leaky radiator hose diagnosis please

[billschroeder5842]

Today I discovered I have a coolant leak on the passenger side.

The leak seems to be coming from the lower radiator hose (the one with the mesh) but I can't tell for sure as it is pretty much spaghetti down there. I'm not getting drips on the concrete but clearly getting splotches, seepage and spray on the passenger side of the engine hoses.

The coolant is on the horizontal frame under the lower hose and the oil cooler hoses are wet on the underside. The spray will go as far as the "A" arm bushings but not past the center of the engine.

I cleaned it up a few times so I could put an eyeball on it to locate the leak. I can not seem to re create the leak at idle or low rpms. Now, if I take her out and get on it a bit, I pop the hood and I have coolant all over the general area.

My question... is there a "typical" place in that lower radiator hose area that leaks that I need to be checking?

I had a bit of coolant on the radiator, but I can't tell if that is the cause of the leak or just the over spray.

I'm typically not one to throw parts at a situation but I ordered a full set of hoses from Jerry's as PM and hopefully to solve my issue. The hoses are original so they need to be replaced anyway.

Anything else that need to check?

[DRM500RUBYZR-1]

Bill,
Although I would simply replace the lower hose ( because you have them)and go from there, here is the proper way.

Mityvac MV4560 Radiator/Cooling System and Pressure Test Kit



s/b $50.00 or less

:cheers:
Marty (https://www.amazon.com/Mityvac-MV4560-Radiator-Cooling-Pressure/dp/B003V9L05G/ref=sr_1_1?s=automotive&ie=UTF8&qid=1485650544&sr=1-1&keywords=radiator+pressure+tester#Ask)

[Dynomite]

Check the Heater Coolant Return fitting at the Thermostat Housing

Heater Return Fitting (http://www.jerrysgaskets.com/nipple-heater-coolant-return-90-95-7c4/)

Rather than just idle and low rpm.......rev it up and check from above as someone revs it up a bit.
The Radiator Drain Plug might also be a place but in general it could be any one of the lower radiator hose ends from water pump to thermostat housing or between thermostat housing and radiator. Or as Ted suggests....the Water Pump.

Speaking of the Radiator Drain Plug.....my worst leak ever was a coolant leak from a new Ron Davis Radiator I mistakenly installed the provided Aluminum Allen Head Drain Plug (with Permatex). NEVER Install an Aluminum Plug in a Aluminum Radiator......it would not stop leaking and had a time trying to remove it as it galled the threads. After re-threading and installing a Brass Plug....with Permatex....same thing....would NOT stop leaking.

So.....I got a nice clean second 1/4 inch Brass Plug and applied Blue Loctite over night before refilling radiator. NO LEAKS.

[Demps]

Check the water pump weep hole. The belt can sling the coolant all around.

Ted

[billschroeder5842]

Thanks for the suggestions, I'll check them.

I'm going to dig around tomorrow a bit and see if I can find the problem, before I tackle the whole hose mess. My guess is that the hole is small and just started so it won't leak (lots) until under pressure.

The lower hose seems to rest on the frame and may have worn through after time?

[HAWAIIZR-1]

Bill,
Besides all the other recommendations, if I can suggest my best friend the digital inspection camera.

http://m.harborfreight.com/digital-inspection-camera-61839.html?utm_referrer=direct%2Fnot%20provided

It is amazing where you can get to and see with this. It has a mirror, hook, and magnet too. Handy for leaks and getting dropped bolts and stuff. I know Cliff has one for sure.


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[RussMcB]

I bought a Stant coolant system pressure tester decades ago and it has been my best tool investment ever, I can't tell you how many times I've used it and it always helps.

https://images.thetoolwarehouse.net/images/Product_Images/STA/STA-12270.jpg

Craig, thanks for this suggestion. Looks like I might have a new favorite tool. :-)
Bill,
Besides all the other recommendations, if I can suggest my best friend the digital inspection camera. [/url]

[billschroeder5842]

So, this today, I'll presure test the system---cold. Hopefully it will show me my problem.

Questions... is it better to pressure test from the radiator cap or the coolant reservoir cap?

Logic tells me that either side will work, but is there a preferred methods and why?

Thanks!

[billschroeder5842]

I bought a Stant coolant system pressure tester decades ago and it has been my best tool investment ever, I can't tell you how many times I've used it and it always helps.

https://images.thetoolwarehouse.net/images/Product_Images/STA/STA-12270.jpg

Great minds are thinking! Thanks!

[RussMcB]

So, this today, I'll presure test the system---cold. Hopefully it will show me my problem.

