240d sat a week, hard to start cold, easy when warm, now won't start - PeachParts Mercedes-Benz Forum

caramel240d · #1 01-12-2011, 10:12 AM

Hey all, what a great forum! I have a question.. I left my 240D sitting for a week and when I started it, it took 5-10 seconds to finally start. It'll start up again fine after the initial start but when it's been sitting for a while (some hours) it takes 5-10 seconds to start again. Now it's not starting AT ALL. When I press the fuel primer (new-style black pump) I hear a squeak every time that sounds like it's coming from somewhere other than the pump itself?? I can't tell! Does the squeak every pump mean there's a huge leak? Or am I just hearing the normal operation of the hand pump...

Here's some info on it that may help to diagnose the problem: I just replaced my fuel filters on my 240D two weeks ago since I had some fungus growing, and it's been running great (I have 80% bio in there now, and used startron enzyme treatment), the clear pre-filter is full of fuel, and one of my injector nuts or something around it looks like it's leaking fuel slightly.

Is this an air leak in the fuel delivery system? The fact that it'll start easy once I get it running seems to suggest that? But it's not starting at all anymore-- so could it be something more sinister like compression? The oil pressure gauge goes up to 3 after I try to turn it over for a little bit.

Any help would be greatly appreciated!! Not only to help my car but to put my anxious mind to rest..

vstech · #2 01-12-2011, 10:17 AM

First and formost, WELCOME to the forum!
what year is your 240?
the squeak is normal, it's the sound of the fuel squirting through the filter into the return line. it means you have full fuel.

how long do you let the key sit in the glow position before you attempt to start?
how cold is it where you are?
when was the last time the valves were adjusted?

caramel240d · #3 01-12-2011, 10:37 AM

Hey vstech, thanks for the warm welcome! My 240 is a 1980. Thanks for the tip about the squeak.

I let the key sit in the glow for about 5 seconds before it goes out, and that always works.

It's 43F right now and I've started it colder. The fuel isn't at it's cloud point.

I have no idea when the valves were last adjusted. The last owner took pretty good care of it. Could that prevent the engine from even starting?

I should mention I tried turning idle knob all the way left and depressing accelerator, also while turning over, like the manual says to do for cold weather. No luck.

strelnik · #4 01-12-2011, 10:45 AM

Quote:

Originally Posted by caramel240d

Hey vstech, thanks for the warm welcome! My 240 is a 1980. Thanks for the tip about the squeak.

I let the key sit in the glow for about 5 seconds before it goes out, and that always works.

It's 43F right now and I've started it colder. The fuel isn't at it's cloud point.

I have no idea when the valves were last adjusted. The last owner took pretty good care of it. Could that prevent the engine from even starting?

1. When I got the first 1980 240d I had, I found out that the short neoprene fuel line connecting the two metal lines had a crack which periodically let air into the system. Now when I get a car, the short pieces of neoprene are replaced immediately for a couple bucks.

2. Valve adjustment is very important. Check it/do it.

3. So are glow plugs. There's a slightly more expensive version of the pencil glow plugs which fit into the larger holes on the older heads.

4. make sure you have a battery that is up to snuff, though I will say that a battery that is weak will start the car if it is not frozen cold.

5. Synthetic or even a blend helps too.

6. Have you checked the block heater plug? Do you have a plug but no cord? That's what happened to me and 14.00 fixed that problem!

Your starting problem, unless involving something more serious, is not expensive, seemingly, and relates more to maintenance than to potential expense.

caramel240d · #5 01-12-2011, 11:05 AM

New development, when I turn it over, quite a lot of grey/white smoke comes out of the exhaust pipe. ?????

strelnik, thanks for the tips. I'll check those lines but we can rule out air leaks right? Unless it's a huge leak but the pump squeaks meaning the lines are full...

I'm just trying to save a little money.. hopefully it's not the valves 'cause that's about $150 right?

I'll try to find the block heater, and I suppose I need to break out the multimeter to check the glow plugs.

Thanks for allaying my fears.

charmalu · #6 01-12-2011, 11:54 AM

If you have a shop do your Valve adjustment, expect an hours labor plus enviro fee, VC gasket etc....

You can do this your self, not all that difficult. first time might be a little scarry, but after a few times you will breeze right through it. It needs to be done every 15k or once a year. just before winter is the best time.

here is a link that will help you.

http://www.peachparts.com/shopforum/showthread.php?t=107729

At the top right of the page is the resources Tab, there are Links to about every possible thing you can imagine to do on these cars. and also in the DIY Articles, is pictures of how to do it jobs member have posted.

Your 80 240 should have the small pencil Glow plugs. think it is the first year for them. at least my 80 has them.

Charlie

Welcome to the forum, hope to see you hanging around here for a long time.

#7 01-12-2011, 12:01 PM

Before you do anything else, take a close look for fuel leaks where you replaced the filters. A small leak will allow air to accumulate in the fuel system after it's been sitting for a couple of hours. My 240D did the same thing a couple of weeks ago because the bolt on the large filter wasn't tight enough causing a small leak.

