WH20 Multiball problems

[Agentbarry]

Hi all,
Lately my WH20 has been developing a strange fault involving the ball popper that transfers the balls from the lower playfield to the upper playfield, it seems to happen the most once you have all 3 balls locked and activate multiball.
When it tryes to pop up the first ball it seems a bit weak and more often then not the ball wont make it all the way up, by that time another ball is already trying to be popped up and then you end up with the balls all stuck in the wireform trying to be popped up, the game then does a ball search but will never be able to push all the balls up.

I have replaced the solenoid thinking maybe it was getting weak, and have taken out the whole mechanism looking for some signs of wear and tear but cannot for the life of me find anything that fixes the problem.

Further more it will usually play a couple of games with no problems, but after 10-20 mins it will start doing it again

Any help is appreciated :)

Cheers
Allan

[robm]

Check the popper is screwed tightly to the underside of the playfield, slop here will make it weaker.  I also had a similar problem and i moved the wireform slightly, or tightened it and it fixed the issue.

[pinnies4me]

The rubber grommet at the base often turns sticky with age and reduces the power.

[Agentbarry]

cheers for the suggestions, will try them out today and hopefully get it working again