Questions... is it better to pressure test from the radiator cap or the coolant reservoir cap?

Logic tells me that either side will work, but is there a preferred methods and why?

Thanks!Good question. Do both hold pressure? I can't remember.

The Stant tester tests both the system and the cap(s). So, I suggest first test the radiator caps to see what pressure they release at. Then, if you find the cap releases pressure at, say, 15 lb., then pressure test the system at 2-3 lb. higher.

By watching the needle (how fast it drops), you'll also see if you have a big or small leak.

[secondchance]

Don't over pressurize. One of WAZOO car had a blown heater core which MAY have been the result of over pressurizing at the dealer service looking for coolant leak.
Heater core is not fun to replace.

Another possible leak area is radiator plastic tank (assuming you still have OEM radiator). These typically crack about 1/3 way down from the top.

[RussMcB]

Good suggestion. That's why I test the cap pressure first. No reason to test at 20+ lb if your cap releases at 12 or whatever.

[billschroeder5842]

Well I just checked the pressure (got it up to 19psi) from the top of the fill reservoir--- no need to do anything else as I saw that "drip-drip drip" from the radiator.

Looks like I have a radiator repair to attend to...

So any suggestions on whether to repair what I have (I know there is the plastic/aluminum issue) or just upgrade to a full on new one?

Also, any tips on removal and installation? I'm pretty handy BUT I'm considering having it done as the shop manual makes several references to putting the car up in the air and I only have a simple garage jack.

Thanks!

[Mystic ZR-1]

Summit Racing Equipment
www.summitracing.com
DeWitt Aluminum 2 row direct fit
DWR-1139090M
$529 w/free shipping
(everyone has the same price, might as well get the free shipping, thanks Yun!)
just ordered one the other day, should be here this week

[Dynomite]

Well I just checked the pressure (got it up to 19psi) from the top of the fill reservoir--- no need to do anything else as I saw that "drip-drip drip" from the radiator.

Looks like I have a radiator repair to attend to...

So any suggestions on whether to repair what I have (I know there is the plastic/aluminum issue) or just upgrade to a full on new one?

Also, any tips on removal and installation? I'm pretty handy BUT I'm considering having it done as the shop manual makes several references to putting the car up in the air and I only have a simple garage jack.

Thanks!

Relatively easy to remove Radiator.......you need a jack you can get under center of frame just in front of engine (place jack pad directly under the front of that frame having the vertical section)...with flat 2x6x6 inch wood on top of jack pad. Jack up so front wheels about 8-10 inches off ground and place jack stands under each front A-arm.

If stock radiator I would replace with Aluminum......(Ron Davis, Fluidyne, other).

See Item #2 Blocking TB Coolant, Fluidyne Radiator and Thermostats (http://www.corvetteforum.com/forums/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp-12.html#post1590759179)

What you save doing this yourself you can buy a very nice Aluminum Floor Jack from Harbor Freight.....

2 Ton Aluminum Floor Jack (http://www.harborfreight.com/automotive-motorcycle/floor-jacks/2-ton-aluminum-racing-floor-jack-with-rapid-pump-62247.html) for about $130. I bought the 3 ton Aluminum Racing Floor Jack for the lift height of 19 inches. You can get the 1.5 Ton Aluminum Racing Floor Jack for $80 which I think will work also.

If you drive onto a couple 2x12x12 inch wood under front wheels you can easily slip this jack under the front skirt with flat 2x6x6 inch wood on top of jack pad.

[BigJohn]

Summit Racing Equipment
www.summitracing.com
DeWitt Aluminum 2 row direct fit
DWR-1139090M
$529 w/free shipping
(everyone has the same price, might as well get the free shipping, thanks Yun!)
just ordered one the other day, should be here this week



Or 10,580 Pepsi cans!

[mike100]

The other tip for all C4's is to trim the tab of the shroud where all the a/c and oil cooler lines converge. Then it lifts off without so much prying and bracket removal. Tip #2 is to cuss and cry removing the 6 tiny sheet metal screws that connect the shroud duct near the air inlet way down where they are hard to reach. when you put it back together, reverse the speed nut clips and screw the screws from the inside of the front air inlet rather than the original way where you reach them from the engine bay. I got away with using 4 out of 6 screws and can take them out in a couple of minutes.

[Dynomite]

The other tip for all C4's is to trim the tab of the shroud where all the a/c and oil cooler lines converge. Then it lifts off without so much prying and bracket removal. Tip #2 is to cuss and cry removing the 6 tiny sheet metal screws that connect the shroud duct near the air inlet way down where they are hard to reach. when you put it back together, reverse the speed nut clips and screw the screws from the inside of the front air inlet rather than the original way where you reach them from the engine bay. I got away with using 4 out of 6 screws and can take them out in a couple of minutes.

