Hitman's Pontiac Trans Am Forum

Classifieds => Parts Wanted => Topic started by: Jefe on March 27, 2020, 06:46:19 PM

Title: 79 403 t-stat housing type1
Post by: Jefe on March 27, 2020, 06:46:19 PM
Hey everyone.
Iím new to this site, been reading lots of good tech here though for months. I am currently restoring our 79 Formula and am in need of a thermostat housing. I believe itís designated as type 1, ( cast part #547083) it is almost vertical to keep the upper hose behind the alternator. The bypass neck on mine was completely deteriorated. I suppose if I canít find one in good shape, I can always buy the other style, cut it apart to get the bypass tube out and braze that into my original housing. Anyone every tried that?
Title: Re: 79 403 t-stat housing type1
Post by: Wallington on March 28, 2020, 06:25:23 AM
Most of the 79's with 403 used the regular housing #409037 and a different top radiator hose, and it fit like rubbish and looked just as bad. The better early housing is 77-78 Firebird specific with Olds so hard to find as you've seen. There was a NOS one on ebay a few weeks ago, but listed for money it wasn't worth also.

No, the pipe has been cast into it so there's no cutting it out to reuse. You'd still have to cut off the pipe and reattach with an inserted tube for strength before welding up. I repaired one by tig welding a few pinholes but otherwise not worth playing with. Depending on where the corrosion is you could fit an earlier Oldsmobile rubber J-hose as a sleeve over the tube curve, not just the end gap. They do still turn up, in various conditions, not always described at thermostat housing, water neck is common, rarely mention part numbers either.
Title: Re: 79 403 t-stat housing type1
Post by: Jefe on March 28, 2020, 11:13:42 AM
Thanks for the reply Aus78formula. I was able to remove the remnants of the pipe from my water neck, hence the idea of cutting the new water neck away from the pipe. Do you recall how the part was listed on eBay? Might go and look at it. 78 has always been my favorite of the firebirds. Years ago I had a 78 DKM T/A, #127. Sure do miss that car. This car, the 79 Formula, has been in the family since it was new. My step Dad ordered it. From mid 1991 until January of 2019, it was sitting outside, next the garage at our place in northern AZ. Iíd post some pics, but not sure how to. I tried to attach a pic of the water neck in the original post and was told the file is too large,?
Title: Re: 79 403 t-stat housing type1
Post by: Wallington on March 28, 2020, 10:41:54 PM
https://www.ebay.com/itm/NOS-GM-1977-79-Pontiac-Trans-AM-6-6-Liter-Water-Outlet-Thermostat-Housing-/223735185613?nma=true&si=5thhBmJKPL7n4r05eJOd1XKjGYI%253D&orig_cvip=true&nordt=true&rt=nc&_trksid=p2047675.l2557


This is the earlier version bypass hose that may be able to save a pitted water neck.

https://www.ebay.com/itm/OLDSMOBILE-WATER-OUTLET-THERMOSTAT-HOUSING-BYPASS-HOSE-330-350-403-400-425-455/133286439594?hash=item1f087daaaa:g:rTAAAOSwG-1WzSsK

Files can't be added to the forum, they must be hosted elsewhere and the link inserted.
Title: Re: 79 403 t-stat housing type1
Post by: Jefe on March 28, 2020, 11:49:37 PM
Thanks for the link. Iíll reach out to see if itís still available and if so, make a reasonable offer. Since I already removed the old pipe from the neck, I might tap the hole  where it went and install a short nipple. Then it would accept the older style hose.
Thanks for all the help and ideas.
Title: Re: 79 403 t-stat housing type1
Post by: RENOVATIONS on April 12, 2020, 09:20:33 PM
I finally found mine (I knew it was buried somewhere in the garage) and it is the  early type (part# 547083).
I blasted it and gave it a quick shot of primer...and noticed a small crack in the housing where the tube is inserted.

I don't know if the cast could be welded or maybe filled with JB Steel...just throwing it out as an option if you still haven't found one.
Title: Re: 79 403 t-stat housing type1
Post by: Jefe on April 12, 2020, 09:54:57 PM
Found one on eBay but itís not in quite as nice of condition as was stated. Can you send a pic of the crack? BTW, is this site very active anymore? After signing up and looking around a bit, it seems most posts are older.?
Title: Re: 79 403 t-stat housing type1
Post by: RENOVATIONS on April 13, 2020, 12:14:12 AM
Sure, I'll take some pix tomorrow and email them to you.

Not that active anymore...Facebook, etc seem to have taken most people's attention elsewhere.
There is however still a great deal of information to be found on this site.
Title: Re: 79 403 t-stat housing type1
Post by: Jefe on April 13, 2020, 12:25:48 AM
Iíve seen a great deal of great info here. Hard to believe there can be a single source (ie Facebook) that could even compare to the wealth of knowledge found on this board. Is the original creator even still around? Seems the store is closed permanently. Nonetheless, I appreciate you keeping this alive for those of us who are seeking info on these great cars of yesteryear. Any thoughts on finding the plastic bits for the wire looms/retainers on the 403? Iíd like to share some pics of the build that Iím doing, whatís the best way to go about doing that?
Thanks again.
Jeff
Title: Re: 79 403 t-stat housing type1
Post by: Wallington on April 13, 2020, 12:32:52 AM
Facebook is only for one post, one answer then gone. Wait for someone to ask the same question the next day. Here, the answer can be found and info saved. Problem is, many treat it the same way, ask a question and never return to read all the replies. The same people reply now on here compared to when it was active, there were just more questions being asked.
Title: Re: 79 403 t-stat housing type1
Post by: Jefe on April 13, 2020, 12:45:00 AM
Sounds about right. I tried FB, canít seem like to wrap my head around it though.
Title: Re: 79 403 t-stat housing type1
Post by: RENOVATIONS on April 13, 2020, 12:55:23 AM
I'm a member of several car groups on Facebook and the amount of misinformation posted is frightening.
You may have to search a bit here but at least  the information you find here is much more reliable.

Hitman is still around...just taking some personal time off.
Title: Re: 79 403 t-stat housing type1
Post by: Jefe on April 13, 2020, 01:14:06 AM
Out of all of my searches for info for the build of this car, Iíve found more info on this site than any other. Hence, my reason for joining. Thanks guys, for sticking around and keeping it active. Who knows, maybe someday I can even help someone else out.
Title: Re: 79 403 t-stat housing type1
Post by: RENOVATIONS on April 13, 2020, 01:18:24 AM
You're helping out already...like Aus said, it's nice just to see a new member actually check back and reply to their posts.
Title: Re: 79 403 t-stat housing type1
Post by: RENOVATIONS on April 13, 2020, 01:38:47 AM
Realized that since I'm still up, I might as well send you the pictures now...and I won't worry about forgetting to do it tomorrow.
Sending you an email now.
Title: Re: 79 403 t-stat housing type1
Post by: Wallington on July 02, 2021, 12:25:57 AM
Old post, reminded as saw a good used 403 water neck on ebay a few days ago for 77-78 version.

Reno....did you check if that 'crack' isn't just an untidy casting join, or not in the centre?
Title: Re: 79 403 t-stat housing type1
Post by: RENOVATIONS on July 02, 2021, 07:26:33 AM
It was a pretty shallow crack so I just V'd it out and filled it with JB Steel....good as new!

Probably should put it out there for sale (along with a ton of other parts I don't need) at some point