Question about pressed in carb seats

[Captndrydock]

My TC carbs have pressed in seats and I've often wondered if there is a rubber needle seat in there? Can they be replaced with a screw in seat for better preventative maintenance?

 

[Nordin]

I do not know about that.
You have to check the schematic for your engine.
Actually I never do anything to the inlet valve needle more than clean it with carb cleaner after I have had them in my Finsonic (same as Ultrasonic cleaner but another brand) cleaner.
Then I blow the carbs with compressed air.
Never have had an issue with leaking carbs due to bad seats or torne needle tips.

 

[jerryjerry05]

My TC carbs have pressed in seats and I've often wondered if there is a rubber needle seat in there? Can they be replaced with a screw in seat for better preventative maintenance?

The needle comes in 2 styles.
#1 is a solid needle.
#2 is a needle with a rubber tip molded into the needle.
#1 seat: has a teenie tiny o-ring in the base of the seat.
#2 seat: is solid.

The #1 seats o-ring can rip/tear or swell( that can be difficult to diagnose) when certain chemicals are used.
Most that swell go back to normal after exposure to air for a few hours.

Close up pics always help.
Not many have luck when removing pressed in seats.

 

[Captndrydock]

Thanks for the info Jerry! Here's photo I happen to already have. Not sure if that's close enough. I'll investigate further and take another one later.

 

[Captndrydock]

But mine does have the solid needle, so I guess that means there's a tiny O ring in there. It's from a1977 135 hp. I'll be more careful about using carb cleaner going forward. I have another set of TC carbs out of a 1980 115hp and I'm pretty sure they have the rubber tipped needles. I'm inclined to think that's preferable.

 

[Captndrydock]

I just looked and the carbs with rubber tipped needles do seem to have bare metal seats. The carbs on my boat with metal needles are still installed and seem to be working fine, so I'll just leave well enough alone. I appreciate the info though, something I've had in the back of my mind for a while.

 

[Captndrydock]

I do not know about that.
You have to check the schematic for your engine.
Actually I never do anything to the inlet valve needle more than clean it with carb cleaner after I have had them in my Finsonic (same as Ultrasonic cleaner but another brand) cleaner.
Then I blow the carbs with compressed air.
Never have had an issue with leaking carbs due to bad seats or torne needle tips.

Good to know that carb cleaner doesn't necessarily destroy the rubber seat, as that's how I've been cleaning them, followed by compressed air. I looked up schematics from Crowley's blow-up, but it shows the same inlet needles for the 1977 and the 1980 carbs that I have. They're actually different needles and presumably different seats.

I do not know about that.
You have to check the schematic for your engine.
Actually I never do anything to the inlet valve needle more than clean it with carb cleaner after I have had them in my Finsonic (same as Ultrasonic cleaner but another brand) cleaner.
Then I blow the carbs with compressed air.
Never have had an issue with leaking carbs due to bad seats or torne needle tips.

 

[racerone]

Your local machine shop can assist in removing those inserts.----And make new ones.

 

[Captndrydock]

Your local machine shop can assist in removing those inserts.----And make new ones.

Oh interesting, I'll look into that. Need to find a machine shop, but that does sound like a good option. Thanks!