Checking out a 97 740iL tomorrow, read the buyers guide but have a few quick question

[cutchemist42]

So checking out a 97 740iL tomorrow and had a few questions. Just some details:
-178,000kms (110,000 miles) and the vehicle is safetied. This is a big deal in Manitoba as the safety restrictions can be pretty tight for even cars from the 90s, so its a selling feature.
-Im a pretty big DIYer beside for taking out engine or dropping tranny. Have done timing related work on engines in past, albeit there were motorcycles. (Do have access to a lift if needed tho, just never had to yet)
-Also, this car is not being relied on to be a daily commuter.


Just a few questions now:

-Read about the timing chain guide issue. Is this something most owners will have experienced and have done a repair on before? Heard if it has the problem it sounds like a bag of nails? As I understand, if timing chain guide goes, its not catastrophic for the engine as long as you get off the road soonish and repair?
-Thermostat harness burning up. Where will the harness be if I inspect tomorrow?
-Oil bolts. Read the repair and it sounds pretty straightforward. Other than taking off the pan theres no way to notice if it has the problem?
-I live in a pretty extreme driving environment in Winnipeg. Any idea if these hold up well in the cold?
-Is the AT a ticking timebomb at this point? Any signs during an inspection beyond the usual feel of shifting that the AT is bad?
-Wobbly rad fan indicating bad water pump. Will I be able to get to this in their driveway during a quick visit?

Thanks for the help!

[XAlt]

you can check the water pump for play in the driveway, it's easily accessible.
trans is a ticking time bomb IMO just don't beat on it and do a fluid and filter change with oem filter and o ring.
i haven't had any problems with my e38s in the cold weather, although some people have had door handles breaking off among many other odd cold weather related issues

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another thing--the timing guides don't fail as often or as soon as the 99-01 year e38s, so you shouldn't have to worry about your guides at ALL

He should have a plan to dump it or the cash to fix it at all times, plastic is plastic and NVs aren't all that much better, although guide failure rates are still way overblown by forums. Anyways, I can find non-TU cars with broken guides all day every day, and even some M60 cars show wear.

Since it's a 97, he might have a 5HP30 which is far from a time bomb.

[cutchemist42]

So been doing some more reading on the timing guide. Basically if it goes, most people dump them? At the same time, is there no regular intervals for that failure? If I got 1-3 years out of the car I'd be happy. If it died within the next few months I'd be upset.

[cutchemist42]

imo i can't see why u wouldn't get some more miles out of it as long as it sounds healthy, but obviously there is no guarantee...
pull the oil cap and take a quick peak into there and see if things look sludge - less and golden in color

Thanks!

[cutchemist42]

So another question as the more i read about the timing chain guide the more Im hesitant......how much preventive work does replacing the tensioner do?

[psjr]

-Read about the timing chain guide issue. Is this something most owners will have experienced and have done a repair on before? Heard if it has the problem it sounds like a bag of nails? As I understand, if timing chain guide goes, its not catastrophic for the engine as long as you get off the road soonish and repair?

I don't think most owners would have experienced and repaired it before. The noise is the chain slapping on the timing covers, and it sounds pretty much like a chain slapping on some timing covers. It is not catastrophic in almost all cases.


-Thermostat harness burning up. Where will the harness be if I inspect tomorrow?

The big fan on the engine is on the water pump pulley. So you can locate the water pump that way. To the left of the water pump is the thermostat. The thermostat should have the lower radiator hose connected directly to it. The plug for the problematic harness is on top of the thermostat. There is also a plug for temperature sensor on top of the water pump that looks the same.


-Oil bolts. Read the repair and it sounds pretty straightforward. Other than taking off the pan theres no way to notice if it has the problem?
Correct.

-I live in a pretty extreme driving environment in Winnipeg. Any idea if these hold up well in the cold?

Yes, German cars are much better made for cold weather than other makes. Heated windshield parking area, heated washer nozzles, headlight washers with heated nozzles, heated side mirrors, lots of hood insulation to keep the engine warm. All of those are standard except the headlight washers, which for all I know may have been standard in Canada. Heated steering wheel is my favorite option.


-Is the AT a ticking timebomb at this point? Any signs during an inspection beyond the usual feel of shifting that the AT is bad?

I would say yes in general to ticking timebomb, but there's not much you can inspect. The main failure modes of these transmissions are sudden.
You can check the build date on the door jamb. Before 01/97 is the 5HP30, after 01/97 is the 5HP24. Will also be obvious from the size and shape of the transmission oil pan if you can look under it.


-Wobbly rad fan indicating bad water pump. Will I be able to get to this in their driveway during a quick visit?

See above about water pump location. You won't be able to wiggle it by hand with the car off because of the belt tension, but maybe you can observe how wobbly the fan is while running.

[XAlt]

So another question as the more i read about the timing chain guide the more Im hesitant......how much preventive work does replacing the tensioner do?

