Cracked Coolant Outlet Tube - ZR-1 Net Registry Forums

dzim · 05-07-2012

I am new to the ZR-1 Net Registry Forum and new to ZR-1's. I just purchased my 1994 ZR-1 in March so my "terminolgy" may not be perfect!

A little over a week ago, I noticed that my ZR-1 had an anti-freeze leak on the left front behind the power steering pump. With the help of my mechanic (and best friend), we did a cold pressure test and discovered the driver's side coolant outlet tube was the source of the leak. It seemed that the likely problem was the gasket between the outlet tube and the plenum. I ordered the gasket and a set of bolts from Jerry's Gaskets (who has been great to work with - thank you so much Jerry). When we removed the outlet pipe, we discovered the gasket was in perfect shape. However, the outlet pipe was cracked. I then ordered a new outlet pipe - again from Jerry's Gaskets and replaced the cracked outlet pipe, put on a new radiator cap, pressure tested the system, and refilled with anti-freeze. We actually re-used the original bolts and gasket as they were in great shape.

My ZR-1 has been in storage most of its life. The odometer currently reads 9,985 miles. I thank the previous owners for preserving it, but I plan to drive and enjoy it. After replacing the outlet pipe, I drove it 400 to a Corvette Show in Kansas City this past weekend. The car performed flawlessly and even received a Best of Class Award for 92 - 96 C4's.

In the last two months, all fluids in the ZR-1 have been replaced and the car has been completely detailed - inside, outside, and under the hood. I fully expected to have "some issues" with a car that has been in storage. If it would have blown a hose, it would not have shocked me. However, I did not expect to have a cracked outlet pipe.

As you know, the outlet pipe consists of a rectangular housing with an attached pipe that goes to a radiator hose at the front of the engine. The crack is not in the pipe. It is in the housing on the front shorter side of the rectangle. At this point, the housing would appear to be its strongest as the bolt holes are recessed from the front two corners. The crack is all the way through this portion of the housing and continues around the joint where the pipe is connected to the housing and finally ends on the back side of the housing.

I have no idea what would cause the housing to crack like this. If the bolts were over tightened, I would expect it to crack in the corners around the bolt holes. I also have no idea how the pipe is connected to the housing or what would cause that seam to crack.

I know "pictures are worth a thousand words" and I have sent pictures to a friend who has volunteered to help me by posting them.

I welcome your feedback and knowledge. If you have additional questions, I will do my best to answer them.

Thanks,
Dale Zimmerman
Lincoln, Nebraska
1994 Black Rose ZR-1 #113

Scrrem · 05-07-2012

Dale,
I have seen a few of these coolant tubes crack and it has alway been in the square part of the housing. This part of the tube is cast aluminum and it is more that likely just something as simple as.... what Marc H described as a very pourious casting. Over time of heating and cooling, it cracks in this same place. Maybe someone else can chime in here, but that's my best guess anyway....
Rich

VetteMed · 05-07-2012

yep, casting flaw would be my guess as to cause.

batchman · 05-08-2012

Welcome to the forum and to ZR-1'dom!

Glad to hear your first issue is containable even if it is somewhat odd. Thankfully with this community there is a lot of help for anything that does come up.

I hope to make it out to your neck of the 'woods' some day for the SCCA Solo Nationals at the Lincoln Airpark. Some day. Of course if I get there with the ZR-1 you'll get to see what they look like 'dirty'

.

Cheers,
- Jeff

oricale · 05-08-2012

That was exactly what I had on the passenger side as well
I cut a groove right into the crack and jb welded it and sanded it to perfection
And wala!fixed

GOLDCYLON · 05-08-2012

Not sure if this is the same side. There is however a single coolant outlet pipe on Ebay for $85

http://www.ebay.com/itm/Corvette-ZR1...b41280&vxp=mtr

Is your storage location heated? This almost looks like frozen fluid expansion stress breakage vs. boss stress? I noted you live in Nebraska which is known to get a little cold. My thoughts are heat cold heat cold heat cold stress will cause this to happen to any flaw.

