seeing as a HEI and different carb are going on?

2 - How do I set the timing to get the car started, from 0*, if the car won't start? Iirc, I can crank the engine over manually and set it at 0*, but I'd like to start somewhere that might actually get the car to start.

Thanks :)

Title: Re: Setting timing from full timing reset
Post by: BenM on April 10, 2014, 12:22:28 PM

There's no reason why the ECM can't control an HEI ignition. It works on the same principal as the Motorcraft ignition. In fact, there's very little difference in how they operate.

It should start fine set to 0º, the 258 uses very little initial advance compared to many engines. Make sure you're hooked up to manifold vacuum for the advance as the ECM will attempt to retard the timing once it warms up.

Title: Re: Setting timing from full timing reset
Post by: Nightpath on April 10, 2014, 01:35:42 PM

I want to make the engine as simple as possible. Leaving the ECM in the loop, IMO, would probably cause issues down the line.

Title: Re: Setting timing from full timing reset
Post by: carnuck on April 10, 2014, 03:35:00 PM

You would need a later HEI dist to operate the timing retard with the ECM. Total wasted effort unless you plan a GM TBI swap later. If it can currently start, turn the dist to #1 plug wire, pull and swap in the new dist with the rotor facing #1 and you should be good to go. As long as you have full 12VDC going to the HEI dist, you should be fine running it. The Eagle coil has resistored power that must be bypassed in order for the HEI to rev correctly.
   On the BBD, before you remove the other stuff for the HEI swap, turn the key on and unplug it to see if it runs better after the dist swap. You might be pleasantly surprised. I know I was.

Title: Re: Setting timing from full timing reset
Post by: Amc1320 on April 10, 2014, 05:38:32 PM

I wanted to keep mine as simple  as possible too

I have the HEI as well

No computer, no ECM , don't need any of that

One wire from HEI to 12 volts (key on) from  the selenoid , no feeback carb like you have

Starts instantly, idles smooth like butter, accelerates like a champ

I ran vacuum from dist to ported vacuum on carb, works perfect

I set timing by ear, always have, advance it till it runs nice, if it pings under load back it off a tad til you find the sweet spot

I eliminated three miles of hoses and wires

Title: Re: Setting timing from full timing reset
Post by: carnuck on April 10, 2014, 07:13:59 PM

My '84 J10 is going to be the simplest system possible. HEI dist with LPG but I'll be running an AW4 so the throttlebody will still be there to run the TPS to control the trans shift points. No need for fuel pump (vapor system)

Title: Re: Setting timing from full timing reset
Post by: Nightpath on April 10, 2014, 08:31:25 PM

The car won't start at all. It'll turn over and that's it. It started to run a tad bad before this happened, same thing as my other Eagle. When I put in the HEI distributor (from Skip White Performance, same as before from this auction http://www.ebay.com/itm/AMC-JEEP-232-258-4-0-4-2-6-CYL-HEI-DISTRIBUTOR-6511-CL-/350971747140?pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr&hash=item51b78bdb44 (http://www.ebay.com/itm/AMC-JEEP-232-258-4-0-4-2-6-CYL-HEI-DISTRIBUTOR-6511-CL-/350971747140?pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr&hash=item51b78bdb44) )  I had to go back to 0*, could just get it running to get to a mechanic.

Keep in mind before the HEI goes on I will probably have my mechanical Carter sitting on it to replace the :censored: computer controlled one.

Since I have to do the same thing, I have no idea where the heck the timing is sitting at now without being able to start the car, I have to set it back to 0* and work from there. If I do, I assume that I have to rotate it counter clockwise a small bit to get it to work. How much should I rotate the HEI?

On a side note, if I have the cash after getting my rear axle fixed, and giving motor a facelift, I might look into the GM TBI.

Title: Re: Setting timing from full timing reset
Post by: Amc1320 on April 10, 2014, 08:52:32 PM

You need to find tdc on number one piston then place all the wires in order, it doesn't have to be dead on to run, it might run bad but it will run