New owner of '90 535i - some questions about this car

[aaron]

Hi folks,

I just bought a 1990 535i, 128k miles, auto trans. I have several questions that perhaps some of you could help me with.

I didn't buy this car for relaibility - mostly I bought it because I want (need!) RWD and refuse to buy the trash detroit sells. I plan on it being tempermental, and that's OK. I've been looking for a 535 for a while, and I really like the layout of the straight big six motor. I plan to perform all regular maintenance, and have done all the work on my japanese cars. But this is my first german car.

Items I've seen come up over the past two days are:

There is a groaning sound coming from the rear of the car when turning at low speeds. It only occurs when turning, never going straight. I'd assume wheel bearings, except it happens equally when turning either direction. It almost feels like something is grabbing / tugging back there. Is there something else in the suspension? A trailing arm bushing perhaps - that would cause the tires to fight against each other? The tires are spankin' bran new, so I can't tell if there will be any wear patterns yet.

It seems to be leaking coolant from the upper radiator hose where it meets the radiator. It has a screw type clamp on it. Is that correct, or should it have a spring clamp? It's rather tight, and I don't want to break the radiator by clamping down on it too hard. The hose seems fine, as does the radiator. It just leaks. My fear is a leaking head gasket causing excessive pressure build up, but my local european auto mechanic disagrees (after an over the phone diagnosis). Ambient temperature yesterday was 98 degrees. The needle stays less than a hair's width above the 1/2 mark on the gauge. After shutting off while hot and restarting 20 minutes later, the needle sprung up to the 3/4 mark, but fell back down to 1/2 after driving for a few minutes. I imagine the sensor was just sitting in a hot spot and went back to 1/2 after the coolant started flowing. I don't know any repair history, and I know this car is prone to overheating. Shall I just replace the clamp? Flush the system for good measure? Or be paranoid and start replacing parts for fun?

And: I can't check the transmission fluid. It doesn't have a dipstick (or so it seems to me). Am I !? There is just a cap on the tube where the dipstick would go, and I can't remove it. Was this a no-tamper device for the US market to drive more customers to the service dept?!

And: Should I pay $50 to have the oil changed by the dealer so they can reset that service interval thinger? Or should I do it myself? The manual doesn't specify oil change intervals, so I'm thinking it's doing some kind of algorythm to determine, by its self, when it wants new oil. Maybe an hours of operation combined with number of revolutions, or something? I like to honor that, if that's what it's doing. But if I can't reset the service indicator, then I'd have to just start doing it based on milage.

And: The owners manual says that 10-40 oil should be used between 20 degrees and 70 degrees. 10-50 oil lets it go up to 80 degrees. But here in Utah we're routinely around 100 degrees. That would call for 15-50! That seems absurdly thick! I know this motor was used by BMW for decades, and it's probably an older design - but should I really put 15-50 oil in it?!

Finally: If I put the transmission into manual shift mode, it does it every time. If I attempt to put it back to automatic, it does it about 1/2 the time. I have to keep driving and fiddling with it, and eventually it switches back. Is that a problem with the switch, or with the transmission?

Thanks for listing to all my questions! I want to take good care of this car that really appears to be in excellent shape for its age at this point.

Aaron

[crashnburn80]

For your oil service it is very easy to do yourself, including resetting the service lights. You can find instructions on brunos website www.bmwe34.net, specificly: http://www.bmwe34.net/e34main/mainte...il_service.htm.

As for your leaking upper radiator hose, it may be worth while to pull the hose off the radiator and check that the previous owner didn't over tighten the clamp and crack the radiator inlet housing.

[uscharalph]

On the radiator hose issue, you need to be careful not to overtighten that clamp. The radiator is plastic there. Keep monitoring the coolant level to see if you're losing coolant. Based on that you can go from there.

The coolant temperature episode you had, might be explained better in some older threads than what I can, but basically when you turn the ignition off, the engine can continue to heat up. There are not fans blowing on the radiator and coolant is not flowing by the engine. Thus when you restart the car after a short time the needle may shoot up for a very short time then drop to normal. You need to monitor any overheating till you get it sorted out.

[JonE]

Welcome Aaron,
The dipstick for tranny has that cap on it with what looks like a triangle. If you rock that cap in the direction of the "arrow" (the triangle) then it releases the dipstick and you can pull it out. You might have to try it in either direction until you "get the feel for it". It was tricky at first for me and my indy didn't even know how to remove it properly!
I use the Mobil 1 0-40 in my 535, but blended dino oil with synthetic for the first oil change to make sure the thing didn't suddenly start leaking or consuming oil. Now it is synthetic after the second oil change and I won't look back.
Also, if you have any records on you car and it indicates regular tranny fluid changes, that generally is a good indication and feel free to change the fluid. Typically between 3-4 qts drains out and I always measure what drained out and put back in exactly that amount (if tranny fluid levels were normal on the dipstick). You can also change the tranny filter and gasket if you'd like to service the thing more thoroughly. Get the Bentley manual for this car, it comes in handy!
Good luck,
JonE

[Bill R.]

limited slip additive in there, you can get it at almost any auto parts store.
Item 2, the radiator hose, this radiator is known for the neck snapping off right where the hose is attached, yours may already have a hairline crack and thats what your actually seeing leak... If its looks ok then remove the hose and clean up any buildup on the hose and radiator neck then reattach with a new hose clamp and see if it will seal up.
Next item the hot soak temp at 3/4 is normal, the gauge seems fairly sensitive to small changes and really looks like a dramatic change but it usually cools down to normal in a minute or so. Normal.
Next time, the dipstick cap for the transmission will have an arrow on the top of it, push the cap sideways in the direction of the arrow while pulling up and the dipstick will come out.
Next . Oil, I am in arizona and my ambient is as high or higher. I use mobil one synthetic 0w40, bmw synthetic is 5w30 and it meets all the specs just fine. The newer synthetics in the lower weights exceed all the requirements that the heavier 20w50 nonsynthetics had when the car was new. I've run 5w30 and 0w40 both in my 535 with no problems..
Next the shift problem is the switch, its gummed up internally by someones spilled soda pop or coffee making it intermittent.