VetteMed · 05-08-2012

Looks like the right part, has the bend for the AC lines clearance.

GOLDCYLON · 05-08-2012

Quote:

Originally Posted by VetteMed

Looks like the right part, has the bend for the AC lines clearance.

Yea my thoughts as well its the right part decent price for a single as well. What do you think about my theory?

VetteMed · 05-08-2012

Quote:

Originally Posted by GOLDCYLON

Yea my thoughts as well its the right part decent price for a single as well. What do you think about my theory?

I dunno, never experienced a freeze-up of an engine, the antifreeze would have to be in rather poor condition to allow freezing solid, especially at this time of the year?

GOLDCYLON · 05-08-2012

Quote:

Originally Posted by VetteMed

I dunno, never experienced a freeze-up of an engine, the antifreeze would have to be in rather poor condition to allow freezing solid, especially at this time of the year?

Concur however Florida and Arizona can't really comment on coldness lol.

05-07-2012	#2
Scrrem Join Date: Feb 2009 Location: Alexandria, Virginia Posts: 1,467	Re: Cracked Coolant Outlet Tube Dale, I have seen a few of these coolant tubes crack and it has alway been in the square part of the housing. This part of the tube is cast aluminum and it is more that likely just something as simple as.... what Marc H described as a very pourious casting. Over time of heating and cooling, it cracks in this same place. Maybe someone else can chime in here, but that's my best guess anyway.... Rich __________________ 1990 Bright Red Coupe #608 380 Stroker, Ported Heads/Intake/Housings/TB Haibeck Secondary Delete Chip / Pete's Cams George Braml Intake / FIC Injectors Coated SW Headers / Corsa Bill Boudreau B/B ZF6 / Viper 4.10 gears Ron Davis Radiator Pioneer AVIC-Z140BH NAV Fikse FM5's 285 / 335 / C6 Brakes WAZOO Member Last edited by Scrrem; 05-07-2012 at 04:06 PM.

05-07-2012	#3
VetteMed Join Date: Mar 2009 Location: Orlando, FL Posts: 1,828	Re: Cracked Coolant Outlet Tube yep, casting flaw would be my guess as to cause. __________________ 2004 Z06/Z16 LeMans Commemorative Edition 1991 ZR-1 #302 White/Gray (sold) 1991 ZR-1 #1147 Red/Saddle (sold)

05-08-2012	#4
batchman Join Date: Jun 2009 Location: I live at Devens, one run at a time Posts: 455	Re: Cracked Coolant Outlet Tube Welcome to the forum and to ZR-1'dom! Glad to hear your first issue is containable even if it is somewhat odd. Thankfully with this community there is a lot of help for anything that does come up. I hope to make it out to your neck of the 'woods' some day for the SCCA Solo Nationals at the Lincoln Airpark. Some day. Of course if I get there with the ZR-1 you'll get to see what they look like 'dirty' . Cheers, - Jeff __________________ [I]91 ZR-1 #1840, autocrossing in SCCA BSP. FIC S/S's DRM chip/Watson/Borla/lid/LW batt&headlights, springs, shocks, pads & lines, quick rack & Turn One, camber brace, 32/22mm sways, A/C halfway deleted 17x11 & 12 CCW's, 315 & 335 Hoosier A6s [/I]

