Quadrajet and Tquad questions for Mike M.

[SOAZBINDER]

If I wasnt already bald, I would have pulled my hair out by now. I dont think I have ever had my rear handed to me so bad before as these tomco crap so called rebuilt carbs have.

Trying to get my 79 Scout II rallye with 345,727 dialed in since it has became my primary mode of transportation. I am on my
3rd tomco quadrajet. Originally I ran the thermoquad carb until it started running real bad. I would really like to run this carb again except I dont have the confidence to open it up and rebuild it. Scout is all original with all smog intact..and I like to keep it that way.

Since I didnt have the confidence I took the easy road and bought a tomco rebuild quadrajet. 1st ran really well. Mileage and power were excellent. Then, I loaned the carb to a friend who ran it on his Scout and unbknown to him or me, he developed a crud/rust problem and plugged my quadrajet up. Twice we took it apart to fix it and it still wont run right. So, I exchanged it for another tomco quadrajet. It ran worse. Exchanged a 3rd time and this one runs ok, but I am having serious hot start problems, mileage sucks, power sucks, and just not happy all the way around. I wish I hadnt of loaned my original carb. Also..its really hot down here in az right now so I dont know if some of my problem is the oxygenated fuel boiling?

Which brings me to my questions. I have read your thermoquad info on here till my eyes bleed. I am an efi guy and still am not confident enough to venture into the original thermoquad....do you offer a rebuild/modifying service to where I could send you my (preferably) thermoquad or quadrajet and you can work your magic on one (or both) for me?

Also, could you tell me what this screw does in the picture of the quadrajet I posted below. The one in the middle of the carb just up and to the right of the pcv port?

I hope to get the thermoquad dialed in on the rallye and get the quadrajet running good enough to put on another Scout I drive less often.

Thanks Mike for your help.

Jared

 

[Michael Mayben]

Jared!!

I gave your's and paul's contact information to at least two folks at the Binder Bee as a source for parts in your part of the world! What a coincidence???

Anyway...I'm not the one to talk about q-jets! My track record with 'em suks! I rebuild 'em when really pressed (done two just last month for my neighbor's sons who both have 'em on chev-powered inboard boats), but I really don't have enough experience with 'em to be a resource!

As for thermoquads, my track record is about 50/50. The last few I've done should have been nice...we do have the proper fix for the plastic fuel bowl leakage. But the units I've done recently were really rotten in the upper bowl cover where all the metering stuff is located, those were badly corroded from water exposure and simply have metal removed through corrosion internally which can't be repaired. I finally had to give up on 'em and in one case, refund a customers investment.

However...out of the blue I received a call from bruce who owns "carburetors unlimited" in peoria (phoenix metro), az. I fixed up bruce with some parts he was desperate over for some Holley 2300 mixers and we jawwed for hours. Bruce is an old fart like me and has a small shop doing carbs onna one-on-one basis for local rodders and off-road folks. Here is his webpage with contact info:

high performance carburetor rejetting rebuilding tuning by carburetors unlimited

Bruce's main product is quadrajets for off-road use! After our telephone visit, I knew he was the real deal and not at all a bullshitter. Since then I've referred other ihon members to bruce and all have reported a pleasant experience.

So rather than waste your time, I'd give bruce a call, tell him how ya found him and see if he can make your mixer play nice!

Those tomco carbs must have been sitting inna warehouse for years, they went bankrupt in 2005 iirc. All their crap is usually "converted" from some original core to be a generic replacement, and never correct for any one application. That is why we always prefer to rebuild a customer's original mixer instead of just supplying an in-house rebuilt with a core that May not be original since it came to us as a rebuilt from somewhere else.

That quadra in your pic is based upon a chev core as seen by the fuel inlet location. And the screw you are asking about is part of a much later model "idle air bypass" system (I think but I'm not certain) and May not even be active if that carb was built out of mis-matched pieces. Bruce will know!

We hate to give up any potential business here at ihon, but I know you are a customer and supporter of our company and it's in our best interests (and yours!) to know when to punt! So kick the ball to bruce and let's see what happens...since you are in the phoenix area on occasion, maybe yawl can hookup face-to-face!

 

[SOAZBINDER]

Wow. Thanks Mike. I appreciate the referral on the parts. I am currently moving to a bigger shop and while im in the process of moving I intend to organize and try to inventory my collection a little better.

Thanks for the hook up on the carb guy. I will defianatly contact him and see what he can do for my carbs I have. Hopefully he is reasonably priced since I will most likely have more carbs to do in the future. Me and carbs just dont get along it seems. Might be from my more modern transportaion experience. Paul is pretty good with them, but he is moving to michigan and has been busy doing that...so he isnt around much anymore. See what happens when you meet a nice gal and get all twitterpated? Them dang women do nothing but cloud a mans judgement.


I was not aware that tomco went out of buisness. All the quadrajets I messed with were in a Holley reman. Box with tomco stickers, so ????? Who knows whats going on there? All I know is they were crap. These were sourced from the local checker. (csk auto, now o-riellys)

thanks for the info. Maybe someday I will make it back up to the wet country soon. I have been longing for it since my last oregon Scout rescue mission.

I will post back next week (im going to the cool country for the rest of the week to get outa this heat) with my experience with bruce.

Again, thank you.

Jared

 

[73scoutII]

jared!!

I gave your's and paul's contact information to at least two folks at the Binder Bee as a source for parts in your part of the world! What a coincidence???

