My E9 burns about 1 quart of oil every tank of gas -should i use Moly E.P.?

scottevest

scottevest

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I just bought a 1974 3.0cs. It runs great, but it is consistently burning about a quart of oil every time I refuel. I was told when I purchased the car that it didn't burn "that much" oil. I live at ~6000ft altitude, so that may be causing it in part. Someone told me that if you burn more than 1/2 quart of oil every 400 miles or so, it was time to rebuild the engine. I just had a ton of work done before I had the car shipped, so I am very disappointed that this has happened, but not sure if it is a big deal.

The engine runs very strong, and other than some blue smoke when I accelerate or warm up the car, and having to add a quart of oil every tank of gas, it's not that big of a deal.

My local shop suggested Moly E.P. Engine Oil Treatment: http://www.schaefferoil.com/engine-oil-treatment.html. Any thoughts?

I had a 1984 Alfa GTV 6 with the same problem, and it wasn't a big deal, just minor inconvenience.

Otherwise, loving my coupe.

Scott
 
Sounds like the bottom end, which is pretty rare with BMW engines. It may have been run low on oil in the past and scored up the cylinders, or maybe has more miles on it than BlueMax! ;-)
 
If it is burning a quart of oil per tank then I don't think an additive will have any effect - too much is getting by the seals and rings into the compression chamber.
 
First confirm the oil is of the type recommended. BMW specified a heavy weight oil 40 or 50 weight or multi equivalent. It's a common mistake until you realize it. Thicker is better for a normal coupe. If you've been adding 10-30w- don't. I personally don't run synthetics either in my older cars; there are a myriad of reasons that add up to just don't. Oil made today is not the same formula of yesterday. Change your oil and do it frequently; not by mileage if you don't drive it much. I generally drive 500 miles or less a year- I change two or three times a year by the clock or by looking at the dipstick when the oil starts to turn darker and not mileage as sulpher deposits turn to acids and then... well just ask Bluemax- the key is proper preventative maintenance and you can enjoy many carefree miles!

A moly additive or additives in general can be tried; but it's a crapshoot. There are better additives for softening valve stem seals; but follow the instructions; more is not better. The great debate continues.

As Dang says, bottom ends tend to last a long time( High nickel content blocks). Your car runs much too well for it to be a big issue. It is original and never cracked open.

I would read all my plugs with them removed to see if it was common to all or isolated somewhat. Post the picture here if you like for opinions.

That said the next course of action is the head and replacing the valve stem seals which get hard and brittle and in doing so allow oil to enter the combustion chamber and burn.
 
scottevest said:
I just bought a 1974 3.0cs. It runs great, but it is consistently burning about a quart of oil every time I refuel. I was told when I purchased the car that it didn't burn "that much" oil. I live at ~6000ft altitude, so that may be causing it in part. Someone told me that if you burn more than 1/2 quart of oil every 400 miles or so, it was time to rebuild the engine. I just had a ton of work done before I had the car shipped, so I am very disappointed that this has happened, but not sure if it is a big deal.

The engine runs very strong, and other than some blue smoke when I accelerate or warm up the car, and having to add a quart of oil every tank of gas, it's not that big of a deal.

My local shop suggested Moly E.P. Engine Oil Treatment: http://www.schaefferoil.com/engine-oil-treatment.html. Any thoughts?

I had a 1984 Alfa GTV 6 with the same problem, and it wasn't a big deal, just minor inconvenience.

Otherwise, loving my coupe.

Scott
Click to expand...

i agree with the previous comments by the "old brothers", but i will add this post because i have the same case as you

1- check which type of oil you are using, it must be 20w50 mineral oil
2- you say you have blue smoke in warming up the car and accelerations, ok, and what about when you do engine braking going down hill ?
(my case is this: when i come down hill using brake engine, no blue smoke can be seen in the exhaust, but when i reach the end of the hill, and i start kicking the accelerator, a clowd of blue smoke will follow me for about 40 seconds)
3- check the engine compression (each cylinder)
4- check the sparks, the electrode (colour, ...) and the thread (clean-oily)

share the results with us

regards
 
My replies to your questions

see MY REPLIES IN ALL CAPS

deQuincey said:
i agree with the previous comments by the "old brothers", but i will add this post because i have the same case as you

1- check which type of oil you are using, it must be 20w50 mineral oil

IT IS 20W50

2- you say you have blue smoke in warming up the car and accelerations, ok, and what about when you do engine braking going down hill ?

