[wheelspin]

Mike,

It's your call on buying new plates or cleaning up the existing pieces. As you observed, the indentations on the one plate (Dremel/emory paper will clean those up) will keep both throttle plates from closing as will the crud around their outer diameters. Maintain the locations and relationships of the plates (up/down side, front/rear) if you choose to remove them. If you remove the plates, first Dremel the staked end of the retaining screws (purchase new screws), being very careful to not slip and damage the shaft or bores.

I would chuck up a small wire brush or Scotchbrite and power clean the bulk of the crud off, finishing with hand-held brushes and Scotchbrite. As in all restoration projects, you have the choice to use new parts (when available), or elbow grease to refurbish the existing parts. My trips (looked like yours when received) have the original un-bushed shafts, throttle plates, and linkages with repoped fuel lines and Jon's carb kits as the only "new" parts.

Les

[mikediaz]

Thanks for the update wheelspin-
Perhaps I didn't mention this in my last post - I did remove the butterflies already to clean up the whole thing. Kept them in correct order to where they came from (won't fit anywhere near well any other way)

I didn't have to dremel the retaining screws at all to get them off. Although I have read (which agrees with what you said) that these screws are usually 'peened' and require such an operation to remove the plates. I guess someone already did it before. :-\

You're right on the new parts vs fixing old parts and I would like to fix as many of these old parts while ensuring a quality result so i will go out and buy some emory paper to lightly deburr the edges of the blades and see how well it closes then. (I'll do my best to maintain that slight angle I notice each blade has on its rim)

I'll also use the emory to lightly remove any excess scale areas on the bore.

If that's not enough then I'll look into getting new blades.

Thanks again -- all suggestions welcome

mike

[mikediaz]

Part 1 of this post:

Talked to Jon today aka carbking at The Carburetor Shop - Very nice guy!! Very helpful and very pleasant to speak too! If his parts are half as nice as he is this thing should turn out great.

So here's the update -
We tried to identify what the center carb is / was from since it has that weird casting number meantioned earlier in the thread. It's almost certainly not from a Pontiac () but the good news is that since the bowl casting indicates the bowl bores are 1-1/4 inch the carb should work for the application!! (applause)
But now he told me to get my hands on an orrifice drill to see what size the holes are on the idle tubes of the center carb's venturi cluster.

If the holes are not .032" (what they should be for the '65 389 application I'm gonna put them to work for) then I need to get them to that size with the orifice drill.

I don't know anyone around here with an orifice drill but I do know of some shops up the road and I believe one was some sort of machine shop which I bet will be more than overqualified to check a simple orifice size (and possibly enlarge it to .032).

Very glad I made that phone call to Jon @ the carb shop. Seems like a very good guy. I'll let you all know when I find out what size it is.





Part 2 of this post-
I noticed that on the end of the center carb's throttle shaft where it's suppsoed to hook on to the linkage, it appears as if the throttle shaft is either broken or (hopefully) missing a screw that holds the linkage to it. Please someone help me to determine if it's broken or not.

First picture shows the end of the throttle shaft in question.
2nd pic is a 2nd view of it from another angle.

3rd pic is the hole on the linkage attached to the center carb's choke-activating arm that I think should hook on to the throttle. It fits the suspect throttle shaft end perfectly but I figured I'd ask here. If anyone has a pic of their center carb's linkage in general PLEASE post it here. Let me know what you guys think

[Carl A]

My 65, hope you can get a screw there! looks like yours has been ripped off you could braze it ?The choke does not get attached to the arm the screw hits it on the lever .# 2 choke on #3 off

[mikediaz]

Pitts - thanks for the tip, I've heard about this a while back and have considered doing it but I'm not sure if I want to do that. I wonder if I should mess with pontiac's original design.. on the other hand it almost undoubtedly would do some good so maybe I will do it. I'll tackle that idea when I get to it so please stay tuned pitts!

Carl A-
Very interesting pics. Thanks so much for taking the time to take and post those pics they will come in handy!.

After seeing them I fiddled with my choke lever's screw and arm (the same piece as is shown on your first picture, with the big screw holding it down). And I got it to what the previous person to use this setup had it at so that the accel linkage would correctly(?) activate the choke.

