Air leak between UICP and Throttle body.

[Eclipsed]

I have searched for quite a while and nothing exact comes up as a solution. So far the only two possiblities I have come up with are:

1. A bad seal between the throttle body and the ic pipe. ( I have a dejon tool pipe if that matters.)

2. The shaft seals are worn out in the throttle body itself.

I just replaced the gasket between the ic pipe and the throttle body and it still leaks. And I don't think it is the shaft seals because there is no play at all on the shaft itself. It is as solid as a new throttle body. And the leak does seem to be coming from between the ic pipe and the throttle body. As if the gasket isn't sealing correctly.

My questions are, should I just go ahead and replace the o rings inside the throttle body? Or should I try some sort of gasket sealant on the gasket itself? That is the reason why I posted. Because I can't find a thread suggesting to use gasket sealant or to replace the o rings inside the throttle body if the shaft has no play what-so-ever. I would hate to go trough all the work of replaceing the seals to find out that wasn't the problem. And the leak doesn't seem to be coming from the shaft itself, just between the pipe and the throttle body.

I do have the gaskets themselves and haev checked these two sites on how to do it.
http://www.ca.dsm.org/faq/tb-shaftseals.html
http://www.plymouthlaser.com/tbor.htm

I would just rather avoid the headache if it isn't the problem. Thanks for any help.

edit: During the leak test I can't boost any higher than 6 psi and because it leaks so bad.

 

[Stapl3]

Since when did leaky TBs have shaft play?

Did you spray soapy water on the leaking area to see where it bubbles?

 

[Eclipsed]

Since when did leaky TBs have shaft play?

Did you spray soapy water on the leaking area to see where it bubbles?

The majority of what I have found point to a loose shaft as bad seals.

I will try soapy water asap. If you put your hand over it is obviously coming from between the pipe and the throttle body. I will still try soapy water tomorrow though.

Are there any problems from using gasket sealant with this particular gasket?

 

[Kevin Jewer]

Dejon tool still using those weak 1/8th flanges? I would be amazed if those things don't leak. It's also very common for TB elbows and UICPs to have a warped TB flange (from welding). I take all pieces to my machinist to get planed flat before I waste my time installing them.

 

[donmagicjuan]

That is exactly what I had to with my Dejon UICP. I really wish they would machine them flat after the welding, but to make matters worse they throw a nice powdercoating on there for good measure. If you still have problems with it sealing after having it machined, you can use some silicone RTV gasket between the UICP and the throttle body. Just keep in mind that it will be a giant pain every time you have to remove the pipe. I would only use that as a last resort.

 

[Eclipsed]

Ok, will do. If machining doesn't work, and I use the sealant, is there a special kind I should use or a kind I should stay away from?

I will definitally get it machined asap.

 

[Kevin Jewer]

I also used a thick cork type gasket with some success. It will flatten out over time though, and cutting out a new one every so often was a pain in the ass.

If this pipe has the super thin dejon flange there may not be much to plane off, and it may not stay flat for long. I would still try it, just keep an eye on it. I love Dejon's pipes, I just try to avoid anything with a flange on it.

 

[Eclipsed]

I also used a thick cork type gasket with some success. It will flatten out over time though, and cutting out a new one every so often was a pain in the ass.

If this pipe has the super thin dejon flange there may not be much to plane off, and it may not stay flat for long. I would still try it, just keep an eye on it. I love Dejon's pipes, I just try to avoid anything with a flange on it.

I took it into a shop today and the guy said it was too thin to plane flat. He said he would try, but it wouldn't help that much. He flatened all of the coating off, but didn't do too much more because it might cut too thin and risk the integrity of the flange.

I will probably just try some sealant as well. Should I still use a gasket with sealant? Or just use the rtv stuff between the pipe and the throttle body?

 

[DSMunknown]

I will probably just try some sealant as well. Should I still use a gasket with sealant? Or just use the rtv stuff between the pipe and the throttle body?

If you can find a matching gasket or fabricate one, then you should do that. I would recommend using a gasket in combination with RTV silicone sealant. If you decide to do this, lube up both sides of the gasket. As it says on the directions, you should wait a full 24 hours to let the silicone to fully cure.


This one should be fine to use (or anything similar):
http://www.cbperformance.com/catalog.asp?ProductID=1069

You can find this and other similar types of RTV silicone at most NAPA stores.

 

[Eclipsed]

If you can find a matching gasket or fabricate one, then you should do that. I would recommend using a gasket in combination with RTV silicone sealant. If you decide to do this, lube up both sides of the gasket. As it says on the directions, you should wait a full 24 hours to let the silicone to fully cure.


This one should be fine to use (or anything similar):
http://www.cbperformance.com/catalog.asp?ProductID=1069

You can find this and other similar types of RTV silicone at most NAPA stores.

Thanks. I actually have a tube of that exact stuff in my garage so it works out. I hope it seals.

Thanks again to everyone who helped.