Forgot about those 6 screws....I think they have 7 mm heads...I remove the two bottom from underneath and the single top screws from above. That is a great tip on reversing the clips :handshak:

I did mention the six 7 mm screws in the Link.....but did not mention the difficulty ;)

See Item #2 Blocking TB Coolant, Fluidyne Radiator and Thermostats (http://www.corvetteforum.com/forums/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp-12.html#post1590759179)

[Mystic ZR-1]

Or 10,580 Pepsi cans!

Could melt down that many cans and
make a radiator...

[BigJohn]

Could melt down that many cans and
make a radiator...

Yes,where do you think they get the Aluminum?

[billschroeder5842]

Okay.... I'm going on in! No shop for me!

I started the project and am following the FSM with a bit of common sense improvise. I decided that if I pace myself, I SHOULD have it done by next weekend with a couple of hours a night. It will give me the satisfaction of doing it plus, it allows me to clean cracks and crevices and such. Its that "nobody does it like you do thing..."

First glitch... I have the upper radiator shroud/support all loose, but the bottom mounting bracket on the passenger side is getting hung up on the AC lines and there does not seem to be enough "give" to work around it.

Now, I can't believe that I have to disconnect the AC lines and the oil cooler lines? Stupid engineering! The FSM manual said nothing. What am I over looking?

Any tips?

[Dynomite]

Okay.... I'm going on in! No shop for me!

I started the project and am following the FSM with a bit of common sense improvise. I decided that if I pace myself, I SHOULD have it done by next weekend with a couple of hours a night. It will give me the satisfaction of doing it plus, it allows me to clean cracks and crevices and such. Its that "nobody does it like you do thing..."

First glitch... I have the upper radiator shroud/support all loose, but the bottom mounting bracket on the passenger side is getting hung up on the AC lines and there does not seem to be enough "give" to work around it.

Now, I can't believe that I have to disconnect the AC lines and the oil cooler lines? Stupid engineering! The FSM manual said nothing. What am I over looking?

Any tips?

Yes disconnect oil cooler flange one bolt on oil cooler .....hardly any oil will come out if not run for couple hours.....then raise drivers side clear and high....with drivers side clear and high bend flange past AC lines.....then off

[billschroeder5842]

The other tip for all C4's is to trim the tab of the shroud where all the a/c and oil cooler lines converge. Then it lifts off without so much prying and bracket removal. Tip #2 is to cuss and cry removing the 6 tiny sheet metal screws that connect the shroud duct near the air inlet way down where they are hard to reach. when you put it back together, reverse the speed nut clips and screw the screws from the inside of the front air inlet rather than the original way where you reach them from the engine bay. I got away with using 4 out of 6 screws and can take them out in a couple of minutes.

Thanks- I've completely embraced the "cussing portion" as I'm a Navy man and my 26 years of service (still in the reserve!) have given me a colorful vocabulary.

The six little screws did not give me much difficultly AFTER I removed the coolant container and the Air pump. PITA. I will reverse the screws for assembly.

AS mentioned earlier, I did remove the oil cooler and was able to get the shroud off but I cracked the casing and broke on of the mounts.

Yes, I will do a bit of triming on the Shroud. I'm not fighting that one on the way together.

I'm now removing hoses. 1/3 of the way done, so tomorrow finish the hose removal and start the cleaning of all the parts, radiators fins... etc. The previous owner allowed the oil cooler to leak for what appear to be YEARS. Lots of oil cleaning on the passenger side.

My Navy vocabulary will be fully exercised over the next few days.

Then I need to fin

[RussMcB]

Sounds like you're doing a pretty good job tackling it. I remember it was a tougher job than I expected. I recommend not having a deadline (like next weekend), and work on it until it starts to get frustrating, and take a break.

I didn't notice earlier - Are you installing an aftermarket radiator? If yes be prepared for a little extra work. IIRC, the inlet and/or outlet of my afternarket rad was bigger than the hoses I bought, and it took some effort to get them on. Getting the fan and shrouds back in place were tough, too. I think I dropped the lower (PS?) cooler to have more room. Tight spaces.

Good luck. You'll have good peace of mind when it's done.

[billschroeder5842]

I recommend not having a deadline (like next weekend), and work on it until it starts to get frustrating, and take a break.

