Author Topic: New member/318iS owner with a question! (Read 3169 times)

EdGrip · « **on:** November 20, 2014, 01:32:43 PM »

Hello!
Firstly, the following has also been posted on the r3vlimited forums - I'm just getting a feel for both forums, and looking to pick as many knowledgeable brains as possible. Hope this is okay.

I've just bought a 1990 318iS - the car comes with a bit of MOT history, but no service history. But it's very straight body-wise, interior-wise, the engine sounded in good condition and the car generally gives the impression of having been looked after, so I decided it was worth the risk.
Naturally, the first thing to do was replace all filters, spark plugs, and put in fresh oil.

Here's the odd bit - I gave this to my local mechanic to do - he's been working on our cars for 20 years. He said that he put 5L of oil in, and left it for a few minutes, and checked the dipstick - nothing. He double-checked the internet for sump-capacity specs, but all sources said that 5L should be plenty. He put in another litre, and another - after a few minutes, it was just registering on the tip of the dipstick. He started the car for a moment and then switched it off again - now the oil was reading way above maximum on the dipstick. He drained off some, til it was within range on the dipstick. He started the car and stopped it again. Oil way above maximum again. He did this a couple more times til the level stabilised near the max mark, but the car has still got almost a litre (about a quart) more oil in it than it should have. He said he's never seen a car behave this way. I will keep a close eye on the dipstick over the coming days, but I just wondered if any of you had encountered this, or know what it might be?

Also, a PO has had some trouble with the nearside main beam, and has removed the fuse and taken a tap from the offside main beam to power the bulb. This modification has ceased to work. I'm a boring pedant so I want to fix it properly; does anyone have a wiring diagram, and would they be kind enough to send it to me?

Thanks all, and hello! I'm looking forward to learning to trust this car and being a member of the E30 gang.

- Ed

DesktopDave · « **Reply #1 on:** November 20, 2014, 03:22:26 PM »

Great to have you on board, welcome to the 'club!

I'd wonder about the total capacity of the engine, rather than the sump capacity. I suspect that the specified 4.5L is the sump capacity...so may not account for the oil filter housing and other slight accumulation around the motor. I wouldn't think it'd be much more than 5L total though. Keep in mind that the E30 and E36 motors are likely slightly different in capacity, as the sumps are different.

I typically have little left over from a 5 US quart jug (4.6L) when I do an oil and filter change.

Have you double-checked the part number on the dipstick? IIRC the M42 part isn't the same as the M44. It's not impossible to think that someone swapped in the wrong part some time in the past.

The M42 is pretty famous for leaking oil, but that's over the top, LOL.

That makes me wonder if the oil filter housing has a check valve. An oil filter housing that's draining would be bad on start up. I'll verify and get back to you.

EdGrip · « **Reply #2 on:** November 20, 2014, 03:26:47 PM »

Thanks Dave!
The mechanic's first guess was that it was the wrong dipstick. I will investigate tomorrow.

EdGrip · « **Reply #3 on:** November 21, 2014, 05:11:02 AM »

Right, here's a photo of the dipstick with part number. Oil level is still too high. Hate draining oil...

DesktopDave · « **Reply #4 on:** November 21, 2014, 08:18:58 AM »

According to bmwfans.info here, you're right on the money.

If the motor runs well, don't worry about it. It's just oil in the sump. I've overfilled cars before, and it's a brief but spectacular event.

There are a few sticky issues with the M42 in these E30s...since you're draining the oil anyway, here they are:

Did you or your mech pull the lower pan to check the small bolts holding the upper pan to the block? They have a habit of wiggling loose. In bad cases, you'll find a bolt or two. When I did mine, there weren't any bolts but I did note bolt-shaped imprints in the sump and oil pickup. We usually put a dab of blue threadlocker on them to keep them in place. Don't over-torque them, they're small and fairly easy to strip. Factory spec is less than 9 ft-lb (12N-M). Here's Sheepdog's writeup.

While you're looking at those pics, you can also see the oil pressure relief valve (next to the oil supply passage, pics 3,4,5) in the block. Granted, you have to pull the upper oil pan to get at it, but it's been superseded with an updated part. I'm not sure if this has the updated PN, but here's a diagram. If he goes in there, be sure you update.

DesktopDave · « **Reply #5 on:** November 21, 2014, 08:37:12 AM »

The oil drains clear, right? No signs of coolant or petrol contamination? Does the oil overflow only after you've run the motor? What if you just waited overnight? You could also get one of those sump pumps & drain it via the dipstick tube. I've noted that the motor runs well on very thin oil (I've used 5w20 in the past), but that it puts far less metal in the oil with a nice thick 15w50.

Have you removed the cyl head cover to check out the cam box and see if the drainbacks are clear? Granted, they're covered up by the exhaust cam box, but you'd be able to see if oil is pooling up top. You'll want to do that regardless just to check out the cam chain drive sprockets. Pointy ones are bad...flat topped ones are good. I don't want to thread-jack here, but BMW's original timing chain tensioner wasn't perfect; they're updated the M42 with the M44 part to resolve that issue. Having said that...I've been running the original one along with pointy gears since I've owned the car. I'll just swap the gears down the road, or (better yet) install an engine with the updated cam cases.

I have no real information to prove my radical theory, but I suspect the later tensioner overloads the chain deflector sprocket, causing far larger problems down the road. We've seen too many blown-up bearings and even sheared mounts.

EdGrip · « **Reply #6 on:** November 23, 2014, 10:04:11 AM »

Seems to have settled down to a sensible level now. I'm loving this car, although I feel it's too "good" for me - I'm used to driving �400 Ford Fiestas!

Thanks for your advice - I'll get stuck in to that if it ever stops raining.

Author Topic: New member/318iS owner with a question! (Read 3169 times)

EdGrip

New member/318iS owner with a question!

DesktopDave

Re: New member/318iS owner with a question!

EdGrip

Re: New member/318iS owner with a question!

EdGrip

Re: New member/318iS owner with a question!

DesktopDave

Re: New member/318iS owner with a question!

DesktopDave

Re: New member/318iS owner with a question!

EdGrip

Re: New member/318iS owner with a question!