ok, my set of weber 40s... they are old(built in the early 80s by his estimation). my mechanic cannot replace the throttle bearings and thus, they do not idle right once the engine gets warm, it's like they are always slightly "cracked" open, when warm.
is there a place that can rebuild these and make them "new" again? or is it time to start carb shopping?
fron what I understand, the new carbs have a plate on the front, and one on the back that can be removed to replace the throttle shaft bearings, but this set only has 1 plate, so the bearings are not replaced(at least by normal means)
On my 44s, the bearing pops right out when you drive the shaft out...
You mean #21 on this diagram?
yea, that's different than mine
on this page, for example:
http://www.cbperformance.com/catalog.asp?ProductID=1254
you can see that the carb has a plate on the front AND back... one with a spring, one with just the throttle "ear"...
my old-ass carbs do not have the rear piece, or have the spring on the front. the back is just a plain piece, no movement or screws.
I'm really thinking this is going to end with a new set of carbs, but if these can be re-freshed for less than the $500 for a new set...
Wayne, I think I have the same carbs that you do, and have the same problem. The 44s are SUCH better carbs, it seems. But I am reluctant to pull the shaft, as I have heard horror stories about killing the shaft during removal of the roll pin.
Zach
............Wayne.... are you trying to say that your carburators...are so OLD...that one or both shaft bushings are/were installed from the INSIDE of the bore, and therefore the shaft ...(and of course the butterflys) must be removed to replace them????.......Murray
from my understanding, yes. I think... what I am really pointing out is how the new carbs have a way to remove the bushings on each end, as shown in the photo.
supposedly in the mid-80s weber design changed slightly...
using this picture as an example:
mine only has one side, the other side is flat.
Zach, I'm not sure I need 44s, but if I have to buy new carbs, it will definitely be a choice, since they are roughly the same $
So, is there anything preventing you from removing the butterflies and pulling the shaft out?
Maybe you don't have bearing...
..........Do you have a little mechanical aptitude, ?...can YOU get the carbs off?/and on...the solution is not cost effective If your mechanic does the work...(at EST 60.00 hr+)....
.........It is entirely possable that the "butterflys" are just bent a little....due to years of not only use but -backfiring thru the carbs....., and the IDLE air bypass screws (the tips) are bent/blunted ....and maybe the idle screws are too....Is it time to rebuild the carbs anyway?....are they grubby, dirty?......?....could YOU rebuild them?....(take them apart and reassemble after cleaning)...?.........
wayne, contact the folks at Air Cooled Enterprises (ACE) 801-943-1234 and see what they suggest. a set of carbs can be rebuilt (+jetted to spec with the info), setup and hot tested for far less than what a set of new carbs will run. i was very pleased with the reworking of my 44s.
k
found a pic of the carb, specifially the back that I'm talking about...
it's different than the others I've seen, but maybe ACE can fix them
on a side note... SirAndy, why can't we link photos from our own blog, without having to d/l and resize them again?
Um... have you taken off that nut and looked behind that round washer? You'll find the shaft bearing there.
.........YEP.........take off the nutand washer......and there she-be....AND It looks like you have an adjustable acc.pump .....the thing between both bores, has a rod with a spring behind it, attached to the cover in the middle of carb....this means ....YOU DO NOT HAVE the oldest design weber., and yours should be able to repaired easily.....I too understand ACE...does quality work, and has parts.
I will take it off one side when I get home, and report my findings... does it take a special shop/tool to replace these? I was told these were
pre-bearings... on the front there is not the springed piece as shown on the other carb... it's basically the same except it has a throttle stop, idle screw and throttle ear.
should these be repairable by moi? or just send them to Ace?
...........well , you were told wrong.....Now arn't you glad there is a 914 (world) site to go to for information......for you ,as they say, ACE is the place...........Murray
ok, well, here's the deal, ACE may not be cost effective in this scenario, but maybe I'll send them in for the final estimate, by the approximation given, it would be about $50-70 cheaper per carb than Empi HPMX carbs.. if that estimate is accurate, perhaps new carbs or good-used ones are in order... but that price was for EVERYTHING they do, they do NOT do bushings, bearings only.... I'll inspect the bearings and post pics. if it's the bushings, then new carbs are the only solution.
