high pressure throttle body shaft seal?
08-02-2013, 10:37 AM
#1
Launching!
Thread Starter
Join Date: Jul 2011
Location: Detroit, Michigan
Posts: 209
Likes: 0
Received 0 Likes
on
0 Posts
high pressure throttle body shaft seal? Does anyone know where to find some kind of high pressure throttle shaft seal for the stock Ls1 throttle body? Found out my seal is blowing tons of air out of it. I cant even find a replacement seal for it. Would another car have a seal that would fit?
08-02-2013, 12:01 PM
#3
Launching!
Thread Starter
Join Date: Jul 2011
Location: Detroit, Michigan
Posts: 209
Likes: 0
Received 0 Likes
on
0 Posts
it is letting out a ton of air. I have been trying to find something online, but cant seem to find anything that will work.
someone has to have had this same issue with boost
someone has to have had this same issue with boost
Trending Topics
08-05-2013, 09:02 AM
#8
Launching!
Thread Starter
Join Date: Jul 2011
Location: Detroit, Michigan
Posts: 209
Likes: 0
Received 0 Likes
on
0 Posts
I think a "ton of air" is a mammoth exaggeration unless your TB shaft etc is so fucked it would be deemed scrap in the first place.
U could try flipping the old seal around
why not a new tb?
Haven't had 1 apart, but could there be space to put 2 seals in, back to back??
08-05-2013, 10:44 AM
#9
Get a used stock one off of ebay for $50-$100, throw it on there and see how it does.
I try not to monkey around with throttle bodies too much, that blade can get set up wrong once and then you get a stuck throttle situation... not worth the risk in my opinion....would be a bummer if it got stuck while driving and you wreck the car, kill someone or blow the motor.
And to be honest, guys are going 8's on stock truck intakes and truck throttle bodies...no need to spend $300+ on an aftermarket throttle body unless your money tree is dropping hundos...
I try not to monkey around with throttle bodies too much, that blade can get set up wrong once and then you get a stuck throttle situation... not worth the risk in my opinion....would be a bummer if it got stuck while driving and you wreck the car, kill someone or blow the motor.
And to be honest, guys are going 8's on stock truck intakes and truck throttle bodies...no need to spend $300+ on an aftermarket throttle body unless your money tree is dropping hundos...
08-06-2013, 10:17 AM
#10
Launching!
Thread Starter
Join Date: Jul 2011
Location: Detroit, Michigan
Posts: 209
Likes: 0
Received 0 Likes
on
0 Posts
Get a used stock one off of ebay for $50-$100, throw it on there and see how it does.
I try not to monkey around with throttle bodies too much, that blade can get set up wrong once and then you get a stuck throttle situation... not worth the risk in my opinion....would be a bummer if it got stuck while driving and you wreck the car, kill someone or blow the motor.
And to be honest, guys are going 8's on stock truck intakes and truck throttle bodies...no need to spend $300+ on an aftermarket throttle body unless your money tree is dropping hundos...
I try not to monkey around with throttle bodies too much, that blade can get set up wrong once and then you get a stuck throttle situation... not worth the risk in my opinion....would be a bummer if it got stuck while driving and you wreck the car, kill someone or blow the motor.
And to be honest, guys are going 8's on stock truck intakes and truck throttle bodies...no need to spend $300+ on an aftermarket throttle body unless your money tree is dropping hundos...
As much as I wish I did, there is no money tree here. thus the reason behind trying to seal my throttle body and not spending money on other throttle bodys. purchasing another stock unit when mine was perfectly fine doesnt make sense to me. I can see the truck units and drive by wire units holding much better because the shaft and entire unit is completly sealed. This is not the case with a drive by cable TB.
There is no way to setup the blade wrong, it goes in only one way and bolts in only one way. The only way it might become a problem is to do something to the seal that would cause so much friction it would make it sticky. The spring is for snap back, so it would have to be pretty sticky to not close. Besides in a stuck throttle situation the clutch goes in, the gear gets disingaged and car powered off. No need to go killing people around here.
I have had this thing apart 3 times now, and working on perhaps my final attempt of sealing it. I will find out tonight if it worked.
