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patate657

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I finally got the carbs done and installed. Everything inside looked good. Had them in carb cleaner. Rinsed them out real good. Blew everything out and sprayed everything in and about with carb cleaner. Cleaned and soaked the little manifolds in each carb also and replace the gaskets and the little O-ring. I changed 2 0-rings and the float needle on each carb. I removed the copper slide for the needles and cleaned them too. Saw one that I had installed incorrectly last time and fixed that. Cleaned and checked the slides/Diaphragms, all good. Had replaced them about 2 months back with the first time I took them apart. Got it installed back on the bike and 'Finally' got the bike to start. Runs / starts, 'NOW', okay with a bit of popping. This is all without the airbox installed. The reason I mention the air box is because I was told here that these bikes do weird stuff with the air box off. Now my question is, Will syncing the carbs straighten all that out (With the air box and filter back on of course)? Don't think they've ever been synced.
If synchronizing doesn't mellow it out, should I go back in the carbs and do something else? Any advice will be appreciated....;)
 

Fire-medic

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Replace the airbox and its lid.

Ensure that the carbs are fully-seated on the rubber donuts on the bottom. Fully-tighten the clamps.

Ensure that the airbox is fully-seated on the top-side of the carbs, to the rubber donuts. Tighten the clamps. Replace the airbox lid, screw it down. Then try to get it running for tuning for carburetion synchronization.

Here's something from an earlier post:

There's an easy way to get your airbox mounted and this is how:

Assuming your rubbers are in decent shape, no rips, tears, or cracks which would cause leaks, simply place the assembled airbox above your carbs. Start them onto the carb bellmouths. Now you need to have the bike on the centerstand. Step onto the footpegs and move your position forward until your butt is resting on the airbox lid.

Gently lower your weight onto the airbox lid, and you should feel your airbox pop-into the carb bellmouth rubbers. Climb off and confirm that your airbox is now in-place. You can use some water-soluble gel like KY (yes, that KY) and place a thin film onto the inside of the rubbers and the mating airbox surfaces to help 'mate' the pieces (no pun intended). Remember to replace the KY where you got it from.

This works for me with older rubbers when you cannot seem to get them to fit. Some people say, "boil them in water to soften them up, and quickly place them into position, and press the airbox down." I bet that if you try the persuasion of your butt on top of the lid, you won't need to boil the rubber rings.

I call it the Happy Days Method: "sit on it Potsie!"

(10) Pods? New air box? | Page 2 | Yamaha Star V-Max VMAX Motorcycle Discussion Forum (vmaxforum.net) Post #32
 
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patate657

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Replace the airbox and its lid.

Ensure that the carbs are fully-seated on the rubber donuts on the bottom. Fully-tighten the clamps.

Ensure that the airbox is fully-seated on the top-side of the carbs, to the rubber donuts. Tighten the clamps. Replace the airbox lid, screw it down. Then try to get it running for tuning for carburetion synchronization.

Here's something from an earlier post:

There's an easy way to get your airbox mounted and this is how:

Assuming your rubbers are in decent shape, no rips, tears, or cracks which would cause leaks, simply place the assembled airbox above your carbs. Start them onto the carb bellmouths. Now you need to have the bike on the centerstand. Step onto the footpegs and move your position forward until your butt is resting on the airbox lid.

Gently lower your weight onto the airbox lid, and you should feel your airbox pop-into the carb bellmouth rubbers. Climb off and confirm that your airbox is now in-place. You can use some water-soluble gel like KY (yes, that KY) and place a thin film onto the inside of the rubbers and the mating airbox surfaces to help 'mate' the pieces (no pun intended). Remember to replace the KY where you got it from.

This works for me with older rubbers when you cannot seem to get them to fit. Some people say, "boil them in water to soften them up, and quickly place them into position, and press the airbox down." I bet that if you try the persuasion of your butt on top of the lid, you won't need to boil the rubber rings.


I call it the Happy Days Method: "sit on it Potsie!"

(10) Pods? New air box? | Page 2 | Yamaha Star V-Max VMAX Motorcycle Discussion Forum (vmaxforum.net) Post #32
Thank you
 

02GF74

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hmmm, your list of things done does not mention you took the jet block off and checked the tiny hole in the pilot jet was clear. (that is the Achilles heel of these carbs)
 

patate657

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hmmm, your list of things done does not mention you took the jet block off and checked the tiny hole in the pilot jet was clear. (that is the Achilles heel of these carbs)
Don't know terms correctly. May have done it. Show me a pic please if possible? Or point it out in this pic.
P7040020.JPG P7040021.JPG P7040031.JPG
 

02GF74

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OK, second photo shows the jet block under the thumb, and third photo has the block removed.

