I smell coolant when I shut my /6 down. I can't find a leak anywhere! I'm running Evans, so there's no pressure on the system. I've been driving with the Evans coolant for months, and I've not had to add anything, the coolant level seems constant, but obviously some is getting out somewhere or I wouldn't smell it - right?

I don't recall smelling any coolant after the recent rebuild (about 5k miles ago). I notice a slight smell when the thermostat opens so I'll check the heater core (new) but I also smell it outside the car when I stop the car and get out. There are no apparent leaks anywhere that I can see. I don't see any tracks on the block anywhere nor on the radiator or surrounding area, nor from the weep hole on the water pump.

What is the most common area for coolant leaks that I should suspect? As I said, this is fairly recent rebuild, all the hoses are new, water pump is new, heater core is new, radiator (aluminum) is new. It's driving me crazy.

brian

_________________
https://tinyurl.com/yynpj4v2

Check the tightness of the hose connectors.

I usually need to retighten them after a couple of months with new hoses........

_________________
Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Ah, that's one (obvious, "duh" on me) thing I haven't checked. I've never noticed clamps/hoses loosening, but I'll sure give it a try. My experience has always been those hoses frickin' gluing themselves to the metal and having to cut them off.

Thanks a bunch,

Brian

_________________
https://tinyurl.com/yynpj4v2

Usually takes a couple of years for the hoses to become one with the pipe end..........

_________________
Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

I had a similar symptom with my 225, where I smelled it but couldn't see it. Then I went under the hood and revved the motor to see if I could sew it. Sure enough coolant shot out of the tiny hose between the head and water pump. It had developed a microscopic crack and seperated and shot coolant at the head which immediately steamed off and then made that smell. I think I could have also broken the hose trying to put it in AFTER I already put the head back on, which was dumb.

mine has a slow leak on the last stud on the exhaust manifold. closest to the firewall. im waiting for it to rust itself shut.

+1. I have seen leaking studs a coupel times. Teflon tape and RTV sealant is faster than rust. But replacing the stud or drilling out the hole and heli-coiling it is just too much work.

I checked all the hose connections, some were a bit loose, but I couldn't find any coolant. I snugged them all down, then before I started her up, I hosed everything down pretty good to wash off any residual coolant. I warmed her up and I still smell coolant.

Is the fluorescent dye for leak checking coolant OK or does it crap up your coolant? I'm running Evans, so I don't want to lose gallons of the precious stuff.

As it is, wherever the leak is, it must be slow, because I haven't added any coolant since I first filled it up and the level is still about 1/2 inch from the top of where the radiator cap seats. Also, because there is no pressure on the system, it must just be trickling out. I think my only chance of tracking this down is if I use the fluorescent dye and a black light. Has anyone tried this, and where was their leak?

brian

_________________
https://tinyurl.com/yynpj4v2

I have never used Evans coolant but you say the system is unpressurised? I'm not sure what type of cap your running to achieve this,but perhaps it's just the smell of the hot coolant circulating due to the open vent set up you have ? You could pressurise the system with a regular cap and check for leaks...I think trying to find a minor weep in an unpressurised system is going to be hard...maybe even remove this stuff and just run normal coolant for troubleshooting if you can't find a leak under pressure? By the way, I love your twin Weber setup....it's a very cool look....my next project is an Australian AP5 "Safari" wagon,basically a 1963 Canadian body wagon,I've got the Offy twin manifold and webers just sitting here patiently waiting ! Will be running EDIS ignition as well. All I need is time!

Thanks, I really like the dual Weber set up. Because mine has smaller primaries and larger secondaries, the sound it makes when the secondaries open under full throttle reminds me of a 4bbl thermoquad (though thermoquads have really small primaries compared to those big secondaries).

Yes, with Evans, since it boils at 375 degrees F, there is no pressure on the system but it is a sealed system. I'm running a standard pressure cap, 11 or 14 pounds can't recall, but you can open it when hot and watch the coolant circulate. It must be a cracked hose or a stud. The studs never came out of the block during rebuild, they looked to be "welded" in there pretty good and I couldn't break them loose, so I didn't want to maybe break them and have to tap new ones etc. It wasn't making this smell after the rebuild and a few thousand miles post rebuild, so I think it's a hose. Anyway, I'll try the fluorescent dye and a black light. Let you guys know what I find.

brian

_________________
https://tinyurl.com/yynpj4v2

Thanks for the explanation on the system...I had thoughts you may have been using a cap with no seals etc....you could use a coolant recovery type cap and just pressurise it via the overflow pipe on the radiator by using a hose connected to a small hand pump. I'm not sure what type of dye your planning to use,but be careful,best do a test to see if it is compatible with the coolant,personally I'd drop the evans stuff and run pressurised water to check things out. As a side note,I have heard of sealing issues around head gaskets when running some of the glycol mixes,some gaskets don't seem to seal these types of coolants and weeps can occur,perhaps it's worth a head gasket retorque as well?
By the way...I've just had a quick read about Evans ,it appears that having any trace of water in the system is not recommended,so I retract my suggestion about using water to troubleshoot....sure hope this stuff is worth the effort...and the cost. Hope you find the leak.

I had the same experience with Evans. I could always smell coolant around it at car shows. I was running a 7 lb cap and an overflow bottle from an F body car. I am now running plain water with Norosion. There is no smell now, but even if it leaked, I suspect there would be no smell.

This is poor science, but I do not remember smelling coolant with standard antifreeze. You can buy a cooling system pressure checker from Harbor Freight for about $90. I felt too cheap to buy one.

Sam

_________________

I think most auto parts store have the pressure tester in their tool loaner program.

_________________
Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

Great idea Charlie. Why didn't I think of that?

Sam

_________________