Anyway...I'm not the one to talk about q-jets! My track record with 'em suks! I rebuild 'em when really pressed (done two just last month for my neighbor's sons who both have 'em on chev-powered inboard boats), but I really don't have enough experience with 'em to be a resource!

As for thermoquads, my track record is about 50/50. The last few I've done should have been nice...we do have the proper fix for the plastic fuel bowl leakage. But the units I've done recently were really rotten in the upper bowl cover where all the metering stuff is located, those were badly corroded from water exposure and simply have metal removed through corrosion internally which can't be repaired. I finally had to give up on 'em and in one case, refund a customers investment.

However...out of the blue I received a call from bruce who owns "carburetors unlimited" in peoria (phoenix metro), az. I fixed up bruce with some parts he was desperate over for some Holley 2300 mixers and we jawwed for hours. Bruce is an old fart like me and has a small shop doing carbs onna one-on-one basis for local rodders and off-road folks. Here is his webpage with contact info:

high*performance*carburetor*rejetting*rebuilding*tuning*by*carburetors*unlimited

Bruce's main product is quadrajets for off-road use! After our telephone visit, I knew he was the real deal and not at all a bullshitter. Since then I've referred other ihon members to bruce and all have reported a pleasant experience.

So rather than waste your time, I'd give bruce a call, tell him how ya found him and see if he can make your mixer play nice!

Those tomco carbs must have been sitting inna warehouse for years, they went bankrupt in 2005 iirc. All their crap is usually "converted" from some original core to be a generic replacement, and never correct for any one application. That is why we always prefer to rebuild a customer's original mixer instead of just supplying an in-house rebuilt with a core that May not be original since it came to us as a rebuilt from somewhere else.

That quadra in your pic is based upon a chev core as seen by the fuel inlet location. And the screw you are asking about is part of a much later model "idle air bypass" system (I think but I'm not certain) and May not even be active if that carb was built out of mis-matched pieces. Bruce will know!

We hate to give up any potential business here at ihon, but I know you are a customer and supporter of our company and it's in our best interests (and yours!) to know when to punt! So kick the ball to bruce and let's see what happens...since you are in the phoenix area on occasion, maybe yawl can hookup face-to-face!

Add me to the list. I will get back to you on bruce. I picked up an oem IH spreadbore mani today. Dropped it off for a good refresh at the local machine shop. After reading this thread I called up bruce (sorry Jeff) and bsed a bit before discussing a qj from him-- real nice guy . He is building me a custom setup with the automatic altitude adjusting 3rd jet and electronic choke. So when I'm up in the sierras I don't have to worry about adjusting anything for the altitude.

Just want to thank everyone on this site. I'm learning tons. I spend wayyyyy too much time reading things here..

ps - Mike have you heard about reversing these things (primaries in the back) to prevent problems on steep inclines? I have been doing a lot of research and heard a bit about this.

 

[Michael Mayben]

add me to the list. I will get back to you on bruce. I picked up an oem IH spreadbore mani today. Dropped it off for a good refresh at the local machine shop. After reading this thread I called up bruce (sorry Jeff) and bsed a bit before discussing a qj from him-- real nice guy . He is building me a custom setup with the automatic altitude adjusting 3rd jet and electronic choke. So when I'm up in the sierras I don't have to worry about adjusting anything for the altitude.

Just want to thank everyone on this site. I'm learning tons. I spend wayyyyy too much time reading things here..

ps - Mike have you heard about reversing these things (primaries in the back) to prevent problems on steep inclines? I have been doing a lot of research and heard a bit about this.

I think bruce does bizz just like we do here at ihon, that makes him a good dude in my book and we certainly don't mind helping our customers with referrals for stuff we can't provide or do. So let us know how this comes out.

As for reversing the carb/manifold, in the case of a spreadbore thermoquad or rochester q-jet, what you are really doing is flopping the pivot point of the float/needle/seat system. In my opinion, the float system design in both of those carbs is really crap...but it worked ok for emissions applications. They just have a very small actual fuel volume/reservoir so that at an extreme angle, the metering orifices will not be completely immersed in liquid on a continuous basis.

 

[Duly]

Mr. Mayben,
I just wanted to follow up my experience with bruce and my q-jet rebuild. He did an excellent job and the truck runs perfect. I didn't have enough time to tune it correctly at 7,000-10,000 feet while in Colorado, but now back in texas it starts, runs, idles perfectly all I need to do in the morning is set the choke, turn the key and she's ready to go. I am still trying to get the choke pull-off set just right, but that will come with trial and error.

Thank you again for all your help,
duly

 

[Michael Mayben]

mr. Mayben,
I just wanted to follow up my experience with bruce and my q-jet rebuild. He did an excellent job and the truck runs perfect. I didn't have enough time to tune it correctly at 7,000-10,000 feet while in Colorado, but now back in texas it starts, runs, idles perfectly all I need to do in the morning is set the choke, turn the key and she's ready to go. I am still trying to get the choke pull-off set just right, but that will come with trial and error.

Thank you again for all your help,
duly

Thanks for the feedback regarding bruce and his products!

 

[FatSmitty]

X2 on dealing with bruce. Top notch job. I gave bruce my specs over the phone and when the carb showed up, all I had to do is bolt it up, and figure out the linkages and it fired right up. Set my timing and she purrs like a kitten. Bruce was real good with questions after the sale too. Bruce is a real good guy and was patient with all my dumb questions and lack of knowledge. Would definitely recommend him. Only downside to dealing with bruce, is that he is a one man show and very busy so it May take a bit, but it will be done right.