Two Buck Truck Carb Rebuild

[Two Buck]

I'm diving into the arcane and mysterious world of rebuilding the Aisan carburetor. I'll be posting pictures and questions as I go to ask for advice, serve as a cautionary tale to others, and document my progess as I either get my '85 FJ60 to pass the California smog test or go crazy trying.

First, let's meet the victim. I've had her for 10+ years and have alternated between daily driver and driveway ornament/spiderweb collector. This picture was taken in May of last year, when I was last taken with the urge to get it to pass smog. I gave up. Now I'm into it again. It runs okay once it's going, but won't start without being primed with carb cleaner. That plus the smog check failure makes a rebuild seem like a good option. Also, I kind of want to give it a try.

Let's see what we're working with here. Parked in my driveway since last May without moving, we've gathered some leaves. I guess I need to rake the engine bay.

Labeling hoses, pulling stuff off, removing the air cleaner... Looks like I need to rake that too.

Air cleaner off, granting "easy" access to the carb...

...and the carb is OUT. But what's wrong with this picture?

That hole's not supposed to be there. Or, rather, it is supposed to be there, but it should have a stud in it. And it did, but the stud wanted out.

Now the carb is out and is sitting on my workbench.

...along with the stud that wanted out. Not quite sure how I'm going to deal with this later.

One thing I'm concerned about is the mounting plate:

It has this linkage connect flange thing that looks pretty chewed up to me. Is this a problem?

So that's where we are tonight. I'll be taking the carb apart and cleaning it over the next few nights. Stand by for pix and questions...

 

[rover24]

You can heli coil that stud. I just did all my carb studs and the 2 where the egr goes into the manifold. The aluminum was stripping and I could never get a tight seal. Just make sure when you drill the carb studs to get all the metal shavings out of the intake.

 

[John McVicker]

You can heli coil that stud. I just did all my carb studs and the 2 where the egr goes into the manifold. The aluminum was stripping and I could never get a tight seal. Just make sure when you drill the carb studs to get all the metal shavings out of the intake.

Correct. And you might not need to do anything other than removing the stud w/vice grips and cleaning up the threads on the stud, as well as inside the hole.

John

 

[Spike Strip]

for the stud, just double-nut the bottom and remove the top nuts. Does not look like the threads are stripped. Just tighten it back down into the manifold using the double-nut method. Not too tight- Alum threads will strip very easily.

Plate for the linkage is fine. Just clean it and use good grease at all the pivot points when reassembling.

When disassembling the carb, find a nice big table to spread everything out on and have the manual and diagrams handy. Note - avoid taking apart anything with a spring attached to it as small parts may fly everywhere and you'll curse your mama's first-born when those parts go MIA. Ask me how I know.


Good luck.

 

[Two Buck]

Needin' some help...

Okay folks, I'm stuck already. Taking off the top cover of the carb, I have two issues:

• The power valve piston doesn't depress at all. In a video on rebuilding the Aisan carb I've been watching, it moves easily. So what's up with that?

• The needle valve seat won't break loose and my probably-should-be-bigger screwdriver is chewing it up a little. Should it be this hard to break free? And are there any suggestions how to get it loose without more damage (short of buying a bigger screwdriver)?

 

[Pighead]

Pull the power valve out, see what's on the other side.

You should have a new needle valve in the rebuild kit...take a vice-grip to the old one.

 

[Spike Strip]

Yes, the needle-seat is gonna be tight. Sealant. Grind down a screw driver 'til it fits. Grind the sides down too so you can use the same driver to remove the jets.

A lot of things are gonna be stuck, gummed up 'cuz the truck has been sitting for what, 8-10 years ?

 

[Two Buck]

Pull the power valve out, see what's on the other side.

You should have a new needle valve in the rebuild kit...take a vice-grip to the old one.

Good call on the needle valve in the kit. Forgot about that... 30 seconds with the vice grip and the old one is out. What was on the other side of the power valve was a black gummy mess. The top cover is soaking in the cleaner now.

A lot of things are gonna be stuck, gummed up 'cuz the truck has been sitting for what, 8-10 years ?

Ouch. It hasn't been THAT long. I drove it around the block two or three whole times when we were working on it last year!

 

[Two Buck]

Stuck again...

I'm still disassembling the carb. (Slow, that's me.) I got the top cover off and soaked it in carb dip overnight, now I'm working on the body. I'm trying to remove the accelerator pump retaining clip to get the ball out ("small ball/big hole") but I can't get a good grip on it and I'm not quite sure where to grab it to get a good hold -- and I'm concerned I won't be able to get it back in after.

So: Does anyone have any decent pics of this so I can get a better look at it? And if I proceed without removing the clip and ball -- will this defeat the purpose of rebuilding the carb even if I soak it overnight in the carb dip?

Thanks...

 

[FJ40Jim]

I'm trying to remove the accelerator pump retaining clip to get the ball out ("small ball/big hole") but I can't get a good grip on it and I'm not quite sure where to grab it to get a good hold -- and I'm concerned I won't be able to get it back in after.
So: Does anyone have any decent pics of this so I can get a better look at it? And if I proceed without removing the clip and ball -- will this defeat the purpose of rebuilding the carb even if I soak it overnight in the carb dip?

Yes, not completely cleaning out the AP circuit would be a mistake. That is one of the primary defects in the carburetor. The AP is inop, resulting in very hard (impossible?) starting.

