Powdercoating valve covers

pablon2

Registered User
Question about powder coating (or not) the valve covers. I brought mine in to have the exterior coated and the guy was hesitant to do it b/c of the rubber-like seal on the PCV ductwork on the underside. He figured the 400deg bake process would melt it. What are my options? Have people powder coated them successfully?
 
darkstar_one said:
exactly what are you talking about.... the grommet? the rubber thing on the oil filler thing...


I'm talking about "the PCV ductwork on the underside." If you look inside the cover you'll see there is a rubber-like seal (almost like a silicon bead) between the housing and the sheet metal that sits under the PCV hole. I'm not talking about the grommets, which took all of 30 secs to remove.
 
I can tell you that when they sandblast your valve covers for powdercoat they will start to disintergrate......Magnesium doesnt hold up well to powdercoating...I did however get mine done
 
I got mine done a while ago and all I did was pull the grommet's and baffles out before hand. I don't remember seeing anything else under there. Maybe the 94-95's are different.
 
I haven't seen any sealant uunder the baffle before, so maybe someone did that before you got the car? RTV is good for 350+ degrees so it should be fine anyways. Depending on the RTV used it could be good for 500+. I have powdercoated MANY valve covers with out any issues at all. As for sandblasting yeah thats not the greatest, bead blasting is much more effective on the magnesium.
 
SCme94 said:
I got mine done a while ago and all I did was pull the grommet's and baffles out before hand. I don't remember seeing anything else under there. Maybe the 94-95's are different.


Okay, I guess my "ductwork" = your "baffles". Question then, how did you put the baffles back and get them sealed to the housing (inside of valve cover)? My concern is if I R&R the baffles, I may have an oil leak and increased blow-by.
 
you don't need sealant, just bolt them back on and you'll be fine, if you are really concerned then use the high temp RTV to seal it.
 
V6Sprout said:
I haven't seen any sealant uunder the baffle before, so maybe someone did that before you got the car? RTV is good for 350+ degrees so it should be fine anyways. Depending on the RTV used it could be good for 500+. I have powdercoated MANY valve covers with out any issues at all. As for sandblasting yeah thats not the greatest, bead blasting is much more effective on the magnesium.


The bead I am seeing is tannish in color and runs down the sides of the inside of the cover where the baffle meets the cover's wall. I'd post a pic right now, but they are at the powdercoaters. Do most place that sand blast also bead blast? Thanks.
 
not all places will bead blast, they should be able to since I believe they use the same guun just a different media. If not get them to use the finest sand they can when sandblasting, there are different grades of sand they can use.
 
even teh bead blasting will eat away at the magnesium//Its more of a cosmetic thing. I wanted mine perfectly smooth. Nothing a buildup of powdre didnt solve..Just be careful
 
DamonSlowpokeBaumann said:
even teh bead blasting will eat away at the magnesium//Its more of a cosmetic thing. I wanted mine perfectly smooth. Nothing a buildup of powdre didnt solve..Just be careful


I'm gonna go ahead and have the guy powder coat them. I'll tell him to be careful and to not put a hole in the cover, just to get the paint off.:D I'd rather have a small percentage of the OEM paint not be removed if it means the cover won't be ruined. Besides, we see so little of the covers' surface area once everything is reinstalled, so I don't need the job to be immaculate.
 
Increase BLOW-BY?

pablon2 said:
My concern is if I R&R the baffles, I may have an oil leak and increased blow-by.
Ummmmm, the baffle in the valve cover has nothing to do with the piston rings, which is where blow by comes from. R&R'ing the VC baffle will not increse combustion gasses leaking past the piston rings.

68COUGAR
 
68COUGAR said:
Ummmmm, the baffle in the valve cover has nothing to do with the piston rings, which is where blow by comes from. R&R'ing the VC baffle will not increse combustion gasses leaking past the piston rings.

68COUGAR


Just something I heard. Why do they plumb the blow-by kits into the PCV line?
 
Oil Seperator kit?

pablon2 said:
Why do they plumb the blow-by kits into the PCV line?
I assume that you talking about the oil seperator kit for the PCV, Right? I've never heard of a "Blow-By Kit".

Positive Crankcase Ventilation. In the beginning it was used to evacuate gas fumes from the crank case. 12:1 compression was common on the street in those days, & with that much compression, some of the fuel/air mixture got past the rings & ended up in the crank case. One breather was open to the atmosphere. The other breather was plumbed to a vacuum source. When you decelerated (high vacuum), any fumes in the crank case would be pulled out & sucked into the engine & burned. It worked Great for sucking gas fumes out, but it also sucked oil mist from windage.

The oil seperator in the PCV system attempts keep any oil mist from getting sucked back through the supercharger & ending up in a puddle at the bottom of the I/C.

I don't believe that the oil mist hurts the supercharger in any way. However many SC Guys are concerned about the puddle of oil they find inside the I/C. I think they'd rather see the oil in the seperator than not see it in the I/C.

68COUGAR
 
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68COUGAR said:
I assume that you talking about the oil seperator kit for the PCV, Right? I've never heard of a "Blow-By Kit".


68COUGAR

Yes, I am talking about the oil seperator that is sold as a "blow-by" kit. Spinning-Wheels dot com had sold them for awhile.
 
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