Clearcoat on Intake DOES yellow!
Thread Starter
Le Mans Master
Joined: Feb 2000
Posts: 7,032
Likes: 2
From: Newburgh NY
Clearcoat on Intake DOES yellow!
About 4 years ago I detailed the engine and compartment on my 78 (Pic 1 below). The car has only been out on sunny days and only a total of maybe 6k miles since I completed it. I saw some yellowing a year or so ago. Finally bit the bullett yesterday and tore it down. I also have a slight hesitation/stumble and planned to rebuild the carb anyway. A good rainy weekend project. 
In the second pic, that's what it looked like from above yesterday. With the air cleaner and other junk in the way it didn't really look that bad. But then when you pull the junk out you begin to see what was really going on under there. It appears there may have been a slight leak under the carb (probably wasn't tight enough), the distributor had a little oil coming up through the gasket from underneath, and the EGR was spewing. Couldn't believe it looked this bad.
Also figured I'd redo the valve covers, change the thermostat and adjust the valves being I'm in there.
In the second pic, that's what it looked like from above yesterday. With the air cleaner and other junk in the way it didn't really look that bad. But then when you pull the junk out you begin to see what was really going on under there. It appears there may have been a slight leak under the carb (probably wasn't tight enough), the distributor had a little oil coming up through the gasket from underneath, and the EGR was spewing. Couldn't believe it looked this bad.
Also figured I'd redo the valve covers, change the thermostat and adjust the valves being I'm in there.
Le Mans Master
Joined: Mar 2004
Posts: 7,463
Likes: 1,485
From: Little Rock AR
Looks like the beginning of a beautiful frame-off 
That is how my '80 got garage jail a while back. Brought it in for a simple belt replacement that turned into a full engine overhaul!!!
It went like this...Those brackets needed some work, then the heads needed to come off for some work, then the bottom end - might as well pull that too since I have it down this far...look at that crank, needs a regrind... Oh WELL !
Your car looks great. Just don't go finding more stuff to do on it like I did.
-Mark.
That is how my '80 got garage jail a while back. Brought it in for a simple belt replacement that turned into a full engine overhaul!!!
It went like this...Those brackets needed some work, then the heads needed to come off for some work, then the bottom end - might as well pull that too since I have it down this far...look at that crank, needs a regrind... Oh WELL !
Your car looks great. Just don't go finding more stuff to do on it like I did.
-Mark.
Thread Starter
Le Mans Master
Joined: Feb 2000
Posts: 7,032
Likes: 2
From: Newburgh NY
Yep. Had spacer and both EGR gaskets on there as well as a gasket on the heat tube/vacuum chamber. The bolts were all tight too.
Got all new gaskets though. Will clean up the parts and reinstall and keep and eye on it.
Got all new gaskets though. Will clean up the parts and reinstall and keep and eye on it.
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Le Mans Master
Joined: Jan 2001
Posts: 6,938
Likes: 1
From: San Diego CA
I tried (on my old 77) every paint known to man to keep it silver and they all turned yellow. i sucummed to buying the polished Performer intake and never looked back. The 68 has a Torker 2 intake which someday I'll go back to a stock oramge Chevy intake and Q-Jet.
Le Mans Master
Joined: Mar 2004
Posts: 7,463
Likes: 1,485
From: Little Rock AR
I always hit manifolds with a very light dusting of dull aluminum high temp spray paint. Not enough to fill in the pores or make it noticeable. It seems to help. You have to have the can pretty far away to avoid any paint buildup. Several very light coats.
-Mark.
-Mark.
Instructor
Joined: Aug 2002
Posts: 231
Likes: 0
Originally Posted by Jughead
That's a shame. Wonder if Clear powdercoat would hold up.
