Member
Hello,
here again new problem on my "new 325is".
I Realized the radiator vent is not working. The reason was that it is stuck with a bent blade against the radiator/radiator hose to the coolant reservoir. That was an easy fix because I took a heatgun and I unbent the blade which was stuck. The fan started to spin as soon as I turned on the engine. I do not know since how long this problem was there I Also did the smog test and nobody realized the vent was not working. I did not have any overheating problem, perhaps because right now it's cold and on my commute I Am almost never stop at a traffic light.
The reason why the vent blade bent is that the screw holding the radiator reservoir got broken and all the plastic stuff over there moved back toward the vent and one of the blades got stuck.
Anyway when fixing the vent problem I realized one of the blades (not the one I fixed) is broken/completely missing. So my question is, if it is mandatory to replace the whole vent with a new one or if I can just run with a blade missing. The radiator needs to be dismounted to install a new vent I guess, so I would need a mechanic to do the job.
Member
The mechanical fan of the e36 is the auto world's biggest joke of the 90's.
Delete it! Go all electric. I live in the Phoenix area, and have had only electric for 15+yrs on my 328is convert. I also went with a Zionsville Autosport aluminum radiator and aircraft quality hoses.
118F outside, me doing triple digit MPH, only to sit in traffic for 15-20 minutes later, no problems at all. Since 2001....
Sent from my Nexus 6 using Tapatalk
shade tree mechanic
Moderator
I did not have any problem with my original radiator fan.
Anyway, replace the complete unit against a new one, as a missing blade causes unbalance and can cause more damage to the fan and other parts.
I would also replace the fan clutch at the same time, radiator does not have to come out
E36 Fan & Shroud Procedure
http://www.beisansystems.com/procedu..._procedure.htm
https://www.bimmerforums.com/forum/s...ch-Replacement
Shogun tricks and tips for the E32 series are HERE!
Member
If you decide to keep the stock fan you should replace the fan and its clutch because the clutch is probably bad now because of how it was jammed.
It's not called a "vent", its a clutch fan or radiator fan.
Attn. NEWBIES: Use the search feature, 98% has already been discussed.
Click the search button, select "search single content type", select the "e36 sub forum" specifically, try the "search titles" then try the "search entire posts".
Member
Take a picture of the area. As the motor mounts age, the motor sags down and clearance between the fan blade and the fan shroud is reduced, allowing the fan blade to catch on things.
smokes at gas stations
+1Originally Posted by gdavid
That and the water pump bearings could be old and cause some wobble which allows the fan blades to hit the shroud and break off. The shroud itself is not necessary but it is very helpful at directing the airflow, I would highly recommend keeping it.
License Revoked
I don't think motor mount sag leads to fan blades hitting anything. BMW would have taken that into account. I believe entirely damaged or ruptures motor mounts can do not because the fan sits lower, but because the engine moves violently as you drive over bumps. Tired bumps lead to excess vibration because the rubber is compacted and much harder due to age so no dampening, but no violent movement of the engine over bumps in the same way as rupture mounts.
Anyway op an unbalanced fan will destroy your wp bearings that much quicker and that's a tough job buddy if you've got alot of corrosion on the wp casing to deal with - so put it off for as long as you can by preserving it for as long as you can. Disagree that you need to change the fan clutch though. The viscous fluid there I don't think is affected by an unbalanced fan. If you can get the fan alone change that, change the fan clutch if your current one is bad or due for a change.
Last edited by Thomas525; 02-07-2019 at 07:31 PM.
shade tree mechanic
Moderator
bad motor mounts can cause a lot of damage, I have seen broken ones like this one https://www.eeuroparts.com/blog/3182...ine-mount-diy/
the engine had sagged and moved in the engine bay much more.
How To Tell If Your Engine Mounts Are Bad, Lifting and Banging, Damaging Effects, Vibration at Idle, details.... https://www.eeuroparts.com/blog/2619...ounts-are-bad/
Just found one of my pics motor mount new and old, see the different in height! http://produkte.bilder-speicher.de/1...t-und-neu.html
If the engine drops that much, the fan blades hits the shroud, there is only a small clearance for the fan blades.
Last edited by shogun; 02-07-2019 at 09:48 PM.
Shogun tricks and tips for the E32 series are HERE!
Member
Hi all, and thanks for the advice.
I had the fan and clutch replaced with a new one, $200 total.
Member
replace your motor mounts and trans mounts. Else your fan will blow up again shortly.
Member
you are right it just did blow up again... 5 blades broken and now is totally unbalanced
Member
The mechanic who replaced your fan should have advised you to replace the mounts at the same time.
Member
I'd like to see an electric fan conversion move anywhere near the volume of air an E36 with the Tropical-Cooling fan & clutch can when the temperature is high enough...
The fact that so many of these electric fan conversions involve colder thermostats, high-performance radiators and water-pumps, special coolant additives and so on suggest they're not all they're cracked up to be. Sure, there are plenty of reports of good performance in extreme conditions - but then BMW modified these vehicles appropriately for those sorts of environments.
