Buying advice: Does this m62tu engine sound 100% healthy?

[mamij]

Hi Guys

I'm looking at a nice 735i from 2000.
A one owner car with only 114.000 km/70.837 miles, and full service history.
I need to confirm, that this engine sounds healthy, as I've been reading up a lot on the common chain guides and VANOS issues with these engines. This is however a low mileage engine in my eyes.

I've asked the owner to send me a few videos of the engine running in idle, to confirm that the engine is healthy. To me it sounds good, except maybe the chain on startup for a split second, do you agree, should I be worried?

Please assist if you can:





Thanks

[nike32]

Well it is hard to judge by videos, but to me sounds healthy.

Lähetetty minun ONEPLUS A5010 laitteesta Tapatalkilla

[mamij]

Well it is hard to judge by videos, but to me sounds healthy.

Lähetetty minun ONEPLUS A5010 laitteesta Tapatalkilla

Thanks for the reply .
You wouldn't say, that there is a slightly 1 second noise on startup, that shouldn't be there ?

I know my old m52 engine does this, and shouldn't be an issue on the inline 6, but I've heard that it could be the start of a failing chain/chain guides on the m62.

[clarkitect]

Engine sounds pretty good to me. Tapping at start up doesn’t mean guides are going bad, it could be bad/dirty vanos check valves, or just loose vanos. With that low miles car must sit for stretches. Might need to be driven.

[mamij]

Engine sounds pretty good to me. Tapping at start up doesn’t mean guides are going bad, it could be bad/dirty vanos check valves, or just loose vanos. With that low miles car must sit for stretches. Might need to be driven.

Well that's my plan. The previous owner (born 1925) didn't drive it a lot, was mostly garaged.
The current owner drives it a bit more, and has bought the car 16 months ago, from the first owner.
The car is still garaged when not in use.

When you say vanos check valve, you mean the two vanos solenoids right ?
I could replace these if needed.

But couldn't it just be a normal noise until the oil gets circulated, my M52 does this on startup?

[clarkitect]

There’s a check valve located behind the vanos solenoids. Unscrew the solenoids and screw a long M10 x 1.0 mm bolt into the check valve to pull it out.

I guess it could be considered somewhat normal, it’s not totally uncommon, definitely it’s noise until the oil pressure builds. Might was to replace the timing chain tensioner with the newer design in case it’s a little chain slap.

[mamij]

There’s a check valve located behind the vanos solenoids. Unscrew the solenoids and screw a long M10 x 1.0 mm bolt into the check valve to pull it out.

I guess it could be considered somewhat normal, it’s not totally uncommon, definitely it’s noise until the oil pressure builds. Might was to replace the timing chain tensioner with the newer design in case it’s a little chain slap.

I've looked at realoem with the VIN, and the only part number I could find for the chain tensioner was 11317531813.
Is this suppose to be the one with the "new" design?

Just out of curiosity, would the new tensioner put more strain on the chain guides, causing them to fail quicker?

[clarkitect]

I've looked at realoem with the VIN, and the only part number I could find for the chain tensioner was 11317531813.
Is this suppose to be the one with the "new" design?

Just out of curiosity, would the new tensioner put more strain on the chain guides, causing them to fail quicker?

That's the right part number. It superseded part number 11311736023. From what I understand the new tensioner has a much stronger spring that maintains pressure on the chain when oil pressure drops when the engine is turned off. At least that's what I have heard. A car with 70k miles may still have the old version.

And a loose tensioner that allowed the chain to slap would put more strain on the guides than an new tight one that held a more consistent pressure. At least in theory. The guides will fail eventually anyway since they are brittle plastic, but conventional forum wisdom has the tensioner as an easy preventative maintenance item to prolong chain guide life.

[mamij]

That's the right part number. It superseded part number 11311736023. From what I understand the new tensioner has a much stronger spring that maintains pressure on the chain when oil pressure drops when the engine is turned off. At least that's what I have heard. A car with 70k miles may still have the old version.

And a loose tensioner that allowed the chain to slap would put more strain on the guides than an new tight one that held a more consistent pressure. At least in theory. The guides will fail eventually anyway since they are brittle plastic, but conventional forum wisdom has the tensioner as an easy preventative maintenance item to prolong chain guide life.

Thanks for the explanation.
Another thing, would you consider doing a transmission flush or not at these miles, or just a simple transmission oil change, as I've heard the flush could cause issues?

