Coolant system Q's....

Ok, so I have a question regarding the thermostat and also on the water pump on the RC24...

The bike started overheating the other night and barely got me to school yesterday. After cruising home on the freeway doing 55 mph and almost getting run over several times... I figured it needed fixin! I tested everything out and the cap didn't leak, the pump turned and the fan kicked on at 190.

I shut it off when the radiator was at 215 and measured the stat temps, 195 forward and 182 behind. It was definitely not opening. I drained the coolant this morning, pulled the thermostat and tested it in the kitchen. At 190 it started to open, and at 200 it was about 1/8" open. I'm assuming that it's supposed to be much more than that, so I went to Checkers and got one of the '83 Civic ones for $8 rather than wait 3 days and pay $37 at Apache Honda.

Anyways, my 1st Q... the original has a 1/8" hole in the flange and is off centered to accomodate this. The new one is centered and has no hole. Will not having said hole and preventing most of the flow during warm up be detrimental to the cooling system?

Also, since I had it drained I wanted to check out the pump (which I knew was working fine cause I put my stethoscope to it and heard it turning). I pulled the cover and the blades are intact without damage, no build up on the casing either. However, the blades have gunk and corrosion on them that can be scrapped off with some effort. I really want to clean it up nice before putting it back together, so what is a good method to do so? Can I use solvents like carb cleaner without worrying about damaging the unit?

I know that it's a good pump cause I turned the motor with the cover off and she spun fine. It's just all the gunk I don't want to risk circulating through the system.

*after thought.... I should prob drop the radiator and make sure it's not clogged up as well....* any ideas????

 

What were you using to measure your temps if you don't mind me asking?

 

IR temp gun

 

UPDATE:

Well, this week has been total hectic & I haven't had much time to spend on the bike, which sucks cause my Contour is down with a bad alternator and the bike is my only other ride. Used my girlfriends Jeep to get to school last night and will again tonight.

On a sad note, Catherine had a miscarriage this morning after us only just finding out 2 days ago that she was pregnant. I have two daughters from a previous marriage, but this would have been our first together. Needless to say, today was spent mostly at the hospital and with her family. She is OK... a bit shaken and hurting, but doing good.

As for the bike...

I got the replacement thermostat and decided to boil it along with the old one to comparatively see the difference on how much the old one wasn't opening. To my surprise, the old one now opens fully as much as the new one does. I guess boiling a stuck stat has the effect of cleaning the gunk off and fixing it?

Anyways, I also pulled the pump off and used a mild multi-purpose cleaner I have from when I was driving trucks OTR, and managed to get most of the gunk off the blades. The body of the pump cleaned up nicely too.

I'm still concerned with the radiator itself, thinking that it may be part of the problem and has gunk build up that is slowing the flow possibly. I don't want to use commercial flushes as I remember being told that they can harm these types of systems.

What's the best way to clean out an original radiator without damaging it?

 

Sorry to hear about that Lazy, I am probably in the same boat on my cooling system with the donor engine bike I am resurrecting but the fan won't come on now when I ground it so it looks like I'll have to pull the thermoswitch and the thermostat and test them. I have no idea about cleaning a radiator such as this but you do have some instructors to ask about it.

Let us know what answer you come up with I am curious myself.

 

I spoke with my Clinic 2 Instructor who has done many years of building and rebuilding of old bikes - mainly Harely's - but he's got lots of experience with them. He told me that I did get lucky and happened to fix my thermostat by boiling it in clean water since it's opening now, and that I was on track with the gunky build up on the pump fins that there is no doubt a clog in the radiator.

He told me that if he was the one doing this type of work that he would go to NAPA or Checkers and explain to them the type of work that I was doing and have them point me in the direction of what type of flush to buy. Basically, I need "a wire pipe cleaning brush in liquid form that won't damage the interior of the radiator" as he put it.

I'm going to hold on to the old thermostat and keep it in my tool pouch holder (now empty) just in case I ever need one somewhere down along the road. I'd just feel better knowing that the new one is in there now....

 

Dukie, I was told by the SM at Apache Honda that the best way to clean out the radiator core is to dump all the coolant, flush it with distilled water and remove the thermostat. Then put in a bottle of Prestone Cleaner and top it with distilled, run it for 200 miles or so, dump it out completely and repeat the process until the liquid comes out clean and not full of contaminates... possibly 2 to 4 times.

Afterward, flush it completely with distilled and then fill it with Honda Coolant. Of course he recommended that, but I'm sure any motorcycle safe coolant will work.

I got all the stuff today, including the new thermostat gasket. Will clean it out Saturday morning. Will post results.

If this doesn't work I may have to look into sending it out to be cleaned professionally.

 

Yeah, that was going to be my final recommendation if you didn't want to DIY, just take it into a radiator shop and have them futz with it.