A friend recently had his raptor built to a 686 by the same mechanic that did my first 686 and he is now having a problem with coolant overflowing out of the overflow tube and we would like some opinions on what could be causing this.I will explain just what happens to help find a possible cause.When we first head out for a ride the coolant level is right where it should be but after maybe fifteen minutes or so it will start to slowly come out of the overflow tube and then once we stop the coolant level will return to almost normal but will still be too high.The motor does not seem to be running hot and it runs very well except for the excess level overflowing so if anyone has any ideas before he starts replacing parts i will pass them on.Thanks.

 

It's a bad head gasket or more then likley it's the head bolts need to be re-tourqued if you havent already done that.

But first check the radiator cap to make sure it seals and if that is fine do the head bolts, guarntee you it's those babies....

 

1BADRAPTOR-Thanks for the quick response and the radiator cap is the first thing i suggested he try and he replaced it and still has the problem.Could you further explain the headgasket causing this ?

 

Perhaps the cooling system is airbound? If the headgaskets are not torqued down or leaking, they will leak combustion pressure into the cooling system.

 

Retorquing might work if not the head gasket needs to be replaced.

 

I had that same problem on my DS and it was the head gasket. A nick the size of a BB in the head gasket caused pressure from the cylinder to leak into the cooling system that caused the overflow bottle to fill up.

JMiller

 

Had the same problem with my raptor and it was a blown head gasket.

 

wow raptors have alot of problems.. in some respects i wish i would have known more before i bought.. but i guess you get what life brings ya huh?

 

i would expect to wait a few years for them to work out all of the bugs, if they even do
it took them this long to admit there is a problem with the rear brake lines leaking in air and going spongey
with all the mods you have on yours i would expect to see it broken alot, maybe the connecting rod next?

 

me 2


pinheadedjoker
a faulty after market head gasket failure has nothing to do with the failure tendencies of a machine.....that is like saying my sparks pipe falling off is cause my raptor is junk........