Wanted carb parts

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longtrail

longtrail

10 Year
Joined
Jun 1, 2013
Threads
4
Messages
78
Location
Wyoming
Location
United States
bigball2.jpg


I'm looking for two parts from the photo- the aluminum looking stopper and the small black gasket below it.
My carburetor is the oem 1974 aisan. I believe these parts are the same in '69 to '74 models. The FSM isn't particularly helpful in naming these parts, just list them as 'stopper' and 'gasket'. The rebuild instructions list it as 'pump passage stopper'.

Anyone?
 
I suspected that it might but wasn't sure. Too bad that's not the case for the stopper. May have to buy an entire parts carb for that one little piece...
 
Form follows function. I would file a nail down to perform that function if I didn't have access to some. I stopped selling carb parts like that years ago to make sure I could supply my in-house rebuilds.
 
In case you haven't seen what the gasket looks like in person, it is flat. Like a rubber garden hose washer, but smaller. I would guess a good Ace hardware store might have something that would work. Perhaps even a round o-ring would work.

An important detail on your rebuild is, make sure the air horn mating surface is not too warped. And don't overtighten your sight glass screws, if you do and yours is actual glass, it WILL crack.
 
To add to what @thebigredrocker posted, the two things can be related. If the rubber gasket is too thick, it can keep the air horn from sealing properly, contributing to warping the air horn. Unfortunately,This is not academic . A fair number of gaskets supplied in rebuild kits are exactly that: too thick.

What makes matters worse is that THAT chamber is right next to the slo-jet that supplies fuel to the idle circuit. So if the gasket keeps the air horn from mating to the fuel bowl, it's also very likely to induce a vacuum leak that disrupts the idle circuit.

Best

Mark
 
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Mark & Redrocker- thanks for the advice and suggestions, looks like I'll have to get creative with this! Does the gasket just sit on top of the stopper or does it wrap around the flat part and create kind of a seal?

Mark, I left you a voicemail the other day, disregard. I wish I'd sent this carb out to you for rebuild. I had a local guy do it and here I am, still mucking around with it months later.

One more question, could these missing parts contribute to an off idle/acerlation stumble? It starts and idles great, but I get a major stumble and rough acceleration going down the road. I've checked the idle solenoid and accelerator pump and they seem to be working properly. I've also been following some other threads, namely the 'unfindable vacuum leak' trying to troubleshoot this issue. Can't find any vacuum leaks and I get a very steady 19 in with my vacuum gauge.
 
Is your accelerator pump actuating promptly? It should be as horny as an adolescent male: ready to squirt on a moment's notice.

Edit:damm auto-correct.
 
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ah, I don't think anything on this old cruiser responds on a moments notice:D She likes slow and steady with plenty of patience ....except when i first change gears and am cruising slowly, then its rough and sputtering. I can floor the gas pedal and kind of power through the roughness sometimes though.

I don't know what an account pump is. I get a solid stream of fuel though when I pump the accelerator. I even added a couple washers to the pump lever spring, to give it a little more tension.
 
so I took the top off the carb again and put a straight edge on the air horn mating surface. It is not perfectly flat, I can see light between the edge and the surface on two sides. On the worst side I could probably slide a piece of paper through the gap.

I used the rivet idea to make a stopper and found a tiny gasket from ace hardware (thanks redroccker!) and reassembled the carb. No change in my problem, I'm still getting hesitation on acceleration. Any hope for this carb or is it a goner? Stacking two gaskets between the air horn and carb body probably not a good idea? With the carb assembled and running, I can see the air horn gasket become 'wet' but not actually leaking. Is this warped air horn possibly causing my rough/hesitation on acceleration?

*re-reading this thread, anyway to move it to the tech forum?*
 
thebigredrocker said:
Any luck?
Click to expand...

Afraid not. It is such a frustrating problem too. It starts and idles great (with good 19" of vacuumtoo), unless it's been sitting for a while and then I only have to pump the gas a couple times. The fuel will drain out of the bowl after a couple days of sitting but this seems to be a common occurrence with these old carbs and not necessarily a problem.
Going down the road there is an initial hesitation/stumble after changing gears and accelerating. If I keep the choke pulled out about a 1/4 of the way I can minimize/eliminate this hesitation. Once I get past this initial stumble, it accelerates great. I do not need any choke to idle smoothly though.
I've turned my attention to the distributor again, as retarding it seem to minimize the stumble slightly. I've swapped out the points a couple times. I'm wondering if the weights inside are sticking? I'm reading that the '74 dizzy's are not the greatest and known for various problems. I've had this dizzy out and disassembled but perhaps I missed something....I'm about ready to throw in a new dizzy...
 
Indygbd said:
I have a pile of carb parts and a bag full of oem gaskets. If you need anything let me know.
Click to expand...
Awesome, thanks! I might need the horn/body gasket eventually if I end up taking the horn off again. The gasket in there now is not old, but I've had the carb horn off so many times that it is starting to look quite compressed and worn.
 
pardion said:
Have you tried the old mechanics carb trick of sanding your air horn or body surfaces flat? A old flat window glass, and a sheet of fine emery paper and sand the mating surfaces flat again to eliminate that vacuum leak.
Click to expand...

There's that pesky protrusion that the float hangs from.
 
longtrail said:
ah, I don't think anything on this old cruiser responds on a moments notice:D She likes slow and steady with plenty of patience ....except when i first change gears and am cruising slowly, then its rough and sputtering. I can floor the gas pedal and kind of power through the roughness sometimes though.

I don't know what an account pump is. I get a solid stream of fuel though when I pump the accelerator. I even added a couple washers to the pump lever spring, to give it a little more tension.
Click to expand...

Did you put washers on top of the accelerator pump spring, but "under" the arm itself? If so, move the washers on top of the arm, cotter pin will now be in contact with washers. "Longer stroke" is what you are trying to acheive, not necessarily spring tension.

Do you have a vacuum gauge mounted in your cab? If not, maybe lengthen your handheld gauge to reach.

120 main jet?
 
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Swapped out the washers as suggested, thanks, but no fixie. Don't have the vacuum gauge mounted inside, but I've been considering it. I'd have to find an inconspicuous spot to mount it. I do hook it up on a regular basis to see if any of the changes I've done affect anything. The jets are factory and looked great when I pulled them out, I had the fsm handy when I looked at them.
I know throwing money at it without identifying the problem is not the best way to go, but I'm at a loss. I just ordered the non-usa dizzy from toyota, hopefully that will solve my issue.

Something else I've noticed with this problem that may shed some light- while in neutral if I tap the accelerator lightly a couple times I can get past the stumble and rev it up no problem. Also, if i rev it VERY slow I can also get past the stumble. 'Normal' revving or acceleration and then i get the hesitation/stumble that will sometimes kill the motor. Under load makes it worse.
 
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