Checked the tech archives and the 97 social group and am having no luck. I need to rebush the carb base on my Ford 2100 and need to find bushings/info. I already have oversize shafts, any help would be great, thanks...
Dan, We do rebush and have a couple sizes of the br*** sleeves, however i need a size of the throttle shafts. Measure the shafts and let me know ....
If you have oversized shafts wouldn't you just ream the holes to the shaft size. Rebushing would allow you to use stock shafts.
Dan the oversized shafts are so that you don't have to rebush. Basicall they were made as a repair for a carb that the hole is egged. You ream the hole for clearance and insert the shaft. The proper clearance for the shaft is going to be noted somewhere on a spec sheet for the carb. If Bubba or someone has a bushing the correct size for the shaft and it were mine I would probably bush it from the start. More often than not you won't get the hole round and be a fit for the shaft anyway. So if you can't ream it to size and round for your shaft you can overcome that with the bushing.
I likely have the same tooling as Bubba and you'best let him rebush because the tool used to ream the existing holes is double sized and fed thru both sets of holes and reams 'backwards' so to speak, then you take it apart and ream going back the other way. This is done specificall so that one hole is aligned to the other hole. A standard industrial reamer would work only from outside in. It can't p*** thru because of the center between the venturii. Send it to Bubba.
Sorry cant help in this case, our tooling is either 5/16 or 3/8s . We are set up for throttle body fuel injection bodies and some carbs. Our finished sizes are .316,.314 and .375,.377 and .378 Like someone said above the oversized shafts should have fixed your problem....
Google Vintage Speed and click on Stromberg carb parts on thier website. That may help get the info you need. I just ordered two Rochester secondary bases from them and they seem to have alot of nice stuff for vintage engines and intake systems, everything from air cleaners to complete fuel systems.
checked vintage speed and they dont seem to carry just the bushings... put the dial indicator on the shaft in question and it has .009" slop, I am guessing that is probably too much?? found a place in Canada that sells all the tooling to do the job but they only have bigger sizes as well... if my oversize shaft is .281, what do I want the i.d. of the bushing to be (how much clearance is good)? i.e. maybe my new oversize shaft might take up enough of the slop in the old bushings??
Check with J&L Industries... They just might have a .282" or .283" reamer in stock or they'll order one up for ya....
Dan, heres a little tip if the new shaft is a little tight in the new bushings. I liked to do this generally after I had re-bushed the old Harley drag carbs. Put a lite coat of FINE valve grinding compound on the shaft, and spin the shaft SLOWLY with a drill motor while working the shaft back and forth as much as possible. Like honing a cylinder almost. Clean and repeat until you have the desired " feel " you are satisfied with. This method really gives you a precise honed fit, but besure to clean all the parts EXTRA carefully before final ***embly. I am not a 97 or 94 expert and dont claim to be, if there is not enough area to grab the shaft with a drill motor, you should find a piece of drill rod the correct dimension and hone the new bushings that way. Or you can weld/braze a small extension onto the old shaft if you re-bushed to the standard dimension. Doing this just help to asure you there wont be any high spots that might cause the shaft to stick WFO at the wrong time. If the bushings and the shaft are dissimiliar metals, they will expand and contract at diffrent rates. More work than most feel is needed, but if you follow my post's, I'm just a real pain in the *** for perfection.
I babbitt mine. If it strong enough for my banger motor it will last a long time as a carb bushing. Drill out the shaft bore and pour around the shaft.
The best solution is here: http://www.stromberg-97.com/stromberg_parts_online.htm Strombergs have bushings stock...the right bushing also has a "hat" shape that retains the linkage, the left protrudes slightly from the throttle body casing. A tap or an EZ-out will help extract them. Then go to the new stock size shaft...there is even a possibility the original is good. Oddly, the shaft often wears less than the bushing even though seemingly softer. Oversize throttle shaft is a significant restriction...reducing it through slabbing has far more effect on flow than you would expect. I have only seen flow tests on Q Jets, but on those, which have bigger bores and smaller shaft than a 97, the shaft is the most effective modifiable part in increasing flow! Reaming out is also a serious endeavor, as the oblonged hole will pull hand tools off axis and really fubar the fit of the throttle plates. When the bushings are a stock part that can be R&R'd there just is no reason to oversize.
^ The master has spoken. Dan I dunno if you've had a chance but check the tech links in my signature, but there's some helpful stuff there. I put oversize shafts in the four 94's on my Cadillac and for me I simply carefully used a 9/32 drill bit and i have to say the carbs work beautifully.