I didn't notice earlier - Are you installing an aftermarket radiator? If yes be prepared for a little extra work. IIRC, the inlet and/or outlet of my afternarket rad was bigger than the hoses I bought, and it took some effort to get them on. Getting the fan and shrouds back in place were tough, too. I think I dropped the lower (PS?) cooler to have more room. Tight spaces.

Good luck. You'll have good peace of mind when it's done.

No radiator decisions yet, I'm not that far, but I need to have that figured out in the next day or so-- hoses from Jerry's arrive on Wednesday!

It is tough for me NOT to have a schedule; it is the Navy in me:

Today- Prep, organize, disassemble, pull shroud, fans and whine on boards begging for help and sympathy.
Monday- disassemble hoses and start cleaning. More whining but with snarky tone. Order Radiator, cringing at price.
Tuesday- More, endless, mind numbing cleaning. Less complaining in proportion to beer consumed.
Wednesday- Finish cleaning, assembly prep and begin on hoses assembly. Slowly. Glacial pace. Debate on hose clamps on if to use factory or worm clamps. Worms clamps will probably win.
Thursday- More assembly. Finish hoses, thermostat install and shroud trimming. Possible fan install?
Friday- Install new radiator, attach final hoses and thermostat. Fill up with new fluids and pour new antifreeze too.
Saturday- Bolt up nonsense and fix everything I broke. Double check and feign shock at how much I missed. Apologize to wife for being "emotionally unavailable" all week, but really not mean it.
Sunday- Pray for the benevolent Gods of FSM process and Fire her up. Happy dance and take her for a ride.

See? What could possibly go wrong? This looks good on paper and Mr Murphy is on board with this plan.

[mike100]

Well, you're gonna make that cars yours. The same thing happened to me when I put a low mileage car back into regular service- lots of small stuff broke.

[DRM500RUBYZR-1]

No radiator decisions yet, I'm not that far, but I need to have that figured out in the next day or so-- hoses from Jerry's arrive on Wednesday!

It is tough for me NOT to have a schedule; it is the Navy in me:

Today- Prep, organize, disassemble, pull shroud, fans and whine on boards begging for help and sympathy.
Monday- disassemble hoses and start cleaning. More whining but with snarky tone. Order Radiator, cringing at price.
Tuesday- More, endless, mind numbing cleaning. Less complaining in proportion to beer consumed.
Wednesday- Finish cleaning, assembly prep and begin on hoses assembly. Slowly. Glacial pace. Debate on hose clamps on if to use factory or worm clamps. Worms clamps will probably win.
Thursday- More assembly. Finish hoses, thermostat install and shroud trimming. Possible fan install?
Friday- Install new radiator, attach final hoses and thermostat. Fill up with new fluids and pour new antifreeze too.
Saturday- Bolt up nonsense and fix everything I broke. Double check and feign shock at how much I missed. Apologize to wife for being "emotionally unavailable" all week, but really not mean it.
Sunday- Pray for the benevolent Gods of FSM process and Fire her up. Happy dance and take her for a ride.

See? What could possibly go wrong? This looks good on paper and Mr Murphy is on board with this plan.

You need to do it differently!!!!!!

Experience tells me that far more consumption of beer than simply on Tuesday is in order so as to properly complete this task.
:mrgreen:

Marty

[HAWAIIZR-1]

I bought a Stant coolant system pressure tester decades ago and it has been my best tool investment ever, I can't tell you how many times I've used it and it always helps.



https://images.thetoolwarehouse.net/images/Product_Images/STA/STA-12270.jpg



Craig, thanks for this suggestion. Looks like I might have a new favorite tool. :-)


Russ,
You're welcome and thanks for the reminder about the Stant tester. I had one way, way back and not sure where it went. I will order one of these and add to the tool box. With the camera you will be amazed with what you can find; especially under the motor on the frame and in cavities and leaks in weird places.


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[billschroeder5842]

**UPDATE**

And a question...

I'm on target my self imposed schedule so far: shrouds off, radiator out, hoses off and F-Bombs a flying. So far it has been pretty straight forward with the exception of the lower radiator hose; it is just damn difficult to get a hand on.

I started cleaning yesterday and got reasonably far. I'm fixing the after effect from a leaky oil cooler hose that the previous owner left unattended for YEARS. More cleaning tonight and then should be ready for re install.

Mr Murphy may intervene with my parts deliver schedule. I'm expect hose today and radiator tomorrow. We will see as this mouse has best laid plans that could go wrong...

I replaced the cooling hose set up a couple of months ago and it has been great- good fitment and no leaks! I did remove the system to take the radiator out as the shroud was bumping into it.

Questions:

Can I can reuse the current "O" ring rubber gaskets or are they shot after one use? If I can reuse, I'll take them out, clean, put a dab of lithium grease (to hold them in place for installation) and re install.

