View Full Version : How difficult is it to replace an engine thermostat?
On my 35-45 minute commute the last few days my engine temp gauge has been barely rising off of the cold peg. Normally it points straight up after the engine gets warm. This is leading me to suspect that the thermostat is stuck open.
Does my suspicion sound correct? And how difficult is this to do?
BahnBaum
12-08-2005, 01:31 PM
http://www.pelicanparts.com/bmw/techarticles/E36-Thermostat/E36-Thermostat.htm
Alex
On my 35-45 minute commute the last few days my engine temp gauge has been barely rising off of the cold peg. Normally it points straight up after the engine gets warm. This is leading me to suspect that the thermostat is stuck open.
Does my suspicion sound correct? And how difficult is this to do?
Your suspicion sounds dead on. It is not tremendously difficult; I've never done it before, but have seen DIYs floating around when I was looking in to the issue for my old 323. You can probably find those over at bimmerforums, if nowhere else.
The thing is, while you're at it, you definitely should replace the water pump, and given the failure propensity for E36 radiators at 80-100K miles, you should probably put in a new radiator and hoses, as well.
BahnBaum
12-08-2005, 01:35 PM
Your suspicion sounds dead on. It is not tremendously difficult; I've never done it before, but have seen DIYs floating around when I was looking in to the issue for my old 323. You can probably find those over at bimmerforums, if nowhere else.
The thing is, while you're at it, you definitely should replace the water pump, and given the failure propensity for E36 radiators at 80-100K miles, you should probably put in a new radiator and hoses, as well.
http://www.pelicanparts.com/BMW/techarticles/E36-Water-Pump/E36-water-pump.htm
http://www.pelicanparts.com/bmw/techarticles/E36-Radiator-Replacement/E36-Radiator-Replacement.htm
Alex
Every thermostat replacement I've done, has been very simple. Now, assuming that BMW didn't hide the thermostat housing somewhere that's impossible reach without disassembling the entire engine bay, you should have no trouble at all.
John V
12-08-2005, 01:41 PM
I've done water pump / thermostat / radiator / belts / hoses on an E36. It's not difficult, but there are some frustrating aspects to the job. TD, if you want to DIY I'd be more than happy to lend a hand.
JV
Your suspicion sounds dead on. It is not tremendously difficult; I've never done it before, but have seen DIYs floating around when I was looking in to the issue for my old 323. You can probably find those over at bimmerforums, if nowhere else.
The thing is, while you're at it, you definitely should replace the water pump, and given the failure propensity for E36 radiators at 80-100K miles, you should probably put in a new radiator and hoses, as well.
Well, I'm up to ~78K miles. So I need to consider this.
If only it weren't so damn cold that the idea of spending a day in the garage doing this sounds painful.
I've done water pump / thermostat / radiator / belts / hoses on an E36. It's not difficult, but there are some frustrating aspects to the job. TD, if you want to DIY I'd be more than happy to lend a hand.
JV
Thanks!
How urgent is this repair (the thermostat not the other things)?
http://www.pelicanparts.com/bmw/techarticles/E36-Thermostat/E36-Thermostat.htm
Alex
They didn't mention anything about refilling the cooling system after replacing the thermostat. I wonder how many armchair mechanics have neglected that step.
Thanks!
How urgent is this repair (the thermostat not the other things)?
As long as the thermostat isn't stuck closed, then I would think you'd be OK. But I'm no mechanic, so take someone else's word for this.
John V
12-08-2005, 01:47 PM
78k on the original radiator?!
If I were you, I'd buy one like.. REAL SOON.
Overcooling isn't such a huge deal, but it's not gonna help your gas mileage any.
My '65 Landcruiser used to eat thermostats...
I probably had to have them replaced about twice a year... Probably should haved learned to DIY it...
I've checked out the links but I want to peruse the Bentley manual before deciding to take this on.
And I also broke and dislocated the pinky on my right hand recently. It's still far from 100%. In fact, right now the idea of turning a wrench requiring force is painful.
