Offenhauser intake

Yankee Transplant · Feb 21, 2015

OK I have an offenhauser intake and a quadrajet carb ,,, I dumped a little gas down in the carb to get it to fire up for the first time and gas leaked out between the base gasket and manifold... I got a new gasket and same thing happens ,,,do I have to get a adapter plate for this set up ?

Willowbilly3 · Feb 21, 2015

Sounds like it.

Old Iron · Feb 21, 2015

I first have to ask, are you sure it came from between the gasket and didn't run out the butterfly shafts?
Quadrajets are notorious for the shafts wearing out.

Yankee Transplant · Feb 21, 2015

old iron im not 100% on that but it looked like it come from left front ahead of butter flys .... it has a skip in it so Im not sure if its sucking air or I have some valves to tight .. I figure if I get an adapter plate (which I havnt found yet ) that would fix the leak and eliminate that as the skip .. It didnt leak when It was running , just when I dumped the gas down it ..

Yankee Transplant · Feb 21, 2015

it was running down on this bolt

Old Iron · Feb 21, 2015

It's almost impossible to get a Holley to seal up on a Quadrajet intake and vise versa
It most likely is dripping off the shaft when you pour it into the carb.
Here's the adapter to use
Trans Adapt 2034

sgtpontiac · Feb 21, 2015

Quadrajets have those metering well plugs in the bottom...

between the base plate and the housing....prone to leakage....they have a sponge rubber gasket of sorts in most Qjet rebuild kits...but I've always epoxied them when I rebuilt them....never had a leak again....they are soldered in from GM...never hold ....Think that might be your fuel source...

Willowbilly3 · Feb 22, 2015

If it runs, you should easily be able to determine if it has a vacuum leak. Just get 3-4 feet of vacuum hose, listen in one end and place the other end at area suspected of leaking.

I have a little different theory on those well plugs. Back in the 70s they had us all convinced we need to epoxy them on every build because the float bowls were draining down. Come to find out, it was leaking back down the fuel line and they put the little check ball in the fuel filter and cured it. I've probably rebuilt a couple hundred since then and never epoxied another one and afaik, never had a problem with one leaking.

Yankee Transplant · Feb 22, 2015

I got an adapter plate it started up and run ruff ... didnt leak any more gas ... I also adjusted the valves again ,, I think the ruff run was just as much the valves to tight as the vacuum leak .. got the valves adjusted ,, and it runs alot better but still got some bugs to work out.. I'll tinker with it more tomorrow . as long as its warm like it was today

Think it got to 73* today

21willys · Feb 22, 2015

Start it up and spray around with some wd40 or something. If it's sucking air it will let ya know cause it's gonna effect how it runs.

sgtpontiac · Feb 22, 2015

Never saw one that wasn't wet when I opened it up..

Willowbilly3 said:
If it runs, you should easily be able to determine if it has a vacuum leak. Just get 3-4 feet of vacuum hose, listen in one end and place the other end at area suspected of leaking.

I have a little different theory on those well plugs. Back in the 70s they had us all convinced we need to epoxy them on every build because the float bowls were draining down. Come to find out, it was leaking back down the fuel line and they put the little check ball in the fuel filter and cured it. I've probably rebuilt a couple hundred since then and never epoxied another one and afaik, never had a problem with one leaking.

If it was a running car.....No bull that they leaked....check valve cured hard start but those wells leaked all the time...at least in my experience...I never rebuilt one without sealing them..even if it wasn't damp with fuel....but again, that was me....glad you had better luck than most....I didn't take a chance

Bamamav · Feb 22, 2015

Throw that quadrajet away and get you a Holley Street Avenger or a Edelbrock carb. Or even one of those Summit Racing carbs. All are better than a worn out quadrajet.

Old Iron · Feb 23, 2015

^^^^^^^^^^^^^^X2^^^^^^^^^^^^^^^^^^^

26Troadster · Feb 23, 2015

besides without a adapter the back barrels will never open.

Offenhauser intake

Help Support Rat Rods Rule:

Yankee Transplant

He started out with nothing, he still has most of

Willowbilly3

A real tin magnet

Old Iron

Well-known member

Yankee Transplant

He started out with nothing, he still has most of

Yankee Transplant

He started out with nothing, he still has most of

Old Iron

Well-known member

sgtpontiac

Older, Wiser and Still Buildin'

Willowbilly3

A real tin magnet

Yankee Transplant

He started out with nothing, he still has most of

21willys

Well-known member

sgtpontiac

Older, Wiser and Still Buildin'

Bamamav

Well-known member

Old Iron

Well-known member

26Troadster

Well-known member

Similar threads

Latest posts

Offenhauser intake

Help Support Rat Rods Rule:

He started out with nothing, he still has most of

A *real* tin magnet

Well-known member

He started out with nothing, he still has most of

He started out with nothing, he still has most of

Well-known member

Older, Wiser and Still Buildin'

A *real* tin magnet

He started out with nothing, he still has most of

Well-known member

Older, Wiser and Still Buildin'

Well-known member

Well-known member

Well-known member

Similar threads

Join the conversation!

Join today and get all the highlights of this community direct to your inbox. It's FREE!

A real tin magnet

A real tin magnet