1981-c3 Gas Cap Correct

[Tom R.]

Re: 1981-c3 Gas Cap Correct

The gas cap used for 1978-81 Corvettes in PRODUCTION was GM #559346, although I won't say that every 1978-81 Corvette received this cap since it's possible others were also used. It was a cap with a METAL top with an "ear" (i.e. raised finger-hold). The top was zinc plated with a chromate (i.e. "gold") overplate. The perimeter of the cap had small "serrations" as an additional hand-hold. The metal was stamped "unleaded fuel" and there may or may not have been additional stampings.

Joe, The 559346 cap we look for is dome shaped but no ear (finger-hold) if I understand what you're describing. Earlier caps 76 or so, had the ear.

Let me also say that I regard it as POSSIBLE that some 1980-81 Corvettes MAY have originally been equipped with cap GM #22503147. GM #22503147 is a metal cap but it has no "ears". It has more of a "dome" shape than the cap with the "ears". It is stamped with the 22503147 part number and "NDH". I have no PRODUCTION documentation to support this, but I still believe it's a possibility.

Joe & Michael

As a 78-82 judge I pay attention to the gas cap out of curiosity and the various types to caps used during this period (as well as 75-77).

Last year at Carlisle I picked up a 22503147 for a few bucks. It is identical to the 559346, dome shaped with the ratchet notches around the base and the number and NDH stamped in same location as that for the 559346 cap. I've got several 559346's as well.

The tech manual calls for the 22503147 for the 80 model year, but, as you've probably surmised, it does not get into the nuances of the point in production in which one cap style is phased in while another is phased out. What makes sense is what is point out above and that is one style was used at the St Louis plant while another was introduced at the BG plant.

[Tom H.]

Re: 1981-c3 Gas Cap Correct

Tom, Thanks for tking the tim on this subject. It helps for my quest of Gold at Bloomington. I live 15 miles from Pheasant run and I can not wait until June....Mike

Best of luck in your quest for gold !!

[Michael H.]

Re: 1981-c3 Gas Cap Correct

Joe, The 559346 cap we look for is dome shaped but no ear (finger-hold) if I understand what you're describing. Earlier caps 76 or so, had the ear.



Joe & Michael

As a 78-82 judge I pay attention to the gas cap out of curiosity and the various types to caps used during this period (as well as 75-77).

Last year at Carlisle I picked up a 22503147 for a few bucks. It is identical to the 559346, dome shaped with the ratchet notches around the base and the number and NDH stamped in same location as that for the 559346 cap. I've got several 559346's as well.

The tech manual calls for the 22503147 for the 80 model year, but, as you've probably surmised, it does not get into the nuances of the point in production in which one cap style is phased in while another is phased out. What makes sense is what is point out above and that is one style was used at the St Louis plant while another was introduced at the BG plant.

Thanks Tom, I will keep looking for the proper cap! Mike

[Michael H.]

Re: 1981-c3 Gas Cap Correct

Best of luck in your quest for gold !!

Thank You - Going to meet in next few weeks with Robin Winan - (Harmony Corvette) to help guide me. He does a great job.

[Terry M.]

Re: 1981-c3 Gas Cap Correct

I'm Lost On The Gas Cap. I Have Seen Stant G803 Brass Metal With Plastic Screw.....and A White Plastic Cap...and The Ac Delco Part I Purchased Was Black Plastic Cap??

At The Vette Fest I Saw A 1980 With The Brass Top And This Was A 1-owner Car.

Anyone Have A Photo?

[Tom R.]

Re: 1981-c3 Gas Cap Correct

"78/79 metal cad caps gold irradiate

Terry...did you mean for that finish to be irritate or iridite?

[Tom R.]

Re: 1981-c3 Gas Cap Correct

I think the noted authority had a lapse of recollection of course I've had lapses as well but than I'm not a noted authority . I'm posting images of 559346 cap with date code and the 22503147 with date code. I draw the conclusion that the year is the last digit, preceded by the production week. I've got a 1977 dated 559346 as well (326 7).

559346 with date code 172 9

559346finishside.jpg

559346dateside.jpg

And the 22503147 with date code 290 9

22503147finishside.jpg

22503147dateside.jpg

[Terry M.]

Re: 1981-c3 Gas Cap Correct

Terry...did you mean for that finish to be irritate or iridite?

Spell check gone wild -- or a Freudian slip

[Terry M.]

Re: 1981-c3 Gas Cap Correct

[QUOTE=Tom Russo (22903);398717]I think the noted authority had a lapse of recollection of course I've had lapses as well but than I'm not a noted authority . I'm posting images of 559346 cap with date code and the 22503147 with date code. I draw the conclusion that the year is the last digit, preceded by the production week. I've got a 1977 dated 559346 as well (326 7).

Well he didn’t get the link and question until late last night, and he pleaded fatigue when he responded. I am not so sure he intended me to post his response (one of the reasons I am keeping his name out of this) -- and given the hour I am sure it was off the top of his head. You will get the chance to debate it with him at some Regional or maybe even the National, if you bring up the subject during judging.

I wouldn't be opposed to making this discussion a part of the Advanced Judging School at one of the events, if we have enough examples on hand. It would have to be along the lines of a round table discussion, but with a modest amount of planning that could be accomplished.

I mostly wanted to get the date codes out there so it will be easier to separate the original from the replacements -- at least in some cases. I was a little disappointed he didn't get into "ear or no ear," but given the circumstances I got what I asked for.

[Michael H.]

Re: 1981-c3 Gas Cap Correct

I'm glad you took the time to get involved - my Journeyman when apprenticing was named Terry Connole - he taught me not to skip details. That was over 30-years ago. Thanks Mike

[Tom R.]

Re: 1981-c3 Gas Cap Correct

I wouldn't be opposed to making this discussion a part of the Advanced Judging School at one of the events, if we have enough examples on hand. It would have to be along the lines of a round table discussion, but with a modest amount of planning that could be accomplished.

We've had several (well maybe a few) discussions in the last month or two and I suspect after this last flurry of posts, we've about covered the 75-82 restricted gas cap. So we probably have photos which means powerpoint and with a few examples to supplement, it would be an interesting discussion.

[Terry M.]

Re: 1981-c3 Gas Cap Correct

I don't do PowerPoint, but if someone put the presentation together, I would be willing to try to work out the logistics with the Regional or National sponsors. Sounds like room & projector. We would probably need a little more than gas caps -- although no one wants to miss the chance to look at real Corvettes. John Woods used to do a nice preso, but an hour is about the butt limit, as he used to say. I am not as skilled a speaker as he was, but I am willing to moderate.

[Tom R.]

Re: 1981-c3 Gas Cap Correct

I don't do PowerPoint, but if someone put the presentation together, I would be willing to try to work out the logistics with the Regional or National sponsors. Sounds like room & projector. We would probably need a little more than gas caps -- although no one wants to miss the chance to look at real Corvettes. John Woods used to do a nice preso, but an hour is about the butt limit, as he used to say. I am not as skilled a speaker as he was, but I am willing to moderate.

It's started.

Who would you be wanting to attract? Late model C3 or all of C3. I could post my pics of the 1978 Muncie and get the C2 guys in there to educate them that not all side covers with a reverse shaft are saginaws!

[Terry M.]

[Michael H.]

Re: 1981-c3 Gas Cap Correct

Looks like I stirred the pot....Please keep me in the loop....Mike