OP - replace your fan blades. Check to make sure the water-pump and it's pulley don't have excessive play and investigate the engine and transmission mounts. Given the age of our cars, a new fan clutch wouldn't be a bad investment either (I'd also suggest double-checking your auxiliary fan, its relays and the fan switch on the cold side of the radiator).
Member
"Special purpose radiator" means a real aluminum radiator that isn't plastic dictated by the Deutsch Green Party in 1992?
You stick with your plastic toy coolant parts while I don't worry a bit about my real cooling system.
Sent from my Nexus 6 using Tapatalk
Member
There are so many cars out there with plastic cooling system components, both back in the 1990s and today. I'm not saying the components won't fail - they all do at some time or another. I was not making reference to the plastic components (excluding the clutch fan) anyway; I have a metal thermostat housing and water-pump in my vehicle...
Member
I've been in Dallas and now Austin for the last 8 years or so. It's not Phoenix, but it's not Seattle, either.
A good electric fan will keep a car sitting in traffic in 120 ° with the AC on around the 190° mark. It can't quite get it cool enough to cycle the thermostat, but close.
I'm not sure why you'd need any more air than that our need to run any cooler than that.
So I won't argue that the stock fan can move more air - but I can argue that more than that is completely unnecessary.
License Revoked
He's was trying to say that the only thing special about a special purpose radiator, is that it is all made of metal with no plastic parts. No extra cooling capacity/capability, etc.
smokes at gas stations
Yes, this potentially would have saved OP another fan and another round at the service shop. Unfortunately, most shops will only service what is specified by the client so it would be up to OP to request they check the mounts and replace them accordingly if needed.
Member
the mechanic inspected the engine and trans mount. He told they are good and do not need to be changed, given that they look good I suppose they were replaced by previous owners. So he replaced the fan under warranty. The main problem which breaks the radiator fan was not found... I noticed when it happened I was driving with the engine rev at 4500rpm, I mean at higher rpm than usual. Anyway I'm afraid it will happen again. The water pump was replaced 30000mi ago so it should still be good.
Member
Don't assume anything is good by it's age. China floods the market with crap under many different names. Either the water pump is bad or the engine mounts are bad. When you mechanic installs the new stuff, rev the engine with the hood open and observe.
Attn. NEWBIES: Use the search feature, 98% has already been discussed.
Click the search button, select "search single content type", select the "e36 sub forum" specifically, try the "search titles" then try the "search entire posts".
I'm lost
For whatever it's worth, and I don't have the most trained of eyes, but my motor mounts looked fine visually.... Until I decided to replace them anyways and they fell apart.
License Revoked
Mechanics are supposed to use a level to push the engine or the trans mounts slightly and gauge the wobble on the trans mounts, to determine if they need to be replaced. They are also supposed to see how it moves under load to determine that. It is very experiential and that's what they are paid for.
Shogun has said elsewhere that motor mounts can get compressed, not ruptured, and that throws off the driveline's alignment, contributing primarily to excessive vibration untraceable to a specific cause.
You also have Nanie's comments. And finally, there is nothing else that can cause the fan to wobble apart from the wp and motor mounts. If I were you, I would change the mounts first and see, then the wp. Or get a second opinion from another shop. Its a bitch but there's no other options here.
- - - Updated - - -
The reality is that SOMETHING is causing this problem and if that is replaced, and replaced correctly, the problem goes away. A final option would be to remove the fan shroud and drive. Some cooling at idle will be compromised, but not all that much. Driving without the shroud at city speeds is no issue, and the fan is totally not needed when travelling at highway speeds.
Member
Agreed - something is causing this problem. But I wouldn't remove the shroud - that's just hiding your head in the sand.
OP - just pull the motor mounts and inspect them. They're not that hard to get out. I'll be shocked if they're actually in good shape, or if you replace them and have the fan get damaged again. I can't see how the water pump could move that much and NOT be spewing coolant everywhere.
Even if this all makes you go to an electric fan - the problem is still there. I'd be looking at those motor mounts tonight.
-Josh: 1998 S54 E36 M3/4/6 with most of the easy stuff and most of the hard stuff. At least twice. 271k miles. 1994 E32 740il with nothing but some MPars. 93k miles.
Member
I think I got were the problem is. The clips holding the little radiator hose (the one which connects the radiator reservoir to the radiator itself and goes from left to right looking at the radiator from the front) are broken. The hose is a little bit saggy. The fan can easily suck the hose against itself so that the blades will hit the hose. The previous fan was broken and one blade was stuck under the hose itself. The hose was not broken because it is very elastic. But I think this could be an explanation. Trying to fix this I used a few zip tie to hold the hose in place without sagging. In particular I used two small zip tie on the right side after pulling the hose a little bit so that it won't sag anymore. My concern now is about the hose cross section which is slightly reduced as you can see in the picture. My concern rises because since I applied this "hand made" fix I notice a small leak of coolant fluid from the coolant reservoir cap which was not happening before.
Member
I tightened the radiator reservoir cap more and I had no leaks this time.
Posting Permissions
Reply With Quote
Bookmarks