Thermostat replacement is relatively simple, as is radiator replacement. Be prepared for a little bit of coolant splashing around (more if you do the radiator one day).
John V
12-08-2005, 02:27 PM
I've checked out the links but I want to peruse the Bentley manual before deciding to take this on.
And I also broke and dislocated the pinky on my right hand recently. It's still far from 100%. In fact, right now the idea of turning a wrench requiring force is painful.
The bentley, IMO, is just about useless. One of the more terrible shop manuals I've ever had the pleasure of using.
It's really only good for torque values.
BahnBaum
12-08-2005, 02:31 PM
The bentley, IMO, is just about useless. One of the more terrible shop manuals I've ever had the pleasure of using.
It's really only good for torque values.
It was fine for my e30.
Alex
John V
12-08-2005, 02:47 PM
It was fine for my e30.
Alex
Ugh, the E36 one is just terrible. There aren't any decent pictures in the thing, some procedures are just flat out WRONG (i.e., can't get there from here) and it skips steps seemingly at random.
OTOH, Mazda knows how to write a factory service manual. The one for my RX-7 had pictures for literally every step (including full engine overhaul and transmission overhaul).
Jason C
12-08-2005, 02:56 PM
I still have some access to centernet/webTIS. Let me know what exactly are you doing or might end up doing and I'll see if I can pull the repair instructions (includes AZD in NM and anything else that's a related task).
BMW cooling systems always seem to be a weak point, so radiator + water pump + thermostat is probably a good idea.
Contrary to what someone said earier, overcooling is a big deal. It's not as immediate of an issue as undercooling of course. It depends on how long it goes on. For a brief amount of time, you should be able to get away with it. But if you let it slide for a while, your constant rich condition (as the engine never warms up) can and probably will end up damaging/destroying the catalytic converter. Not something which I'd like to replace. Probably a lot of money.
John V
12-08-2005, 03:00 PM
I still have some access to centernet/webTIS. Let me know what exactly are you doing or might end up doing and I'll see if I can pull the repair instructions (includes AZD in NM and anything else that's a related task).
BMW cooling systems always seem to be a weak point, so radiator + water pump + thermostat is probably a good idea.
Contrary to what someone said earier, overcooling is a big deal. It's not as immediate of an issue as undercooling of course. It depends on how long it goes on. For a brief amount of time, you should be able to get away with it. But if you let it slide for a while, your constant rich condition (as the engine never warms up) can and probably will end up damaging/destroying the catalytic converter. Not something which I'd like to replace. Probably a lot of money.
As I've already posted, I'm willing to help / do in entirety the work that needs to be done. Don't need a manual, don't need repair instructions, don't need pelican's DIY. It's not hard. Just need the torques for the thermostat cover.
The cats can tolerate a few weeks of driving with an overcooling condition. The cars don't run THAT rich when they're cold.
JV
Jason C
12-08-2005, 03:05 PM
The cats can tolerate a few weeks of driving with an overcooling condition. The cars don't run THAT rich when they're cold.
I was mostly replying to the notion that it wasn't a big deal. That is the kind of thinking that can lead people to remove their thermostats from their vehicles.
A thermostat that is removed/stuck open can actually lead to an overheat condition, as the coolant circulates too fast and does not have enough time to pick up the heat from the engine. This is not as common as the symptoms that was described by TD, usually what happens is permanent open-loop operation/shit for gas mileage, with the cat loading up over time.
John V
12-08-2005, 03:16 PM
I was mostly replying to the notion that it wasn't a big deal. That is the kind of thinking that can lead people to remove their thermostats from their vehicles.
A thermostat that is removed/stuck open can actually lead to an overheat condition, as the coolant circulates too fast and does not have enough time to pick up the heat from the engine. This is not as common as the symptoms that was described by TD, usually what happens is permanent open-loop operation/shit for gas mileage, with the cat loading up over time.
Yeah, sure, bad things will happen with no thermostat.