The transmission oil has never been changed, as far as I could see in the service history.

[rslifkin]

Changing the transmission fluid certainly won't hurt. If you think it's never been changed, I'd change the fluid and filter, and then after a few thousand miles, change the fluid again (draining the pan only gets about half of the total fluid in the system).

[mamij]

Changing the transmission fluid certainly won't hurt. If you think it's never been changed, I'd change the fluid and filter, and then after a few thousand miles, change the fluid again (draining the pan only gets about half of the total fluid in the system).

I was only told by the owner, that the oil still looks clean judging by his own opinion (checked the oil himself).
Also that BMW I suppose, told him not to do anything/change it, probably related to their crappy "Liftetime" thing.

[mamij]

One more thing guys.
I've been reading up a lot on the steptronic transmission on these models, which is the ZF 5HP24.
According to the information on the net, they develop issues with the A-drum etc, all related specifically to the 5HP24.

What is your experience with this, are these issues caused by bad driving habits/abusive driving, as I believe this car has been treated well, and should not worry?
Or is it just inevitable no matter what?
In that case, at what mileage should I approx. expect this to happen?

Thanks again

[kouks]

Engine sounds healthy on the video.

VANOS rattle at startup can start to occur at about 100k miles, but will not hurt the engine unless it does not go away after a second or two. If not, then you have other issues, including possible chain guides. Chain guides usually will not go until about 130-150k miles in a normally driven engine which has had usual oil changes.

The 5HP24 has an upgraded A drum in the later models, so not as big a deal with those trannys. Usually, a normally driven car will not have trans issues until about 150-170k miles or more. If this trans shifts fine and is not slipping at all, leave alone, do not change the oil unless you think its starting to have issues. When it gets to about 100k miles, that would be your first chance to change the oil/filter on the trans. This is the 735, it does not have the higher torque of the 740, so the trans will last even longer.

In short, if this car only has 70k miles on it, it has been lightly driven by most likely an proud owner. I think you will have 70-100k miles until any major fixes will be needed. That's my unequivocal expert opinion, having never seen the car and hearing the engine over the internet :-).

Seriously though, a one owner car with 70k miles would definitely be at the top of my list if I were searching for another one.

[rslifkin]

Not changing the trans fluid because it's working fine is the dumbest thing I've ever heard. Unless you have a reason to do it more often, change the trans fluid every 50k (a pan drop only changes about half of the fluid anyway). Having worn out fluid in there isn't going to do anything good for the trans and fresh fluid won't hurt it.

[kouks]

Not changing the trans fluid because it's working fine is the dumbest thing I've ever heard. Unless you have a reason to do it more often, change the trans fluid every 50k (a pan drop only changes about half of the fluid anyway). Having worn out fluid in there isn't going to do anything good for the trans and fresh fluid won't hurt it.

What you are saying is correct IF you change fluid on a regular basis. The vast majority of used cars have never had their trans fluid changed.

In this particular case, at 70k miles, changing the trans fluid will not do any harm since this car was taken good care of, so if mamij wants to do it, it would be fine.

IF a used car has high mileage however, and the trans fluid has never been changed, there is a good chance the papers are worn. Changing the fluid in that case may shift the adaptations too far for the EGS to compensate and the trans will throw a Trans Fail Safe code.

[mamij]

Engine sounds healthy on the video.

VANOS rattle at startup can start to occur at about 100k miles, but will not hurt the engine unless it does not go away after a second or two. If not, then you have other issues, including possible chain guides. Chain guides usually will not go until about 130-150k miles in a normally driven engine which has had usual oil changes.

The 5HP24 has an upgraded A drum in the later models, so not as big a deal with those trannys. Usually, a normally driven car will not have trans issues until about 150-170k miles or more. If this trans shifts fine and is not slipping at all, leave alone, do not change the oil unless you think its starting to have issues. When it gets to about 100k miles, that would be your first chance to change the oil/filter on the trans. This is the 735, it does not have the higher torque of the 740, so the trans will last even longer.

In short, if this car only has 70k miles on it, it has been lightly driven by most likely an proud owner. I think you will have 70-100k miles until any major fixes will be needed. That's my unequivocal expert opinion, having never seen the car and hearing the engine over the internet :-).

Seriously though, a one owner car with 70k miles would definitely be at the top of my list if I were searching for another one.

