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Sat Mar 06, 2004 11:13 am

Here's the problem:

My timing is set to 30 degrees btdc witha bosch009. 1776 pancake engine for type 3.

Idle is running high (i think) at about 1100-1200 rpm. The idle adjust screws are all the way unscrewed so as not to touch the throttle levers. It is still idling this fast.

The problem is, the throttle lever won't rest against the idle screw housing. It is stuck about 1/4 inch away from the housing and I can't get it to get any closer to the housing. So I was thinking this is why it is running so high. Both carbs are like this, but one more so than the other. Is it okay to keep them stuck like that? Is it normal? I have taken off the linkages and tried to figure out why they are stuck and not up against the housing, but I am totally clueless. Please help me with any suggestions to try.

I am using dual weber 40s.

Thank you,

shaymus

Sat Mar 06, 2004 11:53 am

shayme wrote: Here's the problem:
My timing is set to 30 degrees btdc witha bosch009.
shaymus

That is a problem, unless you set it at 3,000 rpm or so.
At idle, you should be around 7-9*BTDC.
Colin

Sat Mar 06, 2004 2:32 pm

Sorry about not being clear. I set it at 30 degrees at between 3000-3500 rpm.

Sat Mar 06, 2004 2:35 pm

That's right!! 7-8 degree's and idle. 30 degrees max advance @ 3-4000rpm

Sat Mar 06, 2004 2:43 pm

what carbs and linkage are you using?

Sat Mar 06, 2004 2:54 pm

They are dual 40 webers. i don't know what kind of linkage. This long hexagonal rod connecting the two with an arm on each side going down to the idle speed screw and throttle lever. The throttle lever will not sink back up against the screw housing when I unscrew it all the way, so I'm wondering how to unstick it, or if it is normal to have rpms at idle around 1200 at the lowest that I can adjust it with the idle screw.

Sat Mar 06, 2004 3:22 pm

check dwell 1st. then timing, then carbs. r ur carbs used? check 2 c if the throttle shaft r closing all the way. if not u will never get idle down. after that disconnect linkage from carbs. u'll adjust linkage to carbs not other way around. what r u using to sink the carbs? :shock:

Sat Mar 06, 2004 3:30 pm

The carbs are used, they are about 4 years old. I don't have anything to sink the carbs, I'm just trying to do what I can and get the idle down and sink them later on (I dont drive it every day). I don't think the throttle is closing all the way. Is there any way to fix that?

Sat Mar 06, 2004 3:41 pm

You need to check with the carb off the manifold to c if butterfly closes all the way. and you need a sink tool. if the butterfly doesnt close off all the way those carbs have a problem bro... :x

Sun Mar 07, 2004 7:35 am

Before you even THINK about driving around with these carbs - you need to synchronize them - one to another. You can easily obtain /buy / borrow a synchrometer / vacuum gauge, or (if all else fails) I've used a length of fuel line in the barrels (one at a time) and held the other end to my ear - listening for variations from barrel to barrel. This approach is "iffy" at best - but better than nothing.

Next thing you should do - is get Pat Braden's book "How to install and tune Weber carbs"...improperly set up carbs (especially big 'uns) can destroy your motor if not set up properly, by allowing too much fuel in - rinsing the oil from your cylinder walls, and causing cylinder wall damage!!!! (or mthey could be too lean - and cause your pistons ta' melty melty.

As someone else stated - set the linkage up relative to the carbs - not the carbs to the linkage! check to see if the levers rest on the idle screw BEFORE you attach any linkage. This can easily be done before installing themon the engine.

Webers are easy and fun, but must be approached with systematic patience. You probably have one carb that's far ahead of the other - so that the opposite carb can't rest on it's idle screw.

HTH!

Zwrench

Sun Mar 07, 2004 7:50 am

there is too much to tell over an e-mail...like first of all... is the carb jetted to your engine?? send me an e-mail and I'll give you my phone # I live in the san diego area and work for Bernie Bergmann. (his engine builder) if your still having problems. cajalco@san.rr.com

Sun Mar 07, 2004 11:10 am

Thanks for the help. I have never tried to adjust carbs before so that is why I'm so clueless. Will a uni-synch tool such as this http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=46097&item=2465184666 work for the webers? I noticed it was a lot cheaper than a synchrometer, but I'm not sure if it will very accurate.

Shaymus