non running 280SL

[dseretakis]

Its been over one and a half years now that my 280 SL will not run.  It started when I was driving home and the car just stalled and would not restart.  I pushed it into the garage of my apartment building where it has sat eversince.  I figured it was probably ignition related as there was fuel coming from the fuel line going to the intake manifold when I disconnected the line.  I did not however measure the rate of flow.  I proceeded then to replace the points, rotor, cap, condenser, wires, plugs and got the car to start, run poorly from anywhere from 15 secs to up to 2 minutes and then stall again.  I gave up and left the car that way for 1.5 years.   I figured that maybe the ignition coil was bad so I replaced it today.  Again no change.  It runs poorly for 30 secs to a couple of minutes while giving it a good amount of gas and then stalls.  I'm at a loss.  I don't wan't to just keep replacing parts.  I'm starting to suspect the fuel system again.  Any ideas? Thanks,
Dimitri

[ja17]

Hello Dimitri,

I remember you posting about a year and a half ago.  Don't get discouraged, a little persistence will pay off!

If you have a fuel tank (flower pot) problem, often times adding fuel to raise the level in the tank will temporarily solve the running problem. If your fuel level is below one half, try adding at least 5 gallons of fuel.

Joe Alexander
Blacklick, Ohio

[rogerh113]

Hello,

I had a similar problem with regards to stalling recently, and it did turn out to be the fuel pump.  My car stalled primarily at idle, but ran at speed.  I would not have guessed at the fuel pump from the symptoms.  There is a fuel line connection at the driver's side engine mount, which you can detach and check the flow.  I know that other posts list how to measure it and the expected amount, but the flow rate is substantial.  Replacement fuel pumps are indeed expensive, so I would suggest getting the prior post data and measuring the flow (pretty easy).  Also, if you don't hear the fuel pump ticking when you first turn on the ignition, it probably isn't too healthy.

Good luck, and the car's are worth getting running - you won't find better fun anywhere (with regards to a car)!!

Regards -- Roger

[dseretakis]

quote:Originally posted by ja17

Hello Dimitri,

I remember you posting about a year and a half ago.  Don't get discouraged, a little persistence will pay off!

If you have a fuel tank (flower pot) problem, often times adding fuel to raise the level in the tank will temporarily solve the running problem. If your fuel level is below one half, try adding at least 5 gallons of fuel.

Joe Alexander
Blacklick, Ohio

I think that the fuel level is above one half but then again the fuel gauge has never been that accurate.  I'll try adding some more fuel and see what happens.  I was however under the impression that fuel entered the flower pot from the bottom so I'm not clear on adding more fuel would help unless it also enters from the top of the pot.
Dimitri

[J. Huber]

In addition to Joe and Roger's input, I'd be inclined to go back to Pagoda 101: take a another look at the dwell and timing, then make sure the linkage is set correctly. I'd also confirm the CSV isn't leaking. Then I'd check the vacuum and see if I could get a steady idle.



James
63 230SL

[dseretakis]

quote:Originally posted by J. Huber

In addition to Joe and Roger's input, I'd be inclined to go back to Pagoda 101: take a another look at the dwell and timing, then make sure the linkage is set correctly. I'd also confirm the CSV isn't leaking. Then I'd check the vacuum and see if I could get a steady idle.



James
63 230SL

How do I check for a leaking cold start valve?  I can't check dwell and timing because I really can't get the thing to run.  It barely runs for a maximum of 1-2 minutes with constant easing off and pushing down on gas pedal.

[ja17]

Hello Dimitri,

The flower pot is open at the top. When the fuel level is high fuel will simply flow into the flower pot from the top. So even if the small opening at the bottom is cloged, your car would run when the fuel level is high.

Joe Alexander
Blacklick, Ohio

[doitwright]

You do not need for the car to run to set the dwell.  You just need to be able to crank the engine.  You should also check your compression just to eliminate the possibility of a broken valve.  Remove the fuel pump fuse when doing these checks and settings.  Final timing adjustment can be done after you get the engine running.  The dwell setting has a huge impact on how well the car will run.  Research the topic on this site and you will find plenty of tips.

Frank Koronkiewicz
Willowbrook, Illinois

1970 280SL Light Ivory

[seattle_Jerry]

Draining the gas tank and putting in fresh gas would be helpful too.

Plus you can check it for rust chunks in the gas that could be inhibiting flow.

1967 230SL Havana Brown Auto with A/C

[dseretakis]

quote:Originally posted by doitwright

You do not need for the car to run to set the dwell.  You just need to be able to crank the engine.  You should also check your compression just to eliminate the possibility of a broken valve.  Remove the fuel pump fuse when doing these checks and settings.  Final timing adjustment can be done after you get the engine running.  The dwell setting has a huge impact on how well the car will run.  Research the topic on this site and you will find plenty of tips.

Frank Koronkiewicz
Willowbrook, Illinois

1970 280SL Light Ivory

Please forgive my ignorance, but do I even have to have the car running to measure dwell?  My understanding of how these things work is that they read the time that the points remain closed.  If the engine is not cranking then it should not work.  My dwell meter is reading in the 30s without cranking the engine.  The point gap is set at .012.  When I crank the engine the dwell reads about 15.  This doesn't make any sense to me unless the dwell meter is at fault.  It is a very old Snap-On model that I've never used before.  

