how do i bleed the coolant in my 91 crx with d16y7 swap? is there a bleeder valve somewhere? i read about bleeding it by putting the cap on loosely and running it till the fan comes on, but my fan doesnt come on usually at idle, the longest ive let it idle was about 10 minutes and no fan, so this way seems like it wont work very well for me. any other ways?

 

There should be a butterfly valve at the bottom of your radiator. Oh, and I would not run an engine while bleeding coolant. It does not strike me as a good idea.

 

ill check in a little bit when the gf leaves, if its there do i just unscrew it or unscrew it while its running or what?

 

I would not ever run my engine while draining coolant (but I lean on the side of caution). Just unscrew the butterfly valve and let it drain.

You could turn the engine over with the starter though, I just wouldn't let the engine fire up.

 

Passenger side rear (bottom) of radiator; a white plastic wingnut.

 

Just drain the old coolant out, refill with water.

Let it run for 10 minutes. Drain water out.

Refill with water, let it run for another 10 minutes.

Drain water out, refill with 50/50 coolant.

Done deal.

 

That's sounds like a good method... The only alteration I would make if it were my car is using Distilled Water (purchased at Kroger's for < $1 a gallon). I am a bit paranoid of tap water contaminants though (i.e. I know there is fluoride and chlorine artificially induced into city tap water).

 

Yes, distilled water.

That's what i meant.

Thanks for clearing that up for me.

 

There is a difference between draining the coolant and "bleeding"
the coolant to remove the air from the system..


Most engines will have a small fitting similar to that on a brake caliper
adjacent to the upper radiator hose in which you open when refilling
and add coolant until all the air is perged and a solid stream of coolant is expelled..
D16a6:

 

Good thread. Should already be in the FAQ though, but nice of everyone to chip in with good info. Nothing more to add but to squeeze your hoses while bleeding to help get air out.

 

Actually, I have never done anything of the sort. That's interesting to know about. Thanks for informing me 88DXCRX.

Wouldn't the air in the lines naturally drain out the reservoir tank on its own though? Whats the overall purpose (please excuse my ignorance)?

EDIT: Ignore my question, I just looked into it. I still appreciate the info, thanks.

 

can you go into more detail on how exactly to do this? like do i start it and let it warm up to op temp then take off the bolt? or what?

 

This pic shows the bleeder location on a B16:


The reason for process this is basic physics..
Air is lighter than water/coolant,so naturally it rises..

The Water also seeks its own level..
and what does that mean?

Google says:
'It means that the water level will be the same in every part of container, regardless of the container's shape. For example, if the container is shaped like a "U", the water level will be the same in both legs of the "U". If you pour more water into the "left leg," the water in the "right leg" will rise too.

(This assumes that both legs are open to the air. If one leg is sealed off, it has an effect on the air pressure inside; and in that case, the water generally WON'T seek its own level.)'


So,when you start to fill the radiator,it fills from the bottom to the top
which allows an air cavity to form and become trapped inside the engine.

In order for the fluid to occupy the same space as the
air,the trapped air must first be removed/bled off to allow fluid to
fill the same space..

So,with the engine cool and not running..Add as much coolant as the system will take,
Then you loosen the bleeder allowing the trapped air to escape as the fluid is added...

The more fluid you add,the more air gets forced out until the system is totally full.

 

well i added fluid to top it off because it was leaking, and i didnt take off the bleeder bolt. so what do i do? do i have to drain it and refill it with the bolt off or is there an easier way?

 

No,You won't have to drain it but you
would have to find the bleeder if it has one and do as descibed above,

Or what some do is fill it up as much as possible,
then run it without the radiator cap until the thermostat opens
and then top off as needed..
(You may have to repeat the process a time or two to be sure.)

That method works, but if it has a removable bleeder that would be
the preferred method.

Look around the two locations pictured as well as the thermostat housing
for the bleeder.

 

so is just do this with with engine not running ?