Honda's use of coolant bleed bolts, why only them?

[SteveSRT8]

Originally Posted By: 440Magnum
Originally Posted By: SOHCman
I have always enjoyed the cooling system design from Honda that employs a coolant bleed bolt at a high point on the back of the engine. You just pour coolant into the radiator until a bubble free stream comes out the bolt and you are done. Why don't more companies/designs use one?


Every Chrysler product that's come through my family since about 1993 has had them. Usually on the upper radiator hose neck, basically a brake bleeder valve.


Mine has one, too.

I can't recall many cars that don't. But our fleet trucks don't have one. They don't need it either if you just follow the refill instructions.

 

[440Magnum]

Originally Posted By: SteveSRT8
Originally Posted By: 440Magnum
Originally Posted By: SOHCman
I have always enjoyed the cooling system design from Honda that employs a coolant bleed bolt at a high point on the back of the engine. You just pour coolant into the radiator until a bubble free stream comes out the bolt and you are done. Why don't more companies/designs use one?


Every Chrysler product that's come through my family since about 1993 has had them. Usually on the upper radiator hose neck, basically a brake bleeder valve.


Mine has one, too.

I can't recall many cars that don't. But our fleet trucks don't have one. They don't need it either if you just follow the refill instructions.


And when I said "every Chrysler product" that came through the family, I didn't consider the Jeeps. They don't have one, but as with your fleet trucks, they don't need one. The radiator cap is the highest spot in the system, and the flow tends to push the air into that end of the tank so it can escape out the radiator cap.

 

[mechtech2]

Most cars don't need them.
Some of the ones that are a bear to bleed don't have them, and should.
If a Mfr puts one on, you can be sure it's a great help - needed.

 

[Jim Spahr]

Like 440 Magnum said, in the 40's and 50's , the highest point in the cooling system was the rad. cap. Therefore, you didn't need another bleeder screw to bleed the air out of the system. Then Honda started having designs with the sloping nose for aerodynamics and looks. No longer was the radiator cap the highest point in the system. That's why they had to provide other high spots with bleeder screws to allow the air to be easily bled out of the coolant system. The same with other manuf. when they they because obsessed with the manufacturer's design.

 

[JavierG]

Originally Posted By: OVERK1LL
Originally Posted By: VNTS
Another Honda is smarter than everyone else debunked LOL


LOL! I was thinking the same thing!

"My Honda has coils on each of the plugs, why don't other manufacturers do this?"

LMAO!!!

LOL. Don't be so insecure guys. I'm sure you have nice cars too.

 

[SOHCman]

Originally Posted By: Jim Spahr
Like 440 Magnum said, in the 40's and 50's , the highest point in the cooling system was the rad. cap. Therefore, you didn't need another bleeder screw to bleed the air out of the system. Then Honda started having designs with the sloping nose for aerodynamics and looks. No longer was the radiator cap the highest point in the system. That's why they had to provide other high spots with bleeder screws to allow the air to be easily bled out of the coolant system. The same with other manuf. when they they because obsessed with the manufacturer's design.


I think you hit the nail on the head there, the sloping hood placing the radiator lower may make the addition of one necessary.

 

[mechtech2]

There are all sorts of spots that can cause bleeding problems. Heater cores and their piping are a usual problem.
But air can be trapped in the head/block, as well.

 

[artificialist]

The Toyota 1MZ engines eliminated the need for a coolant bleed screw by relocating the radiator pressure cap to the top of the engine.

 

[yonyon]

I've always liked the way bleeding works on these:
-Most Honda's. The dingleberry valve in the thermostat is a joy.
-Fords with the giant "degas bottle" pressurised reservoir.
-GM Tech 4. Remove thermostat and pour coolant in.

Nasty:
-Kia Sedona. Use a vacuum type coolant fill tool, then warm the engine up fully, then hold RPMs above 5k until the rear heater core purges. Yeah.