Hey guys, you may have seen my previous post about picking up an 05 R53 for $600. I haven’t gotten a chance to get under it or run the engine yet to really look at things yet, but it looks like it’s gonna need a head gasket and a few other gaskets to start with. The previous owner put K-Seal head gasket repair in the coolant so I want to flush all that crap out of the system. What’s the best process to do this? I understand that there’s no coolant drain plug so I have to disconnect the lower hose I believe? Flush with water, then run engine with clean coolant, then drain coolant and replace with clean coolant again?

 

Yes, yes and yes. You are spot on.

Be careful not to mix red and blue coolant. Those can react to eachother. Blue is the right stuff although I cannot remember if it was g11 of g12 stuff

 

I'd suggest flushing, filling with distilled water, and running it, then repeating until everything runs clear. No need to waste coolant and then flushing it out. Some people use a shop vac to pull coolant out, but I've never tried it.

 

Prestone radiator flush is cheap and very effective. Drain your coolant, add Prestone and distilled water and run it for 15 minutes. Drain and fill with coolant -- you're done. Green coolant works as well as blue, just don't mix them as noted above. You might also want to change your thermostat while you're at it.

 

Follow above 100%. Seeing as your doing a head gasket though I'd suggest the drain, fill with water, drain and repeat 3x or more. It know it's a pain but if you ultimately want to flush out the block and all i recommended this.

Once your doing the head gasket, the rad will be completely off. Flush this out with your garden hose, in for a penny in for a pound concept change the thermostat + upgrade to aluminum housing (rockauto cheap).

If you disassemble this far your only remaining coolant is in the lines towards the firewall behind the thermostat. Which are oil cooler + lines, cabin heater core + lines, and inside the bottom of the engine block.

Popping the lines off oil cooler is possible from above or right wheel well. Removing the lines off the cabin heater core is done inside the car under the drivers dash. This is depending how deep you want to dive.

In your situation I would do all the above besides the cabin heater core. If you flush the engine over and over with water, the little amount remaning in only the heater core shouldn't affect anything. It's not a complicated cooling system once your in there! Best of luck

 

Second note, inspect the timing chain, and camshaft.

My engine 175k KM (108 miles) had significant wear to the timing chain guides, the chain itself was perfect. The guides are cheap, especially once removed anyway.

The camshaft has known pitting, as my recent post. If yours has excessive wear replace it, inspect your rocker rollers and replace if needed.

A couple simple things to save a headache down the road, also highly suggest to follow along with ModMini on YouTube when doing this sort of work. Guys a legend!

 

It helped me, Thank you so much for the help.

 

It like a good plan! Flush thoroughly, replace gaskets afterward.


 

Glad to have helped you! Been a long time lurker myself but after doing what seems like weekly rebuilds on my R53 since owing decided to step up.

Simple cars in reality but a pain in the A@#

 

Thanks! It currently has the green “universal” coolant in it. Should I just keep with that for now? My R50 also is using the green universal stuff (I bought the car that way) and it doesn’t seem to be causing any problems

 

Yeah thanks for all the helpful info so far!

 

Just now seeing this post lol. I’ve had a lot to read on my other thread haha. Great info and advice! Thanks so much!

 

Coolant is a sticky situation for me. When I purchased my car it was the same scenario, generic Prestone coolant. Did a bunch of work, including brand new bmw water pump... months later leaking from the water pump weep hole. Did an entire investigation of everything, replaced a few things like thermostat and housing Yada Yada... went through another 2x pumps.

Then decided to look into mini safe coolant, long story short and tons of forums later. Zerex G05.

Apparently some other brands of coolant have ingredients prone to eating seals and gaskets like phosphate. A little googling should back this up further!

 

Man that sounds like a pain, changing water pumps tends to be annoying.

Ahh so Zerex G05 is what the Mini’s take? I actually already have some of that because that’s what my Dodge Durango takes haha.

 

Yesir, considering i bought mine for a steal like you and instantly doubled the value in water pumps lol. Some reading here. Can quote i have used G-48 without issue also.

https://www.northamericanmotoring.co...-to-use-4.html

 

Awesome, thanks for saving me from the coolant rabbit hole lol. I wonder if it uses the same type because it’s a Chrysler designed engine

 

@Stormrider84 makes sure you flush EVERYTHING at this point. Even leaving the heater core with different coolant can cause "gelling" of the coolant.