can rad flush cause trapped air in lines?
 

I have posted this question in another thread but just read a post which raised a question for me...

I just had my rad flushed and now it sounds like there is water sloshing around from behind where the radio/temp controls are on my 98 Civic...I read in another post that sometimes when flushing a rad, air can get trapped in the line...

If this is the case, could this be the cause of the noise?? If so, is it dangerous/problematic?

The noise was not there before and I already topped up the overflow tank with more fluid but the noise is still there..
thanks,

Anytime you open a closed hydraulic system you could let air in. So yes, it can lead to air in the system. However, after a few circulations of the coolant it should discard all the air. I don't think there is any way to bleed the system except for running the engine and adding coolant to the tank as it takes more coolant into the engine. It's not dangerous, but can cause water pump failure if it operates dry for a longer period of time. I hope you used Honda coolant, not that Prestone garbage. :tsk: Honda is the only coolant that is REALLY designed to be run in an all aluminium powerplant, regardless of what the Prestone bottle says. Honda knows Honda best, cuz as you know, in every Honda car, there is a Honda engine... :D :D

Some honda motor's have cooling system bleeders. There usually near the thermostate housing, or the hose housing on the cylinder head. You normallly don't have to use this but the odd time you get air in the system when a flush is done or if you just did some kind of work that required you to remove the coolant.

Excessive air can also make your temperature gauge rise and fall from time to time. And i agree with the use of honda coolant. If there's a small leak, the coolant will dry up at the leak point such as a bad rad or hose. prestone will not do this

i haven't changed the oil on my 98 si yet, but on my 93 it had a bleed off valve as well, and you just loosen it and let the engine run and top up fluid as it takes more in until bubbles stop coming out and it's a steady stream of fluid then you know all the air it out! as for the sloshing around behing your radio i dunno how that would have anything to do with air in your coolant system