Tackling a Weber rebuild

[Tony]

Looking closely at the carbs on my 1993 Supersprint, notice some seepage around many seams, rubber O rings crumbly and every spark plug reading different, think it may be time for a rebuild. With the carbs out I can access the distributor much more easily. Question is, how difficult is it to rebuild Weber DCOE 40's? Worth having it professionally done for lots of money? How thoroughly do you drill down? Just gaskets? Replacing needle valves & jets? I'd like to do the work myself to save the money, but I've heard they're complex and best left to the experts.

 

Anyone been through this? Practical advice, pitfalls to avoid, etc?

I've found several suppliers of rebuild kits, but do any offer the best/most complete kits?

 

Planning on starting this soon to allow plenty of time to work, but am a bit leery about jumping in with both feet before hearing other people's experiences. So far, answers to my other questions have been great; really a gold mine, very helpful and much appreciated!

 

Thanks,

Tony

[bball7754]

Tony - Rebuilt my Webers about 3 years ago, and it's really pretty straight forward.

 

I purchased a few Weber books, took notes and pictures. But, it's really just take it apart, replace the perishables, and put it back together. Nothing too tricky.

 

I borrowed an Ultra-sound cleaner for the parts, but it wasn't large enough for the carb body. Took them to a carb repair place that did Ultra sound cleaning.

 

Don't remember who I purchased the repair kit from. Pearce Manifold is good source, as is Dave Bean.

 

It's a good winter project.

 

Steve

[speedwagon]

Webers and dellortos are fairly straight forward. Get a book, (follow the directions),, and when done buy or borrow a wide band a/f meter and use it to determine what to or not to change. Modern wide bands make jetting much more of a science than reading plugs. They are costly but dam well worth it. Tip; float level and fuel pressure are the most critical items with either. Add fuel cleanliness to that list. good luck

[SCH]

There's a couple of really good YouTube videos on how to rebuild/reassemble Weber DCOE carbs. The two videos show a 45 DCOE, but the 40s are essentially the same.

 

45 DCOE 13 Weber Assembly Video Part 1:

 

45 DCOE 13 Weber Assembly Video Part 2:

[Tony]

Received the Haynes Weber Tech book which has very detailed instructions on rebuilding the 40 DCOE's requiring lots of special tools and a fair understanding of Webers. Not really interested in going that deeply into this rebuild though. Know it needs some gaskets and probably cleaning. So, how far do you need to go before putting the body into an ultrasonic cleaner? With less than 5K on the carbs (but 20 years of use), I don't think it will need a complete rebuild. Jets and passages could be cleaned with carb cleaner and air; not ready to pull out every part........

 

Thoughts?

 

Thanks!

[bball7754]

Tony - As I remember, the only thing I didn't take apart/remove were the butterflies and shafts. I didn't need any special tools.

 

I used the Pat Braden "Weber Carburetors" book, and the Des Hammill "How to Build and Powertune Weber and Dellorto Carbs". Think I also purchased the Haynes manual, but didn't really use it.

 

Steve

[ihckb2]

As long as the butterflies are free moving and the bearings are smooth running, don't touch the shaft and butterflies. Putting the bodies in a altrasonic cleaner may in fact cause migration of particles into the bearings, so be careful with doing this.

If your carbs have little mileage and have been sitting it is more likely just a thorough cleaning of the parts and cavities you can get at easily, new gaskets,O-rings, removal of the jets, etc.

Record settings prior to taking carb apart, i.e. needle seat turns etc. Do not over torque needle seats. Use these settings on assembly and fine tune from there when carbs are back on.