IMO, if someone is dumb enough to read this and remove their thermostat, they deserve whatever destruction they experience. ;)
Ugh, the E36 one is just terrible. There aren't any decent pictures in the thing, some procedures are just flat out WRONG (i.e., can't get there from here) and it skips steps seemingly at random.
OTOH, Mazda knows how to write a factory service manual. The one for my RX-7 had pictures for literally every step (including full engine overhaul and transmission overhaul).
That's because Mazda knew it would be the most used accessory for that car.
John V
12-08-2005, 03:24 PM
That's because Mazda knew it would be the most used accessory for that car.
You don't know the half of it. There were things wrong with my RX-7 that people flat out told me could not cause the problems I was having. Well - the car never ceased to amaze me.
On that subject, if you're up for a laugh, go to google and type "John Vitamvas" (with the quotes) into the search box. Then hit the "I'm feeling lucky" button.
Nick M3
12-08-2005, 03:27 PM
You know, Tom, if you buy parts real fast, we could probably do it in Terry's garage...
You don't know the half of it. There were things wrong with my RX-7 that people flat out told me could not cause the problems I was having. Well - the car never ceased to amaze me.
On that subject, if you're up for a laugh, go to google and type "John Vitamvas" (with the quotes) into the search box. Then hit the "I'm feeling lucky" button.
That wasn't Neal Patrick Harris, was it?
John V
12-08-2005, 03:37 PM
That wasn't Neal Patrick Harris, was it?
:lol:
Great. Now the "Doogie Howser" theme song is stuck in my head.
clyde
12-08-2005, 04:01 PM
As I've already posted, I'm willing to help / do in entirety the work that needs to be done.
As I've learned, if he's there, it's best to just let him hack away at it on his own. He won't give you any room to get in and do anything yourself anyway. Just don't let him near the parking brake when the calipers are off. :eek:
As I've learned, if he's there, it's best to just let him hack away at it on his own. He won't give you any room to get in and do anything yourself anyway. Just don't let him near the parking brake when the calipers are off. :eek:
I'm confused. Are you talking about me?
clyde
12-08-2005, 04:08 PM
I'm confused. Are you talking about me?
in my best Dom DeLuise in "Cannonball Run"...
him
in my best Dom DeLuise in "Cannonball Run"...
him
Ah....
Whew!
I was momentarily afraid that I was forgetting some DIY session mishap I was involved in.
BahnBaum
12-08-2005, 04:16 PM
You know, Tom, if you buy parts real fast, we could probably do it in Terry's garage...
I was thinking the same thing.
Alex
clyde
12-08-2005, 04:29 PM
Ah....
Whew!
I was momentarily afraid that I was forgetting some DIY session mishap I was involved in.
No, I'd just keep you away from the drill if my car was there. :eeps:
rumatt
12-08-2005, 05:13 PM
On that subject, if you're up for a laugh, go to google and type "John Vitamvas" (with the quotes) into the search box. Then hit the "I'm feeling lucky" button.
:lol: :lol: :lol:
UPDATE-
I paid very close attention to the temp gauge on the way home tonight and now I don't know what to think.
If you all recall, the temp gauge is round with the range of the needle being from about 10 o'clock to about 2 o'clock (9:30 to 2:30 maybe). During normal operation when the engine is warm, the needle points straight up (noon).
When I started the car, it was full cold. But within 3 or 4 minutes, the needle had moved ever so slightly. By 10 minutes into the drive it was up to around 10:30 -11 o'clock. Then it dropped a bit before bouncing back up and dropping again.
By the time I was near my parents' house near Olney (30 or so minutes into the drive) it was at about 11:30. About 2 hrs later when I went to leave, of course it was pegged cold again. But within the 20 minute drive home, it got to full noon.
I swear it barely moved off the peg the last few commutes, 40 - 50 minutes in one shot.
The up and downs tonight seem odd but the fact that it did warm up fully makes me wonder if there was something possibly frozen shut (or open) and it finally "melted" itself free.
Or am I losing my mind?
