Advice needed: antifreeze smell

[97Valk_CT_Euless]

First, I really appreciate this forum. I've learned a lot from you guys just reading posts. You've kept me out of a lot of trouble and I thank you for it.
I'm starting to smell a light, brief whiff of antifreeze after riding to work and after getting home. (20 miles each way) short rides dont seem to cause it even i the bike gets good and warm. Disappears almost instantly but it's real. Can't find any evidence of a leak in the usual places (longtime shade tree car mechanic). No drips under the bike, no puddles on the engine or frame that I can see, no "trails of evidence" where coolant has run and evaporated. doesn't seem to be losing coolant at any rate I can tell. Doesnt appear to be leaking from the reserve line connections or tank. Changed the coolant 3k miles or so ago, replaced with Honda. Just started noticing this smell since it cooled off. First time was my coldest ride in (upper 30's) and seems to be happening regularly now but not worse, if you know what I mean. Just a whiff when I get off the bike and it's gone.  Any ideas? I intend to change that 15 year old radiator cap but I haven't found that gage-cap that i'd really like to have (and have seen but the guy just remembered getting it "online"). No evidence I can see that the cap is leaking but it is 15 yrs old... I appreciate any thoughts and ideas.

[MP]

1st place to look is the cap.  Take it off, bend the tabs just a touch, so that the cap fits tighter.

[sandy]

If your cap is bad, you'll see evidence around the neck. The cold weather smell is usually from two tubes that press into the block below the T'Stat. O rings seal them and the O rings tend to leak when they contract in the cold. Follow the waterpump outlet hose to a split and into the tubes. Mine have leaked 2-3 times in all the years I've had the bike. Sometimes the hose coming out of the T'stat housing leaks and just needs tightening. A long small screwdriver usually can reach it from the bikes left side.

[Ricky-D]

I would suggest to do nothing but continue to look for any signs of a leak.

The largest contributions of leaks come from a loose hose clamp that is located behind the radiator. That's the top hose from the radiator at the other end.

Smelling is only indicating the presence of coolant and does not mean any kind of major leakage, especially in view of no coolant on the floor.

I would not automatically condemn the cap!

You can insure the return hose to the plastic reservoir tank is clear simply by taking it loose and blowing thru it. Be especially careful to not put undue stress on the barb since it can break off with little force.

***

[97Valk_CT_Euless]

Awesome guys. I'll check all this out and post back what I find. Thanks again.

[Chrisj CMA]

Awesome guys. I'll check all this out and post back what I find. Thanks again.

You did not state the year of the bike, but If its a 97 (your avatar) then what you are smelling is perfectly natural for these old Gold Wing type 1500 motors.  The water pipe fittings have little odd shaped o-rings in them, they get hard, and let a tiny bit of coolant sprits through.......unless you see a puddle theres probably nothing you can do short of replacing all the o-rings.  I have a set ready to go, but the smell on my '97 has never gotten an worse since I first noticed it about 5 years ago

[Skinhead]

I have had an intermittent coolant leak on my IS twice.  Both times it was the lower clamp on the upper radiator hose.  This clamp is a little hard to get to as it is behind the radiator.  If you are lucky, the clamp may be oriented so that you can reach it with a long screw driver or socket and long extension.  If you're not lucky, you may have to drain and remove the radiator and tighten the clamp.  One piece of advice, the OEM Honda clamp is a 1/4" wide, flimsy clamp that is prone to losing it's clamp load.  I replaced mine with a good quality clamp that is 1/2" wide, this is a more robust clamp that can be maintain a higher clamp load.  A further improvement would be to find the proper size Spring type clamp, (the ones you expand to install with pliers)  these maintain their clamp load better than the clamps you tighten with a screw.

If you remove the radiator, be sure BOTH of the mounting pins on the bottom of the radiator are properly engaged when you reinstall it, if they aren't, there is a chance that the mounting pin can rub through the radiator core, which would be a VERY expensive repair.

[mmurffy03]

not to sound to obvious but this happened to a friend and all it turned out to be is that he had not put the small swrew back in the cap after removeing it to top off the antifreeze after replaceig it the smell went away even though there was no sign of any leak

[97Valk_CT_Euless]

Thanks for all the good advice. I'll check it all out when I get back home tomorrow. The screw is in place. Thanks again everybody and I'll post what I find.

[97Valk_CT_Euless]

BTW Chrisj, it is the 97. Your statement makes me wonder, is the 97 a different engine?  I was under the impression they were all the same until the Rune. But, I'm very much still learnin 'bout my baby and her sisters out there. 

[9Ball]

not to sound to obvious but this happened to a friend and all it turned out to be is that he had not put the small swrew back in the cap after removeing it to top off the antifreeze after replaceig it the smell went away even though there was no sign of any leak

The small screw doesn't plug any hole through to the radiator....it only secures the cap in place and is on the outside of the neck.

He probably had a loose cap and by checking it's tightness and replacing the set-screw the leak went away.

Only a coincidence....

[Ricky-D]

I'd toss the screw!

It's not needed!

***

[9Ball]

I don't agree with tossing the screw....if nothing else it serves as a security measure to keep some vandals from walking off with your radiator cap and leaving you stranded.

I had a minor problem with tampering in Sturgis after parking the bike at the HD dealer...it's a little insurance and my opinion is to keep it.

YMMV

[fordmano]

I'd toss the screw!

It's not needed!

***

Ricky-D, I am with you 100% on this one.
Maybe not the same rational but I agree with your suggestion... ( I guess I don't know your reasoning?? No big deal).

When I first got my Valk, dropped it off at the dealer for full check out fluid swap out first general maintenance and a "FULL carb rebuild" When they called me back they said they needed to replace the radiator and the cap since the cap was bad and the radiator was some how been damaged before I left it there.... NOT. They did not know they needed to remove the screw before removing the cap and boogered up the filler neck. I said NO and rode it home with a very slight leak. Took the cap off tapped, bent and filed the neck back into shape and put stock cap back on. Never another leak since then and thats been almost 7 years.
Since then I have replaced the cap with a new stock Chrome one then added a Billet aluminum cover.. Still no leak. and NO screw no more....

I think the possibililty for vandilism damage would be MUCH greater if the screw was in place while the cap is being turned by said vandal... Just my opinion, but what do I know I grew up in a ghetto (like nighborhood) where LOTS of silly vandalism exists.

[9Ball]

that's why they make vanilla and chocolate ice cream.

You're only going to slow down someone with larceny in their heart...and there are too many fools walking around to make things fool-proof.

[97Valk_CT_Euless]

Just feeding back...  I pulled the cap (easy things first..) and apparently hadn't noticed before that the surface was buggered up.  Also a pretty good burr from where someone had tried to install the screw int he the wrong place (cap not all the way on) in the past.  crammed a paper towel in the top to catch the filings and gently used a fine file to clean it all up.  Also noticed the outer gasket on the cap starting to crack, but it's outside the sealing surface.  Also carefully bent the cap tangs in slightly to tighten the cap.  Didn't find any evidence of leakage in the pther points mentioned, but when I get back down below the tank, or if the smell comes back, I'll check that closer.

This morning I didn't notice the smell.  So far so good.

Thanks for all the good pointers.

[9Ball]

good job...

[scoot]

When my upper hose was leaking by the neck, it only leaked enough to smell. The coolant would actually evaporate before leaving any real telltale signs. I was eventually able to see a little green corrosion trailing down the side of it. Get a good light, and look up in there.