New fuel pump and now it won't idle.

[yetihair]

Well as the title says I had to replace the fuel pump but now it won't idle.
I can get it to start and it will rev and I can hold the revs so I don't think the new pump is to blame

Does anyone have any ideas? Any help on what I might have moved, disconnected or damaged is appreciated.
1.9 DG pier burg carb

[itchyfeet]

Why did you need to replace the pump?
Could you have disturbed the electrical connection to the bypass air cutoff valve?, check its got 12v and clicks when you conect it
have you held the throttle open until hot, if no do that and see if it idles hot

[CovKid]

Beat me to it so had to E D I T Itchyfeet. Possibly you may have disturbed some much in the line which is now blocking the idle jet or tubes within the carb? Thats the other possibility.

[yetihair]

Cheers guys,
I had to replace the fuel pump as it had worn out and wasn't pimping. The pivot on the pump arm had worn loose so wasn't getting the full throw.
The bypass air cut off valve clicks fine.
I haven't revved it till it's hot as I'm also I'm the middle of changing the temp gauge sensor (proving to be a pita as it fell apart with half of it stuck in) and I have a hose to change too.
Is it an easy task to check the idle jet?

[itchyfeet]

Get it hot first, it could be a choke issue

could be dirt in the carb but there is a cone filter in the inlet pipe so no reason why it should get through that unless its missing or holed, worth checking it though, need a blunt end screw to pull it out

[kevtherev]

yes clogged idle jet

[yetihair]

There was something blocking the idle jet.
Its all reassembled but since I have it drained of coolant at the moment for some hose changes and temp guage sender change I cant start it up to see.
I'll be filling it up and bleeding it as per Simon's method this evening so i'll know then if its solved the problem.
Cheers for the advice I'll update later.

[yetihair]

Hmmm, so I've bled the coolant which was a bit of a faf since it still won't idle.
It's been fully warmed up (to the point where the rad fan kicks in) but take foot or brick off accelerator pedal and the revs drop till it stalls. I'm thinking the idle adjustment screw needs a turn??
I checked the idle jet again and it's still clear.

[kevtherev]

OK
I am going to presume you have checked the idle speed cut off solenoid, and that it clicks when the ignition is turned on.?

[yetihair]

Sure did, one of the first things I checked as I thought it might have been knocked when changing the fuel pump.

[kevtherev]

Does it idle when the engine is cold after setting the idle speed with the accelerator?

[yetihair]

Cheers for the help kev.
I upped the idle screw a little and it is idling from cold but the revs are all over the place and too high 1100rpm. If I adjust it back down towards 800 rpm it will stall.

[kevtherev]

950 is the idle speed.
What do you mean by all over the place?
is it idling erratically?

when cold, the idle speed stepped cam operates the butterfly and cracks it open.
It should idle high when cold (2000 rpm, then 1500, then 1250,)
then after 5 mins it should be at 950

[yetihair]

Sorry I thought 800 was the idle speed.
I'll have to check it when it's properly cold and the choke is closed to see what the revs are like.
I guess it is sitting about 950 but it is quite erratic.
http://youtu.be/NeU5zB24qYM" onclick="window.open(this.href);return false;
Video of it idling after turn the idle screw up.
Cheers

[yetihair]

So it was idling as per the video and I thought it might be okay to take it out for a run back home from work where I work on it.
I got about 1/2 mile down the road and it lost power, just seemed to be starved of fuel. Managed to get it back to the office and it started idling at 2000 rpm (probably due to my turning up of the idle screw)
I think the carb must be full of crap and in need of a good service and clean out and set up.
I've run out of time to get that done before taking it to holyhead for a ferry back to ireland on sunday. Game over for now.
I'll get it booked in for some professional attention after easter.