Just so I am clear on this, he's got 0.009" play in the shaft. If this is not acceptable, what is? This would be too tight, in my book, for a connecting rod side clearance. Would this not be at risk for binding when the Zinc carburetor body and steel shaft heat up and expand?
Some answers from a serious, heavy-duty Strombergista: Look at http://www.jalopyjournal.com/forum/showthread.php?t=209312&highlight=reamer+clearance Stock numbers, advice on tightening them a bit. Throttle body is iron, I think bushings are steel. The shaft is br***, so high expansion, but its placement isolates it a bit and of course it has air flow all the time.
I put the oversize shaft in the carb base and now have about .005 slop, thing is running quite a bit better now but not yet 100%...good point about the oversize shaft cutting down airflow, had never considered that... Bruce, that is a great resource, thanks - however would the stromberg shaft and bushings fit the ford carb base??
And another read: http://www.jalopyjournal.com/forum/showthread.php?t=233982&highlight=reamer+clearance The 94 is a different can of worms, since it has no bushings, but it would be just as easy to ream it out for some industrial-supply bushings as it would be to bodge it up for an oversize shaft. On the Stromberg...whyinhell do they even MAKE an oversize shaft for a carb that has replaceable bushings right from the factory?
On the Ford carb base...measure everything, hit some place like MSC and dig through the bushing pages. If you think too much clearance is hurting you at idle, an easy check is some grease smeared around each end of the shaft. This will temporarily cut off the unmetered airflow. You can still have bad idle, though, from bad fit of throttle plates due to general slop OR bad technique allowing drills and reamers to drift off course following the oval wear and so not fitting their bores properly. With multi carbs on small engines, you really need a good throttle plate fit to be able to control idle flow well enough.
In one of those links, the question is asked can this be done in a drill press. NO. Do not do this procedure in a drill press, 1 reason as there is way too much run out. Between the quill and the chuck you could have anywhere from .030" to over .100" runout between the two. Reason 2- then there is the issue of not being able to accurately tram in the head to the table. This can only be done on a verticle mill. If your working with a nominal shaft size of .275", and a I.D. on the bushing bore of .278", that's .003" , or .0015" per side. if you drill press has .040" runout, and the head of your equipment is trammed in to plus or minus .040", well you can fiqure out the rest. It is also absolutely correct about a 10% increase in shaft size negatively effects flow. On the race Harley-Davidson carb/carbs for example, it is common practice for some engine builders to mill the one side of the throttle shaft. Even machining tricks to the screws are performed. A blueprinted carb is no diffrent from a blueprinted engine, its all in the details, the more details, and the way you interpret the rules, generally has a profound effect as where you finish on race day.
Dan, What I do on the 94's (2100 is a replacment carb) is to sandblast the shaft holes in the base to "bring up" the metal. then I install either stock or .003" oversize shafts, to give .002 to .003 movement. The critical part is making sure the end carb throttle plates are completly closed.
I simply buy bronze sleeve bushings at the hardware store, drill out the base in a jig, then insert the bushing with red lock***e, then ream to size for original shaft that has been built back up. This is for 94s. As Bruce said for 97s, get a new Stromberg bushing (Uncle Max) and drive it home!
On the shafts...what "Traditions" is talking about useta was called slabbing. He has a mill, but tuners used to file away the thickness of the shaft parallel to the plate in the area of the bore only, leaving thicker steps to support the screws. The shaft can become dramatically thinner, but with what we are discussing the shafts must be very well fitted and the linkage smooth and slick before you proceed. The shafts obviously lose a lot of strength and can be twisted easily. I too believe there is no way in hell a drill of any sort can stay on axis running through a hole that is worn eccentric. I do not have a mill, so with 94's I am very, very picky at the fleamarket and buy only tight carbs. Strombergs don't matter now that bushings are readily available again.
I'm wondering how br*** can wear the steel bushing or the cast base..If you look at the throttle shaft you will see the wear and it is due to the cast iron of the base..Locate stock 97 shafts and replace..The bushings are, one for the choke lever and the other is for the manual throttle linkage.. Bruce is correct, larger shafts reduce the CFMs.. Duane..
Br*** does somehow wear the bushings...my flying guess is that when a gap starts to open, incoming crud embeds in the br***, turning it into an abrasive tool.
I saw a Holley 4 barrel carb using a vacuume line going to the shaft leak the guy says it worked good
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