Not changing the trans fluid because it's working fine is the dumbest thing I've ever heard. Unless you have a reason to do it more often, change the trans fluid every 50k (a pan drop only changes about half of the fluid anyway). Having worn out fluid in there isn't going to do anything good for the trans and fresh fluid won't hurt it.

Thanks, really appreciate your help guys .
Glad to hear about the updated A-drum, what about other issues like not going in to reverse, and could all these issues be related to the driving habits?
I however plan on changing the AT-oil (NOT flushing) as soon as I get the car, as a preventive maintenance.

According to the chain guides and the regular oil changes, I've attached an image to this post from the service history.
As far as I can see, the original owner has done the oil changes between 9.320 - 12.427 miles (included in inspection as well I suppose), to me it seems like a bit long intervals.
I hope the engine hasn't taken any damage with these long intervals.
I've always changed oil on my inline 6's at about 5.000 miles or once a year, which is why an oil change must be done as soon as I get this car.

According to the major fixes, would it be a good idea to do a cooling system overhaul at these miles, as I know the inline 6 have the reputation to fail at similar miles in this department?
What about other preventive stuff like CPS, fuel pump etc, to eliminate a stranded situation, what are the replacement intervals for these parts on the V8?

[kouks]

Trans: If you're going to change the oil, then go ahead and change the filter too with a ZF brand filter. Not going into reverse is caused by the F drum spring in the reverse drum breaking. Not a common failure except on high mileage cars, so I would not worry about it.

Oil Changes: I agree the oil change intervals are a bit long, but if he used synthetic oil it should be OK. What I would do is do a Liqui-Moly engine flush and then change the oil with LiQui-Moly 5w-40 and Liqui-Moly MoS2 oil additive. That way you will clean out the engine of most gunk if there is any, and then refill with clean oil and an excellent friction modifier, so it will run smooth. Then change it again in about 3k miles. I use MoS2 all the time, my 740i Sport DINAN gets an easy 25 mpg on the highway, which is very good for that car, and the oil additive may be part of the reason.

Coolant Flush or Coolant System re-do: Normally not a big problem on the V8 cars, like it is on the 6 cyl cars. However, since this car has spent a lot of time sitting in the garage, the rubber hoses may have become more brittle and may need changing. I would probably do a coolant flush, and then change all the rubber hoses. The radiator does not cost too much, so not a bad idea to change it, and make sure you change the fill reservior, that is usually a common failure point.

CPS and fuel pump are rare failures at low miles, so don't worry about those. Although, cars that sit in the garage may have fuel pump issues if bad fuel was used. My daughter's e46 (very low miles) lost the fuel pump at 60k miles (we got it from an older lady that did not drive it much), but my e34 lost it at 180k miles, but I drove that car every day. I would leave the fuel pump alone, unless you start getting starting problems. The fuel pumps will usually fail slowly, give you a start problem once in a while before they actually fail, so you'll have time to change it before it finally stops working. My daughter's e46 had two start problems, both times it started after she let it sit for a couple hours and drove it home. I changed it after the second time and after 15k miles, no other problems. E38 fuel pump failures are rare and usually high mileage.

Like I said before, I think the only real issues you will have with the car is leaks (oil, coolant and vacuum) because it has sat in the garage and the rubber parts or gaskets become brittle. Its not reasonable to change all the gaskets, unless you want to pull the engine and do all the seals, so its one of those things you will have to watch and see where the problem is, and fix it as you drive it.

[mamij]

Trans: If you're going to change the oil, then go ahead and change the filter too with a ZF brand filter. Not going into reverse is caused by the F drum spring in the reverse drum breaking. Not a common failure except on high mileage cars, so I would not worry about it.

Oil Changes: I agree the oil change intervals are a bit long, but if he used synthetic oil it should be OK. What I would do is do a Liqui-Moly engine flush and then change the oil with LiQui-Moly 5w-40 and Liqui-Moly MoS2 oil additive. That way you will clean out the engine of most gunk if there is any, and then refill with clean oil and an excellent friction modifier, so it will run smooth. Then change it again in about 3k miles. I use MoS2 all the time, my 740i Sport DINAN gets an easy 25 mpg on the highway, which is very good for that car, and the oil additive may be part of the reason.