There are 2 rubber bungs, removing them allows access to the emulsion tube and pilot jet to be unscrewed. Once the pilot jet is out, the tiny hole through it needs to be clear. The holes in the emulsion tube are much bigger so unlikely to be an issue.

Whether ultrasonic cleaner will clean a blocked jet I don't know, mine were blocked pretty solid with a varnish like substance that required much poking with a sharpened needle.
 

Parminio

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and the float needle on each carb.
That was probably a mistake you made.

The vast majority of kits have float needles that the rubber is far too large on and it restricts the fuel flow. If you still have your old factory needles, pull one of the new ones out and compare it. If you see that the rubber part of the new ones looks much fatter and has a lower angle than the old factory ones, put the old factory ones back in.

That difference isn't down to wear. It's down to being the wrong needle valve.
 

maleko89

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OK, second photo shows the jet block under the thumb, and third photo has the block removed.

There are 2 rubber bungs, removing them allows access to the emulsion tube and pilot jet to be unscrewed. Once the pilot jet is out, the tiny hole through it needs to be clear. The holes in the emulsion tube are much bigger so unlikely to be an issue.

Whether ultrasonic cleaner will clean a blocked jet I don't know, mine were blocked pretty solid with a varnish like substance that required much poking with a sharpened needle.
Make sure rubber caps are soft and soak them in fuel while working on the block. For the pfj’s, making sure carb cleaner exits the outlet is a good sign.
 

patate657

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Yes that's what I called the manifolds. They remind me of little manifolds. Each one was removed and soaked. Holes sprayed and cleared. Couldn't find my ultrasonic cleaner, so had to do it the old way, with time in the Heavy Duty carb cleaner.
 

patate657

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'There are 2 rubber bungs, removing them allows access to the emulsion tube and pilot jet to be unscrewed. Once the pilot jet is out, the tiny hole through it needs to be clear. The holes in the emulsion tube are much bigger so unlikely to be an issue.'
This I didn't do, but I did remove the bungs before soaking. If I need to remove the carbs again, I'll be sure to check them. Thanks
 

DreamV4

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People pretty often miss cleaning idle jet and 4 holes in wall of a carb.
 

desert_max

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Yes that's what I called the manifolds. They remind me of little manifolds. Each one was removed and soaked. Holes sprayed and cleared. Couldn't find my ultrasonic cleaner, so had to do it the old way, with time in the Heavy Duty carb cleaner.

Yeah, if you did not physically remove the pilot jets from the jet block, they will not be clear. You will have trouble. In my opinion, it would be worth removing the carbs again just to do that. Ultrasonic action will not clear those rascals.
 

patate657

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Yeah, if you did not physically remove the pilot jets from the jet block, they will not be clear. You will have trouble. In my opinion, it would be worth removing the carbs again just to do that. Ultrasonic action will not clear those rascals.
Can you tell me an easy way of inserting the float together with the float needle?
 

Fire-medic

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The obligatory pilot jet w/wire pic.

Then, no probe/wire.

A float valve seat.

Show us which needle you have.

VMax pilot jet.jpg VMax pilot jet lighted.jpg VMax needle valve seat.jpg VMax needles.jpg
 

02GF74

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Can you tell me an easy way of inserting the float together with the float needle?
Strange as I didn't find this hard to do. Tip the carb so the needle valve drops in, lay carb down so it's horizontal, rotate the little wire so the open end is uppermost, drop in fit the float ensuring the tang locates in the wire gap.

Beware of aftermarket needle valves, one owner on here found the small wire catching on the carb body so it would not seal.
 

patate657

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When I went back in, I noticed 2 of the float needle retainers that hangs them on the float were missing. I made sure the new ones where installed correctly. I was able to do it with a curved ice pick thingieee. Hoped there'd be an easier way....🤷‍♂️
 

02GF74

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You're in luck, I managed to find a photo of a disassembled jet block. Assuming the parts are laid out in order, it is the leftmost tube, with the smaller rubber bung.

The brass parts laid beneath the block are pilot jet, emulsion tube (this has holes drilled in the side).

To undo the pilot and emulsion jets, use the largest flat blade screwdriver that fits in the hole with the thickest end so it fits tightly in the slot to minimise risk of chewing up the jets.
Screenshot_20210706-192410.jpg
 

Fire-medic

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Yep, that's a good pic.

I'm no great wizard with the repairs, but I've never found it very-difficult to get the float needle valve into its seat. A small screwdriver or a pick is OK, but I've also just been able to do it with my fingers, without much difficulty, and my fingers are more like sausages than needles.

VMax carb float area.png
1986 Yamaha V-MAX 1200 (VMX12S) Carburetor | Ron Ayers
 
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