I HAVEN'T NOTICED/LOOKED THEN, BUT WILL. I JUST GOT THE CAR BACK FROM THE SHOP, AND IT RUNS AMAZING. MUCH BETTER THAN BEFORE. THEY ADJUSTED THE CARBS FOR ALTITUDE AND LOWERED THE IDLE. IT MAY HAVE FIXED THE ISSUE. I WILL REPORT BACK THIS WEEKEND.

(my case is this: when i come down hill using brake engine, no blue smoke can be seen in the exhaust, but when i reach the end of the hill, and i start kicking the accelerator, a clowd of blue smoke will follow me for about 40 seconds)
I WILL TRY.
3- check the engine compression (each cylinder)
THE SHOP SAID COMPRESSION WAS FINE, BUT NOT SURE IF THEY CHECKED EACH CYNLINDER.
4- check the sparks, the electrode (colour, ...) and the thread (clean-oily)
WILL DO, BUT THEY SUPPOSEDLY DID A TUNE UP BEFORE IT LEFT.

share the results with us

WILL DO

THANKS SO MUCH FOR ALL YOUR HELP. I DO LOVE THE CAR.



regards
Click to expand...
 
ok, another one !

over your answers, in blue this time:

1- check which type of oil you are using, it must be 20w50 mineral oil

IT IS 20W50, mineral ?, then great !

2- you say you have blue smoke in warming up the car and accelerations, ok, and what about when you do engine braking going down hill ?

I HAVEN'T NOTICED/LOOKED THEN, BUT WILL. I JUST GOT THE CAR BACK FROM THE SHOP, AND IT RUNS AMAZING. MUCH BETTER THAN BEFORE. THEY ADJUSTED THE CARBS FOR ALTITUDE AND LOWERED THE IDLE. IT MAY HAVE FIXED THE ISSUE. I WILL REPORT BACK THIS WEEKEND.

it is nice that you have a shop that can adjust+syncro the carbs, that is really good news. but...i don´t think that will fix the oil consumption ??

(my case is this: when i come down hill using brake engine, no blue smoke can be seen in the exhaust, but when i reach the end of the hill, and i start kicking the accelerator, a clowd of blue smoke will follow me for about 40 seconds)
I WILL TRY.
3- check the engine compression (each cylinder)
THE SHOP SAID COMPRESSION WAS FINE, BUT NOT SURE IF THEY CHECKED EACH CYNLINDER.
pardon me ?ha, ha, ha.:-D
how can they say the compression is fine without showing you the figures ?, the compression is not subjective, there is a certain value in bars, or mmHg that you should meassure, there is a relative difference between cylinders that is acceptable...so you´d better ask for the "compression chart results", it is a paper in which the compression is shown for each one of the 6 cyl

seriously, it is not your fault (i don´t like to give the impression of being rude), but workshops sometimes drive me crazy !

4- check the sparks, the electrode (colour, ...) and the thread (clean-oily)
WILL DO, BUT THEY SUPPOSEDLY DID A TUNE UP BEFORE IT LEFT.
i own my e9 since 2005, i needed 2 years to realize that i can not trust on ANY workshop and that i have to do/check everything on my own !!, and always count on the opinion and help of the gentlemen of this forum, they are great !

regards
 
deQuincey said:

i own my e9 since 2005, i needed 2 years to realize that i can not trust on ANY workshop and that i have to do/check everything on my own !!, and always count on the opinion and help of the gentlemen of this forum, they are great !

regards
Click to expand...

I fully agree. Many so called experts shops will happily mess with an old BMW, but very few are worth their fee. And even the best are usually beaten by the time and dedication I´ll be happy to invest since I want my car to be as good as it can be. I´ve ended up doing most all work myself.