BahnBaum
12-08-2005, 10:22 PM
Or it could be the sending unit.
But really, with the miles and age of he car, the radiator, water pump and thermostat are PM items. I'd just do it.
Alex
rumatt
12-08-2005, 10:23 PM
If all these parts are old, and are generally considered wear items, just replace them all asap anyway maybe? :dunno:
I agree that I need to replace them all.
But at least I now think I can wait until it warms up a few degrees.
I was looking at finding time in the next couple of weeks to do it (including paying rush shipping to have parts this weekend) and now I don't quite have to rush things THAT much.
It's always weird when a problem seems to just "go away". You know it won't last, but you can sometimes appreciate the reprieve.
Pushing this out past the holidays would do a lot for my sanity.
Nick M3
12-08-2005, 11:07 PM
I agree that I need to replace them all.
But at least I now think I can wait until it warms up a few degrees.
I was looking at finding time in the next couple of weeks to do it (including paying rush shipping to have parts this weekend) and now I don't quite have to rush things THAT much.
It's always weird when a problem seems to just "go away". You know it won't last, but you can sometimes appreciate the reprieve.
Pushing this out past the holidays would do a lot for my sanity.
Yeah, but Terry's garage is heated. :p
BahnBaum
12-08-2005, 11:10 PM
And tunes. And a refrigerator. And internet access.
Alex
clyde
12-09-2005, 09:13 AM
and tools
and people that think they know what they're doing ;)
and ~75 miles away
Well, I need a parts list to order.
I know I'm getting a thermostat, water pump and radiator. With the thermostat there is an associated, o-rings, gasket and housing. Do these need replaced as well? And with the radiator, there is a slew of related parts (hoses, cap, etc, etc).
What of these related parts generally should be replaced at the same time?
This is the question that pretty much stopped me from placing an order online yesterday. I had a cart started at bimmerparts.com.
And despite what John says, I'm getting the Bentley out.
John V
12-09-2005, 09:37 AM
Well, I need a parts list to order.
I know I'm getting a thermostat, water pump and radiator. With the thermostat there is an associated, o-rings, gasket and housing. Do these need replaced as well? And with the radiator, there is a slew of related parts (hoses, cap, etc, etc).
What of these related parts generally should be replaced at the same time?
This is the question that pretty much stopped me from placing an order online yesterday. I had a cart started at bimmerparts.com.
And despite what John says, I'm getting the Bentley out.
As long as you're in there, you might as well do a water pump. It's only another couple mintues while you've got the shroud off, the fan off, etc. DO NOT DO NOT DO NOT get an aftermarket "metal" impeller water pump. Go to the dealer and get yourself one of their newer "composite" impeller pumps. Bill at BMW of Towson will know exactly what you need. The aftermarket metal ones are crap - the PO of my car had one put in and it was weeping past the bushing after only 20 thousand miles.
The new pump will come with an o-ring. The thermostat I think comes with the o-ring it needs, but not sure. Honestly, it's easiest to hit up the dealer for this stuff, because a good parts guy will make sure you get everything you need. If you have the metal thermostat housing, you need the gasket for it. Not sure about the plastic ones.
The hoses generally last a long time, and can easily be replaced at a later date. Don't forget to pick up a gallon or two of BMW coolant while you're at it.
John
BahnBaum
12-09-2005, 09:38 AM
As long as you're in there, you might as well do a water pump. It's only another couple mintues while you've got the shroud off, the fan off, etc. DO NOT DO NOT DO NOT get an aftermarket "metal" impeller water pump. Go to the dealer and get yourself one of their newer "composite" impeller pumps. Bill at BMW of Towson will know exactly what you need. The aftermarket metal ones are crap - the PO of my car had one put in and it was weeping past the bushing after only 20 thousand miles.
The new pump will come with an o-ring. The thermostat I think comes with the o-ring it needs, but not sure. Honestly, it's easiest to hit up the dealer for this stuff, because a good parts guy will make sure you get everything you need. If you have the metal thermostat housing, you need the gasket for it. Not sure about the plastic ones.
