1975 gt750 coolant leak from overflow

[keystoker]

hello everybody i have a question. i have a 1975 gt750 that i have owned for 10 years and every year when the bike sits over the winter and get taken out for the spring i run into this problem. i blows coolant out of the overflow tube. it is only about four ounce but i suspect some is in the cylinders too. i have replaced the head gasket and torqued the head properly. have also used a 50/50 antifreeze mixture with alumina seal. i usually but about 1000 miles a year on with no problems. but it makes me nervous. do i have anything to worry about or is this normal condition?
all help is greatly appreciated

[GT750Battleship]

Hi,you have not overfilled the reservoir tank have you ? This should only be just above the first line on the plastic bottle & the coolant in the filler neck should be just below the intake for the bottle !I think the plastic tank should have around 5ml in it or a bit more ? My bike lost coolant out the overflow some time back..it proved to be a blown head gasket ! Always use a genuine Suzuki gasket..as "aftermarket" don't seem to work,from my experience.
Cheers,
Roger

[keystoker]

the coolant was not over filled. it was just under the lower line on the overflow bottle. i did use an aftermarket head gasket that was Japaneses made and seemed to be good quality. but the problem only occurs in the spring when the bike is taken out of storage. i guess my main concern is i don't want to ingest coolant on a long trip and cause any internal motor damage.

[tz375]

That suggests that it is something that happens during storage rather than a head gasket leak when running.

As to what that is, is less clear. It sounds like it's temperature related though. If there is air in the system, maybe on that first start it warms up and pushes excess fluid out.

[oldjapanesebikes]

+1 to Richard's comment. If the head gasket had actually failed, then normally it would be obvious. They don't usually fix themselves.

[Suzukidave]

You didnt comment on the shape the radiator cap is in ? Do you have a replacement cap you could try .