If it's due for a valve adjustment, have that done too.

Stevo · #8 01-12-2011, 12:09 PM

Quote:

Originally Posted by caramel240d

I'm just trying to save a little money.. hopefully it's not the valves 'cause that's about $150 right?

A 240D is about the easiest car to work on that you could ever find these days. but if your not willing too do a simple job like adjusting the valves or swapping in upgraded glow plugs your going to pay through the nose for someone else to do it. Not to mention how difficult it is to find someone that actually wont screw it up. Take that $150, buy a set of valve adjusting wrenches, a mighty Vac (to work on your vacuum system) and do it your self. All the info is right here on this forum. Its really not hard to do most jobs that need to be done too keep these cars going, epically the 240D.

#9 01-12-2011, 12:14 PM

Quote:

Originally Posted by Stevo

A 240D is about the easiest car to work on that you could ever find these days. but if your not willing too do a simple job like adjusting the valves or swapping in upgraded glow plugs your going to pay through the nose for someone else to do it. Not to mention how difficult it is to find someone that actually wont screw it up. Take that $150, buy a set of valve adjusting wrenches, a mighty Vac (to work on your vacuum system) and do it your self. All the info is right here on this forum. Its really not hard to do most jobs that need to be done too keep these cars going, epically the 240D.

I agree, the 240D is very easy to work on; however, I still let my indy do the valves because it's worth the cost not to have to spend an hour messing around with them. It's just the old time/money trade-off. If you do bring it to a shop, make sure they actually know what they're doing.

charmalu · #10 01-12-2011, 01:56 PM

CAREMEL240d, where are you located? add your location, maybe someone lives near you that can give you a hand. better to do things your self, and learn as you go, than pay some Dufus mechanic that may be learning on Your car.

Charlie

leathermang · #11 01-12-2011, 02:10 PM

Good answers in this post..

One thing many do not know... only if you read the FSM or see it here.. is that the glowplugs keep getting hotter up to about 60 seconds of ' ON '....
So since this is winter... try timing your glow cycle.. do not turn it on and back on.. just leave it on 45 seconds and see if that helps... my wagon a few years ago got balky at 50 degree F... crazy... but 30 seconds of glow and it had no problem starting.. it also sat 18 months before I sold it... and the guy only put a batter to it and it started right up...... OCD me would have replaced the fuel, filters, oil ...... first.... and it started within 3 seconds...... no one was more surprised than I was... it had suspension problems and no AC or I would not have sold it...
Anyway, I am saying that sitting per se is not a problem.....

caramel240d · #12 01-12-2011, 03:37 PM

Wow thank you all for the help! What a great community here.

I'll definitely look into adjusting the valves myself-- it looks scary haha. I didn't know it was something that could be done DIY. I'd love to be able to do it myself.

I'll check for air leaks again and also try warming the glow plugs longer, checking their voltage, the battery voltage, and check the block heater.

charmalu, good idea, I'm in Melbourne, Florida. I'll add it to my profile.

Is the grey/white exhaust smoke normal when trying to start?

Thanks everyone!!

#13 01-12-2011, 03:41 PM

After a few tries you will have a bunch of fuel in the cylinders, some smoke is to be expected.

79Mercy · #14 01-12-2011, 05:19 PM

Which type glow plugs do you have? Im gonna bet you have the new pencil plugs since your GP light only stays on for 5 seconds.

So first you need to pull all GP's and test them, apply 12V + to the threaded stud, and ground it via the body of the GP where it screws into the head..

Than you need to order a valve cover gasket and do a valve adjustment like other have said. You don't need the bent wrenches, you have use 2 14mm wrenchs, i like using the ones that come in the original factory tool kit. Then just pick up a set of feeler gauges. http://dieselgiant.com/valveadjustment.htm

caramel240d · #15 01-13-2011, 05:53 PM

OK there's a large diesel stain underneath the front passenger side. If you're facing the right side of the car, it's about one foot left of the front right tire and 1-2 feet back. Is this from when I let fuel come out of the banjo bolt? If that's true it would have had to somehow travel from the secondary canister filter all the way 2-3 feet away left and back. Otherwise, what is this?! I moved the car to see if there will be a new leak.

Battery is at 12.45v, the glow plugs ohms are all over the place when I connect from battery neg. to each pin on the large connector (http://www.dieselgiant.com/glowplugrepair.htm). Haven't check the glow plugs themselves, but that's pretty indicative of a problem, no? The car should start in warm weather without functional glow plugs, correct?

How do I loosen the nuts at the injectors?? I'm not very tool handy. A crescent wrench is definitely not doing the job. It's the larger lower one right?

Is there another way to see if the injection pump is pushing fuel to the injectors? The lift pump works since fuel leaks out of the secondary canister filter when I loosen the bolt... but maybe the IP is dead?

I'm going to try the WD-40 trick-- can I just take the metal top off the air intake and spray the WD-40 into the hole, or do I need to unmount the whole air filter encasing?

Also, does anyone know where to find an engine diagram with labels or explanations? I'm confused about the lines and their directions.