Dellorto Pump jets, where is the hole suposed to be?

[tdafforn]

HI Guys,
have been having trouble with my +2 bogging on sudden acceleration...
Seemed like it was something to do with the pump system on the DHLA's I have fitted..
The carbs have been rebuilt, seem pretty good.
Anyhow the suggest (partly from the list) was that the pump jets maybe too rich (they're 45s)...
Anyhow I have bought some 40s and while installing them I noticed that the jets I removed seem to have holes in the bottom pointing down, whereas the new ones have the hole on the side (where i would have expected them if they were supposed to be shooting the fuel into the inlet tract).
I also notice that the new ones would have had holes in the bottom (perhaps a by product of their production), but they had been closed off..
Anyone have any ideas which is correct?
Cheers
tim

[rgh0]

Tim

Both Weber and Delorto jets should have holes in the sides to spray down the carb towards the engine. The jets have a flat in the locating seat to orient them the right way. Sounds like your old jets where "modified" by some DPO.

Rohan

[tdafforn]

Thansks for the conformation, I thought they would be the same idea as for the weber jets...
Looks to me as though the DPO drilled out the bottom of the jet...
Trouble is, I don't think the jets had side holes...
I wonder where he go them from!
Cheers
Tim

[cliveyboy]

All my jets on the Dellortos have holes in the end but when I bought some more they had holes on the side.
Clive

[tdafforn]

Very odd...
It makes complete sense to have them on the side, but no sense to have them on the end!
I'll let you know how I get on with the new ones on the +2
Cheers
Tim

[mark030358]

Hi there,
two types made. early type point down, while later ones point in direction of airflow (ie into cylinder)
cheers
Mark

[tdafforn]

Brilliant, thanks for the info mark
Cheers
Tim