Throttle body dilemma

[SteveJ8672]

Hi Folks, well the strip down and cleaning was going so well until I started on the third throttle body which has the STVA on the bottom, the bottom butterfly valve is fine and free but the top primary is really stiff almost feel seized, surely that is not normal and I doubt an easy fix.

[Hooli]

Hmm, have fun with that. I've never stripped a TB far enough to get to the bushes they run in. I'd try some ACF-50 or something & ignore it for a few days to see if it penetrates & frees the spindle from the bush.

[SteveJ8672]

Hmm, have fun with that. I've never stripped a TB far enough to get to the bushes they run in. I'd try some ACF-50 or something & ignore it for a few days to see if it penetrates & frees the spindle from the bush.

I've got the offending assembly soaking in a pot of plusgas, I'll check on it in a couple of days, if not do the same with acf50 and cross me fingers.

[T250]

I've got a complete throttle body with sensors, fuel rail, end covers, stv, vac hoses and connectors if you get stuck, can't remember how much I paid but could look back if your interested?

[SteveJ8672]

I've got a complete throttle body with sensors, fuel rail, end covers, stv, vac hoses and connectors if you get stuck, can't remember how much I paid but could look back if your interested?

Cheers for the offer mate, I'll keep you posted.

[Snapey]

Steve it's an easy fix. The STVA has two magnets and one of them has let go. Just re-glue it with a 24 hour epoxy. I've got photo's I'll post when I find the bloody things.

[Snapey]

Just reading back through the posts & I'm a bit confused. Is your problem in a throttle body or the STV actuator. If the actuator here are some photo's. If the TB then I can't help. Good luck.

Things have changed here since I used to post photo's & it looks like I need a host site. Let me know if you need photo's Steve & I'll see if I can work out this photo thing.

[KiwiCol]

Gidday Snapey, been ages since we've seen ya here!   Great you called in mate!

[Hooli]

Just reading back through the posts & I'm a bit confused. Is your problem in a throttle body or the STV actuator. If the actuator here are some photo's. If the TB then I can't help. Good luck.

Things have changed here since I used to post photo's & it looks like I need a host site. Let me know if you need photo's Steve & I'll see if I can work out this photo thing.

Ayup.

You don't need a hosting site but it's still a bit of a faff. Col did a guide ages ago https://gsx1400owners.org/forum/index.php?topic=7530.0

[SteveJ8672]

Just reading back through the posts & I'm a bit confused. Is your problem in a throttle body or the STV actuator. If the actuator here are some photo's. If the TB then I can't help. Good luck.

Things have changed here since I used to post photo's & it looks like I need a host site. Let me know if you need photo's Steve & I'll see if I can work out this photo thing.

Hiya mate, it is the 3rd throttle body which houses the STVA on the bottom butterfly valve, but that is fine and moving freely it's the top butterfly valve which I assumed is the primary that I'm having the issue with. Is that also linked to the STVA?

[Snapey]

it's the top butterfly valve which I assumed is the primary that I'm having the issue with. Is that also linked to the STVA?

It's years since I've worked on the TB's so things are a bit vague but I doubt they're linked. The STVA only operates the chokes. I presume you have the TB's separated so is it only number 3 that's stiff? Bent shaft maybe? Unscrew the butterfly & remove the shaft is about all I can suggest.

[Eric GSX1400K3]

I recall the primary butterflies move in one direction, the secondaries in the other.  The manual (section 4-54 to 4-65) go into great detail on these TB's which I'm sure you've already seen.

[Hooli]

Just reading back through the posts & I'm a bit confused. Is your problem in a throttle body or the STV actuator. If the actuator here are some photo's. If the TB then I can't help. Good luck.

Things have changed here since I used to post photo's & it looks like I need a host site. Let me know if you need photo's Steve & I'll see if I can work out this photo thing.

Hiya mate, it is the 3rd throttle body which houses the STVA on the bottom butterfly valve, but that is fine and moving freely it's the top butterfly valve which I assumed is the primary that I'm having the issue with. Is that also linked to the STVA?

It's not linked to the STVA once the TBs are taken apart. If you've not noticed the fast idle adjustment above the STVA is linked to the primary butterflies, the STVA turns backwards to push them open slightly for the fast idle when cold. Try not to adjust that screw & the Y shaped bit it sits in as the setup procedure is a bugger to get it all right again. I know as I had to do it once because mine had got seized & caused various issues.

I'd have thought the bushes for the butterfly spindles were white metal or brass, I'd be amazed if it wasn't a solid type of bearing. So should just be down to corrosion/dirt making it sticky.

[SteveJ8672]

Just reading back through the posts & I'm a bit confused. Is your problem in a throttle body or the STV actuator. If the actuator here are some photo's. If the TB then I can't help. Good luck.

Things have changed here since I used to post photo's & it looks like I need a host site. Let me know if you need photo's Steve & I'll see if I can work out this photo thing.

Hiya mate, it is the 3rd throttle body which houses the STVA on the bottom butterfly valve, but that is fine and moving freely it's the top butterfly valve which I assumed is the primary that I'm having the issue with. Is that also linked to the STVA?

It's not linked to the STVA once the TBs are taken apart. If you've not noticed the fast idle adjustment above the STVA is linked to the primary butterflies, the STVA turns backwards to push them open slightly for the fast idle when cold. Try not to adjust that screw & the Y shaped bit it sits in as the setup procedure is a bugger to get it all right again. I know as I had to do it once because mine had got seized & caused various issues.

I'd have thought the bushes for the butterfly spindles were white metal or brass, I'd be amazed if it wasn't a solid type of bearing. So should just be down to corrosion/dirt making it sticky.

No worries Hooli, thanks. I've not touched any screws or adjusters & do not intend to, hopefully no adjustment will be required when I slot the tb's back together. Fyi day 4 it is slowly freeing up to almost a slight resistance yea!!, 2 days soaking in Plusgas then 2days in Acf50.

[Hooli]

One thing you can check, the 'Y-shaped' adjuster with the fast idle screw in can stick on it's pivot. I had that years ago. Not only causes random idle speeds but will cause C28 (STVA) errors & the FI light on.

Because there's no feedback from the STVA the only way the ECU knows it's working is to monitor both the TPS & SPS to see the expected adjustments when it signals the STVA. So things out of adjustment there can cause it to think there's a STVA fault.