Cooling Port for 1990 Lt5

[ZuggZR1]

This cooling connection came off my 1990 ZR1. How does it connect so I can make sure it dont come off again. Im very new to corvette ownership so please dont be to cruel LOL

[efnfast]

It's a press fit.
Where did you get that siamesed plenum?

[Paul Workman]

Steve is right; orignially a press-fit.

Couple options:

A machine shop may be able to fix it

You could pull the plenum and drill/tap the coolant port with a 3/8" plug in the Injector housing, and (for show) JB Weld the connector to the plenum. (unless you drive in SUB ZERO (Fº) temps you'll NEVER need to heat the TB. AND, the plenum will run considerably cooler which benefits the ignition module that is attached under the plenum).


Welcome to the BROTHERHOOD OF THE BEAST! (And, who's ZR-1 was that??)

[ZuggZR1]

was my good friend ( like a brother) Tony Zulkowsi from De

[ZuggZR1]

Yeah I live in NC no major sub zero here. So for the time being your saying JB weld till I can get to a machine shop? Look slike it has a grey putty like sustance on it now possible JB weld

[ZuggZR1]

here is full view of the engine.

This is a DRM 500 ZR1

[billschroeder5842]

Thank is a great looking engine

[Ccmano]

Does coolant come out when you start the engine?
H
:cheers:

[TX '90 ZR1]

Yeah I live in NC no major sub zero here. So for the time being your saying JB weld till I can get to a machine shop? Look slike it has a grey putty like sustance on it now possible JB weld

I don't think Paul is recommending you JB Weld the fitting and use it. Think he is referring to blocking the coolant flow from the plenum with the plug (there are posts here on the forum detailing the procedure) and using the JB Weld to hold the fitting in place to give it a stock look.
:cheers:

[ZuggZR1]

It did but plugged it back it and is staying but rather fix it right so not an issue

[Ccmano]

As stated it was a press fit to begin with. I would use a sealant like clear RTV and put it back on.
H
:cheers:

[ZuggZR1]

excuse my newbieism i can get the rtv at autoparts store?

[ZuggZR1]

Which one is better:

1: https://shop.advanceautoparts.com/p/permatex-water-pump-and-thermostat-rtv-silicone-gasket-5-oz-22071/7160009-P?searchTerm=Permatex

2: https://shop.advanceautoparts.com/p/permatex-high-temp-red-rtv-silicone-gasket-3-oz-81160/7160114-P?searchTerm=Permatex

I wann aget this fixed today if possible.

thanks again for all your help guys

[Ccmano]

Either will work, I would use the RTV.
H
:cheers:

[Paul Workman]

I don't think Paul is recommending you JB Weld the fitting and use it. Think he is referring to blocking the coolant flow from the plenum with the plug (there are posts here on the forum detailing the procedure) and using the JB Weld to hold the fitting in place to give it a stock look.
:cheers:

Yes. You understood what I was trying to say. :cheers:

[Z51JEFF]

You won’t have to worry about any wise a$$ comments from this group,everybody gets along here and is more than glad to assist. As stated I’d bypass the TB and just plug the elbow back in and run some dummy hoses to the elbow to make it look like it’s stock,more or less. As far as trying to get it to stay in and use it for the intended purpose I’d think once it comes out there’s nothing that can be done to keep it in place,once it’s compromised,pulled out it’s done. If the plenum is powder coated maybe it was removed during the process.

[ZuggZR1]

Ended up using JB weld and placed back in after sanding the connector and cleaning up. let it cure 24 hours. Will test tonite when I jack up right side of car and add remaining coolant

[ram_g]

Zugg, did this fix hold? Or did you need to do something else to permanently solve the problem?

Also, when the fitting came out, were you driving and was there an immediate sign of a problem such that you pulled over and stopped?

I will shortly start a new thread but I have a similar (not identical) issue.

[Corvette95]

Holley make a direct replacement, I have it on mine. You tap the port and screw in the exact press in fitting with the same upward twist...direct fit. It is one of these...sorry can't remember which. 782205ERL Earl's Vapor Guard? Hose End
782252ERL Earl's Vapor Guard? Hose End
782256ERL Earl's Vapor Guard? Hose End

[ZuggZR1]

JB weld held and yes it happened while driving the Engine started to over heat

[ram_g]

Corvette95, thank you for this suggestion. Of the 3 part numbers listed, it would have to be #782252 as that is the one with the 1/8 NPT threaded connection; the others would be too big.

I was going to start another thread but I may as well add on to this one as I am not really thread-jacking, just resurrecting an old one.

At some point in the past, my driver side plenum coolant air bleed L fitting was replaced with a T with one side capped off, see first pic. I've noticed a slow accumulation of coolant in the valley below that I had attributed to a leaky plenum gasket, but yesterday I noticed that the leak is probably from around the fitting, see second pic. It's possible that there might have been an issue like this in the past, which is why they might have messed with the fitting to start with.

I can either
(a) ignore it - which would be fine as long as I am comfortable that it won't blow off while driving and catastrophically dump coolant. The leak/weep is so small that I don't think that this is imminent.
(b) fix the fitting as per suggestion above to replace with drilled and tapped NPT fitting,
(c) block throttle body coolant flow and avoid the issue altogether.

Any opinions from the experts?

https://www.zr1.net/forum/picture.php?albumid=477&pictureid=4497

https://www.zr1.net/forum/picture.php?albumid=477&pictureid=4499

[ram_g]

JB weld held and yes it happened while driving the Engine started to over heat

Just saw your response, thanks! Wonder if this is a common issue? I've been searching for this sort of thing and yours is the only example I could find...see my post above for why I am concerned. Thanks again.

[We Gone]

Had the same thing happen on a 93, I also cleaned everything well and did the JB Weld 4 years ago still holding just fine.