05-08-2012	#5
oricale Join Date: Oct 2011 Location: STAFFORD VA, Posts: 576	Re: Cracked Coolant Outlet Tube That was exactly what I had on the passenger side as well I cut a groove right into the crack and jb welded it and sanded it to perfection And wala!fixed __________________ [B][I][COLOR=red]1990 ZR1[/COLOR][COLOR=black] [U]#00077 [COLOR=red]RED[/COLOR]/[COLOR=red]RED[/COLOR] (10Y022 PEP CAR) [/U][/COLOR][/I][/B][B][I][COLOR=red]1991 ZR1[/COLOR][COLOR=black] [U]#00517 ("Irene")[COLOR=red]WHITE[/COLOR]/[COLOR=red]RED-SOLD:cry:[/COLOR] [B][/B] [/U][/COLOR][/I][/B][B][I][COLOR=red]1992 ZR1[/COLOR][COLOR=black] [U]#00445("The Revenant")[COLOR=red][COLOR="Black"]BLACK [/COLOR][/COLOR]/[COLOR=red]RED(2016 T.O.D!) [/COLOR] [/U][/COLOR][/I][/B] [B][I][COLOR=red]2009 [COLOR=red]Z06!![COLOR=black]BLK/BLK rare Linen interior[/COLOR] 707HP!![/COLOR] [/COLOR][/I][/B] [B][I][COLOR=red]2006[/COLOR] BLK/BLK Z51 (Just SICK FAST!)SOLD)[/I][/B] [B][I]1996 BLK/BLK LT4 Grnsprt(sold...Twice!)[/I][/B] [B][I]1991 RED/REDL98(Fell off the shipping truck:([/I][/B] [B][I]1980 BLK/RED L82(Sold)[/I][/B] [B][I][B][I]1990[/I][/B] RED/BLK(sold.....In Japan)[/I][/B] [I][COLOR=black][B][I]2006[/I][/B][/COLOR][/I] [COLOR=red]Mustang GT[/COLOR] ([B][I]mach 1[/I][/B])[B](sold)[/B] [COLOR=black][B][I]1969[/I][/B][/COLOR] [COLOR=red]Mach[/COLOR] [B][I]1(sold in Japan)[/I][/B] [COLOR=black][B][I]1969[/I][/B][/COLOR] [COLOR=red]Mach[/COLOR] [B][I]1#2(sold)[/I][/B] [B][I]WAZOO Member...[/I][/B] [url]www.evolution-motorsport.com[/url] facebook/evolutionmotorsportengineering Your Local [url]www.Amsoil.com[/url] dealer/user.. Victory Loves Preparation

05-08-2012	#6
GOLDCYLON Join Date: May 2007 Location: Peoria, AZ Posts: 9,155	Re: Cracked Coolant Outlet Tube Not sure if this is the same side. There is however a single coolant outlet pipe on Ebay for $85 http://www.ebay.com/itm/Corvette-ZR1...b41280&vxp=mtr Is your storage location heated? This almost looks like frozen fluid expansion stress breakage vs. boss stress? I noted you live in Nebraska which is known to get a little cold. My thoughts are heat cold heat cold heat cold stress will cause this to happen to any flaw. __________________ GOLDCYLON - 91 ZR-1 #2014 GOLDCYLON - 90 ZR-1 #2794, 4L60e (Formerly Schrade's) GOLDCYLON - 11 CTS-V Arizona State Director 91 WHITE/BLACK #2014. 380 P&P&PCed,Ported Heads, Jeal Long tubes, Corsa Exhaust/FIKSE FM-5s /LED TLs, LED Headlights, Front Wilwood 6 piston narrowlite calipers and rear Wilwood caliper street shop mod,CNCed Coolant Pipes,TPI Cvr,Filter cover,Stainless Bolts, DRM/DOM PROM /ZFDOC mod build #102,DRLs,BMAD with stainless Debris Screen,Coplan Air Blaster, Pioneer APP Radio 4,Brey-Krause HB,Sub Bar,Fire extinguisher seat mount,DRM Coilovers,LEDs everywhere,Compass mirror (orange),V1 DIC hidden display, Homelink sun visor, Carbon Fiber top x3 and APSIS Carbon Fiber interior, APSIS CF Steering Wheel/NAPA Leather, Banski trailing arms, Guldstrand front suspension,urethane bushings from Prothane (total suspension) ZFDoc drive shaft safety loop, raptor shift light (orange),AO engineering louver front plate, Console seat cushion, 96CE seats with black custom Sheepskins, ss billet catch can,Viper remote entry/alarm,Cragar Rear Louvers,LED side louver lights, Dewitts Radiator with SPAL fans and a Woods 160 T-Stat 90 RED/BLACK #2794. 4L60e Automatic Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless Headers, Corsa Exhaust, SAN Secondaries and Haibeck PROM, Exotic Muscle Coil overs, LED Interior Lights, LED Tail Lights, LED Headlights, 94 Sport seats with black custom Sheepskins , Cragar rear louvers, GS Front calipers, Banski Trailing arms, APSIS Carbon Fiber steering wheel, Front and Rear Baer Eradispeeds, DRLs, Guldstrand front suspension,urethane bushings from Prothane (total suspension), Dewitt's Raditor with Dual SPAL fans and a Haibeck 170 T-Stat 11 RED/GREY CTS-V Last edited by GOLDCYLON; 05-08-2012 at 09:00 PM.

