Throttle body vacuum leaks


#1

There are 3 pipes that go into your throttle body and you should use some JB Weld to permanently epoxy them into place. If you’re standing by the LF tire, there’s 2 AL pipes that go into the throttle body from the R and one on the L. The ones on the R go to the over complicated brake vac system. The one on the L goes to the Idle Air Control Valve (IACV). They’re supposed to be a press fit but in our old cars they get sloppy loose and become vac leaks.

How to fix. Pull the AL pipes out of their ports, clean the mating surfaces with brake cleaner and a little scrubbing, then fasten them back up with JBWeld or some kind of epoxy.

I fooled with 4 other people’s cars this weekend as I modded them to take the MAF so we could do more testing. Everyone of those cars had 3x loose pipes going into the throttle body. One of them, we expoxied up at the track.

How to simplify the over-complicated brake booster vac lines. Simplifying vacuum lines


#2

Tag…

Btw, amazing research


#3

I can’t tell if you’re kidding or not. Wasn’t any research here. Was just a matter of having a 30yr old car and all my shit was always screwed up. So I got to thinking, time and time again, how can I make this less of a cock-up?..you know as in like “how can I make this problem reliably go away?” 11yrs now of “how can I make this less of a cock-up” makes for lots of little solutions.

Of course, an equal # of my ideas don’t pan out.

Alternately, I steal terrific ideas from other people, try them out, and if they work well I try to get the word out so others can avoid some of the goatscrews that have kicked my ass over the years.


#4

Analysis isn’t always on the issues we think are worthy. But it is good, so accept it damn you.


#5

Lol, ok. Thanks for the kind words. Beer’s on you.


#6

Adding to Scott’s post as I should have looked here before Facebook

The final frontier of throttle body leaks are the two needle bearings that the shaft which opens/closes the throttle body/controls the throttle switch. From what I can tell, the original bearings are out of production. However, there is an updated design that actually has two seals as opposed to one.
Manufacturer: INA
Part number: HK0812-2RS
Google search should bring them up, I found them on Amazon and eBay. Was around $20 for two of them.

To replace them:
Unscrew the two screws for the butterfly flap and remove the flap. Careful with this as the screws like to strip, use a well fitting driver

Pop the little circlip out of the bottom/above where the throttle switch connects to the shaft. This can be a bit of a pain, but small pliers on Amazon go along way

On top of the throttle body’s two coiled springs take off the bolt on the spring that is away from the main butterfly shaft. Believe it’s an 11mm if I recall correctly
Now is a good time to take pictures of how the spring/shaft assemblies fit together.
Carefully pull the entire spring assembly up, the butterfly shaft should come along. Be a little careful as the springs are under tension. They are turned twice, which you’ll need to remember for reassembly
I believe there is a washer or spacer or two along the way that I have missed in my description. Obviously take note of those
Now you should have the top and bottom bearings exposed. I used a typical 2 jaw blind bearing puller with an 8mm fitting and they came right out, I have heard of people using slide hammers and having issues and needing to resort to dremels. Obviously want to do anything you can to preserve the barrel fitting in the body of the throttle body.
Once you’ve got them out, press the new ones in keeping the writing on the bearing facing outwards. If you marred the barrel surface in the housing, use permatex #2 or aviation flange sealant to address it as you press the new bearings in. Easier to do if you have a press, I used a hammer and wood to press them in.

Reassemble in reverse order of taking it apart. I put a little grease on the butterfly shaft when putting it in, but the bearings already had some. Do be careful when threading that through the new bearings to avoid tearing the new seals you just installed.
Again, those springs get two winds to have proper tension, a hook/pick is a useful tool to help

All in, takes about 45m to an hour. I know I missed mentioning a washer or two, so just pay attention there!