Coolant Flush or Coolant System re-do: Normally not a big problem on the V8 cars, like it is on the 6 cyl cars. However, since this car has spent a lot of time sitting in the garage, the rubber hoses may have become more brittle and may need changing. I would probably do a coolant flush, and then change all the rubber hoses. The radiator does not cost too much, so not a bad idea to change it, and make sure you change the fill reservior, that is usually a common failure point.

CPS and fuel pump are rare failures at low miles, so don't worry about those. Although, cars that sit in the garage may have fuel pump issues if bad fuel was used. My daughter's e46 (very low miles) lost the fuel pump at 60k miles (we got it from an older lady that did not drive it much), but my e34 lost it at 180k miles, but I drove that car every day. I would leave the fuel pump alone, unless you start getting starting problems. The fuel pumps will usually fail slowly, give you a start problem once in a while before they actually fail, so you'll have time to change it before it finally stops working. My daughter's e46 had two start problems, both times it started after she let it sit for a couple hours and drove it home. I changed it after the second time and after 15k miles, no other problems. E38 fuel pump failures are rare and usually high mileage.

Like I said before, I think the only real issues you will have with the car is leaks (oil, coolant and vacuum) because it has sat in the garage and the rubber parts or gaskets become brittle. Its not reasonable to change all the gaskets, unless you want to pull the engine and do all the seals, so its one of those things you will have to watch and see where the problem is, and fix it as you drive it.

Thank you kouks for very detailed information .
Of course I plan to replace the oil filter along with the oil in the transmission, I've never changed any oil on my vehicles without changing the filter, and good to hear that I don't have to worry about the F-drum.

I will consider your advice about the Liqui-Moly, as I'm more a Castrol guy. It's at least what BMW recommends as an oil brand here in Denmark.

I will definitely have a look at the cooling system, but you wouldn't say the thermostat and waterpump are weak spots, in the inline 6 these need to be replaced at 60.000 miles for preventive maintenance?
Don't know if these waterpumps came with plastic impellers, in that case, it's hard to trust them.

I'll surely keep an eye on the fuel pump symptoms along with the CPS, and take it from there.

[kouks]

Castrol is fine too, any good synthetic oil, I just like Liqui-Moly. You can still use the MoS2 with Castrol if you want.

The cooling systems on the V8s are more dependable than the 6-cyl cars. You can do it two ways. One, just leave it alone for now and if you start having leaks, just don't replace the hoses, do the entire system. Or two, just change it all out now and not worry about it. I think the original water pumps were also plastic, but the V8 turns at much slower rpms so not as much mechanical stress on the impellers as in the 6-cyl. Which way you go is all about money.

If you replace the entire system, you need to consider the hoses, refill reservoir, radiator and associated hardware, fan clutch, water pump, electric thermostat, aux fan switch (on the lower hose), and what people call the "voltage regulator" - its actually the plastic adapter to the transmission oil cooler and has been known to leak or crack. You may also want to replace the hoses at the back of the engine that go to the heater core.

Another common leak is the valley pan. You will notice its leaking when you get coolant dripping from the front of the transmission housing. The valley pan is under the intake manifold. If it leaks coolant flows on top of the engine between the cylinder heads, and leaks out the back through two drain holes, which allow the coolant to drip into the trans bell housing and out the bottom. This is a big job since the intake manifold has to come off to get to the valley pan and so does the water pump and the cooling pipes attached to the pump (replace the o-rings on the pipes). A complete coolant re-do should also include the valley pan, so then you'll need to replace the intake manifold gaskets, and the oil separator at the back of the manifold. Yes, it gets involved.

If it were me, I'd just drive it and watch it. You might as well enjoy the car for a while before you have to do any major work on it. It may not have any leaks for a year or two, and by then, your life may be different.

[mamij]

Castrol is fine too, any good synthetic oil, I just like Liqui-Moly. You can still use the MoS2 with Castrol if you want.

The cooling systems on the V8s are more dependable than the 6-cyl cars. You can do it two ways. One, just leave it alone for now and if you start having leaks, just don't replace the hoses, do the entire system. Or two, just change it all out now and not worry about it. I think the original water pumps were also plastic, but the V8 turns at much slower rpms so not as much mechanical stress on the impellers as in the 6-cyl. Which way you go is all about money.

If you replace the entire system, you need to consider the hoses, refill reservoir, radiator and associated hardware, fan clutch, water pump, electric thermostat, aux fan switch (on the lower hose), and what people call the "voltage regulator" - its actually the plastic adapter to the transmission oil cooler and has been known to leak or crack. You may also want to replace the hoses at the back of the engine that go to the heater core.

