[V8bait]

Originally Posted by dauble2k5

Just finished this job, man that was simple. The bottom hose clamp was a challenge to get loose, but overall, 20 mins and I was done. Bleeding process was unbelievably simple.

Thanks for the info!

People over complicate these cars based on the badge and the odd hose clamps.

[SM335i]

Originally Posted by dauble2k5

Just finished this job, man that was simple. The bottom hose clamp was a challenge to get loose, but overall, 20 mins and I was done. Bleeding process was unbelievably simple.

Thanks for the info!

Can you post the bleeding process you did, wondering if its the same as for water pump and thermostat.

[dauble2k5]

SM335i - It's simple. Fill the tank to the top (over the MIN/MAX fill line) and close the tank. Unscrew the bleeder screw next to the cap and upper hose a quarter turn and get a rag handy. Turn the car to the ON position (but not running), turn the heat up to 84 (the warmest you can make it) and low fan, make sure the wheel is turned to heat and not cool, then press the gas pedal for 5-6 seconds. You should start to hear the water pump spin up and will start to see bubbles come from the bleeder screw.

My water pump cycled five times I think. After this, I checked the levels and it was perfect. You can bleed it again just to double check, but it's probably not necessary. Mine started gushing all the coolant that was in the system.. and no bubbles.

After a 15 min test drive, all was well. Checked it this morning and it was a touch low, which was to be expected. I'll keep an eye on it over the next few weeks, as if there are any other air bubbles in the system, they'll eventually work themselves out.

[BeastMode335i]

Originally Posted by dauble2k5

SM335i - It's simple. Fill the tank to the top (over the MIN/MAX fill line) and close the tank. Unscrew the bleeder screw next to the cap and upper hose a quarter turn and get a rag handy. Turn the car to the ON position (but not running), turn the heat up to 84 (the warmest you can make it) and low fan, make sure the wheel is turned to heat and not cool, then press the gas pedal for 5-6 seconds. You should start to hear the water pump spin up and will start to see bubbles come from the bleeder screw.

My water pump cycled five times I think. After this, I checked the levels and it was perfect. You can bleed it again just to double check, but it's probably not necessary. Mine started gushing all the coolant that was in the system.. and no bubbles.

After a 15 min test drive, all was well. Checked it this morning and it was a touch low, which was to be expected. I'll keep an eye on it over the next few weeks, as if there are any other air bubbles in the system, they'll eventually work themselves out.

You're welcome bro, glad you're back up and running..!

I did my bleeding pretty much the same way as you, except I wanted to fill as air was being released so I left the bleeder tightened and had removed the cap, that way I could see/hear the air being forced through the system all while watching the little bobber go down a bit.. Once it stopped going down I closed the cap, and I just checked yesterday, still at the very top

I live in So Fla so I used distilled water btw, did you use BMW Coolant..?? Also do you monitor your temps at all..?? My coolant temp seems to avg. around 180-190, wonder what's considered "normal"...

[dauble2k5]

Originally Posted by BeastMode335i

You're welcome bro, glad you're back up and running..!

I did my bleeding pretty much the same way as you, except I wanted to fill as air was being released so I left the bleeder tightened and had removed the cap, that way I could see/hear the air being forced through the system all while watching the little bobber go down a bit.. Once it stopped going down I closed the cap, and I just checked yesterday, still at the very top

I live in So Fla so I used distilled water btw, did you use BMW Coolant..?? Also do you monitor your temps at all..?? My coolant temp seems to avg. around 180-190, wonder what's considered "normal"...

Nice! I did use coolant. I had an emergency t-stat replacement on my last car, so had 1.5gal pre-mixed, which I've been using to top off mine when the car says it's low. Being in IN/OH, the weather gets pretty cold in the winter, so I have to use the blend.

As for monitoring coolant temps, I do not. I wish these cars had a coolant temp gauge on them, without having to access some hidden menu. I just watch the oil temp and continue with my drive.

How do you monitor the coolant temps? Is it something you can do on the fly?

[BeastMode335i]

Originally Posted by dauble2k5

Nice! I did use coolant. I had an emergency t-stat replacement on my last car, so had 1.5gal pre-mixed, which I've been using to top off mine when the car says it's low. Being in IN/OH, the weather gets pretty cold in the winter, so I have to use the blend.

As for monitoring coolant temps, I do not. I wish these cars had a coolant temp gauge on them, without having to access some hidden menu. I just watch the oil temp and continue with my drive.

How do you monitor the coolant temps? Is it something you can do on the fly?

Ehh, I see lol, in those climates you'd def want to stick with premixed and not use water only..

And I use the MHD app to monitor stuff and it has Coolant Temp as an option

[Flyboy161]

Well, hell! My reservoir started leaking today, right at the seam between top and bottom of the tank. Ugh! Time to see if the CPO Warranty covers it.

[BeastMode335i]

Originally Posted by Flyboy161

Well, hell! My reservoir started leaking today, right at the seam between top and bottom of the tank. Ugh! Time to see if the CPO Warranty covers it.

