Dellorto DRLA 40 B. What jetting for a 2110cc Type 1 engine?

Attempted to remove my idle jets today as my long idle jet holders & O rings finally turned up.
@Dicky gave me some good advice before I started.
It was eventful!

This happened when I attempted to remove the velocity stacks, but I battled on!



Took me ages to get my first idle jet undone (Cylinder 4).
Finally got it loose but couldn't get it out, as I couldn't get my fingers round it.
Used some bluetac on top of the 'screw' to remove it.
Felt quite pleased with myself for about 1 second. The idle jet holder came out, but the jet remained in the carb!

Can you see the cheeky little git down its hole, laughing at me?




I consulted the dellorto guru @zedders, who was very supportive but had never seen this before.
The rolling Rd people had seen it before and told me to go an buy a 'brass magnet'.

A quick trip to Poundland & Iceland to purchase the new tool and bingo I got the little beggar out!





This is exactly why I think some people (me) are better off leaving things to the experts.
Idle jet on number 3 went much more smoothly. This jet was firmly in it's holder.

 

I got the long idle jet holders from Volksbolts https://www.ebay.co.uk/itm/381099828251?hash=item58bb51e41b:g:2iAAAOSwg3FUmbg3
as Eurocarb only sell them as part of a massive & expensive CB performance kit.

I also got new idle jet 0 rings from volksbolts: https://www.ebay.co.uk/itm/252781672995?hash=item3adaf63a23:g:LmYAAOSwax5YrNU8

they describe them as ethanol resistant, but they are no where near thick enough (see photos a few posts below).

Edit they are 1.1mm thick. The ones i removed are 1.5mm thick.


The ones eurocarb sell: https://www.dellorto.co.uk/shop/del...rburettor-parts/vhb-vhbz-vhbt-parts/o-ring-8/

are 1.5mm thick, but don't mention ethanol resistance.
Please note my measurements taken on crappy digital calipers so are only useful for comparison.

Eurocarb idle jet O ring dimensions are on their website.

So i can't complete the job quite yet!

 

Ha! Never thought of that.

 

Excellent idea on the sticks

Buy a 'brass magnet', that made me chuckle

 

Have you worked out why the jet got left behind?

 

yes when i got it out i tried it on the original idle jet holder and it just slid off/on, so it wasn't tight enough.
It feels tighter on the new tall idle jet holder.

The other one (number 3) was on much tighter and took some effort to remove

 

That is what the rolling road man said to me and his stick idea.

I have a pack of 100 bamboo skewers, i shall issue them to all dellorto owners for their specialist tool kit!

 

I’d suggest it got stuck because the carbs are full of sticky muck. Give them a good scrubbing !

 

Are you good scrubber, Paul?

 

Very generous

 

id cleaned them with carb cleaner prior to attempting removal of the idle jet.
The idle jet holder that came out looked pretty clean to me (although i've never seen other peoples)

See Photo below and tell me if it looks mucky?

I'm pretty sure it was just too loose.
Idle jet and old holder currently soaking in carb cleaner (o rings removed)
Long idle jet holders & main jet stack are in the carb, trying to prevent any dirt getting down the holes.

Can i spray carb cleaner down the idle jet holder hole and the main jet stack hole or is that a bad idea?

 

Yes you can, the only thing not to do is blow through them with a compressor as you risk blowing out this lead plug.

 

Thanks very much.

Can i also do the following without harming anything:
spray some carb cleaner down the little air holes (next to the main jet stack and idle jet holder)?
& or a thin pipe cleaner down the little air hole (or is that a bad idea as it may leave 'fluff/fibres')?
Pipe cleaner down main jet stack hole and idle jet stack hole?
Finish off with more carb cleaner to wash away any fluff/fibres?

 

I wouldn't use pipe cleaners at all personally but yes to carb cleaner anywhere you fancy just don't end up washing crap from the surface INTO the carb and making a blockage of your own creation!

 

Thanks, great advice.

Ok i wont use any pipe cleaners.

I've been cleaning 'up top' with the jet stacks still in.

I'll do loads more of this, before removing jets and squirting cleaner down the holes

 

I would because the jet holes are down in a low area created by the carb top and from your photos you have some gumph there ready to wash down into the holes.
Hate to say it but I'd personally either take the tops right off and clean the top of the bottom half or if I knew I was trying to wash out the holes the jets screw into I'd use the straw and try to blow the crud back out the top with a good squirt. It takes quite large (in the scheme of things) detritus to actually block the jets and it can't really get there other than falling down the holes when the jets are out or making it's way from the fuel reservoir where there shouldn't be any due to each carb having a filter screen built into the supply inlet.

 

I've only ever had one blocked idle jet shortly after fitting them so I know it was my own fault. Since then no problems for 6 years. A blocked idle is obvious because it runs lumpy!

 

Changed idle jet holders to long ones in 1&2 today, it was much easier as i used a wing mirror to help me see exactly where the screws were.

I did more cleaning before hand, but they weren't actually anywhere near as dirty as things look in the other photo(s) i posted.

I think a camera flash and freshly sprayed carb cleaner made them look filthy, but they weren't and are even cleaner now (especially the low area with the air holes).

Ill try and add an non flash pre clean photo