Another common leak is the valley pan. You will notice its leaking when you get coolant dripping from the front of the transmission housing. The valley pan is under the intake manifold. If it leaks coolant flows on top of the engine between the cylinder heads, and leaks out the back through two drain holes, which allow the coolant to drip into the trans bell housing and out the bottom. This is a big job since the intake manifold has to come off to get to the valley pan and so does the water pump and the cooling pipes attached to the pump (replace the o-rings on the pipes). A complete coolant re-do should also include the valley pan, so then you'll need to replace the intake manifold gaskets, and the oil separator at the back of the manifold. Yes, it gets involved.

If it were me, I'd just drive it and watch it. You might as well enjoy the car for a while before you have to do any major work on it. It may not have any leaks for a year or two, and by then, your life may be different.

Sure, I'll give the MoS2 a shot .
Any particular reason, why you prefer the fully synthetic 5w-40 over 0w-30 and 5w-30, as other threads seem to suggest these two for this type of engine?

Alright, I'll take your word for it and leave the cooling system alone for now, as this is the V8. I guess I just wanted to prevent/avoid an overheating situation (blowing up the engine), caused by a bad thermostat or water pump impeller, as the block is aluminum and probably doesn't tolerate overheating (again issues common on the inline 6).

I've been reading up on the valley pan issue, but didn't seem to find any specific thread stating, at what miles this issues usually occurs?

Ind the end, I only ride about 6000 miles a year, so I hope the engine will be trouble-free for some time...

[rslifkin]

M62s aren't as easy to damage with an overheat as the 6 cylinders tend to be, although a severe overheat can hurt any engine. Personally, I'd assess the condition / age of the rad and expansion tank. If either is old or questionable, just replace them. For hoses, it should be pretty easy to tell if they're still in good shape. Water pump and valley pan, don't worry about them unless they start leaking.

[kouks]

^What rslifkin said makes good sense

i use 5w-40 because I live in the California desert and in the summer it’s 40-42C every day, plus I drive in LA traffic. In Denmark using 5w-30 in the summer and 0w-30 in the winter makes more sense, as long as you use fully synthetic oils.

[mamij]

M62s aren't as easy to damage with an overheat as the 6 cylinders tend to be, although a severe overheat can hurt any engine. Personally, I'd assess the condition / age of the rad and expansion tank. If either is old or questionable, just replace them. For hoses, it should be pretty easy to tell if they're still in good shape. Water pump and valley pan, don't worry about them unless they start leaking.

^What rslifkin said makes good sense

i use 5w-40 because I live in the California desert and in the summer it’s 40-42C every day, plus I drive in LA traffic. In Denmark using 5w-30 in the summer and 0w-30 in the winter makes more sense, as long as you use fully synthetic oils.

Thank you both .
I think I might stick with the 5w-40, as I do believe it lubricates better than the -30, I use the same oil in my m52.

What are you opinions on lowering the engine temperature with a colder thermostat, to extend the life of all hoses etc, is this a good idea to do on these engines, or should I just stick with the original?
As far as I could read, the operating temperature is at a high 108C, and I do a lot of city traffic, wondering if it can constantly hold the temp, without overheating?
Could it even extend the life of the TCG?

[rslifkin]

Running it colder will increase the life of plastic bits in the cooling system (less heat and pressure) but will carry a small efficiency penalty (and likely won't do a whole lot for power either, being that the plastic intake doesn't have major heat soak problems from what I can tell).

[kouks]

As he said above, a colder engine will be less efficient, burn richer and burn more fuel. But it will reduce stress on the engine. Since this engine is low mileage, and it can run well until about 120,000 miles without any major problems, you have a long way to go. Running the normal temperature will be fine, especially since most of the time the temperatures in Denmark are usually cold. That means much more efficient heat transfer by the radiator while driving even in the city. Make sure the aux fan (electric fan) is working properly. A non-working aux fan will stress the engine at higher temperatures and cause premature engine failure. The aux fan is a common failure item. To test it, after driving the car for even a short time, pull over and let it run. The aux fan should come on and run within a couple minutes. It may cycle on and off. Also, if you turn on the air conditioner, the aux fan should run at low speed all the time. If this is not happening, there is a problem with the aux fan or the switch that is on the lower hose from the radiator in the 2000 cars.

The colder thermostats are good for us living in the desert.