CPO should cover it for sure.. If not, it's like $30 on eBay with a new sensor..

[Flyboy161]

Cool. Yeah I topped off the reservoir, bled it twice. Level did not drop. All in all I probably put in 12-16 oz of antifreeze. So, we'll see. Have 10:15 appointment on Monday at the dealer

[BeastMode335i]

Originally Posted by Flyboy161

Cool. Yeah I topped off the reservoir, bled it twice. Level did not drop. All in all I probably put in 12-16 oz of antifreeze. So, we'll see. Have 10:15 appointment on Monday at the dealer

Mine held fine, until the car go to operating temp, than it would start spewing out.. I eventually took it out and played homerun derby with it against my louisville slugger haha.. The bat won

Got my replacement off eBay for the low, and it's been about a year now, no issues..

[dauble2k5]

Originally Posted by Flyboy161

Well, hell! My reservoir started leaking today, right at the seam between top and bottom of the tank. Ugh! Time to see if the CPO Warranty covers it.

That's exactly where mine started leading; at the top, where the hoses connected to the tank.

Originally Posted by BeastMode335i

Mine held fine, until the car go to operating temp, than it would start spewing out.. I eventually took it out and played homerun derby with it against my louisville slugger haha.. The bat won

Got my replacement off eBay for the low, and it's been about a year now, no issues..

As with mine, more so if I'd get on it, then I'd start smelling coolant in the cabin and find a nice surprise when I got home.

--

Ended up getting my parts at the dealership. There was a dealer where I used to live that sold parts at a reasonable price and used my CCA discount.

If it's not covered by warranty, it's maybe a 30min DIY. Hardest part is draining the tank and cleaning up all the coolant that'll get everywhere.

Good luck!

[autoart]

Fyi- Rockauto has the tank starting at $35

[Flyboy161]

Yeah. When the CPO warranty runs out I'll fix my own stuff. Until then...
Dealer replaced the reservoir under warranty today. I went ahead and did a coolant flush while I was there. Thanks all for the help

[SmellyGreek]

Can you get away with replacing the reservoir without draining the coolant from the system? Pelican Parts writeup suggests this, but it seems a bit unnecessary. I don't mind a small mess from the lower hose once disconnected, but if it's all going to come out then I want to do it right.

[BeastMode335i]

Originally Posted by SmellyGreek

Can you get away with replacing the reservoir without draining the coolant from the system? Pelican Parts writeup suggests this, but it seems a bit unnecessary. I don't mind a small mess from the lower hose once disconnected, but if it's all going to come out then I want to do it right.

Absolutely.. Just unclip the hoses, sensors, etc and you're good to swap it out.. Refill, bleed, and drive away..

[R.G.]

Need to put at least a small percentage of coolant in your mix unless you're at the track and concerned about spillage. Water+metal+heat=You're going to have a bad time.
Read up on boiling points+mixture percentages

[BeastMode335i]

Originally Posted by R.G.

Need to put at least a small percentage of coolant in your mix unless you're at the track and concerned about spillage. Water+metal+heat=You're going to have a bad time.
Read up on boiling points+mixture percentages

Local dealer here in South Florida tops off with distilled water.. I've done the same, have for 15+ years, never had an issue..

[R.G.]

Originally Posted by BeastMode335i

Local dealer here in South Florida tops off with distilled water.. I've done the same, have for 15+ years, never had an issue..

Topping off a 2.2 gallon cooling system and running straight distilled are two different things. I may have misunderstood.

[BeastMode335i]

Originally Posted by R.G.

Topping off a 2.2 gallon cooling system and running straight distilled are two different things. I may have misunderstood.

Yeah I was just talking about topping it off, as there's no reason to drain the system when changing the expansion tank..

[dauble2k5]

Originally Posted by SmellyGreek

Can you get away with replacing the reservoir without draining the coolant from the system? Pelican Parts writeup suggests this, but it seems a bit unnecessary. I don't mind a small mess from the lower hose once disconnected, but if it's all going to come out then I want to do it right.

Yes, however you will lose some coolant when disconnecting the hoses. I think I lost maybe a glass of coolant when I replaced my tank. I'd recommend putting a pan down below to catch any spillage.

[SmellyGreek]

Originally Posted by dauble2k5

Yes, however you will lose some coolant when disconnecting the hoses. I think I lost maybe a glass of coolant when I replaced my tank. I'd recommend putting a pan down below to catch any spillage.

Thanks for your and Beast's responses. A glass of coolant spilled is a favorable trade-off for not draining -- 1+ gallons, not so much. I'll have absorbant mats handy to catch any spilling liquid.

[ryan stewart]

Exact same spot as beastmode. 147k car. It happened when I was stopped in traffic. Since it was not holding pressure it was expanding and the water was above the line so it was POURING out.

https://photos.app.goo.gl/CXTFMAoaiLtFeCkj7

I topped it off and went home after dinner and you could hear it hissing out of that spot but since it was all highway at night it didnt get hot enough so it was just air.

New bottle inbound, going to do radiator too because its literally all that is left of this cooling system besides the heater core.