Dellorto DHLA 45s leaking both pump jets on front carb - SOLVED MOSTLY, maybe now

[anthonym]

Dellorto DHLA 45s leaking both pump jets on front carb of twin carbs.

After much searching I am exploring the float height being too high at 11mm instead of 15mm. I will be checking this again tomorrow.

However I am guessing really. 

Anyone been down this path?

Video of the problem, shows all 4 barrels, it is the 3rd and 4th in the video with the dribble (in fact cyls no 1 & 2)

https://www.dropbox.com/scl/fi/j3udx9y75x3a30hh1mvbh/IMG_7969.mov?rlkey=brscmfg6nzjdvwugqobtxkcyj&dl=0

I am also wondering if the dribbling fuel is not coming down through the jets but simply leaking from the float chamber and the jets are the natural path for the dribble.

This issue explains why the Carbtune Pro https://www.carbtune.com is giving odd results.

Anthony

Solution: reset the floats, but better, see next post

 

[anthonym]

 Dribble reason

 

[SM25T]

Drib Bling !

[richardm57]

Hi all, My 7 was supplied as kit late 1987,

I wanted webbers but was told not available as all webber production was reverted to supplying replacements for all Fiesta BB carbs which were crap.

This was early 1988 so may have been 1987 also, so bought Dellorto"s.👈

At about 45,000 miles carbs started to leak onto battery🙈  It was the all metal needle valves leaking and overfilling float chambers.

For needle valves use the Viton seal type.

I would have though 45 perfect for 1700 bdr, i use 48s on 2ltr bdg.

Think i loose a bit of top end over webbers but smoother drive low end.

 

Edited October 18, 2023 by richardm57

[Gridgway]

2 hours ago, richardm57 said:

Think i loose a bit of top end over webbers but smoother drive low end.

 

Is there such a thing as low end drive on a BDG?  Let alone smoother!

[anthonym]

Interesting Richard m57 - Maybe that's why mine has them too. Mine were refurbished some years ago and only brought in to use last year so sounds like I dodged a bullet. 

I'll keep an eye on my float levels.

My accelerator pumps now work and have changed the car completely. One diaphragm is missing its spring so monitoring that too.

Edit: here's how I fixed it: https://www.supersevenheaven.com/BDR-Dellorto-adventure/

- Anthony

Edited October 26, 2023 by anthonym