[this_is_dakota]

What’s up everyone, new kid here, take it easy on me lol. Anyway i own a 2006 325i, and a few weeks ago I started hearing a terrible knocking sound coming from engine bay. Found it to be my ac compressor pulley was starting to go. Order a new compressor, and was debating on doing the job myself or dishing out 200-600 dollars (or whatever) to have it replaced. Finally decided to tackle the job my self...

But before I even decided to do the compressor, I wanted to replace the tensioner and idle pulleys. I had the fan pulled out to replace the tensioner pulley first, and while I was trying to place the coolant hose that sits on top of the radiator (with the plastic line) in an area out of the way, the plastic line just snapped in half (thanks bimmer engineers). Went to auto zone and picked up a 20 inch 5/16 metal brake line, cut to length and refitted. Back on track right? Nope. As I went to drop the fan back in I accidentally hit the nipple that connects the plastic line coolant hose to the upper radiator hose. Plastic nipple just snapped right off..

Well, cool. Now I get to drop 23 bucks for an upper radiator hose. Went to autozone, picked it up, also stopped by the dealership to snag a set of compressor bolts since they’re one time use. Started to try to remove the upper radiator hose from the radiator, and guess what?? Snapped the plastic connector on the radiator. So now here i am, about to head back to autozone to buy a new radiator. Fantastic, I’ve come to hate plastic.

As much as this whole situation sucks, I have learned quite a bit from these mistakes. Mostly being f***ing careful. And patient. Sorry for such a long winded first post, I had to vent (cooling system pun intended).

Does anyone have any advice on getting these incredibly stubborn hoses off? Still need to remove lower hose and I’m a little timid as you might guess lol.

[Dan Bilzerian]

Carefully.
/thread

[CTinline-six]

Before BMWs I worked on Jeeps and trucks, which are usually all metal and pretty heavy duty. In New England lots of things rust together and require a decent amount of force to get apart.

I work in IT, and I relate BMWs to working on computer hardware. A lot of it is fragile plastic, and you just have to pry on things carefully and take your time. After a few years the plastic bits get brittle and are more likely to break, especially with all the heating and cooling cycles. Using the right tools also makes a world of difference. I have a bunch of tiny picks and pliers that work well for plastic connectors and hoses.

[this_is_dakota]

Would heating the hose up a bit with a heat gun help loosen it? Obviously using heat in extreme moderation. Not sure about this method since they are the quick connect hose ends?

[this_is_dakota]

Also I’ve read that leaving the system without coolant for an extended period of time could damage the water pump. It’s been about 8 hours since i drained the coolant, but i haven’t disconnected the hose from the pump to the block to drain that area yet. Had to wait for my gf to get off work with the other vehicle to pick up the radiator.

[Efthreeoh]

Okay, I'm impressed with refitting the vent return line with brake line; I've been contemplating the same fix, but BMW redesigned the vent return line and hopefully used better materials, which I installed on my car. Rather than go into specifics, attached is my DIY I posted several years ago on refurbing the entire cooling system, all 9 hoses. It discusses each hose in detail on how to remove and replace.

My advice is don't buy parts from Auto Zone. Try to buy BMW parts on line or at least the original equipment manufacturer aftermarket versions. BMW loves to make complex parts, and non-OEM manufacturers some times have difficulty building parts to BMW spec.

When I did my hoses, I had to cut the old upper and lower hoses off the radiator, then remove the radiator, secure it down to my (wooden) work bench and pry off the old hose connectors off the hose bibs. If I were you, I'd just get a new lower radiator hose and temperature sensor. The old temperature sensor will most likely leak if you try to use it in the new hose. If you want to save the old lower hose and not replace it, then remove it from the water pump side, then pull the radiator out, then try to pry the lower hose off. The stupid BMW hose connectors do not allow you to twist the hose to break the tension between the connector and hose bib, like you normally wood on a normally engineered automobile... You can only wiggle the hose connector up and down and left and right to try and break the tension.

Why BMW just can't use f'ng hose clamps is beyond my understanding.

Anyway good luck with it.

[NGEE]

Recently replaced the upper rad hose on my son's 99 328is. Three nights later he's stuck on the side of the road - the plastic nipple had disintegrated under the torque of the hose clamp. Lesson learned - if you have to replace a cooling system component, go all-in and replace all that plastic shit.

[this_is_dakota]

I was able to get the lower hose of the radiator today to replace the radiator. Woke up this morning and I’m incredibly stiff and sore from using all my strength on those hoses lol. Also had a hell of a time refitting the upper hose to the oil filter housing. Took like 45 minutes of struggling to push it in. Did the ole lube and rubber mallet technique, got it in.

Anyway, did the vent procedure and seems I️ have leak at the lower hose, radiator side connection. Thinking old o ring, sensor o ring. Gonna try to get to it tomorrow. Might have to replace the hose itself, but I need my car for work purposeswhich why I’ve been resorting to autozone. I’m planning on overhauling the system when i have a week off for Christmas.

Meanwhile, after all this I still have to tackle the compressor job. Go figure.

[Needbmwpartzz]

Sometimes DIY's go horribly wrong....but you sir are on the right track.....be more careful to understand the systems you are messing with first and read-up here and other places I online to learn from others mistakes as well.
GL OP

[MysticRob]

Originally Posted by NGEE

Recently replaced the upper rad hose on my son's 99 328is. Three nights later he's stuck on the side of the road - the plastic nipple had disintegrated under the torque of the hose clamp. Lesson learned - if you have to replace a cooling system component, go all-in and replace all that plastic shit.

LOL, sounds familiar. I had a leak coming from the often-leaky coolant crossover line secured to the top of the radiator core support. Went to dealer for new part, and during install I discovered that same upper-hose nipple was so brittle it just broke right off. Very corroded. Had to return to dealership for that part too.

[The_E92_Fan]

During inlet install, i broke off the vertical nipple for coolant return to the tank. The best option i determined was to tap into the same hole and make it bigger. I installed a stubby brass connector and epoxied it in. Cheap, easy, and a stronger connection. If anyone wants a visual or an idea on how to do it right the first time, don't hesitate to contact me. 5 minutes of my time can save you time, money, and a headache.

[this_is_dakota]

As far as the compressor goes my shop evac the system for free, and so I went ahead and did that job. I had bought a new “used” compressor from my buddy’s car he had totaled. Had his replaced a month ago at dealer. Anyway, the actual compressor was still working on my car (air blowing cold as tits) it was the pulley bearing that was failing. Initially I thought I’d just swap the whole pulley wheel assembly. Then opted for the full comp swap. Finished it today, wasn’t too bad, I was able to do it all from the top of the car except removing the bolts for the thermostat. I will say getting the old one out/new one in was a nightmare along with trying to reinstall all three bolts. I have smaller hands this stuff works out a lot, but there was just so little space to work with.

Anyway question, since the new used compressor had oil in it already, do i need to add any still? The guy at the shop didn’t really do a vaccume of the system, just hooked his gauges to the low side and i guess syphoned it into an antifreeze bottle filled with water lol.