 

[mwebfj60]

Quote: 'I'm trying to remove the accelerator pump retaining clip to get the ball out ("small ball/big hole") but I can't get a good grip on it and I'm not quite sure where to grab it to get a good hold -- and I'm concerned I won't be able to get it back in after.

That was the hardest part of the whole carb rebuild for me. That clip is kind of like the clip on a u-joint bearing. You have to squeeze it together and then lift it out. I used two scribes like a pair of tweezers to get mine out. Putting it back in was an even bigger challenge. If your power valve was all gummed up, I bet that little ball you are trying to get to is gummed up as well...along with the passages under it. Good Luck.

 

[Two Buck]

...That clip is kind of like the clip on a u-joint bearing. You have to squeeze it together and then lift it out. I used two scribes like a pair of tweezers to get mine out...

Thanks, that helps. I can't see it well enough to know if I'm even grabbing the right thing down there with my needlenose and I can't find any pictures of it online to show me what it looks like. Your description gives me an idea of how to approach it and what I need to do to get it out. I've been trying to pull out whatever I've been grabbing like a cotter pin, so I wasn't even close!

 

[Two Buck]

I'm trying to remove the accelerator pump retaining clip to get the ball out.

I figured out why I couldn't get that retaining clip out: It wasn't there. I fought with it for 20 minutes tonight trying to grab it with no luck, then I turned the carb over and the ball just fell right out. Go figure.

So now the body is soaking in the carb dip overnight. I'm moving at a glacial pace, but so far so good.

 

[Two Buck]

More questions...

Okay, everything's dipped and ready for reassembly, but I'm going to need to replace the missing retainer clip for the accelerator pump check ball for a whopping $3.03 at Specter. Fortunately, they're right down the road from me so I won't have to pay for shipping. Unfortunately, they're not open on weekends so I'll have to figure out a way to get away from work to go over there during the week.

I have two other parts that are questionable. The idle screw looks a little "screwy" to me, almost like it's bent. I don't think that's a problem, but I figured I'd ask all y'all. What do you think?

And the boot on the slow jet valve is falling apart. Specter doesn't even list the boot as a separate part and says the entire jet valve assembly is discontinued and no longer available. I'm thinking I can get away without replacing the boot since the rest of the assembly is in good working order. Can I? And if not, any leads on where to replace it?

Thanks for any advice...

 

[FJ40Jim]

Definitely replace the idle needle. When it is bent like that, the main part of the needle interferes w/ fuel flow, causing lean off-idle stumble.

Reinstall the SCV. The dust boot is just that: a dust boot. Non-critical.

Definitely get the missing check ball retainer. If the check ball was getting OOP and not shutting the hole, then there would be no AP action.

 

[stockhorse]

How is progress on the rebuild going?

 

[Two Buck]

How is progress on the rebuild going?

I'm moving at a glacial pace. Molasses in the winter in Alaska runs faster than I'm moving. But... I'm making progress. Thanks for asking.

Everything has been dipped and I'm reassembling it now. I may be jinxing myself in saying this before I'm done, but I don't get what the big deal is about rebuilding carbs -- it's like a jigsaw puzzle. If you just take your time and put everything back where it came from, I don't see what's so hard about it. (I really hope I don't regret that...)

The b!tch-kitty so far has been that stupid retaining clip for the check ball in the accelerator pump. I got a new one today from $OR. I fought with it for 20 minutes to get it in, and then there was a little >>plink<< sound and it wasn't there anymore. Disappeared. It somehow sproinged its way out of the big hole and went flying God knows where in my garage.

I finally gave up looking for it after crawling around on the garage floor for half an hour -- and of course I finally saw it as I was walking away. I eventually got it in place, but that was rough.

So here's a picture of the dang thing for anyone reading this thread two years down the road. It would have helped me immensely to know what it looked like when I was trying to pull it out when it wasn't even there. I had to bend and squeeze it down to about half this diameter to get it in, but it seems to be in solidly now.

Now I'm bolting all the clips and mounts and other hoo-hah back in place. This is where taking all the pictures at the start would be coming in handy if I were looking at them. I've given up for the night after trying the same clip in three different holes. I'll start up again tomorrow night -- and I'll have the pictures with me.

It should be good to go and ready to install back in the truck tomorrow. At that point I'll address the next issue: that stupid helicoiled stud that de-helicoiled itself. Stand by for questions on that...

 

[mwebfj60]

Pics

Let me know if you need pics of any of the linkage/parts for reassembly, I have a pretty good amount of them from my recent rebuild.

 

[Pdwight]

Sounds like you have it

You are right rebuilding carbs is not rocket science , it more a note taking housekeeping procedure. Get a well lighted work bench cover it with an old white sheet so you see tiny parts (they dont bounce off fabric as well as a hard counter top) and take your time. I just did this to my 78FJ and it went very well. I used a Horrible freight ultrasonic cleaner to do my parts is a dilution of Dawn and simple green and it really cleaned up well.

 

[Two Buck]

Progress report

The carb is all back together again. Figuring out the linkages was a bit of a puzzlement but I think I sorted it all out. Here's a couple of pics; if anyone sees anything out of place, feel free to say so:

My next challenge is the mounting stud that came out when I pulled the carb from the engine. The bolt took what looks to be a helicoil insert out with it and the hole is smooth with no threading.

I've never dealt with something like this before, so I'm looking for advice from all y'all. How would you handle this?