HOWEVER- it seems my throttle shaft linkage is perhaps a self-made one?? It doesn't seem to allow full throttle because the link itself is so long that it hits the manifold just before wide open throttle. This doesn't allow it to fully open the choke valve or the throttle valves. Very close to it but just not totally (again about 20-40 degrees from full possible travel of both choke and throttle). <pic states at 45 degrees but i don't think it's quite that much. the throttle valves inside are almost full open when the link hits manifold>

Unless anyone has heard of Pontiac using two different types of linkage on the center carb's throttle shaft, I'd assume the best thing would be for me to buy a spare piece. With that in mind?:
ANYONE HAVE A SPARE LINK ON THE END OF THEIR CENTER CARB'S THROTTLE?

I sure hope someone here has it or else I will have to go to the wilderness that is eBay to hunt it down. Talking to Jon today on the phone he said that they don't reproduce or sell those, they sell the throttle shaft itself, but expect the buyer to provide their own end link.

I'll post a few pics with this msg showing my current end link at closed throttle, and at max throttle [As limited by the link's own dimensions]. The pics show where it hits the manifold.

If anyone has this end link piece please let me know. I'll be very interested in buying it from ya!

[mikediaz]

I hate to post this again but I just wanted to de-burry it from the last post:

ANYONE HAVE A SPARE LINK ON THE END OF THEIR CENTER CARB'S THROTTLE? thanks all

[Carl A]

Your arm is upside down.Does your end link? fit on the stub of the throttle shaft get it brazed!!!Or a new throttle shaft with a screw mount! One question is your car a 4sp?

[mikediaz]

WOW how did I miss that one! Thanks carl!! ... I guess i'd rather feel like a boob than go out and buy a part i already have

OK I flipped mine around. What had happened was, some previous owner (not the guy i bought it from- he hadn't touched it since he got it years ago, but perhaps the guy who sold it to him?) must have thrown the center's linkage together at the last second for the sale.

Had to separate the two parts of the end link and put them on right.

Thanks a LOT Carl A!!

Next round of questions:
Your choke valve (the big one on top of airhorn) llooks liek it is naturally completely open, wheras mine seems to be spring loaded to close shut when the throttle is closed.... could the spring be positioned incorrectly on the inside? Thanks again!!

[Carl A]

The last pic is from my files of tri/powers,as for the choke question a expert will probably have a answer for you,But what I know, it drop's open quite freely.the spring doesn't open it, but someone will correct me if I'm wrong!

[mikediaz]

Thanks again.
Yup someone please chime in on whether my choke valve is supposed to be closed all the time or what... it opens easily as Carl A mentioned that it should, it's just that wiith pedal not pushed down it would seem that the choke valve would shut the carb's air horn and that it would require lots of throttle angle to get it to open even somewhat via the linkage . Any ideas??


Also - my throttle end link on the center carb does fit onto the 'broken' throttle shaft end stub. I don't think it will be a problem getting it welded together with just a smidge of metal.

[mikediaz]

Mini-update. Been swamped with work. Haven't slept since Monday night from working and it's still going on now.

Anyways - the update is I just placed my order for the rebuild kit. I paid the extra price for the deluxe kit which includes a few more odds and ends and I figured it couldn't hurt. Should expect the kit to come in early next week. By that time I should be relaxing on spring break with my family and will have plent of time to get to work on the 3 boys.

There- I'll only have 56k so my posts will have to diminish as it's just hard to live on 56k but I think i'll make some time to post major updates and pics.

Anyone have any more notes regarding the choke and whether it's normally open or closed on tthe carbs? Mine stays shut until it gets partially opened with the throttle linkage arm but maybe a spring was put on in the wrong direction or something inside..
thanks!
Mike

[mikediaz]

Just to keep this threa fresh while I wait for my rebuild kits i figured I'd post how my intake manifold looks like.
This isn't the same shown in the other pics on this tread I bought this one off ebay a few months ago and painted it nice. What do you all think?

[Carl A]

Hey its backwards.LOL-- Good start , whats your plans on the carb body's

[mikediaz]

Hey Carl - thanks for the reply / interest!

The carb rebuild kits should come in circa Tuesdayish but till then I plan to just clean up all the carbs real well.

I measured the center carb's idle air tubes with an orifice drill set a teacher of mine has and they are the right size (.032" for a 389). (yay!!) So Right now its just cleaning / then rebuilding.

