[stockman]

Could some one in the know explain what this is called and what it does.
It's on the RH side of the carby.

[JrZook]

That looks like a cold idle compensator. Uses a bi-metallic strip to open a passage that goes around the butterfly to increase idle speed when shes cold.

Dan

[stockman]

Ok. Makes sense. It has a vacuum line from above the butterfly and one below.

Not what I was hoping it was.

[royce]

no!

its for hot weather, opens to allow air in so as not to have a rich mixture and too high exhaust emissions, does up the idle at the same time

[JrZook]

stockman wrote:

Ok. Makes sense. It has a vacuum line from above the butterfly and one below.

Not what I was hoping it was.

What are you looking for?

[stockman]

JrZook wrote:

stockman wrote:

Ok. Makes sense. It has a vacuum line from above the butterfly and one below.

Not what I was hoping it was.

What are you looking for?

Not 100% sure.

Something that would cause the idle to run rough. Every now and then it will idle rough and stall. Went for about 3 weeks and didn't skip a beat. Then a week where say 1 in 10 it would do it.
It only effects the idle. Car still runs smooth, had power, and doesn't miss.

[mr_ron]

have you checked your fuel lines and filter? not a case of bad fuel is it?

[stockman]

Yep. Basically I have done everything apart from fuel pump. Done all the electrical stuff too. Tried different brands of fuel in both unleaded and premium.
Hasn't got any worse. Just every now and then it will idle funny and stall.

[FullyZooked]

stockman wrote:

JrZook wrote:

stockman wrote:

Ok. Makes sense. It has a vacuum line from above the butterfly and one below.

Not what I was hoping it was.

What are you looking for?

Not 100% sure.

Something that would cause the idle to run rough. Every now and then it will idle rough and stall. Went for about 3 weeks and didn't skip a beat. Then a week where say 1 in 10 it would do it.
It only effects the idle. Car still runs smooth, had power, and doesn't miss.

Sounds like a partially blocked pilot jet. Always good to have a fuel filter between fuel pump and carb to stop bits from the rubber diaphragm clogging shit up.

Either take the carb apart and clean it up or..... rev the car up and smother the intake with a rag while holding high throttle. Theres lots of dodgy ways to clear the jet, another being swapping ignition leads

[stockman]

Tried both the rag trick and swapping the leads.
It's possible to remove the jet without stripping the carb?

[SSSIERA]

nope

[FullyZooked]

No. The jet is in the base plate of the carb. I have recently found that car carbs are just as easy as any. Just don't loose the bits.

Give the whole thing a clean out while your there. I bet you'll find some nasty stuff in the float bowl

[stockman]

Ok. I might pull it down if it starts to annoy me too much.
What soft of filter are you running between the pump and the carby?

[royce]

Sierra carbys have a removable idle jet

I would think your problems might be a mixture issue but a clean carb is always a good place to start, rip the idle solenoid out and give it a squirt with some craby clean, then squirt some carby clean down the hole and let it sit for a bit, then jam some compressed air in the hole, wear goggles and keep clear cause fuel will go everywhere.

stick it all back together and see how it goes, maybe give your idle mix a bit of a richen out

[stockman]

Where abouts is the idle solenoid? LHS of carby, with single wire going to it?

[skyman]

stockman wrote:

Where abouts is the idle solenoid?

x2 I want to give this a shot on my boys carb.

[stockman]

Worked it out. It is the one on the lhs of the carby with either one or two wires running to it. Although I think the carbs used over there were different. I will take some photos later.

[stockman]

Bumping this back up.

Same issue again.
Idles real low and stalls.

Car has ran great and has not beem an issue for winter, but now it's warming up it's starting to do it again.

What could cause the issue, and is the warm weather a factor or just a coincidence?

[stockman]

I wonder if the fuel is vapourising?

[Drova]

With mine I found that the secondary
Butterfly wasn't returning to 100% closed
From high revs, it was ether sticky, jaming against
In the linkage, bad spring can't remember.
( all of the above) So at idle the secondary
was about 90% closed, and was letting in little
extra fuel/air Which it should only do in rapid
acceleration But that was the problem that was
Full overhaul, new idile solenoid lol

[stockman]

I will check this again tonight. Thanks.

[stockman]

Finally fixed it.
I know know the in's and out's of the Sierra carby like the back of my hand, except for one bit.

[stockman]

FFS.
The gremlin is back, after two days of running great.

The last thing I did was pull the idle solenoid off again and cleaned it out with a big compressor. Works a treat.

So I think there is something floating around in there.


Last night whilst fiddling I had the carby hat off. I cupped my hands over the top of the carby and almost sufficated it. When it almost stalled I allowed a little air through and held that position and it idled perfectly.
So does this mean it's getting too much air in.
I checked the seal and it was a little stretched, so fixed it but no different.

Any help would be great.

[BlueSuzy]

Wish i could help,

Its the one of 2 main reasons i went efi.

When was the fuel filter done?

When you get here, I have a box of carbs/bits if you want to play.
The last carb that i ran on mine made it go harder, but used more fuel as we put bigger jets in.

[stockman]

Fuel fitler and air filter were done not that long ago.

I have another complete carby and a box full of parts, but just want to avoid pulling down the carby thats in it.

The carby runs great and getts me 400k's a tank on standard tyres, it just idles badly.

ps turn your phone on

[BlueSuzy]

It is on. My reception comes from 50kms away..Yet there is a tower 2kms away..vodafail.