Hi folks,

I just bought a 1990 535i, 128k miles, auto trans. I have several questions that perhaps some of you could help me with.

I didn't buy this car for relaibility - mostly I bought it because I want (need!) RWD and refuse to buy the trash detroit sells. I plan on it being tempermental, and that's OK. I've been looking for a 535 for a while, and I really like the layout of the straight big six motor. I plan to perform all regular maintenance, and have done all the work on my japanese cars. But this is my first german car.

Items I've seen come up over the past two days are:

There is a groaning sound coming from the rear of the car when turning at low speeds. It only occurs when turning, never going straight. I'd assume wheel bearings, except it happens equally when turning either direction. It almost feels like something is grabbing / tugging back there. Is there something else in the suspension? A trailing arm bushing perhaps - that would cause the tires to fight against each other? The tires are spankin' bran new, so I can't tell if there will be any wear patterns yet.

It seems to be leaking coolant from the upper radiator hose where it meets the radiator. It has a screw type clamp on it. Is that correct, or should it have a spring clamp? It's rather tight, and I don't want to break the radiator by clamping down on it too hard. The hose seems fine, as does the radiator. It just leaks. My fear is a leaking head gasket causing excessive pressure build up, but my local european auto mechanic disagrees (after an over the phone diagnosis). Ambient temperature yesterday was 98 degrees. The needle stays less than a hair's width above the 1/2 mark on the gauge. After shutting off while hot and restarting 20 minutes later, the needle sprung up to the 3/4 mark, but fell back down to 1/2 after driving for a few minutes. I imagine the sensor was just sitting in a hot spot and went back to 1/2 after the coolant started flowing. I don't know any repair history, and I know this car is prone to overheating. Shall I just replace the clamp? Flush the system for good measure? Or be paranoid and start replacing parts for fun?

And: I can't check the transmission fluid. It doesn't have a dipstick (or so it seems to me). Am I !? There is just a cap on the tube where the dipstick would go, and I can't remove it. Was this a no-tamper device for the US market to drive more customers to the service dept?!

And: Should I pay $50 to have the oil changed by the dealer so they can reset that service interval thinger? Or should I do it myself? The manual doesn't specify oil change intervals, so I'm thinking it's doing some kind of algorythm to determine, by its self, when it wants new oil. Maybe an hours of operation combined with number of revolutions, or something? I like to honor that, if that's what it's doing. But if I can't reset the service indicator, then I'd have to just start doing it based on milage.

And: The owners manual says that 10-40 oil should be used between 20 degrees and 70 degrees. 10-50 oil lets it go up to 80 degrees. But here in Utah we're routinely around 100 degrees. That would call for 15-50! That seems absurdly thick! I know this motor was used by BMW for decades, and it's probably an older design - but should I really put 15-50 oil in it?!

Finally: If I put the transmission into manual shift mode, it does it every time. If I attempt to put it back to automatic, it does it about 1/2 the time. I have to keep driving and fiddling with it, and eventually it switches back. Is that a problem with the switch, or with the transmission?

Thanks for listing to all my questions! I want to take good care of this car that really appears to be in excellent shape for its age at this point.

Aaron

[aaron]

limited slip additive in there, you can get it at almost any auto parts store.

Aha. It has "positraction", not even LSD. I'll have to read more about that. Anyway, I put some additive in it and the groan was 80% eliminated. Probably good enough - unless you suppose the remaining 20% groan is doing any damage in there. The gear oil in the diff looked clean.

Item 2, the radiator hose, this radiator is known for the neck snapping off right where the hose is attached, yours may already have a hairline crack and thats what your actually seeing leak... If its looks ok then remove the hose and clean up any buildup on the hose and radiator neck then reattach with a new hose clamp and see if it will seal up.

I found it. It's a small crack in the radiator where the overflow tube attaches above the upper radiator hose. It leaks a bit and dribbles down the radiator . . . and it seems to have pushed out about a quart of water in 50 miles. This should probably be my next maintenance item. The local repair shop quoted $330 to replace it with a nissin brand (including labor).

Is Nissin OK? And are there any special tools required for this if I do it? Do you suppose it's in danger of breaking and leaving me stranded, or could it last like that forever? If so I could spend that $300 on the steering joint knuckle instead . . .

[uscharalph]

I just installed a Nissens radiator with my brother. So far there's been no problems at all, but with just a few hundred miles on it it's too early to comment on the brand. I read a lot of posts around here and got pretty good feedback from others who used Nissens. Got mine for $179.50 on eBay.

It's really not that tough a job. There's so good writeups around here and a Bentley manual should always be used.

[LMUNick]

I've had Nissen's in other cars and they've been fine. Check out the other thread re: cooling problems, if you decide to do it yourself to make sure the cooling system is bled properly, especially with the bix sixes- Good luck and have fun!

[Jeff N.]

Full synthetic. I'd consider swapping over to that.

[callen]

1. Do all work yourself..really easy for anything you'd ever have to do to your car....
2. Call BMA autoparts...for most of your stuff...go to dealer for rest.....
3. Warning you will fall in love with your car......be prepared....4. This board and it's members are the best..they will get you through anything your car has to offer...do use the search engine...you'll get tons of info...
Finally RIGHT NOW...buy a Bentley Repair Manual for your car....you will use it often and it's absolutely excellent.

I've owned alot of cars and have a few now...but nothing compares to my 535