1967 427 3x2 linkage problems "help"

[Pete NCRS # 30998]

Corvette 1967 427/400 3x2 4spd No Air/PS/PB or TI

Hi Guys & Gals, I recently sent sent my tri power cards to Woodruff to have them completely rebulit and finished to like new factory specs. I left the accelerator linkage special bolt and teflon sleeve and lock nut on the center card (for the secondary carbs linkage) When I received the cards last week those parts werew not there. I call and they were lost. I ordered a new linkage kit from Corvette Central. I have spent hours on it and still cannot figure out how to install the linkage. Any help or pics would be gratly apreciated.

Also I noticed that on the center card the throttle butterflies do not open all the way like the front and back cards do. Is that normal?

I have a few links below of the linkage and carbs>

Also I have a pic of my water pump, it has the correct date and part # but it has studs instead of bolts. Is that correct or not?

Link to pic here>
Thanks in advance for any help!!

Pete
NCRS Member # 30998

[Wayne P.]

Re: 1967 427 3x2 linkage problems "help"

The brass bolt and self locking nut go thru the slot in the center carb and the holes in the rods.The bent ends go in the arms on the end carbs with the clips.

[Pete NCRS # 30998]

Re: 1967 427 3x2 linkage problems "help"

Hi Wayne, I have installed it through the center carb slot and when I push the throttle it just slides up and down and does not work the secondary carbs.I tighten the lock nut all the way but it still slides up and down in the slot. Anyone haa a close up pic?

I put the front carb linkage rod in the back of the slot and the rear linkage rod in the front of the long slot, is that correct?

Thanks,
Pete

[Clem Z.]

the linkage is only to "CLOSE" the end carbs

not to open them. the vacuum diaphrams do that

[Pete NCRS # 30998]

Re: the linkage is only to "CLOSE" the end carbs

Ok, so they should be in the closed position when installing the linkage. Where on the center carb should the linkage be mounted at, towards the top, center or bottom? I guess it is meant to be loose and move freely up and down too, right? I just remember when I took the old set up apart it was all the way on the top and very tight and the 2 linkage rods were mounted together side beside, I guess that was not correct for the kit from Corvette central had diferent parts. Sorry for my stupidity and been slow on this issue.

If someone has a close up pic I would love to see it.

Thanks in advance for the help.
Pete

[Clem Z.]

Re: the linkage is only to "CLOSE" the end carbs

it is very hard to discribe. your best bet is to find a picture of the linkage and i am sure someone here has one they can post.

[Wayne M.]

There's a Service News Bulletin on this ...

Chevrolet Service News, December 1967. Clem is correct about the linkage function being only to CLOSE the secondaries, but you'll need more than one picture.

I can post this procedure if you can't get your hands on the bulletin. Apparently the adjustment procedure does not appear in the 1967 or '68 Service Manual, and GM had to advise dealers via Chev Service News.

[Donald W.]

Re: 1967 427 3x2 linkage problems "help"

FYI

[Pete NCRS # 30998]

Re: 1967 427 3x2 linkage problems "help"

Hi Don, thanks but the pic will not load up for some reason.

[Pete NCRS # 30998]

Re: There's a Service News Bulletin on this ...

Hi Wayne, if you could post it or email me it would help me alot.

Thanks in advance,
Pete
pjs1inc@aol.com

[Mark L.]

427 3X2 linkage

Pete, I've just gone through the same question and have some info for you. I'll caution you that I looked at a Bowtie car in Park City and I can't say for sure the linkage was as delivered from the General.
The bolt head is on the inside and one plastic washer is against the head. Next is the plastic sleeve which fits in the slot. Next is the other plastic washer on the other side of the slot. Next is the front linkage followed by the back linkage and the nut. Adjust so that both front and rear carb are fully closed at idle.

[Wayne M.]

Here's theService News Bulletin on this ...

Pete -- the bolt (clevis)/washer/sleeve/linkage arrangement in the center carb long slot is as Mark has described.

Here's the GM published procedure for secondary linkage adjustments:

1. Warm up engine until choke in open position.

2. Disconnect closing rod ends from each secondary carb; set idle to specs; shut engine.

3. With clevis pin bottomed in primary carb throttle (long) slot [my note: you'll have to hold it there with left hand], adjust REAR secondary carb closing rod so that it falls short of entering the secondary throttle lever hole, by 1/2 rod diameter. Install rod and secure with special clip [my note: to install rod, allow clevis to rise a bit in the long slot].

4. Next adjust FORWARD secondary carb closing rod so that it just enters the forward secondary throttle lever hole. Install rod and secure with special clip.

5. When the adjustment is complete, the clevis pin will be at a point just ABOVE the bottom of the primary throttle slot, thus insuring that there is freedom in the linkage and a positive secondary throttle closure.

[Pete NCRS # 30998]

Re: 427 3X2 linkage

Thanks, sounds correct. I received a couple of pics and both were set up that way.

thanks,
Pete