08-06-2013, 03:46 PM
#12
Funny. I have a 78mm Accufab on my NA car. I chased a high idle FOREVER. First intermittent, that it got worse. After having most the car apart and swapping parts, I finally narrowed it down to the throttle shaft seal on the Accufab. Went back to stock and no more problems...
I smoke tested the car twice and never got any smoke from that area. Just a lot of tail chasing. I can't believe this issue is more prevalent, especially like you mentioned on an FI setup.
I smoke tested the car twice and never got any smoke from that area. Just a lot of tail chasing. I can't believe this issue is more prevalent, especially like you mentioned on an FI setup.
08-07-2013, 08:10 AM
#13
Launching!
Thread Starter
Join Date: Jul 2011
Location: Detroit, Michigan
Posts: 209
Likes: 0
Received 0 Likes
on
0 Posts
The results are in... I was able to seal it up. My final rendition of the shaft seal worked perfectly. High pressure no leaks. Best of all it cost me nothing. That was the goal!
--Success--
--Success--
08-07-2013, 12:48 PM
#15
Launching!
Thread Starter
Join Date: Jul 2011
Location: Detroit, Michigan
Posts: 209
Likes: 0
Received 0 Likes
on
0 Posts
Here it is...
I found out while doing multiple on and offs with my throttle body, stock unit using the edelbrock pro-flo it was barely covering the intake opening by maybe 1mm if that. Using the stock intake this would not be a problem, but somehting to keep in mind when using larger intakes. A plate was made to make up the difference on the intake manifold, but as far as the seal here it is.
I took the throttle body apart, and removed the rubber seal that the throttle shaft slides into. The way the seal is made makes sense for a naturally aspirated engine because it keeps the seal tight under vacume. unfortunatly under positive pressure the seal just lets air out because its not strong enough.
Here is a model I did to show the seal. I didnt take a picture of the factory seal so this will be a good representaion.
You can see how the sealing portion of rubber is bubbled outboard.
When on the shaft and under pressure this flap type rubber seal just spreads and lets air out
By flipping the seal it acts in a reverse idea. Under pressure the seal flap becomes pressed outboard and in tern making the seal tighter.
In addition to flipping the seal I added an O-ring that fit inside this flair type of indention to strengthen it.
I then added another smaller O-ring on top of that one that added another place of sealing.
I also added the same size O-ring on the opposite side creating 3 points of contact aiding in the sealing.
I then put the seal back in the throttle body reverse of the factory position and sealed it in with rtv silicone. The seal doesnt exactly fit tight reversed so the silicone is important to seal the outsides.
I let it dry over night before I reasembled the throttle body
I found out while doing multiple on and offs with my throttle body, stock unit using the edelbrock pro-flo it was barely covering the intake opening by maybe 1mm if that. Using the stock intake this would not be a problem, but somehting to keep in mind when using larger intakes. A plate was made to make up the difference on the intake manifold, but as far as the seal here it is.
I took the throttle body apart, and removed the rubber seal that the throttle shaft slides into. The way the seal is made makes sense for a naturally aspirated engine because it keeps the seal tight under vacume. unfortunatly under positive pressure the seal just lets air out because its not strong enough.
Here is a model I did to show the seal. I didnt take a picture of the factory seal so this will be a good representaion.
You can see how the sealing portion of rubber is bubbled outboard.
When on the shaft and under pressure this flap type rubber seal just spreads and lets air out
By flipping the seal it acts in a reverse idea. Under pressure the seal flap becomes pressed outboard and in tern making the seal tighter.
In addition to flipping the seal I added an O-ring that fit inside this flair type of indention to strengthen it.
I then added another smaller O-ring on top of that one that added another place of sealing.
I also added the same size O-ring on the opposite side creating 3 points of contact aiding in the sealing.
I then put the seal back in the throttle body reverse of the factory position and sealed it in with rtv silicone. The seal doesnt exactly fit tight reversed so the silicone is important to seal the outsides.
I let it dry over night before I reasembled the throttle body
Last edited by User-c3; 08-07-2013 at 12:54 PM.