I recently changed my bearings... They were only about $5 each. I did, however, need to remove the butterflies and acc. pump pin so I could drive the shafts out (to push the bearings out of their bores).
If you work fast, like I do, you can rebuild them in about 8 minutes.
https://www.youtube.com/watch?v=MFywh5aC52A
cool, where did you get the bearings? also, can one get the shaft/ butterfly hard parts still or no?
right now my thought is "what do I have to lose? an afternoon?? " worst case scenario is it's not the bearings, it's the bushings in which case I'm right back to "gotta buy new carbs"
best case scenario is it might cost me $10-100 bucks in parts and kits to do these again...
I say: give it a try yourself!
I think you can get most of the parts here: http://www.redlineweber.com/
The hardest part is undoing the screws that hold on the butterfly disks. The are usually either loctited or physically deformed so they don't vibrate out. pushing hard with a screw driver on them can cause the shafts to bend. If they're the deformed style, you can trim off the deformed part with a dremel tool - then they're much easier to manipulate.
My bearings were pretty shot - they felt dry and a bit "gritty". Ball bearings don't perform that well in an "oscillating" environment... but we have to use what we can!
the bearings looked ok, so I called wes, he replaced them when he was rebuilding the carbs :| but the BUSHINGS are shit. he replaced the bearings eventhough they didn't look bad. but the slop was still there because the bushings are crap...
we put together a plan tho, to make due for a little bit we'll adjust the idle down some, making it a little harder start(it's very easy to start now) but will idle lower when warm. this will do until I get the cash for a good set of used dells or the empis(still not sure I want them based on some of the things I've read)
What number (in that diagram I posted earlier) are these bushings you're talking about. I have to confess, I don't know what you mean.
according to ACE, and Wes, they are somewhere in the body itself and require special tooling to remove
ACE said they can't replace the BUSHINGS on 40s, because they would have to change their "setup" and like I said there's probably not financially enough reason for them to do that, it's already close to the same price as replacement to do a FULL rebuild...
I've made bushings before on my mini lathe but it takes time to fit each bushing. I'd say I can do them, but cost plus shipping and it's again too much scratch.
Bieker can do throttle shaft bushings. I think he specialises in the Solexes the 356 guys use, but he's probably the go-to guy for this operation. He won't be cheap, but it will be right.
http://www.biekerengineering.com/
If the 40 IDFs are manufactured like the 44 IDFs (and I think they are), there are no bushings. There is just a long "bore" that the throttle shaft goes through, where it's supported on both ends by a sealed ball bearing.
This bore is a pretty close fit to the shaft, so it minimizes air leakage into the carb throats - but, if your throttle shafts are straight, there should be no wear in this bore. And, even if there is a little wear, that's what the air adjusters (#37) are for.
I believe you mentioned before that you have some kind of slop or play that's causing the butterflies to be "sucked closed" - that could only be caused by a loose throttle linkage, or by a loose actuator arm (#17).
It's also possible that the bores for the bearings (on either side of the carb housing) have worn a little bit. I saw that on one of my carbs - the bearing slid in and out with no friction. But there wasn't enough play to cause the butterflies to move on their own. That carb had a slightly bent shaft, and I think that was the root cause. Anyhow, I straightened the shaft and used a very thin piece of shim stock (0.001") to make the bearings snug in the housing - just snug enough so I had to tap them in with a hammer. This way, the outer race of the bearing is stationary with the carb housing, and the inner race will turn with the shaft - providing "ball bearing-ness".
I don't want to say anything bad about ACE, because I've never used them - but, after taking my carbs completely apart, inspecting them and learning how they work, I have no idea what "bushings" they're talking about.
I can see how other brands, which don't use ball bearings, use some bronze or bass bushings to support the throttle shaft - and to replace those, one has to first machine out the old ones and press in new ones (like valve guides in a head). But, my Weber 44 IDFs don't have anything like that.
since the car is dry-docked, maybe I'll try to pull the shafts and check and see if the bearings are fitting tight... are there any "watchout" things that might keep me from getting it back together correctly?
thanks for the info, I'll keep everyone posted, of course
ok, who said "linkage"?
because it was the linkage, kinda...
the springs were not strong enough to really snap it shut tight.. even though there was no gap against the idle screw, I lowered the idle, and changed the angle of the carb springs to compensate for the throttle shaft being worn and having very little tension in itself.
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