Idle Mixture Screw - Shape

[csd1982]

Im working to tune my carb again. I'm a bit confused. First I have read the FAQ and other posts on this. I have good vacuum and don't think I have a vacuum leak. However when I tighten down the idle mixture screw the engine does not die. Furthermore when I take the screw out it seems to have a slight bend in it towards the bottom. Is this right or should it be very straight? Did I bend it by tightening it down too much? Is that possible? The idle mixture screw seems to do nothing really at this point.

I have a 1975 2F.

Also I have to keep the idle RPM's closer to 800 else it will die (timing light).

Furthermore my Fj40 will sometimes die if I'm in neutral unless I keep the choke partically closed.

 

[RobNasty]

Idle

 

[csd1982]

Idle

Yes I know..

I cannot edit the title now.

I was just looking on how to edit that but cannot find it.

 

[65swb45]

Please post links to the threads you already searched on this heavily-covered topic.

 

[luvdamud]

Here's an example of what Mark suggests. I did a simple search her for "1975 idle mixture" and this is a thread that looks promising.

Carb tuning and engine timing issues

 

[csd1982]

Please post links to the threads you already searched on this heavily-covered topic.

adjusting or tuning my 77 fj40 carburetor

Carb Works Great!

And some posts by pinhead

I did not see anything about the shape of the idle speed screw. if there is a slight bend in it towards the bottom or not. If that is answered somewhere paste the link

 

[csd1982]

Here's an example of what Mark suggests. I did a simple search her for "1975 idle mixture" and this is a thread that looks promising.

Carb tuning and engine timing issues

Yea I know that was a old post of mine....

Im asking about the shape of the idle speed screw not how to adjust the carb. I know there are posts about this as I have started a few of them but I just noticed the screw is bent a bit on mine.

 

[luvdamud]

Can you post a pic of your idle speed screw, so the group sees what you see?

This is a very visual community that likes pictures (pictures, water colors, finger paints are all ok).

 

[csd1982]

Can you post a pic of your idle speed screw, so the group sees what you see?

This is a very visual community that likes pictures (pictures, water colors, finger paints are all ok).

Yea when Im back home next week.

 

[luvdamud]

Yea I know that was a old post of mine....

Im asking about the shape of the idle speed screw not how to adjust the carb. I know there are posts about this as I have started a few of them but I just noticed the screw is bent a bit on mine.

Sorry

 

[csd1982]

Made the title more specific so people don't get their panties in a bunch about topics being covered already.

 

[micruz60]

I do not believe it should have a bend in it, a smooth taper to a point.

 

[Splangy]

You're never going to be able to adjust your idle mixture if you're not idling.

TONS of threads on this subject.

 

[csd1982]

I got around to getting the screw out.

I assume this is jacked up...

Could I have done this by over tightening it down to start the adjustment process?

 

[thebigredrocker]

Here's 4 of mine. Yours definately looks altered.

 

[csd1982]

I think maybe my carb base is messed up...

Could the shape of the hole be messed up and reshaping the screw when I tighten it?

 

[thebigredrocker]

Someone with extraordinary hand strength over tightened that. I would guess your cast iron base is fine. You could straighten it out and see how it performs or Cruiser Outfitters sells a carb kit that includes a brand new mix screw.

 

[csd1982]

Someone with extraordinary hand strength over tightened that. I would guess your cast iron base is fine. You could straighten it out and see how it performs or Cruiser Outfitters sells a carb kit that includes a brand new mix screw.

Thanks, I was wondering if Cruiser Outfitters kit had the idle screw.

I know keyster kits do from https://www.siriusconinc.com/mobile/ but the distribute is out of stock.

Still strange right?

I assume since it's in that shape it will not seat right so I can not get the idle mixtures set right....

 

[bobm]

Don't take much to bend them. 1/8th to 1/4 will do it. Seen it b4

 

[65swb45]

Im working to tune my carb again. I'm a bit confused. First I have read the FAQ and other posts on this. I have good vacuum and don't think I have a vacuum leak. However when I tighten down the idle mixture screw the engine does not die. Furthermore when I take the screw out it seems to have a slight bend in it towards the bottom. Is this right or should it be very straight? Did I bend it by tightening it down too much? Is that possible? The idle mixture screw seems to do nothing really at this point.

I have a 1975 2F.

Also I have to keep the idle RPM's closer to 800 else it will die (timing light).

Furthermore my Fj40 will sometimes die if I'm in neutral unless I keep the choke partically closed.

What constitutes "good vacuum "?

Yeah, the screw is bent. But I think it's the victim, not the culprit. I'll give you one no charge with a qualifying order.

Best

Mark

www.marksoffroad.net