Don't be scared, but always have a backup plan or go for the M60\M73 cars. The updated tensioner helps with startup rattle for sure. I've seen a 300k mile facelift car on original guides, but I've also seen some that failed at 80k. I'd say with a proper OCI and new tensioner, you're looking at 170-200k miles as the mean time between failure.

But then again, plastic gets older, and dry rot is an issue, and now you see the M5's S62 engine that was touted as immune to these problems starting to fail in colder\ultra hot climates. Also, if you're unsure about the trans, a 95-96 car or a V12 will have the more durable one.

[Mayorchuck]

It's become evident that the guides deteriorating is as much as about age as is it mileage. I've had 3 part cars, all '96. Two were part cars because of failing guides. We've also had cars here with lower mileage than this car with bad guides. Point being, you cannot dismiss the guides because of the year.

[XAlt]

It's become evident that the guides deteriorating is as much as about age as is it mileage. I've had 3 part cars, all '96. Two were part cars because of failing guides. We've also had cars here with lower mileage than this car with bad guides. Point being, you cannot dismiss the guides because of the year.

Agreed

[cutchemist42]

-Read about the timing chain guide issue. Is this something most owners will have experienced and have done a repair on before? Heard if it has the problem it sounds like a bag of nails? As I understand, if timing chain guide goes, its not catastrophic for the engine as long as you get off the road soonish and repair?

I don't think most owners would have experienced and repaired it before. The noise is the chain slapping on the timing covers, and it sounds pretty much like a chain slapping on some timing covers. It is not catastrophic in almost all cases.


-Thermostat harness burning up. Where will the harness be if I inspect tomorrow?

The big fan on the engine is on the water pump pulley. So you can locate the water pump that way. To the left of the water pump is the thermostat. The thermostat should have the lower radiator hose connected directly to it. The plug for the problematic harness is on top of the thermostat. There is also a plug for temperature sensor on top of the water pump that looks the same.


-Oil bolts. Read the repair and it sounds pretty straightforward. Other than taking off the pan theres no way to notice if it has the problem?
Correct.

-I live in a pretty extreme driving environment in Winnipeg. Any idea if these hold up well in the cold?

Yes, German cars are much better made for cold weather than other makes. Heated windshield parking area, heated washer nozzles, headlight washers with heated nozzles, heated side mirrors, lots of hood insulation to keep the engine warm. All of those are standard except the headlight washers, which for all I know may have been standard in Canada. Heated steering wheel is my favorite option.


-Is the AT a ticking timebomb at this point? Any signs during an inspection beyond the usual feel of shifting that the AT is bad?

I would say yes in general to ticking timebomb, but there's not much you can inspect. The main failure modes of these transmissions are sudden.
You can check the build date on the door jamb. Before 01/97 is the 5HP30, after 01/97 is the 5HP24. Will also be obvious from the size and shape of the transmission oil pan if you can look under it.


-Wobbly rad fan indicating bad water pump. Will I be able to get to this in their driveway during a quick visit?

See above about water pump location. You won't be able to wiggle it by hand with the car off because of the belt tension, but maybe you can observe how wobbly the fan is while running.

Thanks for the reply! Any idea on when the ATs go bad or can it differ largely?

[XAlt]

Thanks for the reply! Any idea on when the ATs go bad or can it differ largely?

120-200k represents the vast majority of AT failures.

[cutchemist42]

Thanks again for the replies, the more I read the more I think I will be getting 2 years atleast out of this car, so long as I like the engine and what the owner says when I get there tonight. At the price, I think thats fine.

[XAlt]

Thanks again for the replies, the more I read the more I think I will be getting 2 years atleast out of this car, so long as I like the engine and what the owner says when I get there tonight. At the price, I think thats fine.

It's not about getting x amount of years off the car, it's about maintaining it to the point it'll last you a long time. If you're afraid the 5HP24\M62 combo will force you to dump it in two years, there are more (mechanically) reliable E38s out there.

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Also found it on some classifieds, I'd walk away just knowing about the fender damage. Plus you've already got a broken rear shade, meh interior condition, rattlecanned M-Pars.

[cutchemist42]

It's not about getting x amount of years off the car, it's about maintaining it to the point it'll last you a long time. If you're afraid the 5HP24\M62 combo will force you to dump it in two years, there are more (mechanically) reliable E38s out there.

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Also found it on some classifieds, I'd walk away just knowing about the fender damage. Plus you've already got a broken rear shade, meh interior condition, rattlecanned M-Pars.

Oh I would definitely intend to maintain it and honestly, the timing chain guide depending on getting the rental tools is something I would attempt on my own, if it was summertime. If the AT went I would not be likely to do it.

In my years of browsing kijiji, I've just never seen a V12 pop up locally. Its interesting to learn of the differences between the 2.

