Exhaust headers for 225 V6; Alu pipes leading to carb

[OliY]

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Hey guys, Great to be on here and hopefully get some help with my CJ3b rebuild.

I’m slowly trying to restore my CJ3b with Dauntless Buick 225 V6 225 V6. It has GM 1375908 exhaust headers. The passenger side header has (had) 2 x 1/4 inch alu pipes leading from the header carb (2 jet Rochester) but one broke off and the other has a gaping hole in it.
Presumably these help with vacuum or suction???

What are these pipes called? I’ve looked online for replacement headers which include these pipes (as the pipes don’t seem to be removable from the exhaust) but nowhere seems to stock the headers with these alu pipes.

Does anyone have any bright ideas?

Ps be warned that as an amateur mechanic there may be a few more dumb posts from me yet!!

 

[OliY]

I'm new to the forum and have uploaded some photos to show what I mean but when clicking insert image I get new screen showing my images but no way of adding them to this message.

Anyone have any clues on that too?

 

[mriplaybass]

Welcome to the forum!
When you reply to a post or start one, click on the attachment icon (paper clip) locate the file on your computer and select it. Pretty simple. Or, if you have your photos stored on an image hosting server that allows 3rd party hosting, click the image below the "undo" icon and copy and paste the url.
As far as your exhaust, not quite sure what aluminum tubes you are talking about. I have a 225 Dauntless Buick 225 V6 in a 67, and a 1974 231 odd fire (uses the same exhaust manifold) in a 59 CJ5 , but I don't have the tubes you are talking about. The 59 has fender well headers, so if they ever existed, they are gone now. Post some pictures. Like they say, "a picture is worth 1000 words. If everything is aluminum, TIG welding is always an option.

 

[mtnwhlr]

I can click on your images and see them. Those are not headers but stock exhaust manifolds. As far as the tubes I think they are to heat the intake. I would like to see the other end where they go.

 

[OliY]

Hey Guys, Thanks for the replies.

Mr I play bass, most of the icons on the reply screen don't work for me (aren't clickable) which is weird so I've uploaded a couple more photos to my gallery.

I;ve been doing more research tonight and found that the service manual http://www.myedocs.com/onlinefiles/jeep/manuals/53-71 Jeep CJ & DJ SM.pdf
Says that these pipes are 'air riser pipes" which take hot air up through the intake manifold.

However, when I found the jeep the 2 air riser pipes were connected to the carb (2 jet rochester). I've added a photos to show where the pipes run and where they were connected to the carb.

The service manual Ive been following doesn't list the particular carb I have and so there's no mention of these riser tubes attaching. Doesn't it seem odd that exhaust hot air riser tubes would connect to the carb?

The point of these tubes is to take excess hot air air away form the manifild as theres a heat activated close- valve between the right side manifold and exhaust pipe. I think the idea is that the valve is automatically shut when the manifold is cold and opens as it heats up. Any excess air goes through these pipes upward, and in my case connects to the carb.

Hope you guys can see the photos i've added so it makes more sense.

Let me know if you've got any good suggestions.

Thanks again

Oli

 

[Colorado Yeti]

Can you post a picture?

 

[mtnwhlr]

After looking at your new pics the one is for the chock. It heats up the coil in the black plastic piece and opens up the chock then when you shut it off the coil cools and closes the chock. I don't know know about the other one.

 

[mtnwhlr]

See if this helps you in posting pics. look up in the top right corner of the page do you see a circle with a line across it next to a heart? If so click on the circle and a box will pop up and then click on unblock content. Then you should be able to click on insert an image from your gallery and select the image. Hope this helps.

 

[OliY]

Hey Mtnwhlr,

The pic thing worked great!! thanks a bunch, that should make things alot easier from now on!!

And thanks for the tips on the chock... You mean the chock inside the carb or do you mean the coil valve between the manifold and exhaust pipe?

For CO Yeti.... hope fully you can see these pics now....

 

[mtnwhlr]

And thanks for the tips on the chock... You mean the chock inside the carb or do you mean the coil valve between the manifold and exhaust pipe?

The chock in the carb.

 

[OliY]

Thanks for all the help here.

I think I've gotten to the bottom of the problem.

The riser tubes were connected to the choke in order to create additional heat and a quicker start without the use of the manual choke (which was also attached to my rochester 2GC carb). My wifes grandfather presumably added this system to help with cold winter days in the rockies.

That being said the riser tubes from the manifold were basically defunct when I found the jeep as one had a huge hole in it and the other was disconnected to the carb. The jeep still ran once I had tipped some fuel into the top of the carb and the whole thing had heated up.
Whats more is that there was no coil inside the black plastic cap on the choke side of the carb so it;s now clear the whole heat riser system wasn't working.

So, rather than try and replace or find a new manifold and riser tubes i'll just cap of the old riser tube outlets and put a purely manual carb on top as I don't intend to use the jeep in the coldest winter months.

Can anyone recommend a decent 2jet rochester replacement carb?

I found these....

https://www.summitracing.com/search...e/v6/engine-size/3-7l-225/engine-family/gm-v6 but any personal recommendations would be awesome!

Thanks to all.

Oli

 

[mriplaybass]

You can also install and electric automatic choke. Installs the same way the choke cap for a manual choke does, except you run a "key on hot" 12v wire to it instead of a cable. https://www.amazon.com/Standard-Motor-Products-CV196-Thermostat/dp/B000C7UPLU/ref=sr_1_fkmr1_1?s=automotive&ie=UTF8&qid=1521559441&sr=1-1-fkmr1&keywords=jeep+cj7+electric+choke+conversion+kit
This is just an example. You would have to find the right one for your carb.

 

[JeffP]

No, no, no.... did you resolve this yet?