L 79 Valve Cover Opinion

[Frank C.]

I am attaching pictures of the valve covers from my April built 66 L79 SN: 20080.
Are these replacements or could they be original to the car?
I also do not see evidence of the casting flaw discussed in the JG.

Thanks

Frank

IMG_1906.jpgIMG_1901.jpgIMG_1902.jpgIMG_1903.jpg

[Joe L.]

Re: L 79 Valve Cover Opinion

I am attaching pictures of the valve covers from my April built 66 L79 SN: 20080.
Are these replacements or could they be original to the car?
I also do not see evidence of the casting flaw discussed in the JG.

Thanks

Frank

[ATTACH=CONFIG]44435[/ATTACH][ATTACH=CONFIG]44436[/ATTACH][ATTACH=CONFIG]44437[/ATTACH][ATTACH=CONFIG]44438[/ATTACH]

Frank-----


One could never say with absolute certainty but I think they're original to the car.

[Ray G.]

Re: L 79 Valve Cover Opinion

Hello Frank;
What Joe said.
my .02

[Frank C.]

Re: L 79 Valve Cover Opinion

Understood,

As long as these are not re productions, I will restore and use.
Thanks for the help.

Frank

[Morris R.]

Re: L 79 Valve Cover Opinion

i am attaching pictures of the valve covers from my april built 66 l79 sn: 20080.
Are these replacements or could they be original to the car?
I also do not see evidence of the casting flaw discussed in the jg.

Thanks

frank

[ATTACH=CONFIG]44435[/ATTACH][ATTACH=CONFIG]44436[/ATTACH][ATTACH=CONFIG]44437[/ATTACH][ATTACH=CONFIG]44438[/ATTACH]

they look to be originals, now if you were to be looking for period correctness then they are the wrong ones for your car. You need the flaw on your vavle covers to be correct. They started around vin #17,000 showing up with the flaw. If you are not concern with correctness keep them , they are in good shape. On page 92 in the jg you will find some information.

[Frank C.]

Re: L 79 Valve Cover Opinion

Morris,

Thanks. part of my question was could these be original to my car. I have no reason to beilieve they are not. The archives indicate others with as late as early 67 cars have original valve covers with no casting flaws, or even one with/one without. I have discussed other anomilies I have found with my car here. My position is if there is reasonable evidence/argument to suggest these could be original to the car, I will restore, and reinstall. I am just the current caretaker of this car, and not concerned about chasing points.

Frank

[Edward J.]

Re: L 79 Valve Cover Opinion

Frank, I have read some other post about the flawed 66 valve covers, I believe that the die cracking was a slow progress. so it could be that some of the earlier 66 cars after VIN 17000 show only minor flaws, being your car was 3000 cars after,Maybe the flaw(s) may only be small. There is many posts in the archives.

[Morris R.]

Re: L 79 Valve Cover Opinion

morris,

thanks. Part of my question was could these be original to my car. I have no reason to beilieve they are not. The archives indicate others with as late as early 67 cars have original valve covers with no casting flaws, or even one with/one without. I have discussed other anomilies i have found with my car here. My position is if there is reasonable evidence/argument to suggest these could be original to the car, i will restore, and reinstall. I am just the current caretaker of this car, and not concerned about chasing points.

Frank

hi frank,
there will be always reasonable evidence/argument for almost everything, thats why we have judges or in this case jg (ncrs) in determining what is more likely to be correct. You will never know for sure if they are originals to that car, all the archives will state different things and thats not to say your car came with those valve covers or it didn't. The bottom line frank if you are satisfy with your valve covers who cares if they are correct or not for that car as long as you are happy. Enjoy your ride! Have a great week

[Joe C.]

Re: L 79 Valve Cover Opinion

Understood,

As long as these are not re productions, I will restore and use.
Thanks for the help.

Frank

They currently have the proper surface finish, and I'd be VERY careful about "restoring" them. That finish can NOT be replicated without special re-skinning equipment, so any abrasive or chemical treatment will result in your having to spend a good deal of money on having them professionally reskinned.

It appears that, like MANY of them, yours may have porosity issues, or, may have been repaired or cemented on the inside. If it were me, I'd lightly clean them with mild aluminum polish, like Nevr Dull wadding. Install them, and if any leaks show up, abrade on the inside and cover the area with steel mesh embedded in JB Weld or other purpose formulated metal epoxy.

[John D.]

Re: L 79 Valve Cover Opinion

Seen I have seen my Corvette valve covers than I care to remember let me make a comment.
By April 66 one might expect a major flaw on the "Inside" of the valve cover. Meaning a rather pronunced sign of a crack., Not just a hint of a crack in the seam on the inside but one that you would not need glasses to see.

Meanwhile Frank the major crack and the unprofessional repair to it means the owner would not want to spend a lot of money in having this cover refinished. Replacement would be in order. John

[Henry J.]

Re: L 79 Valve Cover Opinion

Frank:

My April-built 66 L79 has the original valve covers and they do not exhibit a casting flaw.

[Joe L.]

Re: L 79 Valve Cover Opinion

All-----


For a part like these valve covers, I don't see how any sort of "precise" date can be established as to when a certain feature ended or began. GM plants, including engine plants, did not "rotate their stock" on a "first in, first out" type of basis. It was more like "last in, first out". So, older stock might languish for awhile and then be drawn out when the stock got lower. The same sort of thing might have occurred at the component manufacturing plants, too.

One other thing that's always troubled me: I realize that most of the evidence we have would point to the fact that only a single mold existed for every one of these valve covers ever cast. That seems strange to me, though. Even though this valve cover was a relatively low volume piece, it would just seem like there would have been more than one mold if only for manufacturing efficiency.

[Michael M.]

Re: L 79 Valve Cover Opinion

Hi guys,

I have a late March built 66 L79 #17178. I have one valve cover with and one without the casting flaw. They certainly appear to be original parts, but who knows if they were original to this car. They also look identical to each other at first glance, except for the crack, but I never took the time to check every little mark on the inside to see if they may have come from the same mold. That's something I will check out next time I have them off (if I remember to). My guess would be that there was more than one mold. They had to make close to 16,000 valve covers for 66 L79 production alone.

Mike

[Morris R.]

Re: L 79 Valve Cover Opinion

all-----


for a part like these valve covers, i don't see how any sort of "precise" date can be established as to when a certain feature ended or began. Gm plants, including engine plants, did not "rotate their stock" on a "first in, first out" type of basis. It was more like "last in, first out". So, older stock might languish for awhile and then be drawn out when the stock got lower. The same sort of thing might have occurred at the component manufacturing plants, too.

One other thing that's always troubled me: I realize that most of the evidence we have would point to the fact that only a single mold existed for every one of these valve covers ever cast. That seems strange to me, though. Even though this valve cover was a relatively low volume piece, it would just seem like there would have been more than one mold if only for manufacturing efficiency.

good point joe who really knows what went on 50 years ago. Have a great week.