[racer2086]

So here's my opinion FWIW... The guides will have to be done at some point. There is no way to know when. There seems to be a correlation between a well maintained car and one whose guides last a long time. Again, that is just a correlation. We have no research or data to prove this. As an example, I replaced mine myself at around 195k miles on my well-maintained '98. They were totally fine when I did it, but they literally fell apart in my hands when I took them out. So honestly it's a crap-shoot and a matter of when not if.

The AT also follows the correlation above. If it is maintained and not beat on, it'll probably last you a long time. As these cars get into 2nd, 3rd, and 4th owners, some of them are treated like garbage and in some cases like a drag car. That transmission will fail (common sense, though, right?).

In terms of the cold...these cars have nice amenities for the cold, but I would not say they "hold up well" in the cold. Maybe if your car is seasoned to it, it may not be as bad because everything has already been dealt with. But coming from FL, my car had a lot of things to deal with in the cold. For one, the door handles and door latches can get stuck. I've greased the heck out of mine and sometimes I can't get the door to relatch when it is cold. Second, plastic breaks, including window regulators and cooling parts. Third: leaks. What doesn't leak in the warmth seems to leak in the cold. I have almost always experienced some kind of leak with the cold -- valley pan, timing cover gaskets, transmission input shaft seal, etc. Bottom line is it is a German car...it won't be as problem free as others.

Also, in regards to the lower tensioner...after having taken the whole front apart and replaced the guides, I don't know replacing the lower tensioner actually serves as preventive maintenance for guide failure. It seems to be more of a psychological peace-of-mind thing because if the chain is not rattling, then then tensioner is doing its job. IF you have a rattle or anything like that, then, yes, replacing the lower tensioner would help if it quelled the rattle.

Other than that, if it doesn't rattle, you're not really gaining anything by replacing it. The thing is simply a piston that fills with oil to put pressure on a part of the guide to tension the chain. If it's not rattling, your chain is under tension. Based on how the everything works, you get a rattle in 2 scenarios: the tensioner is defective and not maintaining oil pressure or your chain has stretched so much, the tensioner can't take up the slack. I witnessed first-hand how much the chain stretched when I replaced mine while doing the guides. It was unmistakable. However, my car was on its first tensioner at 195k miles without any issues.

[XAlt]

Oh I would definitely intend to maintain it and honestly, the timing chain guide depending on getting the rental tools is something I would attempt on my own, if it was summertime. If the AT went I would not be likely to do it.

In my years of browsing kijiji, I've just never seen a V12 pop up locally. Its interesting to learn of the differences between the 2.

Check the date on the VIN stamp, if it's a 5HP30 car it might be more appealing. Also keep in mind that MY1995 has the earlier M60B40.


Now that I think of it, $1600 isn't too bad of a price considering how few of them are around you.

[cutchemist42]

Well checked it out and being the first 7 series I've ever been in let alone drive, I really liked it. Reminded me of my family's old Park Avenue in roominess. Some thoughts/points:

-$2200 Canadian, on winter tires now. Car would not come with summers
-Owner was maybe 26, maybe still lived with his parents, bought the car to replace a W124 EClass
-Only owned it since summer and already selling, bought an Escape for work. He still had some construction equipment in the car. No service records from owner before him, he only did one oil change since getting it
-Said he was a diyer with cars. I believed him as he had a good scanner sitting in the car
-Been years since I drove a car with an AT. Having gone through a failed AT before, this felt like it was really working well.
-Im really trying to compare the engine noise of a bad one to good one but not sure Im getting it right. Didnt sound bad from inside, but maybe i dont know what to listen for
-Video of car running https://www.youtube.com/watch?v=P_CrIpZgCBU.
-Didnt see anything scary when looking at the water hoses. Area around water pump seemed dry.
-Got the VIN and did a read, its definitely a 97.
-Passenger side door was having lots of trouble. Person who came with me opened it at a first, but had to crawl out of driver door to get out. Might be the cold because it was -30 Celcius.
-Love the fact its safetied.

[XAlt]

E38 and E39 doors love to freeze out in cold weather, I've almost broken my thumb trying to force one out. Engine sounds pretty normal, no death rattle or the lot.


So the manafacturing date was after 1\97?

[cutchemist42]

Yeah the vin reader is saying 1997-03-05.1997-03-05

[XAlt]

Yeah the vin reader is saying 1997-03-05.1997-03-05

It's a 5HP24 car for sure

[gaspump]

Reading all the stuff on AT, guides, leaks, cold problems got me thinking. The 2 cars I'm looking at are a 98 750 and a 740i sport. First with 129000 miles, second with 79000. it is strange that I've bought many cars sight unseen and have never had one single major problem, knoock on wood. The v12 motor is nice, my old Jag xjs was great. So now I'm wondering. I dont drive me cars a lot, my current 525it, 2001 only has 106000 miles. I guess I should go with my gut. Film at 11. Thanks