lack of power

[daz4ria]

hi all , my 1.9 watercooled engine , as a problem can you help
starts first time , ideals no probs not missing but as soon as i go to drive off there is no power and struggles to get above 20 miles mph then all of a sudden i get a burst of speed and then a few secs later struggles agian as if im driving with hand brake on ( which im not by the way ) just put a new fuel pump on from just kampers so should not be that .the van is used daily and as not been standing for a while has any one got any ideas what it might be . it has just started to do this today, no probs before
thankds for looking and for any feed back
taz

[kevtherev]

there are two possible causes in my opinion
1. you have an induction air leak
2. your transfer jet is either blocked or the diaphragm in the accelerator pump has failed.

try this test for the transfer jet..
Take off the pancake duct from the top of the carb, hold open the choke flap, get someone to press the accelerator, you should see a good squirt of fuel spray down the throat.
you can see the accelerator pump here, the diaphragm is no. 11.



this is still available should it be faulty.

An air leak will be noticable by a backfire or "popping" on the overun