Agreee on the knowledge and helpfullness of the crowd as well. Especially this forum. Very nice atmosphere (tough I do miss chicane soimetimes...) and excellent knowledge and helpfullness. Especially 61porsche and the picture stories you post.

Only body and paint, I won´t do. A five year old can get better results than me on both.
 
Some answers

Only smoke when accelerating hard from first gear, and white/bluish smoke. Not a ton of smoke. No noticeable smoke in other gears or when downshifting
Car runs very string. MUCH smoother and stronger than before the carbs were adjusted for altitude

Very fun to drive
Asking about compression numbers on Monday

Thx for all your help
 
scottevest said:
Only smoke when accelerating hard from first gear, and white/bluish smoke. Not a ton of smoke. No noticeable smoke in other gears or when downshifting
Car runs very string. MUCH smoother and stronger than before the carbs were adjusted for altitude

Very fun to drive
Asking about compression numbers on Monday

Thx for all your help
Click to expand...

that is good news !
anyway: keep an eye on the oil dipstick and check the oil consumption regularly
and yes, share your compression figures with us !
regards
 
Oil smoke on deceleration (down hill) is usually valve guides/seals...

If you coast going down hill and when you accelerate you see a cloud of smoke that is usually worn valve guides and/or hard or damaged valve guide seals. The first thing I would check is the plastic Valve Guide Seals for damage or to see if any have popped off...

Back in the old days when there were a lot more vintage MBs, BMWs, Porsches etc on the road an honest mechanic would offer you the option of a Valve Job (replacing the valve guides, valves,seats etc) $1,500 or the temporary/band aide fix of just replacing the valve guide seals for only $200. The cheap fix was usually good for 5,000-10,000 miles which in our cars today would be years...

On several occasions I got lucky because they found cracked seals or seals that had just popped off and the repair was permanent!

They would pressurized the cylinder with air and remove the retainer/springs and put new seals on. I remember having cars that smoked a lot being almost totally fixed by replacing just the seals. This only worked the first time and if your engine was totally played out (totally worn ring,guides etc) you were SOL...
 
Oil consuption may also go down with regular use. I don´t have a theory as to why that is, it´s just my experience.

Overall engines that have stood for a long time or been driven only sparingly seem to benefit from a long (and condtion permitting hard) drive.

They´ll either be better than before or something breaks for good. Either way, you´ll get clarity....

Take a weekend and drive it hard and long...
 
Oil Doing better

I went for a very long, and amazing ride from Sun Valley, Idaho, through Stanley, towards Challis. Amazing views, twisty roads, lots of elevation changes. Round trip over 200 miles or so. Car drove AMAZING, like a zillion times better than when I first got it a few weeks ago. I can't imagine synchronizing the carbs could have had that much of an effect, but apparently so. The shop also adjusted the idle, but I don't see how that could do anything either.

Well, other than driving very well, when I filled up the tank, it was about 1/2 full, it was down only about 1/4 on the dip stick from what I last remembered, so I didn't even add any more. It is now at 1/2 level.

I think perhaps you were right that the car may just have been sitting for awhile and not driven hard, and that's all it needed. It doesn't seem to be blowing that much dark/blue/white smoke, other than when I am warming it up, presumably with the choke engaged.

Next task is to figure out how/when to operate the choke. I was told to pump the accelerator once, about 1/2 way, or more if really cold, then start normally, without pumping. This seems to work, but the idle is not much higher when I did this but expected it to be higher, and LOTS of smoke comes out. Is this right?

I must say that I absolutely LOVE this car. I had a 635 CSI, but always wanted this car, and really do love it.

One last (well no promises there won't be more questions) question: Although I am trying hard to keep it dry, when it does rain, which is infrequent here in Sun Valley, is there any problem spots I should dry immediately, e.g. does water tend to gather anywhere?

Thanks so much for all your help.

I will post some videos of my drive shortly.

Scott
 
Fast idle is controled by the choke. It's usually around 1700 rpm. A screw located in the choke housing and accessible with the throttle wide open that you see through an opening down low on the choke housing of each carb. A full turn is about 300 rpm. So start with a half turn in each. Or do one at a time- your tach will go to about 1200 with only one choke; do the next and you should be close.