The teacher who let me use his tools (System Dynamics is the class if anyone knows what that is ;-P ) has done some carb rebuilding before (nothing too serrious) and gave me the name of a good carb cleaner to use. He said it's called Berryman's carb cleaner. Sold in big buckets like most carb parts cleaner. He told me it was really sick stuff and that I should wear lots of hand and eye protection and that its so strong-smelling he likes to put the carb part in there, seal up the berryman's bucket, then put that bucket into a 2nd bucket that's air tight when sealed.

Anyone use this stuff? Is it so hard core that I should be afraid of using it? It sounds like potent stuff. He said to let the venturi (or whatever part I wanna clean) soak in there for a few days then pul it out and immediately spray it down with some regular carb cleaning spray (b-12 chemtool or whatever) and then to immediately hose all the passages with compressed air before any gunk has a chance to resettle. Sounds like a good plan if I can get my hands on the stuff and as long as I'm safe with it.

Who thinks its a good or bad idea to use it? I'm assuming if its good enough for the venturi then it should be good enough for the carb body (bowl, cover, throttle body / shaft). All comments welcome and accepted.
mike

p.s. any of these posts may be my last for about a week (see my last post for why) but if all goes well I should be posting pics of my rebuilt carbs then. After that I just gotta get fuel lines, a throttle return spring and that clip on the end which the throttle return spring goes to.. oh and get that throttle shaft brazed to its end link too. I wouldn't say it's all 'coming together' just yet but the plan is set and the knowledge is getting there : )

[wheelspin]

Your teacher is referring to a two level carb cleaner (cleaning solution under a anti-evaporation "milky" solution) that is no longer produced (although Berryman obviously still exists) as I mentioned in my first post. If you find some that has not "eaten" it's way out of it's container; buy it and use it, as it produces nice clean parts! It will ruin plastic and rubber parts.

On your choke question; provided your linkages are correctly assembled, the choke closes when cold (and pulls the fast idle cam up to the high idle position), and opens when the engine provides suffcient heat to relax the thermal coil and allow engine vacuum to pull it open.

Les

[mikediaz]

what grease is best for throttle shaft? I'm assuming a light coat of some synthetic brake caliper grease should do nicely since they don't need much grease anyways and this should last for a long time in that environment.

[wheelspin]

Do NOT lube any of the carb shafts or linkage pivots, as it attracts dirt (all manuals stress this). Also, any lube inside the carb will be quickly washed away by the presence of fuel/fuel vapors.

Les

[mikediaz]

Check. Thx for the update! Some neighbor is leaking some free wireless internet so I may get to post a few things afterall. Couldn't find anything but a huge 5-gal bucket of berryman cleaner at 89 bucks!! I've got a few more places to hit up tomorrow else I'll just soak the parts in the GUNK version for a few days instead... The things probably aren't so terrible dirty that they NEED the hard berryman' stuff.

-???-
question - is it ok to soak just about all of the car ipeces in the cleaner? Including bowls and tops and throttle bodies. I would take all the pieces appart before doing so.

[mikediaz]

Hey everyone.! Waiting on those rebuild kits to come in today or tomorrow and still cleaning up the center carb and the messier part of the rear carb (front carb still untouched).

I got the Berryman dip and used it to clean up my rear carb's throttle body (did a nice job) and the venturi clusters of rear and center carb are soaking in there as we speak (will leave them in there until I'm ready for reassembly - probably tomorrow).

I had 2 questions though-

1)
Is my power valve supposed to move freely into and out of the cover it's a part of? It cleaned up easy enough (spring got destroyed in the clean up of course). But it doesn't move at all (in out whatever). I've never seen one so I don't know how it's supposed to operate.

2)how do I 'peen' a new throttle screw so that it never wiggles out of the blade and into my intake? I think that's the word 'they' (some web site) used when describing it. I figured I would just use a drop of the red threadlocker on it
but since the time to reassemble the throttle shaft is a coming I figured I'd ask here. Thanks!!
-mike

here's a pic of the powervalve:

[carbking]

The power valve is located in the bowl, and a new one is in the repair kit.

The power valve actuator is located in the airhorn, and the piston should move freely in and out for maybe 1/4 inch. The spring is absolutely essential to making the actuator work.

DO NOT REPEAT DO NOT USE RED LOCTITE!!!!!!!!!!!!!!!!!!!!!!!!! Use blue instead.

Jon.