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Re-Rebuilding the 440-493 in a 1970 Charger

Many years ago now I had this issue with Don's control box. Ever since then, a diode is included when you buy a new FBO control box.......
Given my limitations on understanding electrical systems....
Is this "diode" something that attaches to the coil? Could you please elaborate a bit?

She is on one of those interactive conference calls with the headset and "zoom" type Brady Bunch screen bullshit. I offered to pitch in a couple days a week.
 
Or if you’re like me, relearning stuff you knew but forgot.
This seems to be occurring sometimes. I encounter some issue and wonder how I dealt with it before so I look through my old notebooks and read what I did many years ago before I even used these internet forums. It is surprising how much information got shared before these forums. I'm glad we have these but it wasn't like we were completely in the dark before.
 
My reason for suggesting the bypass spring swap was that in the last couple of years we’ve had a couple of builds that got new Melling HV or HP pumps that had lower than expected pressure.
For those builds, swapping the spring solved the issue.

AFAIK, the HV & HP pumps are supposed to come with the same spring, so if they were both supplied with the “correct” spring, there would be no change in pressure from swapping the spring.

If the spring doesn’t get the pressure to the desired point....... then a swap to a HV pump will be required.

On my 383, an original high mileage Mopar pump with the stiff spring provides about 35psi at 11-1200, and 80psi going down the track.
 
Given my limitations on understanding electrical systems....
Is this "diode" something that attaches to the coil? Could you please elaborate a bit?

She is on one of those interactive conference calls with the headset and "zoom" type Brady Bunch screen bullshit. I offered to pitch in a couple days a week.
This is what has been included with all his boxes for the past 10 years or so.

20221201_112335.jpg
 
The diode allows current to flow in one direction only, so following the instructions for orientation is key.
 
I've purchased two FBO ignition box kits within the last 3-4 years, and neither came with that diode, or any mention of needing one....so that's news to me. I forgot that you (KernDog) have that sweet Dakota Digital setup, so maybe that's the reason for your issue and why I never experienced that problem (old analog tach). Makes sense that a diode would fix the issue....if you can get the specs for what's needed, you can find them on the Amazon.
 
If Joel confirms what pt# I probably have a bunch.
Just went and looked at one. Very small numbers and my eyesight isn't the best anymore. First line is 1N4004, and the second row AF41 and I am not positive of the "A".
When this all happened 10 years or so ago, he started including the diode along with every box he sold. I haven't talked to him for years because he rubbed me on another matter. I just went on his sight and in the description of the HRR688 is this line "If your using a Tick Toc Tach VDO conversion please lets us know and we'll include the Tach feed Diode No Charge".
So he is just including the diode now if you have erratic needle movement. Seems kind of stupid to not send a .25 part along instead of having to mail it out after the fact.
 
Thanks.. I'll look for some 4004's . Pretty sure I have some... if not you can sub in a 4,5,6 or 4007. All will do the same job.
 
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Just went and looked at one. Very small numbers and my eyesight isn't the best anymore. First line is 1N4004, and the second row AF41 and I am not positive of the "A".
When this all happened 10 years or so ago, he started including the diode along with every box he sold. I haven't talked to him for years because he rubbed me on another matter. I just went on his sight and in the description of the HRR688 is this line "If your using a Tick Toc Tach VDO conversion please lets us know and we'll include the Tach feed Diode No Charge".
So he is just including the diode now if you have erratic needle movement. Seems kind of stupid to not send a .25 part along instead of having to mail it out after the fact.
Sounds like Don....:rolleyes:
Actually the last time I spoke with FBO was with Dana. I don't know if she's family/spouse/whatever but apparently she's taken over and is much nicer to deal with. I could still hear ol' Don's gravelly cackle in the background though, so he must still hang around for technical help.
 
Sounds like Don....:rolleyes:
Actually the last time I spoke with FBO was with Dana. I don't know if she's family/spouse/whatever but apparently she's taken over and is much nicer to deal with. I could still hear ol' Don's gravelly cackle in the background though, so he must still hang around for technical help.
Yeah, I was hoping he would sell the business years ago. He was trying to after his wife got sick, but it must not have happened.
 
Thank you Wayne.
On another matter....Brake bleeding:
I don't do a huge amount of brake bleeding but when I do, I'm anxious to get it done ASAP. Sometimes I have to pull of and do other things when I don't have the help from Mary.
I am thinking of buying a Motive brand power bleeder.
Check out this video.....


 
There are numerous options for this Motive pressure bleeder system.

One is the universal flat plate that would work on all the stock cast iron master cylinders:

Motive Products Power Bleeder Kits 0105​

4 out of 5 stars ( 113 )

Part Number: MVP-0105
mvp-0105_xl.jpg


$80.96

One of the others is this type that looks like it works with the aftermarket aluminum MCs with the 2 plastic caps:

Motive Products Aftermarket Power Bleeder Cap Adapters 1113​

Part Number: MVP-1113
mvp-1113_jr_xl.jpg

  • mvp-1113_jr_s.jpg
$44.96
 
I’m still waiting for the pedal-to-the-metal, mind blowing, change of underwear, test drive report.
I think he's waiting for new needle+seats for his flooding issue.
 
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