The hoses generally last a long time, and can easily be replaced at a later date. Don't forget to pick up a gallon or two of BMW coolant while you're at it.
John
And with your CCA membership, you can get 20% off at Towson, which gets the prices in line with, or better than, many i-net sources.
Alex
Since I'm "working form home" today, I'll head down to VOB (ugh!) later today and get what I need. Towson is pretty far from me and not really even on the way for this weekend. And the VOB parts counter guys have always actually been very helpful to me. Knowledgable and pro-DIY.
But as I said before, I'd be up on Sunday (not tomorrow). Tomorrow night is our company Xmas party and it's in Baltimore. The back and forths plus the time I'd need to clean up would make it just too tight time-wise. Plus, I've got a lot to do around the house as the kids have started decorating the house themselves and the place is a disaster.
How early Sunday morning?
And with your CCA membership, you can get 20% off at Towson, which gets the prices in line with, or better than, many i-net sources.
Alex
I don't think it's 20%, but VOB does give a CCA discount. I think it's 15%.
It's worth 5% to me to not have to trek up to Towson.
clyde
12-09-2005, 10:12 AM
If you're going to go to Terry's tomorrow, Towson isn't really out of the way (if Bill can leave a package/price for pickup on Saturday). Or...you could try to sweet talk Bren into picking the stuff up for you and pay by CC over the phone.
Bill is the one good thing about an otherwise mediocre Towson, IMO. We all know about VOB.
edit- missed the saturday/sunday part...get to work on bren
If you're going to go to Terry's tomorrow, Towson isn't really out of the way (if Bill can leave a package/price for pickup on Saturday). Or...you could try to sweet talk Bren into picking the stuff up for you and pay by CC over the phone.
Bill is the one good thing about an otherwise mediocre Towson, IMO. We all know about VOB.
edit- missed the saturday/sunday part...get to work on bren
I actually need a couple other things as well.
I'll suck it up and go to VOB.
I don't mind stopping at Towson if you need me to...it's only a few minutes from me and I'll drive right by there on the way to Terry's.
When it comes to hoses, I have an "as-long-as-you're-in-there" mentality. You might as well replace them, since it's not every day that you will want to have coolant dripping all over the place. And as long as the radiator's out, I agree wholeheartedly with the water pump.
(Then again, "as long as you're in there" caused my wallet a lot of heartache a couple of years ago)
When it comes to hoses, I have an "as-long-as-you're-in-there" mentality. You might as well replace them, since it's not every day that you will want to have coolant dripping all over the place. And as long as the radiator's out, I agree wholeheartedly with the water pump.
(Then again, "as long as you're in there" caused my wallet a lot of heartache a couple of years ago)
Hey, as long as you are in there:
http://cgi.ebay.com/ebaymotors/2004-Z06-Engine-LS6-Not-LS1-LS2_W0QQcmdZViewItemQQcategoryZ33615QQitemZ8020308 337QQrdZ1
http://i6.ebayimg.com/01/i/04/e1/6d/de_1_b.JPG
That would definitely *perk* things up a bit.
:yikes:
clyde
12-09-2005, 11:28 AM
too bad Fair doesn't post here anymore. He bought that RX-8 and disppeared...
rumatt
12-09-2005, 01:19 PM
Hey, as long as you are in there:
:lol:
rumatt
12-09-2005, 01:19 PM
Zach's going to be stuck in the snow somewhere between Boston and NY anyway. We'll have all day to work on TD's car.
Zach's going to be stuck in the snow somewhere between Boston and NY anyway. We'll have all day to work on TD's car.
Funny. :ack:
Zach's going to be stuck in the snow somewhere between Boston and NY anyway. We'll have all day to work on TD's car.
