O & R Carb Repair Tutorial

[JUST O&R 237]

I can do that.

[Sharri Dandy 5]

Followed the guide above but used a piece of feeler gauge instead of floss. Everything slides right in. Held my breathe when the spring dropped down and hit the arm. Might attempt to make a spare spring out of the 0.003" feeler. Happy days!

[factory 487]

On 5/19/2020 at 11:40 AM, Sharri Dandy said:

Followed the guide above but used a piece of feeler gauge instead of floss. Everything slides right in. Held my breathe when the spring dropped down and hit the arm. Might attempt to make a spare spring out of the 0.003" feeler. Happy days!

 

Good to hear it worked out.

 

David

[Wallfish 698]

On 5/19/2020 at 6:40 AM, Sharri Dandy said:

Followed the guide above but used a piece of feeler gauge instead of floss. Everything slides right in. Held my breathe when the spring dropped down and hit the arm. Might attempt to make a spare spring out of the 0.003" feeler. Happy days!

That's exactly what I've been doing recently. Before I would leave the roller behind the groove it sits in to hold the ends of the spring up instead of using a string, then use a pic tool to move the roller up into it's proper place after the spring is in. BUT, by far using a thin piece (of anything) like that is the easiest and quickest method for installing that spring.

[factory 487]

For the last couple of carb rebuilds I've used a piece of gasket paper for sliding the spring over the roller, the gasket paper has also been used to set the coil gap at 10 thou.

 

David

[art faulkner 0]

need the ball for the carb, what size is it 3/32??

[CNew 404]

Some carbs use 1/16” and some use 3/32”.

[art faulkner 0]

the motor  type 127, there is number 2 on the internal of the  housing, the tutorial with the paper assist insertion of the spring shows a number one. I notice the spring was upsidedown, comparing to the paper assist tutorial, and no ball. I think its a 5/32 ball,,change the valve diaphrams also?? if you have the parts bill and send tks art

Edited August 14, 2020 by art faulkner
3/32 not 5/32

[art faulkner 0]

3/32 not 5/32

[art faulkner 0]

amazon has 100  3/32 chrome steel  balls for $5.95

[JUST O&R 237]

That's what most of us do I think we all have a 50 year supply

[art faulkner 0]

I thought it was closer to a hundred, you have to pay $10.00 for a diaphram, so $5.95 for a 3/32 ball, such is life

[factory 487]

On 8/14/2020 at 2:22 AM, art faulkner said:

the motor  type 127, there is number 2 on the internal of the  housing, the tutorial with the paper assist insertion of the spring shows a number one. I notice the spring was upsidedown, comparing to the paper assist tutorial, and no ball. I think its a 5/32 ball,,change the valve diaphrams also?? if you have the parts bill and send tks art

 

I don't think the number 1 or 2 on the casting means anything useful, just looked through some of my pictures and have found both numbers used on early side needle valve carbs with the small 1/16" ball bearing.

Not sure what you mean about the spring in the paper assist post as it isn't shown in the final position.

 

If your engine has clear check valve diaphragm then it's probably OK, if it's the black rubber material (as used for the main diaphragm) then they do go bad, I've even had one where the part of it was completely missing.

 

David

[CNew 404]

3 minutes ago, factory said:

 

If your engine has clear check valve diaphragm then it's probably OK, if it's the black rubber material (as used for the main diaphragm) then they do go bad, I've even had one where the part of it was completely missing.

I came across one of these for the first time just recently, ended up replacing it with a plastic check valve.

[factory 487]

They are quite commonly found with the earlier engines.

 

On 8/14/2020 at 5:48 PM, art faulkner said:

I thought it was closer to a hundred, you have to pay $10.00 for a diaphram, so $5.95 for a 3/32 ball, such is life

 

That's what you get with mass production and some of those chromed steel balls come pre-rusted (picture from eBay).

 

The diaphragm kits are made in small batches, just be thankful they are available at all, I can't imagine the material is cheap either.

 

David

[art faulkner 0]

I could have bought 316ss 10 for $17.00 however I opted  for the chrome, they in a very non-corrosive environment, and should last. I like the change in the diaphragm arm where a rubber tip is used, rather then the ball.. I will receive the chrome balls next week and if rusted will return, tks for the warning My tiny tiger and type 133(olive drab color) are running excellent. the  type 127  is the one I am working on.

[MajorH 0]

@Webhead  I've tried msging you a few times but the system won' let me for some reason.  Anyways, do you have any diaphragms for sale still?  Can you send me the cost?

[MajorH 0]

Any guesses on why my carb won't prime?  I've tried the build with and without the large diaphragm's gasket (2 came in the ebay kit).  I've tried with a half turn and with a turn and a half of the needle.  It just doesn't want to pull vacuum.

[MajorH 0]

Here's the upper carb body

 

 

 

The lower carb body:

 

The carb:

 

 

 

 

[CNew 404]

I wonder if the internal induction seals are leaking and letting air past so not creating the vacuum.

[MajorH 0]

So I tried blowing air into the inlet and you can only blow air when you push the button.  When I try to suck air the other direction, it won't pass at all regardless of the button.  

[CNew 404]

That is odd, initially I was thinking maybe the little aluminum disc that contacts the primer button and lever arm might not be making good contact but since you’re able to blow air that must be working. Still scratching my head…

 

I think this is a one-way valve, so you should be able to blow air with the button pushed down but Not sure you should be able to suck air. That little steel ball would seat in the hole I think and prevent air from passing when you’re sucking. I might have to see if I have a working carb somewhere I can play with to test this idea.

Edited December 18, 2022 by CNew

[Wallfish 698]

On 12/17/2022 at 9:33 PM, MajorH said:

Any guesses on why my carb won't prime?  I've tried the build with and without the large diaphragm's gasket (2 came in the ebay kit).  I've tried with a half turn and with a turn and a half of the needle.  It just doesn't want to pull vacuum

Try connecting fuel line to the tank port that goes to the carb. With fuel 1/2 filled in the tank it should bubble air when you blow into it. Need to verify it's connected to the correct port and that complete fuel line is open and not clogged

If it bubbles try directly priming fuel into the carb or pour some in the plug hole so it starts. Watch the fuel line to see if it pulls fuel up now because it's running. <ight need to repeat a couple times

[MajorH 0]

I did this and there were bubbles.  I also used a fuel removal tool through the port and was able to suck fuel out, so there's no real issue there. 

 

I took apart and reassembled the carb again to give it another clean.  Once connecting it I was able to get some priming. I put it all back together and gave it some pulls and the engine starts to run for about 2 seconds then runs lean/dry and quits.  A few more primes and a few more pulls and it'll do the same thing.  So it'll run but won't continue pulling fuel.  Is this indicative of the needle not being properly adjusted?  

 

Second question, how tight do the other two fuel ports need to be sealed to one another?  Do they need to be airtight, or can the tube sit on them somewhat freely?

[Wallfish 698]

1st question --Assuming you installed a new diaphragm so could be. So start with about a 3/4 -1 turn on out the needle. Use the primer button to keep it running while adjusting if it's stopping because of fuel starvation.

Leaking case seals can affect the vacuum pulse pressure the diaphragm uses for the pressure to pump fuel.

 

2nd question. Not a big deal. The ports are ONLY there to allow fuel to fill up into the raised hump opposite the fuel fill. Without it, an air bubble would stop the fuel from entering that portion of the tank. The fuel line simply connects the 2 ports so fuel doesn't spill out