Do I have drain the coolant to change the thermostat

[Biodiesel300TD]

I was just reading up on how to change the thermostat on good ol' DieselGiant's page. Is it necessary to drain all the coolant to change the thermostat? I just had my coolant changed when I got my blockheater installed last month. Is coolant going to spew everywhere if I open the t-stat housing without draining the coolant?

Thanks again.
Andrew

[Big J]

I just changed my thermostat this past weekend and I lost about 3/4 gal of coolant. I guess you could use a catch pan . . . .

[Zerohour3k]

Originally Posted by Biodiesel300TD

I was just reading up on how to change the thermostat on good ol' DieseGiant's page. Is it necessary to drain all the coolant to change the thermostat? I just had my coolant changed when I got my blockheater installed last month. Is coolant going to spew everywhere if I open the t-stat housing without draining the coolant?

Thanks again.
Andrew

So long as the engine isn't hot, it won't really "spew" everywhere. I changed mine in the rain, last Wednesday. About a gallon of coolant will leak out, if you don't drain it.. so be sure to have some extra to top it off with. It's a really easy job.. just be SURE not to do it with a hot engine, or the fluid will obviously scald you badly.

[Zerohour3k]

Here's a question, though. I replaced mine, and didn't notice any "arrow" on my aftermarket T-stat. In fact, Im not 100% sure which direction I put the thing in, at. I know the 'stat is orientated properly, just not sure if it's "facing" the correct rotation. Does this really matter? The car is running at peak performance, 82-90C.. so I'm guessing I have it right anyway.

Does that arrow really mean anything? If so.. did I just get lucky?

[biopete]

I drained miy coolant down past the thermo housing to my best guess. The head of a plastic drainplug to the radiator which takes a large flat blade broke almost as soon as screw driver touched it. Lucky I could still get pliers on it. It reminded me of some VW plastic parts that crumble in the fingers.

[Pete Burton]

Originally Posted by biopete

I drained miy coolant down past the thermo housing to my best guess. The head of a plastic drainplug to the radiator which takes a large flat blade broke almost as soon as screw driver touched it. Lucky I could still get pliers on it. It reminded me of some VW plastic parts that crumble in the fingers.

Don't use a screwdriver, use a washer or a coin. Then you'll naturally apply the 1-2 Nm torque desired. - I'm not that smart to think of that, I just read that recently in the FSM.

[biopete]

Originally Posted by Pete Burton

Don't use a screwdriver, use a washer or a coin. Then you'll naturally apply the 1-2 Nm torque desired. - I'm not that smart to think of that, I just read that recently in the FSM.

Thanks for tip. Who would a thunk a drain plug with 1 Nm torque? Good lesson learned about plastic fasteners.

[meltedpanda]

Originally Posted by Zerohour3k

Here's a question, though. I replaced mine, and didn't notice any "arrow" on my aftermarket T-stat. In fact, Im not 100% sure which direction I put the thing in, at. I know the 'stat is orientated properly, just not sure if it's "facing" the correct rotation. Does this really matter? The car is running at peak performance, 82-90C.. so I'm guessing I have it right anyway.

Does that arrow really mean anything? If so.. did I just get lucky?

Yes it does and yes you did . I understand the arrow posistions thermostat for r proper air bleed

[Pete Burton]

Originally Posted by Biodiesel300TD

I was just reading up on how to change the thermostat on good ol' DieseGiant's page. Is it necessary to drain all the coolant to change the thermostat? I just had my coolant changed when I got my blockheater installed last month. Is coolant going to spew everywhere if I open the t-stat housing without draining the coolant?

Thanks again.
Andrew

partially. You can open the radiator drain and empty 2 or 3 liters until fluid level is below top of upper radiator hose (which you are loosening the clamp from anyway. Drain until this connection sucks air rather than leaks fluid.

Now, I just had a thought: what if you reached into the t-stat casting with something like a brake adjuster - something that you could push against the t-stat spring (who cares if you hurt it - you are replacing it) and let loose the several more liters that typically flood out. If I had thought of this the other day, I would have tried it and collected the fluid.