As of right now, I'm stuck in the snow in Boston. We have about 6 inches of snow/slush on the ground and it's raining/snowing sideways. The Mass Pike is at 10mph according the radio. I'm not going anywhere for a while. :(
rumatt
12-09-2005, 03:07 PM
As of right now, I'm stuck in the snow in Boston. We have about 6 inches of snow/slush on the ground and it's raining/snowing sideways. The Mass Pike is at 10mph according the radio. I'm not going anywhere for a while. :(
Oops. I wouldn't have said it if I thought it would be true. : oops:
Just chill out for a few hours. You'll be good to go. It stop snowing in NY hours ago.
I'll still come up on Sunday to help, but I don't think we need to do my car right now.
I took it out today and the temp registered normal. The Bentley manual has a short section in the cooling system section called "Thermostat Quick Check" where it says to check the upper radiator hose when the car is warm. If the hose is hot to the touch, everything is fine. Well, it's hot to the touch.
I KNOW I need to replace this stuff pretty soon. But, as I said earlier in the thread, if I can puch this out past the holidays, it will do a lot for my sanity.
I'm pretty sure that one of you guys will have the itch to mod something in the near future, producing another excuse to head to Terry's.
The other thing is that the radiator (to pick just one part) lists for $400. VOB offers a 10% CCA discount ($360). Towson a 20% discount ($320). But bimmerparts has the OE radiator for under $200.
I'll still come up on Sunday to help, but I don't think we need to do my car right now.
Cool. :)
I'll still come up on Sunday to help, but I don't think we need to do my car right now.
I took it out today and the temp registered normal. The Bentley manual has a short section in the cooling system section called "Thermostat Quick Check" where it says to check the upper radiator hose when the car is warm. If the hose is hot to the touch, everything is fine. Well, it's hot to the touch.
I KNOW I need to replace this stuff pretty soon. But, as I said earlier in the thread, if I can puch this out past the holidays, it will do a lot for my sanity.
I'm pretty sure that one of you guys will have the itch to mod something in the near future, producing another excuse to head to Terry's.
The other thing is that the radiator (to pick just one part) lists for $400. VOB offers a 10% CCA discount ($360). Towson a 20% discount ($320). But bimmerparts has the OE radiator for under $200.
All good points. Perhaps you should print this post out so that you can review it while you are waiting for the AAA guy when your radiator packs it in next week...
j/k, but at 80K miles on that radiator, you are living on borrowed time. I'd keep a close (like, daily) eye on the hose coupling between the upper hose and the radiator. If there is ANY sign of leakage, I'd take the Saab.
John V
12-09-2005, 09:16 PM
All good points. Perhaps you should print this post out so that you can review it while you are waiting for the AAA guy when your radiator packs it in next week...
j/k, but at 80K miles on that radiator, you are living on borrowed time. I'd keep a close (like, daily) eye on the hose coupling between the upper hose and the radiator. If there is ANY sign of leakage, I'd take the Saab.
Bimmerworld still has E36 radiators for $184 last I checked.
JV
More or less since I last posted to this thread, the temp gauge has went all the way up to the ideal normal (noon) position on every drive over ~20 minutes.
I know problems don't "go away", but can I now consider this problem no more urgent that before I noticed anything wrong?
The HACK
01-04-2006, 03:37 PM
I know problems don't "go away", but can I now consider this problem no more urgent that before I noticed anything wrong?
No.
The thermostat determines if your engine gets coolant from the reservoir and the radiator. Do you really want to have that thing fail while you're on a long commute or even on the way to work?
Get it replaced while it's still working. This is one instance where "if it ain't broke" don't apply. Those thermostats should actually be replaced as a preventative measure, like every 60K miles.
lip277
01-04-2006, 04:01 PM
thermostats should actually be replaced as a preventative measure, like every 60K miles.
Absolutely.
I'm kicking myself that I didn't change the TS in the Yukon when I had the coolant changed at 100,000 miles. I probably should have done both the TS and water pump as a preventative measure.
Oh well. Maybe in my free time over the summer.
Yeah - Right....
vBulletin® v3.7.1, Copyright ©2000-2024, Jelsoft Enterprises Ltd.