Anyone running the United Motors vented distributor cap?

[PlayingWithTBI]

Distributors still make Ozone gas even in AZ.

Not if you inject Halon in it

Just kidding bud!

 

[Supercharged111]

^^^ - OR, move to AZ

Are you aware of how hot it gets there?

 

[L31MaxExpress]

Are you aware of how hot it gets there?

I think the heat index is often even hotter here with the humidity factored into it. 99-102F with 90% humidity and zero wind blows.

I just found a chart. It is sometimes nearly 100F at 1am here in the concrete jungle of DFW.

Now I realize why I have gotten good at making ac and cooling systems better.

You must be registered for see images attach

 

[Supercharged111]

I think the heat index is often even hotter here with the humidity factored into it. 99-102F with 90% humidity and zero wind blows.

I just found a chart. It is sometimes nearly 100F at 1am here in the concrete jungle of DFW.

Now I realize why I have gotten good at making ac and cooling systems better.

You must be registered for see images attach

Oh I'm aware, 2 states that would be appealing to me were it not for the fact it's as hot as the devil's taint in the dead of summer.

 

[454cid]

...The T goes into the hose for the factory a/c heater controls...

Most of us don't have that. Only the vehicles that have the coolant shutoff to the heater core would have that, amd most (all?) trucks don't have it.

 

[L31MaxExpress]

Most of us don't have that. Only the vehicles that have the coolant shutoff to the heater core would have that, amd most (all?) trucks don't have it.

Well then if its a vortec 4.3 or SBC, get the cap that twist on with the added hose barb. I assumed they all had it because my Van, a couple of Astros, both Tahoes and Suburbans I have had did. Otherwise tap into the 3/8" off the PCV. Point is to get engine vacuum to it, whatever that requires.

 

[L31MaxExpress]

Dorman 47026 has two hose barbs in addition to the PCV. Port for the AC, port for the distributor and a port for the PCV.

 

[Komet]

Man, in the past two days I've learned that my distributor is filling with ozone and the 048 ICM is stealing all my advance when I'm trying to make the last 2 horsepieces out past 3800rpm.

Not sure if my engine runs good anymore or I just have low standards.

 

[Rocket Surgeon]

Solve the problem basically for good, vacuum vent the thing. It is not hard, its cheap, and it works.

Materials

1/8"-27 NPT tap and 27/64" drill bit
2 x 1/8 NPT to 1/4" barb 90" brass or plastic fittings
3/16" or 1/4" fuel filter
3/16" or 1/4" check valve
3/16" or 1/4" hose splice
3/16" or 1/4" hose T
Dorman 47311
I used 3/16" vacuum hose so that everything fit very snuggly and did not require clamps.

Drill and tap the distributor base in a place that you can get the 90" nipples into and turn for install, I put them 180* apart and pointed the nipples the same orientation as the plug wires. If needed the nipple end can be slightly shortened. The T goes into the hose for the factory a/c heater controls, then the check valve so that engine vacuum pulls air from the distributor body but a back fire or fuel will not enter the distributor body, then the orifice, then the filter, then a hose to one of the barbs on the base. The second hose gets fresh air vented to it from the air intake system behind the air filter and in front of the throttle body. When the engine is running it continually pulls the ozone and moisture out of the distributor housing and replaces it with fresh, filtered air. Seal the factory screen if it is still there or use its opening for one of the barbs. I sealed the cap to the base with RTV as an added measure to keep moisture out. My aluminum base did not have a vent, which is why I set it up this way when I first installed it.

THIS IS FREAKIN AWESOME!!!!

Not sure about hvac vac controls on a truck.... but more to see and learn....


related distributor story:

Dealt with a SO's POS 99 4.3 Sierra. Discovered the oil had not been changed in years. I did a top end "overhaul", lifters and gaskets among other things... But the thing loved to eat distributor caps. Every few month or so it needed cleaned, and sometimes replaced. When humidity was high, it often had trouble starting. (note that apparently there is an issue with this application where A/C line condensate actually drips on the distributor???) It had two vents in the bottom, so I restricted them with steel wool or copper choreboys, and lightly RTVed the distributor in place. This made things much worse actually. I then ran 3/8" drill bit though both vents. Frequency of issues decreased but did not depart. remember years of no oil change? I think the issue is actually blowby on this one.

Your vacuum cleansing idea would have been excellent here.

 

[someotherguy]

THIS IS FREAKIN AWESOME!!!!

Not sure about hvac vac controls on a truck.... but more to see and learn....


related distributor story:

Dealt with a SO's POS 99 4.3 Sierra. Discovered the oil had not been changed in years. I did a top end "overhaul", lifters and gaskets among other things... But the thing loved to eat distributor caps. Every few month or so it needed cleaned, and sometimes replaced. When humidity was high, it often had trouble starting. (note that apparently there is an issue with this application where A/C line condensate actually drips on the distributor???) It had two vents in the bottom, so I restricted them with steel wool or copper choreboys, and lightly RTVed the distributor in place. This made things much worse actually. I then ran 3/8" drill bit though both vents. Frequency of issues decreased but did not depart. remember years of no oil change? I think the issue is actually blowby on this one.

Your vacuum cleansing idea would have been excellent here.

Like 454CID mentioned, the GMT400 pickups don't use any vacuum in their HVAC controls - all electronic. The exception would be that one heater control valve used on some of the SUV models. So if you want to use the vacuum method you may need to choose a different source.

The GM TSB about the distributor vents seems to only cover models other than 400's which is puzzling to me as I can't imagine they use a different distributor. Maybe there's some revision? Anyway, if there are still vent screens in the base of your Vortec distributor, pop 'em out and straight to the trash with them, and then be sure the vent holes are clear. The bulletin is GM TSB 03-06-04-041A by the way, and for whatever reason that one little bit of info doesn't just jump out at you when researching the subject. Here's mention of it by NAPA but they're using it to suggest buying their Echlin distributor cap which has brass instead of aluminum terminals. https://www.napaechlin.com/media/3137/ei002-05-gm-vortec-distributor-issue.pdf

TSB info aside, the vented cap offered by United seems like another way to achieve this.

Richard