Confirm that this is normal for a FJ carb (1 Viewer)

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Just two questions about my FJ40 carb.

Was newly rebuilt 600 miles ago but now has stains on the lower shafts as seen in picture and around horn under cleaner neck.
I presume this is a norm as the shaft's have no seals?

The site bowl line A is the level when it is running and line B is when it is cold.
Is this okay?

Sorry was hard to get a good picture of the site glass

Thanks

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Okay so the float needs to be reset to stay in the center at all time's regardless hot or cold.
As for the carb, is it a pressure thing or ?

Thank you.
 
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Float level should cause the needle valve to open/close as the demand varies to hold a normal level in the bowl.. The gas level should stay pretty much in the center of the sight glass under most normal conditions.--if it doesn't-- like when the engine is under heavy load, there may be some issue with the needle valve(plugged/contaminated) This would indicate a contaminated fuel delivery system--something restricting flow. Check the fuel filter-it should grab any contaminants before they get to the needle valve filter.
There may also be an issue with the fuel pump providing enough fuel for heavier loading(an indication it may be starting to go south)-make sure there are no telltale weeping leaks from the pump--if there are- need to change pumps asap, as the diaphragm rupture could dump fuel into the crankcase.
My .02
 

Stumpalama

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I think you may have missed something in you rebuild. It looks like the carb is leaking gas into the body when not running. Maybe you missed an o-ring or a piece of the float valve.
 
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First I want to thank you guys for your input as I am no carb guy and appreciate all the constructive suggestions given. With a manual I can do a pretty good job. We did strip and submerge the carb in carb cleaner for a few days prior to rebuild, and blew out all the orifices with filtered compressed air. The build was step by step with the manual but that does not mean we did not miss something. We had no parts left over so that to me is a good thing.
I checked the fuel filter and the pump. I will change out the fuel filter for RR purposes, but the pump looks fine on the external side.
We will pull the lid on top of the carb and check the bowl for restrictions and the power valve for smoothness. Also we will attempt the two part setting of the float again to see if we can get it to center at all times.
I also thought that it was leaking gas down into the body as Stumpalamea has suggested. What may cause this seepage? Bowl over filling? That maybe the answer to the shafts collecting residue after a week or so. As said when cold it shows around line B but when running and hot line A but never in the center. What started all of this was when driven for a bit sometimes after shutdown it would be a bear to start. At first we thought it was possibly the starter but we are starting to think definitely a carburetor situation. Again thank you and we are always willing to accept help.
 

Stumpalama

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If you drive it and let it set for a bit (a couple hours), come back, pop off the air cleaner cover and shine a light down the carb into the intake and check for fuel puddling in the intake or evidence it is dripping down the sides. I'm wondering about the fuel return line and if that is causing too much fuel pressure and resulting in the leaking. However, I'm fuzzy on the pump mechanics since it's been a while.
 
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Hi, just an update on a few things. Replaced the filter as it did have a few small floaters in it but not holding up the flow. Stopped by the local guru carb guy with 25 years of service and he feels as it is just an old carb that is a bit worn at the shafts and it to him is a norm for its age (30 years). He agrees with the drip check after shutdown but he said it is also something to be expected on a small amount for an old carb, rebuilt or not. Anything were it shows a bit of steam as it sits after shutdown is norm, but a lot of steam from the cold fuel hitting the inside of the base would be something to check.
So not sure what to think at this stage. Ohhhhh
 
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Some seeping is normal, but I'm not sure that yours is normal. Things that cause gas to drip on the butterflies make this worse, like plugged top cover vents, wicking of fuel out of the bowl and into the idle circuit and manifold leaks that require an increase in idle speed to compensate by pulling fuel out of the main nozzle at "idle". You may also have a leak at the gasket between the bowl and base.
 
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Thank you sir for the reply.
I am not to sure what a top cover vents you are referring to but I will try to investigate that. How would fuel wicker out of the fuel bowl?
I had checked the manifold with the old liquid check trick while running to see if it changes idle but seems as the manifold seals and parts are secure. I will have to check the upper gasket on the float bowl cover and see if it is in tack as you suggested. I believe that's what you are referring to when you say the gasket between the bowl and base.
I did pull the air cleaner off after a ten minute drive to see if fuel was pooling up or dripping but saw none.
That picture does show some concerns but this as said is several hundred miles of accumulation. Mow cleaned for monitoring.
Thanks

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Stumpalama

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It appears to be leaving from the mating surface of the carb body and the base as observed by @pinhead. There is evidence of it dripping down then spreading and probably being blown around., not necessarily from the rods themselves.
 
