HIF 44 idle problems

[RussLCV]

I have a rebuilt HIF 44 (well 2 actually) powered by a Webcom WP502 pump all is working well and fuel is getting to the carb. The engine is a midge 1275 with metro head and has been started a number of times.

The engine runs well when started with full choke and then half choke and lots of power on the throttle pedal, but once choke is returned she will not idle and one has trouble keeping engine running on throttle?

Both carbs have been fitted and run the same so this must be me and the adjusting

Any ideas please

[bmcecosse]

Sounds like air getting in somewhere! Swamped by the 'choke' (mixture enrichment really) - but when that is cancelled - the air leak makes the mixture too weak.

[RussLCV]

Thanks bmcecosse, but not sure what you mean. Can you point to where or what I need to do or look for?

[MarkyB]

Someone else had the same problem recently, I think something on the bottom of the carb or the heat shield was touching and stopping the carb lining up properly.
I think it was the heat shield and it just needed bending a tad.

[RussLCV]

A couple of pics and questions I hope that can be answered

see image below which shows carb set up and the plate is not fouling anything.[frame][/frame]

Next 2 images show breather pipes & fuel inlet which is the bottom, what attaches to the stub end shown and the other I have connected to the front engine breather (1275 Midget) is this correct? or should it go to the carb air filter, I intend using a Mini one[frame][/frame]



lastly what attaches to this on the air filter housing and where does in go on the carb. I have read Mini/Metro/Ital & Marina manuals but can find now. I suspect this is causing my idle and adjustment issues?



Can anyone help or advise please[frame][/frame][frame][/frame]

[MarkyB]

I think there is only one breather pipe, the other pipe was for a mid range weakening device and should be blocked off.

[RussLCV]

which one is which? Any idea? Also will this effect by idle issue?

[JOWETTJAVELIN]

on my 1275 with same air filter these pipes aren't connected to anything either, and every one I've had was like this, so I wouldn't worry if I were you.

[MarkyB]

I think it's the angled one.
You could always block it with your finger and see how the tick over is affected.

[bmcecosse]

I think that brass pipe is just the overflow - but no harm trying it blocked off. The spigot on the air filter is for a breather pipe from the crankcase - which you have already connected directly to the carb.

[Roni]

Where is the pipe on the inlet manifold going to? The photo doesn't quite show it.

[RussLCV]

I think that brass pipe is just the overflow - but no harm trying it blocked off. The spigot on the air filter is for a breather pipe from the crankcase - which you have already connected directly to the carb.

Is that Ok BMCecosse or should I remove................and what connects to the breather in its place

[RussLCV]

Where is the pipe on the inlet manifold going to? The photo doesn't quite show it.

Brake servo

[bmcecosse]

The breather is best connected directly to the carb - as you have done.

[chickenjohn]

I have a rebuilt HIF 44 (well 2 actually) powered by a Webcom WP502 pump all is working well and fuel is getting to the carb. The engine is a midge 1275 with metro head and has been started a number of times.

The engine runs well when started with full choke and then half choke and lots of power on the throttle pedal, but once choke is returned she will not idle and one has trouble keeping engine running on throttle?

Both carbs have been fitted and run the same so this must be me and the adjusting

Any ideas please

Check for play in the throttle butterfly spindle, was this replaced?? This can make a big difference to idling problems.