67 fuel sending unit leaking. Need help

[Ara G.]

Hey guys. Merry Christmas, happy holidays and happy new year. The sending unit on my 67 silver coupe is weeping gas from the sending unit. I tightened the nut by the electrical connection. It's the original sending unit. I researched in the archives and consensus was to get GM gasket, rubber o ring and deco authorized repro sending unit. However I can't find supplier with any GM gaskets or o rings. I checked my local Chevy dealer and he laughed....been discontinued for some time. Any help? Should I replace the sending unit as well as the leaking gasket? Any sources on GM o rings and gaskets? Thanks guys! Happy New Year!
Ara

[Roger P.]

Re: 67 fuel sending unit leaking. Need help

Hi Ara, I had a similar problem recently and replaced my sending unit with a Fargo Automotive repro unit (a broken repro unit was replaced with another repro unit about 5 years ago). Read my recent thread here: https://www.forums.ncrs.org/showthre...nding-Unit-Cam. If the leak is definitely from the original unit and not the O-ring, then you should contact John Wolf & Company. From what I have read in other threads, everyone has been very happy with their restoration work. AC Delco still sells fuel sending units for about 3 times the price of a repro unit, but it's made in China with all the other units. The Fargo unit is very good and is the closest thing to an original unit as confirmed by those who know more than me, but they are very hard - if not impossible - to find (I think they may be discontinued). Good luck and Happy New Year, Roger (50141)

[Roger P.]

Re: 67 fuel sending unit leaking. Need help

Also read this current thread regarding the new O-ring and cam lock: https://www.forums.ncrs.org/showthre...ng-Unit-Gasket

[Ara G.]

Re: 67 fuel sending unit leaking. Need help

Roger,
thanks for the reply. I saw your thread. I actually really think the leak is coming from the gasket and not the sending unit but while I'm there I thought I would replace the sending unit...now that the tank is empty and all...and the partial tank sticker is there. So I may order new tank so I can save the sticker. Not sure if I can find a Fargo unit. Will try. But there's gotta be a unit that works...meaning sending unit and gasket. Any alternatives out there that will work if I can't find a Fargo? Also what about the gasket? Not finding the GM one available...any help appreciated. Thanks and Happy New Year! Ara

[Larry M.]

Re: 67 fuel sending unit leaking. Need help

Roger,
thanks for the reply. I saw your thread. I actually really think the leak is coming from the gasket and not the sending unit but while I'm there I thought I would replace the sending unit...now that the tank is empty and all...and the partial tank sticker is there. So I may order new tank so I can save the sticker. Not sure if I can find a Fargo unit. Will try. But there's gotta be a unit that works...meaning sending unit and gasket. Any alternatives out there that will work if I can't find a Fargo? Also what about the gasket? Not finding the GM one available...any help appreciated. Thanks and Happy New Year! Ara

Ara:

For the o-ring:

1. Call Dr Rebuild and request their GM o-ring # 3825206. Pat Boyd purchased two just yesterday. Cost about $12 each.
2. Try this link http://www.buickfarm.net/index.php?o...655&Itemid=101
3. Tell your GM parts guy to get on the computer and do a search for GM # 3825206 within the GM USA parts network. There should be a number of dealers with old stock still on the shelf. I have used this locating service successfully many times in the past.
4. Buy a repro from a good, reliable source and then mike the o-ring to make certain that it's thickness is the same as original. Not certain what this is anymore, but maybe Pat or Roger or one of the other forum guys will comment with the correct thickness. I installed my last one in my car about a year ago, so I don't have one on the shelf to measure. Sorry.

Larry

[Roger P.]

Re: 67 fuel sending unit leaking. Need help

Ara, my TDB research has convinced me that, if you have the original sending unit, you should send it to John Wolf & Co. so it can be restored. I can help you find a Fargo unit, but why replace an otherwise good functioning original with a POS repro unit? I wish my original unit was still with the car... but at least I was lucky to find a Fargo unit after a lot of searching. Send your unit our for restoration (I believe it runs about $150.00) and buy a $12.00 GM NOS O-ring from Dr. Rebuild (you only need one). Make sure to soak the O-ring in engine oil overnight before installing it. Use your original locking cam as the repros also have issues like the repro O-rings. With an original restored sending unit, NOS O-ring, and original locking cam, you will be in excellent shape for many, many years. If your tank is in good shape, I would suggest that you take high-definition photos of the tank sticker and cover it in-place on the tank with a heavy-duty clear plastic cover that is taped around the perimeter with weather-resistant tape (something like clear duct tape). I saw a thread on the TDB or the CF where someone did that and I thought it was an excellent idea. This way you will have documentation for your records while maintaining the original tank and sticker. Let us know what you decide to do and how it turns out. Best, Roger (50141)

[Ara G.]

Re: 67 fuel sending unit leaking. Need help

Thanks so much for the replies! I am going to get the gasket ( thanks Larry) and send the sending unit out for rebuild.... I will try to post pics of the tank sticker when I drop the tank. I appreciate all the replies ...happy new year! Ara

[John D.]

Re: 67 fuel sending unit leaking. Need help

GM part number 3825206 was used from 1963-1981 and is discontinued in the catalog since 11/7/2011.

[Ara G.]

Re: 67 fuel sending unit leaking. Need help

Hey guys - update....I found an original 66 tank from a member and removed my original tank with it's partial tank sticker still on to preserve. It's gorgeous. Also, the stampings are still on the side of the tank so if anyone wants some pictures of an original stamping I would be happy to send you some pics. So I sourced 2 NOS fuel sending unit O ring gaskets. I soaked the ring in engine oil overnight and installed the rebuilt original fuel sending unit in the 66 original tank last night. No leaks present (but sore back). I added about 15 gallons of fuel to make sure no leaks. I will check tonight, but wanted to post an update and to thank all for the insight and advice. Nothing fits like original. I even was able to salvage the original tanks anti squeak pads from my original tank and reuse them on the newly acquired tank. Used a metal spackle knife and it came off nice with no rips. thanks again for all the help....ARA

[Larry M.]

Re: 67 fuel sending unit leaking. Need help

Ara:

Appreciate the update/finale. Glad all worked out.

Larry

[Roger P.]

Re: 67 fuel sending unit leaking. Need help

Hi Ara. I'm glad your project worked out well with a positive result... another task crossed off the list!! :-) Best regards, Roger

[Joe L.]

Re: 67 fuel sending unit leaking. Need help

GM part number 3825206 was used from 1963-1981 and is discontinued in the catalog since 11/7/2011.

John------


As far as Corvettes go, the 3825206 was used from 1963 through 1974. From 1975 onward Corvettes used a fuel sending and pick-up unit mounted on the top of the tank. However, the 3825206 may have been used for non-Corvette applications through 1981.