Difugledy with TB pipe

[padgett]

Ordered a couple of the dual Oring p/n 25533986 throttle body coolant pipes from GM. Verified it is intended for the LN3 © 3800 according to the GM computer.

Minor issue and one I was concerned about when I saw one in the earlier post was that the end seemed longish.

Now that I have one in hand, I can say "it is too long".

In the one photo you can see the difference in length. In the other that when it is bottomed in the TB, the Oring does not even touch the TB housing.

Obviously I need to shorten it a bit. No big but loks like if in the IM and inserted inthe TB, then the two bolts are tightened, nasty things might happen.

Has anyone actually installed one in a car and what did you need to do first ?

[Guest crazytrain2]

Can you cut a small section of the pipe out, rough both ends up a little w/sand paper and replace cut out section with 1/2" ID hose and a couple of hose clamps?

[padgett]

Since the longer straight section is only 2" from curve to O-ring, that would be difficult. An thinking would be better to remove 1/4" from end, is about 5/8" from end to O'ring now.

[padgett]

No-one has actually installed one of these ? Going to fire up the cut-off tool this morning.

[padgett]

Cut off the new pipe to match the old one better and verified it now goes into the TB. (Yes Virginia, I removed the Orings while shortening).

Everthing together, replaced some wire covers, now has proper shields on crossover pipe (why someone would remove I have not a clue).

BTW is much easier to work on TB with exhaust crossover removed but very difficult to reinstall unless you start the rearmost bolt closest to the engine first and then I needed to remove the IAC (needed cleaning anyway) first to get my hand in there..

Note: a small round TV dinner plate with one side cut out makes an excellent catchpan in case you drop one of the non-magnetic IAC screws.

Everything seems to be well sealed & no leaks visible now when revved & fully warmed up. Just need to test drive after I do a couple more minor things.

[Guest crazytrain2]

Padgett,

Was waiting to go to school on you before replacing mine

Any advice / tips you care to share with the class? Did you have to pull fuel rails/lines, thermostat or anything on the IM side (around and or above the stubby end of the new coolant pipe)?

Did you use any hi-temp silicone or JB Weld? I don't want to take this apart more than once (I'll be lucky if I can accomplish taking it apart once)

Thanks for the help!

[padgett]

By choice I do not use any sealers or liquid gasket unless there is a gap. Surfaces were all cleaned/shiny/straight and I did lubricate the gaskets and O-rings with a light oil before installing. This includes the gasket for where the curved pipe mounts onto the manifold.

Only thing removed was the throttle body: plenium, fuel rail, & EGR all stayed in place. Did R&R the exhaust crossover which made cleaning the manifold surfaces & seeing the manifold connections easier but was because PO had removed the heat shields so was replacing with one that had (are riveted on).

Did need to tap on curved pipe to seat far enough to start nuts.

Idled for about 10 minutes and drove for 5 miles & seems dry.

[Guest oceandaemon]

padgett I don't suppose you happen to still have or know where to get one of the what appears to be re designed L coolant pipe that uses an O-ring on both ends?

 

My car developed the issue just the other day where a leak formed where the L pipe goes into the throttle body. Taking it apart revealed that while my car's L pipe has an O-ring on the side going into the manifold, it does not have one on the end going into the throttle body. I tried putting it back together with some RTV but it leaked even worse than before.

 

The part number you originally listed for the pipe seems to be no longer in production by GM. 

Edited May 12, 2017 by oceandaemon (see edit history)

[DAVES89]

I think I have one from one of the two engines I just junked. If interested email me at; lemke1044@aol.com

 Just checked and I don't. Sorry.

Edited May 12, 2017 by DAVES89 (see edit history)

[89RedDarkGrey]

On ‎9‎/‎3‎/‎2011 at 10:32 AM, padgett said:

No-one has actually installed one of these ?

 

5 YEARS later- I can post that yes, I did. I didn't know of this Forum at the time, when I first bought my basket case.

 

 

Actually- I did not "install" mine- the FelPro IM gasket set came with all O-rings (injector, TB, etc.) and I just cleaned the tubes, greased their O-rings, and assembled. The one smaller tube uses a gasket, with 2 bolts. I always use Permatex Gasket Dressing on dry paper gaskets.

 

[DAVES89]

I have the tube in 89RDG's picture. The one in the left picture dated 07/27/2012

[2seater]

I may have the "L" shaped one in a parts box or spare manifold. I do not use them on my summer only car so I tap the holes for pipe plugs. I will look.

[Guest oceandaemon]

I am going to take it back apart this afternoon and see if I can figure out what is going on with it. This is my first time doing the gaskets on a LN3 (have done many Series II intakes before though), and this car has actually had the intake gaskets done before by someone using the same felpro kit I used, so I am unsure if they simply left out the O-ring to the L pipe going into the TB or if it did not have one originally. Hopefully my investigating this afternoon will turn up some results. 

 

 

I will also see if I can get some decent pictures of the pipes from mine when I have them out.