Carb Neck Repair on a OS Carb for a GS racing vision pro nitro car

[gandalfnz]

Hi Fellas

I have had this car for over a year, and is the only nitro I just couldn't get going and figure it out. The car looks brand new, engine too!
Basically, it starts, and runs lean all the time, from mid to high sounds ok, but as soon as the RPM drop, it will just shut down.
Long story short, I have always suspect its the Carb that was the issue, and have shelved the car until suitable and cost effective replacement could be found.
I then received an OS carb in one of the nitro bundles I purchased online, and as you can see from the pic it someone tightened the pinch bolt too much and broken the carb neck.
Knowing how good and expensive OS carbs are, I was reluctant to throw it away, and am attempting to give a second life.
As you can see, I used some JB weld steel 2 part epoxy and have filled and sanded the broken part nicely.

I am interested in hearing whether you think that this carb repair will work, and if anyone else has a better idea?

Thanks

 

[Greywolf74]

Good luck with that repair.

 

[gandalfnz]

Good luck with that repair.

Thanks, it would have been better to make another 0.5 mm metal insert, but I don't have a lathe. YET!

 

[TRAT]

Hope it works for ya.

 

[tudordewolf]

Looks as good a job as anyone could do, the only downside I see is that the pinch bolt will be applying its force directly to the repair, so you'll either have to be pretty gentle with it or use a little sealant to kinda glue it in.

An Sh. 18 slide carb is under $20 and would be a drop-in replacement, just a thought.

 

[gandalfnz]

Looks as good a job as anyone could do, the only downside I see is that the pinch bolt will be applying its force directly to the repair, so you'll either have to be pretty gentle with it or use a little sealant to kinda glue it in.

An Sh. 18 slide carb is under $20 and would be a drop-in replacement, just a thought.

Hi

Yes, super gentle is the key, wish I had a lathe to insert a 0.5mm piece from the inside of the neck.
I love OS carbs, they are just so good and quality made.
Are you talking about the SH carbs on amain hobbies store?

 

[tudordewolf]

Hi

Yes, super gentle is the key, wish I had a lathe to insert a 0.5mm piece from the inside of the neck.
I love OS carbs, they are just so good and quality made.
Are you talking about the SH carbs on amain hobbies store?

I definitely agree that the OS carbs are the Rolls-Royce of their type, I'm eager to swap as many of my engines with them as I can, but I'd tentatively make a case for function over form if that one's giving you trouble.

I'm yet to break in the 11k I put on my TRX 3.3, I just admire it now and then... I picked up a 10E (without the holes in the neck) to put in one of my small-blocks, still picking a winner.

Yeah, the SHETE1809B.

The original carb on the GS .18 looks almost exactly like it, I happen to have one on the shelf. I actually think they may be the same carb:

 

[gandalfnz]

I definitely agree that the OS carbs are the Rolls-Royce of their type, I'm eager to swap as many of my engines with them as I can, but I'd tentatively make a case for function over form if that one's giving you trouble.

I'm yet to break in the 11k I put on my TRX 3.3, I just admire it now and then... I picked up a 10E (without the holes in the neck) to put in one of my small-blocks, still picking a winner.

Yeah, the SHETE1809B.

The original carb on the GS .18 looks almost exactly like it, I happen to have one on the shelf. I actually think they may be the same carb:

View attachment 157901

Man, that GS18 engine has given me so much headache, could not figure it out, in the end I decided it must be the damn carb.
Yet, that is the exact same engine and carb like mine.
Where did pull that one from?
Pretty sure that whole GS racing brand/car is just a copy of HPI's RS4 line up.

 

[tudordewolf]

Man, that GS18 engine has given me so much headache, could not figure it out, in the end I decided it must be the damn carb.
Yet, that is the exact same engine and carb like mine.
Where did pull that one from?
Pretty sure that whole GS racing brand/car is just a copy of HPI's RS4 line up.

