Radiator Leak (?) (1984 VF700F)

Stopped at a gas station today and found coolant pouring out of my bike, but am not totally sure where/what it’s coming from. It seemed to be coming from the hole in the first attached image, but I also noticed what seems like a missing tube in the second image but I’m having difficulty finding exactly what it is on parts diagrams. The leak is pretty horrible and just about drained all of my reserve coolant, so any help is appreciated.

 

Have you recently "topped off" your coolant res tank? Was it a hot day? Sounds like your rad cap released some coolant to the res tank and it over flowed out of the tube that it is designed to do.

When the bike is cold, the res tank should only be filled to the "LOWER" mark. Some times the res bottles are labeled with "COLD" and "HOT" lines to reflect this.

The missing tube on the swingarm just goes from the shock boot to the fitting in the swingarm. Any leak from the shock will go down that way and drip out of the swingarm, not right in front of your rear tire.

 

I haven’t topped it off recently at all, and while today was hot it wasnt nearly as hot as it has been the rest of the week where it wasnt leaking out/boiling over at all

 

How old is the rad cap? They are like tetanus shots... if you can't remember the last one and immediately tell the doctor, you're getting one.

 

No idea actually but that might be it, just bought the bike a few months ago and it’s one of the things we haven’t yet replaced/serviced

 

if you find a pinhole-sized leak JBWeld is a reliable fix.

JBJBJB three cheers

saved our cheap asses again

 

A failing radiator cap seems like a likely culprit; if it can't hold pressure, you can get steam squirting through the reservoir and making that burp coolant out of the overflow.

 

A basic coolant testing pump and some adapters will serve you well in life, and they're not expensive. I've tested many of my own vehicles' parts and those of friends. Surely worth the entry cost. Worth considering.

 

The necks on the original VF's were very prone to damage from tip overs and accidents, make sure cap and seat are not distorted. If no damage, then the cap is probably the culprit.