If I need to replace, are these rings a pretty stock item that I can pick up at a hardware store?

Second... can anyone give me tips on ease of installation of the lower radiator hose? It is super tight and I have a feeling I'll get stuck?

Third, any best practices on filling the radiator/hoses so I don't have air lock? Also, any recommendations on radiator fluid? I think I have the generic green stuff.

BTW... I am getting full supervision from Kaiser and Panzer my faithful car buddies.

Thanks!!!!

[RussMcB]

Can I can reuse the current "O" ring rubber gaskets or are they shot after one use?I reused mine without issues.

[mike100]

I use Autozone standard "green" coolant. It has been known to be of good compatible conventional chemistry.

lift the passenger side of the car really high when filling the coolant- this pretty much does the trick to burp out the air bubble you get at the water pump.

I think I had to remove the mounting bolts for the thermostat housing to be able to pull it back and replace the hose. On mine, I took it to the store and found that a 4.2 V6 f150 hose has a straight section the same diameter as the LT5 lower...so I made one out of that as mine was swollen and old. I was able to reuse all the other hoses (I even have spares from another member so I'm not sweating it on them).

[billschroeder5842]

On mine, I took it to the store and found that a 4.2 V6 f150 hose has a straight section the same diameter as the LT5 lower...so I made one out of that as mine was swollen and old.

Thanks- I ordered a full new set from Jerry's--- a silicone set.

I'll look at the thermostat and see if removing it makes sense in my situation.

Thanks!

[billschroeder5842]

I installed the hoses last night. A little silicone lube on the inside of the hoses (they arrived on-time; thanks Jerry!) and the fittings and made it easier to install.

I'm using the "old" hose clamps instead of getting all new "worm" clamps. However the top of the bottom hose near the water pump had a worm style, so I cleaned, lubed and reused.

So, here is a question about my latest paranoia... can you "over tighten" a worm clamp on a water hose?

The hose near the top of the water pump is at an insanely weird angle and super tight fit for my hands. I could only get a 1/4 drive ratchet on it turning is about 1/8 at a time and the ratchet it slipped off many times falling to floor.

I had to contort my body like a Cirque du Soleil water dancer so I have no "feel" for how much was actually torqued (or over torqued??) as I kept going until the head of the clamp would spin no more and the socket slipped a bit an actually got wedged/stuck on the head as the angle changed. A small tap-tap with a hammer loosened it up. I quit after that.

Am i good or do I need to re-contort and loosen a bit?

Radiator (should) arrive tonight and install starts. If all goes well, radiator install, hoses connect, oil line re attached and shrouds in place.

Fingers crossed for the weekend--- predicted to be 70 on Sunday!

[Mystic ZR-1]

Summit Racing Equipment
www.summitracing.com
DeWitt Aluminum 2 row direct fit
DWR-1139090M
$529 w/free shipping
(everyone has the same price, might as well get the free shipping, thanks Yun!)
just ordered one the other day, should be here this week

Radiator showed up yesterday, almost
too pretty to install! 😀

[BigJohn]

Radiator showed up yesterday, almost
too pretty to install! 😀

Bring it Saturday for SHOW AND TELL!

:cheers:

[billschroeder5842]

**Voo doo time**

I have the whole system back together, ready to fire off and check. What a PITA. I have about 15 hours on this project (I admit to having ADHD and vectoring off on "side projects" as long as I'm all elbow deep and things are apart.) All that I have left to do is connect the battery and turn the key. Frankly the biggest time suck was removing the original hoses that seemed to fused on the pipe connections. Cleaning also ate a bunch of time as I could NOT just put everything back together dirty,

Because I'm superstitious, I'm going to wait till morning. If something goes wrong, I'll be up all night fuming. Tomorrow I'll have all day to fix it, (but fuming non the less) and beer will help offset the pain. My neighbor David has a '96 GS so he can console me.

I've pulled out my chicken bones, bat wings, red wine and have begun chanting.

[Roadster]

You should be fine, as you always had good success with keeping your 82 in great condition, I'm sure the ZR-1 will be just as successful...
Lol....you might not even sleep tonight.....I would have to fire it up now...lol

[billschroeder5842]

You should be fine, as you always had good success with keeping your 82 in great condition,.....I would have to fire it up now...lol

Thanks for the vote of confidence! Tomorrow I'd double check everything and then flip the key.

Fortunately my wife and I are recent empty nesters (but with two German Shepherd and three cats) so a shared bottle of merlot allows me to reflect (or be lazy) and plan for tomorrow.