YASP - Series 90 failing to start

[gaffers]

Having recently acquired a series 90 at a decent price I was assured it was working. Alas, I cannot get the bugger to go.

Originally I thought there was a fuel delivery problem due to rusting tank and blocked filter. I changed the filter, flushed the tank and now when priming I get the wet finger (ooo-er)

I took the plug out and confirmed a healthy spark.

Edit: it's a series 90 EFNR and yes it was in neutral

Help, please......

Matt

[charlesp]

I too have an EFNR, and had problems with rust and the like in the fuel. I cleaned the filter, changed to a plastic tank and sure enough she wouldn't go. Same as you there was a spark.

She runs now, reliably, after a very thorough blasting of the internal bits of the carburettor with Wynn's injector and carburettor cleaner.

[gaffers]

Good idea, I'll try that

[Horsley-Anarak]

Amal 400 series, main jet might be blocked.

Unscrew the black plactic fuel bowl, the threaded bit that the fuel bowl screws onto is the main jet.

Remove the main jet look through it, I have found that more often than not they are blocked if the engine won't start.

If it is blocked then you need to take care that you don't damage the jet unblocking it.

I have found that a bamboo skewer works well.

Good luck

H-A

[gaffers]

Ok the carb was pretty clean so took off the fuel line and the plastic cap was full of crud. That could have been part of the fuel starvation problem. Put it all back together and the plastic cap cracked confirmed when I opened the fuel tap again, fuel was seeping out. There is prob not enough pressure to feed the carb properly now, it took 10-15 pumps to prime the carb before the bowl was full and the inside of the carb is very very dry. Still no start. So I need to replace the plastic cap before I can go any further.............



......oh, John!

[Horsley-Anarak]

it took 10-15 pumps to prime the carb before the bowl was full :

There is no pump, you can hold down the float to over fill the carb for starting.

Is the main jet clean?

H-A

[gaffers]

Yes main jet is clean. Holding down didnt fill the bowl, only repeatedly pressing the primer worked but still not enough pressure I reckon

[Horsley-Anarak]

Young Adult Advice & Support Project (YASP for short)?

Open the throttle wide, squirt some petrol oil mix through the carb pull it over and it should fire.

It will let you know if there is life.

H-A

[gaffers]

Yet Another Seagull Problem

I'll give that a go tomorrow

[gaffers]

OK, squirting fuel into the carb she roared into life after which came the inevitable slow-down to stall during which another squirt brough her back up.

Excellent!

So once I get the parts from John I should hopefully get somewhere

[gaffers]

Ok, parts arrived today - that's a very fast delivery from John, again!

During lunch break I slapped them on and no joy. Having looked at the needle previously I noticed that there are 3 notches which the clip can fit into. The clip on mine was on the highest one (ie furthest away from the pointy end) I moved it down to the middle notch and after a bit of work she fired up, yet she dies on idle. I ran out of time so I reckon if I move it to the lowest tonight I should be able to get a stable idle.

Any feedback on which notch I should be using?

[gaffers]

Ok I'm not sure which of the notches are best but it's definately not the top one, I tried the lowest but I think that was too rich. I still have a fuel starvation problem, when warm the engine wont rev above idle and stalls once you open up the cab. If I keep my finger on the primer and open it up it works perfectly. As the fuel comes ok if I hold the primer I am thinking toward a float/bowl issue. Maybe I didn't use enough carb cleaner........

[Horsley-Anarak]

If you unscrew the float bowl, then turn on the fuel tap you should get a good trickle of fuel.

Then if you lift the float the flow should stop. This will tell you that the fuel system is good as far as the bowl.

I have not found that the needle notch position makes much difference; I keep it in the middle one.

have you cleaned the filter behind the banjo?

H-A

[gaffers]

Ok took off the carb again and gave it a real good clean with a new can of carb cleaner. Cleaned the filter checked the float, all ok.

Choke on, she starts ok, revs ok, idles ok.

Once warm, choke off, idles rough, revs kills the motor. If I hold the primer down and rev it works good.

I think although the fuel delivery is ok it is still not good enough. Time to take the tank off, treat it for rust and get new fuel line I think.

Oh, and it's not pumping enough water either, another job

[Horsley-Anarak]

The fuel line can get blocked with fine rusty sludge, blow through it to see if it is clear.

H-A