I'm too embarrassed to say how long it's been since the coolant has been changed, so I won't -- but I can tell it's time. No overheating really, the reserve tank's coolant just looks cruddy. I've read up on what is needed to do this, but I don't know if the drain bolt(s) need OEM washers or not. I also can't seem to find them in the microfiche parts image or list (there's bolts but they look like the radiator-to-frame ones.

A) Which bolt washers do I need in there?
B) Have you used alternate non-OEM, if so what size should I get?

Truth is I don't know if I'll need new bolts so I probably should get both bolt and washers.
Just in case...

Thanks.

F2 Radiator Microfiche Image: Ronayers.com Microfiche Honda>Motorcycle>1991>CBR600F2>RADIATOR - F2 - 91-94

 

You are lookin in the wrong place

The drain is on the water pump, which does have a crush washer to seal.

Ronayers.com Microfiche Honda>Motorcycle>1991>CBR600F2>WATER PUMP

IIRC correctly, there are also 2 drains on the case, which would have washers too.

 

I've reused the crush washer on the water pump a gazillion times. No problems. I also didnt realize there were drains on the engine itself. What I do is drain the water pump, refill with plain water, let the bike warm up to temp. Let cool, drain again. I do this about 3or4 times. I do this in the spring to get the antifreeze out, from winter time, then only distilled water and "water wetter" for summer time track days.

 

OK, thanks for replies. I was looking in the wrong place, and/but here is what my Haynes manual says at the end of the process:

"Fit new sealing washers to the drain bolts and install them in the oil cooler and pump cover..."

I see the water pump in the diagram but which is the "oil cooler"?
Also, Ive been told that using about 1 qt. of vinegar as flushing compound mixed with the water. Da or nyet?

 

The oil cooler is that vertical rectangle thing behind the exhaust header. Never heard of the vinegar thing but they say to run white vinegar/water mix thru your coffee pot to clean it out. If it was me and only flushing the radiator I wouldnt mess with the oil cooler, just the drain at the bottom of the water pump. You should also be able to find little copper washers at a hardware store like Ace of True Value. Thats all they are is soft copper washers that will smash a little when tightened to help prevent leaks.

 

OK, thanks for all of your replies and further info -- and the copper washer at hardware store is a great tip :)

 

I've done white vinegar/distilled water flushes on my cooling system before. It takes off surface corrosion, much the same way it makes pennies shiny again. You just need to flush it out with more distilled water before you put the new coolant in. It's not strong enough to chew through metal but, in theory, if you have a lot of corrosion on your radiator, that might lead to weak spots that leak after vinegar treatment.

That being said, I did a vinegar clean and flush, filled up with engine ice and the cooling system has never worked better.

 

Alright, thanks for the observation on the vinegar thing.