Topic: UL-631 Bulb Fit -

[jwc66k]

This is a common bulb used as an under dash courtesy lamp. Mine burned out and the replacement would not fit, it would not slide in deep enough for the pins to grab. I tried this same bulb on sockets of three different cars, a 65 and two 66's. It would not slide in any of them. I tried a second bulb with the same negative results. I examined the original and replacement bulbs and there is a difference in construction. The replacement bulb has a flare in the metal base where it holds the glass bulb, the burned out one does not have that flare which seems to allow it to slide in deeper. The original was a GE, the replacement is made by Wagner. On my latest parts order I asked if this flare was on the bulbs in stock. The guy on the phone got one from stock and verified it was a Wagner and it did have a flare. There is a possibility that the two bulbs I tried were from a bad batch, but has anybody else had this fit problem?
Jim

[carlite65]

yes. just ran into this on a 66 conv. last week. i lightly filed the flare and got the bulb to fit.

[ruppstang]

yes. just ran into this on a 66 conv. last week. i lightly filed the flare and got the bulb to fit.

Same here did the same thing.

[jwc66k]

I brought this fit problem to NPD's (California store) attention today, again, with the additional comments and "fixes" noted from this forum. The only way this or any other problem part that is sold on the open market can be corrected is to bring the problem to the attention of the sellers.
Jim

[Scott302]

Well this is a new one.
We literally sell hundreds of these 631 bulbs each year.  No one has ever come to us to tell us they had an issue with them.  I realize these bulbs fit a wide variety of applications but you would think someone would have mentioned it before.
An interesting issue.  I first tried the bulb in a reproduction dash harness and it fit perfectly.  I then tried it in my original harness 65 and 66 cars.  Fit was tight in the 65 (barely and not without a few tries and force) and I could not get it into my 66.  Figure that... a repro part (wire harness) thats fits another part better than the original!  The parts that I see causing the issue are the flange on the bulb and the "fingers" that retain the housing on the socket.  There is a very fine line that determines if the current bulb will fit in the socket or not.  The interference between the fingers and the flange being the determining factor.  Unfortunately I do not have a solution for this.  One of you has already mentioned that you filed the bulb flange.  The other option may be to tweak the "fingers".  From what my Philips rep has told me there are only a few manufacturers of miniature bulbs that the big name suppliers buy from and they are all in China.  I checked other suppliers and compared our Wagner bulb to Philips and Sylvania and they all have the flange.  I will mention this to the reps I know but I am but a needle in the haystack that is the automotive miniature bulb market.  I do not have a lot of influence here but I will try.  If any of you know of a different 631 bulb supplier that does not have the flange I am all ears.  Drop me an email.
Regards,

[ruppstang]

It has not been a big thing to deal with but what I appreciate is the fact that you are making a effort to fix the problem.
Thanks Marty Rupp

[jwc66k]

Well, I guess I stirred it up again. I talked with the California NPD people and they did convey the problem up the chain of command. I like that, and NPD does have that kind of good reputation. I'll try the filing down solution when I get some more 631 bulbs from NPD next week.
Jim 

[C5ZZ]

Just had the same problem with mine, I was able to come up with
a couple of good used GE bulbs but I believe if you bend the teeth
or little fingers back out of the way some it should provide enough
clearance to get the bulb in.

[Brian Conway]

I just bought a box of ten Wagner bulbs and discovered they won't fit the 65 car but do fit the 69. This is the correct bulb for the cars I am concerned with and at $2.00 plus per bulb don't think I should have to fiddle with them and hope they will work.  Has any one tried finding/buying the G.E. bulb ?  Is there a LED bulb that will work ?  Brian

[krelboyne]

Here are some more examples of vintage 631 bulbs. I think that TS is TungSol.

[midlife]

I just bought a box of ten Wagner bulbs and discovered they won't fit the 65 car but do fit the 69. This is the correct bulb for the cars I am concerned with and at $2.00 plus per bulb don't think I should have to fiddle with them and hope they will work.  Has any one tried finding/buying the G.E. bulb ?  Is there a LED bulb that will work ?  Brian

Where are they used on the 1965 Mustang?

[jwc66k]

Where are they used on the 1965 Mustang?

The two under dash courtesy lights, plus 64 and 66 thru 69. It has a Ford service part number of C3VY-13466-A.
Jim

[jwc66k]

This is a common bulb used as an under dash courtesy lamp. Mine burned out and the replacement would not fit, it would not slide in deep enough for the pins to grab. I tried this same bulb on sockets of three different cars, a 65 and two 66's. It would not slide in any of them. I tried a second bulb with the same negative results. I examined the original and replacement bulbs and there is a difference in construction. The replacement bulb has a flare in the metal base where it holds the glass bulb, the burned out one does not have that flare which seems to allow it to slide in deeper. The original was a GE, the replacement is made by Wagner. On my latest parts order I asked if this flare was on the bulbs in stock. The guy on the phone got one from stock and verified it was a Wagner and it did have a flare. There is a possibility that the two bulbs I tried were from a bad batch, but has anybody else had this fit problem?

It has been 8 years and this problem still exists.
Jim
I added the specifications for this bulb. Note that there is no outward flare of the metal base at the bulb. In effect, any bulbs that have this flare are not per spec.

[RoyceP]

I am having issues with the LED replacement for the 631 bulbs. The base is too short to fit in the original sockets. Original 631 bulbs fit and work fine. The base is about 1/16" taller than the chinese made modern replacements. Have not tried modern replacement 631 bulbs, sounds like perhaps someone tried to save some money in the wrong place again.