On my 2003 Blazer 2 door with 4 WD, I recently replaced the dist. cap and rotor with new AC Delco parts. When I removed the old rotor from the distributor, I noticed the electrical connection under the rotor at the 2 O'clock position was covered with white corrosion. I was in a hurry to complete the job and get this car back on the road.I buttoned it up and it ran well. But I was wondering how to replace this elec. connector and thought the only way may be to replace the distributor. So I went to Skip White Performance and sadly discovered their inexpensive 4.3L V6 distributor was discontinued! Q 1--Has anyone else seen this corrosion on the distributor elec. connector ? Q 2--Can you replace just the connector with out replacing the entire distributor ? Other than the coil and 6 spark plug wires, I think this is the only other connection and the only wire connection to this distributor. What would cause this corrosion to form ? What is the best way to remove this corrosion ?

 

Jim
You did say it ran well; that is good. Distributors are not to fun to change on these engines, but can certainly be done. If you look at the bottom of your rotor it looks somewhat like a fan; if you inspect you floor of the distributor there are two holes that sometime have screens over them. I believe there was a directive to remove the screens. You might want to goggle that, I think there is a gas that is formed and perhaps that is were your white powder is coming from. If you look at the old cap you will notice that the terminals are made of aluminum and you are hitting them with a really hot spark. The powder could be caused from that action.
I just reread what you said and went out to the garage and looked at my old distributor. The wire connection is outside the distributor is this where the white powder is? Unplug the connection and take compressed air, or vacuum it; take silicone electrical grease and coat the connection and put it back.
I replaced my distributor because I broke one of the plastic hold down ears off. Also my gear has some serious wear. If it bothers you could also just replace the module in the distributor, they are sold on Amazon.
I have also read some of the cheap distributor have the gear put on wrong and it was found out after installation would not start. If you do make sure to line it up with the old distributor. I elected for a more expensive distributor after reading this.

 

OP: Thanks for the reply. I am trying to avoid at all costs replacing the distributor because of the hassle. I just looked on Ebay to get some photo's of this wire harness. From looking at the photo in the Ebay site below, it is directly under the dist. cap spark plug wire no. 5 connector. This wire harness is mounted on the body of the distributor,.The white corrosion was on the inside of the distributor body.

https://www.ebay.com/itm/223705459170/

I appreciate the tip on the screens and will try to do a search on the forum and read up on it. I am guessing the idea of 'removing the screens' is to allow moisture and fumes to escape. When the screens get clogged up, it causes the corrosion to build up. This white corrosion on the wiring harness is on the inside of the distributor and seen only when you remove the cap and rotor. So it makes sense the moisture is inside the distributor is the cause of that corrosion. I may try to clean the screens with some WD-40 and a brush. I hope my photo site posted shows it.

I hate the thought of going back in to the distributor for several reasons. One is that it is hard to get to the distributor as you know. It is at the very back of the engine which means you have to lay on top of the engine to reach it. My Blazer is stock and not lifted ! But i still have to stand on my car ramps to reach the distributor. Two-I have a fear of dropping one of the tiny Torx screws that hold the cap and rotor on. Thankfully AC Delco has provided two each new Torx screws for such an event. I see all these beautiful new 2019 Silverado's and Sierra's driving around with high lifts from the factory. How in the world do they work on the back of the engine to replace a sender or whatever else lurks back there?
Yes, the 4.3L is now running smoothly, idling well and no static on my AM radio/ that was another post I made a while back..

 

Q no. 1./ You said: The wire connection is outside the distributor--- is this where the white powder is? The wire connector is located outside the distributor under the no. 5 spark plug entrance on the cap. So facing the distributor, it is at the 2 O'clock position and on the body of the distributor.The connector goes inside the dist. and inside is where I see the corrosion. So that supports your recommendation to remove the two screens to allow the gases and moisture to escape.


Q no. 2./ You said: If it bothers you could also just replace the module in the distributor, they are sold on Amazon. To replace this dist. module, do you have to remove the distributor from the engine ? I don't want to remove the distributor unless it is absolutely necessary.!

 

I am about to go into the dist. on my '03 and remove the cap and the rotor so I can take out and clean that three wire connector at the back of the distributor. I want to try to get the white corrosion off before it affects the operation of the distributor. Before I go in there, does anyone know exactly what the purpose of the connector is. My Haynes manual is spotty at best. While I am in there, I want to remove the two screens at the bottom of the dist. to prevent more build up of corrosion. There is a TSB tip on that the screens clog up causing the moisture to build up resulting in that white corrosion. I would hate to remove the connector and find out the adjustment is critical.

 

Take out that old rotten junk and install one of these:

https://www.ebay.com/itm/For-1996-05...3944%7Ciid%3A1

the connection on the back is for cam retard

 

Billy, that's a good deal, but I don't have the scan tool for setting Cam retard and if i did , I don't have the skill to do it. I would like to replace that 3 wire sensor under the dist. rotor that I found out was the CMP sensor. It is corroded and will start to give problems soon. I would like to know if I could remove the CMP without having to set the cam retard.
BTW when people on this forum were using the Skip White dist. deal , they recommend you replace the chinese cap and rotor with the AC Delco cap and rotor. Some have gone one step further and said to also replace the CMP sensor for an AC Delco one.

 

.....

 

the white powdery thing clinging to the distributor is most probably aluminium oxide.
It easily forms in the presence of water or moisture and aluminium which has no protective coating - such as the distributor.
As long as the contact shoes do scratch through the oxide the electrical connection can work fine.
Mechanical removal with a brush usually does the trick. Inside the distributor maybe a shot of WD40. Electrical contact cleaner has shown to remove the stuff quite o.k.

I have seen that corrosion on quite some vehicles usually parked outside. My Blazer has no such corrosion on a 11 year old distributor but is always parked in a heated garage.

 

Thanks, 401, My Blazer doesn't know what a heated garage looks like, It is always parked outside for all four seasons. Right now it is covered with fall leaves.I am going to try the WD-40 treatment on the CMP and hope it works. I got sidelined by a water pump failure which now takes top priority. I have a new,not reman., NAPA water pump and thermostat and the rented 'clutch fan removal' kit and wish I had a heated garage to do this new project. No problem....unless it rains.