bleeding an s50 w/ a mishi rad....

[JRKOUPE]

hey fellas...

Ive searched and read for a while now....

but on a swap that has a mishi rad /s50,..what is proper bleed procedure?..

this set up has a remote res/overflow line..and the mishi rad has a "bleeder " hose at upper lt( drvr side)

do I keep remote res cap off?...do I remove bleeder hose from rad?....not sure.

tia

jrk

[RobertK]

I've mentioned this in another thread but generally what works great for me is drill 1/4 hole in my thermostat and install it with the hole toward the bottom of the engine. Before adding coolant I jack the front of the car up about 1~2ft to help air move toward the front of the engine.

When I fill up the cooling system I detach the upper rad hose from the radiator and use the top part of a plastic milk jug as a funnel to pour coolant into the system. I stop when it begins to pour out the upper hose connector on the radiator, clamp the upper hose back on, and then top off the coolant reserviour.

Start the engine (assuming its cold) and run it a few minutes with the heat on full blast and the cap off the coolant reserviour. Rev it up to 3~4k a few times and add additonal coolant as needed. Once your temp gauge gets to 1/4~1/2 mark install the cap. You're done.

[10Toes]

Filling the block through upper hose is the way to go.

[golde30]

Why is it better to have the hole on the bottom side as opposed to the top side?

[nrubenstein]

With a 1/8" hole drilled at the top, I just pour in from the reservoir and it fills out fine on its own. Your way seems very complicated for no return that I can see.

[Rugbyfan]

Question, With that hole, wouldn't coolant bleed out from time to time when you're driving? I'm going to replace my thermo soon, and I have no bleed screw so I'm wondering if this will help at all.

[giantkeeper]

With a 1/8" hole drilled at the top, I just pour in from the reservoir and it fills out fine on its own. Your way seems very complicated for no return that I can see.

this, done and done!

[Adrian_Visser]

The purpose of drilling a hole in your thermostat is to allow trapped air bubbles out of the closed engine side system before the thermostat opens. Air is lighter than water that is why you drill the hole at the top. 1/4" is also quite a large hole and could ultimately cause problems getting the engine up to temp in cold weather.

[Rugbyfan]

The purpose of drilling a hole in your thermostat is to allow trapped air bubbles out of the closed engine side system before the thermostat opens. Air is lighter than water that is why you drill the hole at the top. 1/4" is also quite a large hole and could ultimately cause problems getting the engine up to temp in cold weather.

My mistake, I thought the hole was being drilled in the Thermostat housing. Drilling a hole in the thermostat itself makes more sense I suppose.

[Adrian_Visser]

My mistake, I thought the hole was being drilled in the Thermostat housing. Drilling a hole in the thermostat itself makes more sense I suppose.

Some people will put a bleeder screw in the housing too a la m20 Thermo housing. My s52 had one installed on it. I never used it though.

[RobertK]

Never had any problems with temps, some of the French made thermostats come with a 1/8 hole already in them with a little brass check valve. You can place it anywhere really.

Not a big fan of drilling and tapping my TS housing because it looks tacky and I would really prefer to bleed coolant away from the engine where its not leaking onto my belts and accessories.

Been using upper hose method for years, works great on E46's too.

[Adrian_Visser]

Yeah I wouldn't be too keen on drilling holes in my cooling system either, the one on my car is seized in there and doesn't work anyway.

[JRKOUPE]

fellas....great info here....thanks for teaching me...lol

Im in process of tracking down some coolant seep issues and Im secretly hoping its not a hg.....that could be costly and it would surely end my track season.

oh......is a bit of pressure in the coolant res normal ?.....I mean, after car is shut down while hot, how long would /should it take that once you open coolant res cap there is no hiss whatsoever?.....
I would think that some pressure build up in the res is normal....but I also know that if it remains for a long time it could be indicative of combustion gas buid up....and a suspect blown hg.

[RobertK]

Pressure from expansion of coolant is normal but not to the point where it spews out when the cap is tight on the expansion tank.

On swap cars the heater hoses seem to be the PITA to seal up if you are using used hoses on these cars.