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That dirty stuff around the butterfly rods sure seems like there is a leak there---echo Stump(via Pin_Head) comments. That would also be a vac leak when running--
 
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Hate to waste all of your time. Not sure where to start now. I do appreciate the help. I still want to pull the lid off and see if the gasket is in good condition. I will get a better picture of the body areas to hopefully help. I did clean the rods so I could monitor any new build up, but so far nothing after about 25 miles. It is a good carb in the fact that it idles very well and has the power to take one up a hill and down the highway even an extreme angle when wheeling. No smoke, no real strong smells from the exhaust. I shut down the engine last night after a drive and looked at the float, it was down below the bottom mark on the site glass and never came up to the center. So I will be looking at the float settings today. I would think the float would be centered at all times.

Just wanted to add that I found what appears to be the same type of goo stain seen on the carb but down on the side of the engine block just below the intake/exhaust manifold. If thats the case the manifold must of loaded up with fuel and dripped down as some time???

I also found this interesting bit of information online. See attachment photo. Sorry a bit small to read.
http://www.thecarburetorshop.com/Troubleshooting.htm
I have been trying to avoid the ethanol fuels as much as possible but being the way things are it is virtuallyl impossible when away from your home town. This possibly may be the problem, not saying it is just possible. The non ethanol loclly I do find is 90 octane.

fuel ck.JPG
 
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We have had some good replies with good information on where and what should be followed up on with the issue of seeping or leaking at the shafts and the float setting. But after this last checking of the float and finding its internal settings to be as per Toyota manual says I am at a loss. All I can conclude is this was possibly a one time mass fuel seep after a long drive due to engine and outside temps causing a mass boil of fuel or wicking. We just need to keep our heads and eyes on the under hood items a bit more. As for the float when running its in the middle area and I guess that's a good thing.
The only other thing my brother and I found when following some of your suggestions was we pulled the choke out when warming up for the float check and at fully closed the carb sputtered and ran erratic. I believe that if anything that the carb should run at a max RPM and smooth. Well that is another issue but as of now all we can do is keep an eye on this area for signs of problems.
We wish to thank all you for your wonderful response in our search on this issue and will alert you if we find anything more. This is our hunting rig and want to make sure we get there and back with a prize we hope. Happy hunting.
Thank you
 

Stumpalama

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Not wasting anyone's time... we all love a riddle.
So, if you pull the choke at start up it runs rough? The choke is to richen the mixture i.e. reduce the amount of air, so that leads me to conclude you are already running rich at start up. Make sure you got your o-rings in place and the little rubber thingys on top of the venturi's within the carb body, they are easy to forget. if you lost one or both, a thin slice of vacuum hose does the trick. They set on top of the venturis and are visible when you remove the top of the carb. I would also make sure you got all the parts when you replaced the float needle valve. if you forgot the spring it won't operate correctly.
 
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Well okay if you like riddles, we just like the help.
I think I was going to say I will post a few more pictures of the float check so I better do as I said.
We used a 6mm screw wide driver that was perfect for the float height check, we let the float drop to take out any play and it was right on 6mm.
We used a 1.12mm wire as we could not find a 1.1mm (1.10mm) wire and eye balled the difference of 2 and seems to be pretty much on.
Checked all the 1st and 2nd slow jets to make sure they were on the correct sides (short and long) but it seems both were the same length?
Check all the other items that could be checked with lid off. Float bowl area is a bit of corrosion from the past but nothing floating around.
Main jets are open and clear and the brass one on pump side and chrome on other. I did blow off all debris and dirt before reinstall of all parts. Had to use the old gasket but it looks as if it would be up to the use. The pump bellow was with some cracks and splits but I would not think this would be a major issue other that dust and dirt getting it. Will try to find one. Float needle was clean and clear.

Posting more pictures
continued

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More pictures of float check:
Also if you see the venturi's I believe they have the gasket on the underside, not sure about o ring.
As for the choke it works fine at 3/4 out it the 1/4 more were it starts to sputter and lag. I think Pin_Head is on the right track, leave it alone if it works.
Well there you go as said very minor adjustments with no real change. OH did find the start of a drip stain from the manifold side again on the side of the engine block as before.?

Oh yes we wanted to ask about the 6mm settings. In our internet search we found on Toyota manual for the FJ40 series that said set the float at 7.5mm versus the 6mm. Anyone know of this difference? The other was still 1.1mm

Thanks guys

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Stumpalama

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Does the intake look oily inside? How about the air cleaner passage to the carb? It looks like you are missing the o-rings on top of the venturis though. Your carb rebuild kit should have come with a new power valve accordion seal.
 
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Does the intake look oily inside? How about the air cleaner passage to the carb? It looks like you are missing the o-rings on top of the venturis though. Your carb rebuild kit should have come with a new power valve accordion seal.
Not sure of the year, but my power valve does not have any 'accordion seal'
The 81 carb I rebuilt for install on my 77 does not have one either. Are you sure this is in reference to the power valve, and not the accelerator pump?
power valve1.jpg
power valve1.jpg
81 carb ac10.jpg
 

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