I set mine at a lower rpm; say 1200. Sometimes it takes a moment or two for the rpms to go up depending on how much you push the accelerator down and your squirters are working. ( Rich) I tend to run towards the rich side anyway. But there should be a point where the engine warms and gets a little smoother; when the enrichment/ choke stops. Couple of minutes or so and your rpms drop when you blip the throttle.

There's a procedure with pictures in the repair manual; registry link above, then information tab.
 
Dry any area where water has gathered, around the plenum where wiper mechanism and heater fan reside. Be sure water doesn't drip from windshield seal into glove box, be sure you have a good trunk seal.

Check your dipsticks markings, I am not sure that one mark equals only one quart, I think it is more on mine.

Depress pedal all the way to set chokes, use pedal if needed as it fires, it should rise to 1700 as Jerry said.
 
scottevest said:
Well, other than driving very well, when I filled up the tank, it was about 1/2 full, it was down only about 1/4 on the dip stick from what I last remembered, so I didn't even add any more. It is now at 1/2 level.
probably you did it well, but for a precise check of the oil level i do compare it always when the engine is cold, so before start the ride makes the reference level, and then the day after comes the check

also chris commented, from one line to the other in the oil dipstick, it is 1,5 liter !!

I think perhaps you were right that the car may just have been sitting for awhile and not driven hard, and that's all it needed. It doesn't seem to be blowing that much dark/blue/white smoke, other than when I am warming it up, presumably with the choke engaged.

Next task is to figure out how/when to operate the choke. I was told to pump the accelerator once, about 1/2 way, or more if really cold, then start normally, without pumping. This seems to work, but the idle is not much higher when I did this but expected it to be higher, and LOTS of smoke comes out. Is this right?
when i started my car, i pump the accel once, the iddle goes immediately to 1700rpms, then when average temp reached another kick in the accel, and i get the iddle fine, (before rebuilding my carbs the iddle was not going directly to 1700, but some sort of 1200, and then as it warmed up, increased until 1800, i think that the cleaning did the miracle)

one question: when you say LOTS of smoke in this condition, are you sure that is not steam ?, i mean, water condensed in your exhaust after your yesterday´s ride gets the hot from the exhaust and evaporates, probably is a mix of water and some residues too, can you check it ?

I must say that I absolutely LOVE this car. I had a 635 CSI, but always wanted this car, and really do love it.
i know that feeling !!:-D:-D

One last (well no promises there won't be more questions) question: Although I am trying hard to keep it dry, when it does rain, which is infrequent here in Sun Valley, is there any problem spots I should dry immediately, e.g. does water tend to gather anywhere?
sorry, no experience in this issue

Thanks so much for all your help.

I will post some videos of my drive shortly.

Scott
Click to expand...

here is a video of my cold start, hope it helps:

http://e9coupe.com/forum/showthread.php?t=8846

check the first video, you can see how all the procedure takes place, and visually what effect the first kick of the accel has in the throttle butterflies, it is very interesting !
 
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scottevest said:
http://www.youtube.com/watch?v=tdiGOdsT6TA
Click to expand...

i will say, yes, water, probably condensation, really a lot of that, i don´t know in which climate you are living, but it seems that your exhaust is retaining a lot of water, you can see when you put your hand near the exhaust, that the smoke is really vapour,

then the black drop in the floor, right, i can have a similar issue when i stop the car for a while and then the next run will begin with that on the floor, in my opinion is that the water inside the exhaust is mixed with particles coming from a bad combustion (similar to coal powders), then the blow of the smoke coming through the exhaust is going to throw that away, and it will fall close to the exhaust bottom

your engine probably had been burning a non correct mixture for a while, and that results in unburned particles, those particles will be also in the sparks and inside the cylinders, the valves heads, and all the way through the exhaust, you can live with it, the next time you do the engine-head they will clean it for you

anyway, it is a lot, so consider the possibility of cooling water getting inside the engine ?, have you checked the coolant level in a regular basis ? you should do !

how is your temperature reading ? when iddling, and also when riding those long rides ?

regards
 
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