I got it on ebay for ~$60, seemed like a good deal, figured I'd have something to drop it into sooner or later. Might try to make it work in a FFish. I kinda fell for the monogrammed cooling head to mean "fancy"

 

[gandalfnz]

I got it on ebay for ~$60, seemed like a good deal, figured I'd have something to drop it into sooner or later. Might try to make it work in a FFish. I kinda fell for the monogrammed cooling head to mean "fancy"

I dont know man, I mean this is one of the best looking nitro cars I own, but when it comes to quality, I am gonna have to see once I get it to actually work.
Great looking body that came with it.

 

[alfredwong2003]

They could look the same from the outside, but the shape of the needle could be very different.

 

[tntpoof]

JB weld on carb neck hole. to compare carb needles do the old shadow test. shine a light Infront of 1 then draw around shadow on wall with paper underneath .then do same to other. keep light at same distance along with needle. Use a light behind outlines to see difference between them.

 

[gandalfnz]

They could look the same from the outside, but the shape of the needle could be very different.

Tue that. Cheers

JB weld on carb neck hole. to compare carb needles do the old shadow test. shine a light Infront of 1 then draw around shadow on wall with paper underneath .then do same to other. keep light at same distance along with needle. Use a light behind outlines to see difference between them.

I am not sure I fully understand this, I have just woken up, I will have to re-read again. Thank you!

I am happy to report that the carb neck repair has been a success, tightened the pinch bolt lightly, carb does not move at all, and seals nicely. No air leaks.
Now onto testing once the weather clears.

 

[gandalfnz]

Ok, problem is still there, maybe to a lesser extent.
Just unable to tune it, its either too rich or too lean with small needle increments....
Really dont know what else to do.
I am now thinking that maybe engine was not broken in properly when it was brand new.
Might just bin it...and put a TRX 3.3 in it, since it needs a rear exhaust engine.

Thanks

 

[gandalfnz]

Is someone able to help me for an exploded view of the OS 10C carb?
I need to confirm how LSN should look like on this carb, maybe that is the reason I am unable to tune correctly.
LSN does not seem right, theres no needle as per se, I think I this carb might be fault as well, haven't even noticed this until now.
It all makes sense, since I am not able to tune bottom end, no matter how much I adjust the LSN.

OS 10C

Cheers

 

[gandalfnz]

So it turns out that the carb I repaired had an LSN insert missing.
All that work for nothing. Oh well.
Serves me right for not inspecting properly, although the LSN is designed in a unusual way.

This was completely missing.

 

[fernando mateus]

Hi Fellas

I have had this car for over a year, and is the only nitro I just couldn't get going and figure it out. The car looks brand new, engine too!
Basically, it starts, and runs lean all the time, from mid to high sounds ok, but as soon as the RPM drop, it will just shut down.
Long story short, I have always suspect its the Carb that was the issue, and have shelved the car until suitable and cost effective replacement could be found.
I then received an OS carb in one of the nitro bundles I purchased online, and as you can see from the pic it someone tightened the pinch bolt too much and broken the carb neck.
Knowing how good and expensive OS carbs are, I was reluctant to throw it away, and am attempting to give a second life.
As you can see, I used some JB weld steel 2 part epoxy and have filled and sanded the broken part nicely.

I am interested in hearing whether you think that this carb repair will work, and if anyone else has a better idea?

Thanks

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Your Best shot is you file you make kind of a cone shape towards the inside of the carburetor the outside being bigger you put something on the inside to stop epoxy from going in and that's it they make epoxy for high temperature and also for aluminum

 

[fernando mateus]

Hi Fellas

I have had this car for over a year, and is the only nitro I just couldn't get going and figure it out. The car looks brand new, engine too!
Basically, it starts, and runs lean all the time, from mid to high sounds ok, but as soon as the RPM drop, it will just shut down.
Long story short, I have always suspect its the Carb that was the issue, and have shelved the car until suitable and cost effective replacement could be found.
I then received an OS carb in one of the nitro bundles I purchased online, and as you can see from the pic it someone tightened the pinch bolt too much and broken the carb neck.
Knowing how good and expensive OS carbs are, I was reluctant to throw it away, and am attempting to give a second life.
As you can see, I used some JB weld steel 2 part epoxy and have filled and sanded the broken part nicely.

I am interested in hearing whether you think that this carb repair will work, and if anyone else has a better idea?

Thanks

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I'd like to know did it works okay. I use epoxy in a lot of stuff and always works for me