05-07-2012	#1
dzim Join Date: Apr 2012 Location: Lincoln, Nebraska Posts: 21	Cracked Coolant Outlet Tube I am new to the ZR-1 Net Registry Forum and new to ZR-1's. I just purchased my 1994 ZR-1 in March so my "terminolgy" may not be perfect! A little over a week ago, I noticed that my ZR-1 had an anti-freeze leak on the left front behind the power steering pump. With the help of my mechanic (and best friend), we did a cold pressure test and discovered the driver's side coolant outlet tube was the source of the leak. It seemed that the likely problem was the gasket between the outlet tube and the plenum. I ordered the gasket and a set of bolts from Jerry's Gaskets (who has been great to work with - thank you so much Jerry). When we removed the outlet pipe, we discovered the gasket was in perfect shape. However, the outlet pipe was cracked. I then ordered a new outlet pipe - again from Jerry's Gaskets and replaced the cracked outlet pipe, put on a new radiator cap, pressure tested the system, and refilled with anti-freeze. We actually re-used the original bolts and gasket as they were in great shape. My ZR-1 has been in storage most of its life. The odometer currently reads 9,985 miles. I thank the previous owners for preserving it, but I plan to drive and enjoy it. After replacing the outlet pipe, I drove it 400 to a Corvette Show in Kansas City this past weekend. The car performed flawlessly and even received a Best of Class Award for 92 - 96 C4's. In the last two months, all fluids in the ZR-1 have been replaced and the car has been completely detailed - inside, outside, and under the hood. I fully expected to have "some issues" with a car that has been in storage. If it would have blown a hose, it would not have shocked me. However, I did not expect to have a cracked outlet pipe. As you know, the outlet pipe consists of a rectangular housing with an attached pipe that goes to a radiator hose at the front of the engine. The crack is not in the pipe. It is in the housing on the front shorter side of the rectangle. At this point, the housing would appear to be its strongest as the bolt holes are recessed from the front two corners. The crack is all the way through this portion of the housing and continues around the joint where the pipe is connected to the housing and finally ends on the back side of the housing. I have no idea what would cause the housing to crack like this. If the bolts were over tightened, I would expect it to crack in the corners around the bolt holes. I also have no idea how the pipe is connected to the housing or what would cause that seam to crack. I know "pictures are worth a thousand words" and I have sent pictures to a friend who has volunteered to help me by posting them. I welcome your feedback and knowledge. If you have additional questions, I will do my best to answer them. Thanks, Dale Zimmerman Lincoln, Nebraska 1994 Black Rose ZR-1 #113 Last edited by QB93Z; 05-07-2012 at 04:30 PM. Reason: add pictures

05-08-2012	#7
VetteMed Join Date: Mar 2009 Location: Orlando, FL Posts: 1,828	Re: Cracked Coolant Outlet Tube Looks like the right part, has the bend for the AC lines clearance. __________________ 2004 Z06/Z16 LeMans Commemorative Edition 1991 ZR-1 #302 White/Gray (sold) 1991 ZR-1 #1147 Red/Saddle (sold)