Dimitri

[J. Huber]

Hey Dimitri, no such thing as ignorance here...(or I'd be in big trouble!)

That was a good question -- so I just tested my dwell meter not running and running. Not: 60  Running: 37.5. (a bit low for my liking but car is running fine)... So I'd say yes the car has to be running/cranking to get an accurate dwell reading.

This would also lead me to believe that if you are getting the 30/15 reading, something is amiss with your point gap and/or dwell. Also, I think the gap is generally closer to .016 -- which might make a difference.

PS to check Cold Start Valve. The CSV is located on the intake manifold -- there is a 7mm test screw. Remove it, place a towel underneath, and turn ignition to run, not crank, just so your hear fuel pump whining. Watch the screw hole -- you should not see any fuel coming out. I am not sure a leaky valve would cause the car to not run but it is one of the basic things to check to get things right.

James
63 230SL

[dseretakis]

Hi James, I actually went to Sears tonight and bought a new dwell/tach meter.  I'll check it out tomorrow and report back.  Incidentally I'm checking the dwell directly from the clip to where the points are attached in the distributor as suggested by other members on this forum.

Dimitri

[dseretakis]

Ok, so my old dwell meter was defective.  The new one reads 38 with a point gap of .012.  It reads 30 with a gap of .016.  Car will still not run though.  I'll try adding some more fuel and see.

Dimitri

[J. Huber]

Hi Dimitri, well I'd say the dwell at 38 is what counts (the gap is secondary)... It was probably worth double checking though -- mine basically wouldn't run when the dwell was too far off. A fuel delivery/possible debris in that small flowerpot line might be the culprit. Keep us posted...

James
63 230SL

[dseretakis]

Well, the fuel tank is pretty much full with 2 more gallons added but no change.  The car starts and seems to run on just a few cylinders, as time goes by a few more cylinders kick in but it continues to run rough and shake.  It smooths out a little if I give it a liitle more gas.  If I let go of the gas at any point or give it too much gas, the car will stall.  It puts out a decent amount of grey/white smoke.  There is no oil in the coolant or vice versa.  I don't have a gasoline engine compression tester but this might have to be my next purchase.

Dimitri

[dseretakis]

Haven't gotten around to compression test yet, but was wonering about the coil and ballast resistors.  I've been doing some reading about them on this forum and have just been left confused. By the way the car is a 71. I replaced mine which was red with a black one - that was supplied to me by BuyMBParts.  I didn't realize that there were any options.  As far as ballast resistors go should they be changed with the coil as well?

Dimitri

[J. Huber]

Hey Dimitri. It's always been my understanding that the best set-up for our cars is the red coil (which is actually silver now w/ a red sticker) and the 1.8 ohm resistor. Most bang for the buck. I'd say its a good idea to change the resistor at same time. Both should last a long time though.

James
63 230SL

[Peter van Es]

Check this topic in the technical manual...

http://www.sl113.org/wiki/pmwiki.php?n=Electrical.Distributor

Peter


Also known as 'admin@sl113.org' and organiser of the Technical Manual (http://www.sl113.org/wiki/pmwiki.php). Check out http://bali.esweb.nl for photographs of classic car events and my 1970 280SL.

[dseretakis]

quote:Originally posted by J. Huber

Hey Dimitri. It's always been my understanding that the best set-up for our cars is the red coil (which is actually silver now w/ a red sticker) and the 1.8 ohm resistor. Most bang for the buck. I'd say its a good idea to change the resistor at same time. Both should last a long time though.

James
63 230SL

Hi James.  The coil I have has a silver body with red stickers and a black bakelite or whatever material on the top.  Is this the one that you are referring to?  My old coil had the red bakelite material on top.

Dimitri

[dseretakis]

Upon further observation, my new coil is silver with black top and yellow stickers with one yellow and red sticker.  Part # on box is 221 122 001.  My old coil has blue body with red top.  Rusty at buy mb parts has 2 ballast resistors listed on his online catalog a 0.4 and 0.6 ohm one.

Dimitri

[J. Huber]

Well, my coil reads 0 221 119 030. I believe the resistors come in .04, .06, .08, and 1.8. Some simply add to whatever was originally on the car (for example, my 230s had a black coil with a .09, so I could have added a .09) -- but it is easier and cleaner looking to have just the one. You might try Miller's or Ray at Bud's Benz. They should have all the varieties...

James
63 230SL

[Naj ✝︎]

quote:Originally posted by dseretakis

Upon further observation, my new coil is silver with black top and yellow stickers with one yellow and red sticker.  Part # on box is 221 122 001.  My old coil has blue body with red top.  Rusty at buy mb parts has 2 ballast resistors listed on his online catalog a 0.4 and 0.6 ohm one.

Dimitri

Hello Dimitri,

Your coil is for the transistorised ignition system that uses both 0.4 and 0.6 ohm ballast resistors. Do you have the unit under the battery?

Here's a file with some details you can check:

http://www.sl113.org/forums/uploaded/jeffc280sl/15-20B.pdf

Hope this helps

naj

68 280SL

[J. Huber]

Nice save Naj. Dimitri, I may have been leading you down the wrong path on the Bosch coils -- as I was assuming non-transistorized. I sincerely apologize.

James
63 230SL

[dseretakis]

Thanks everyone for your input.  I'll be away from my car for a few weeks.  I'll resume the diagnostics then and bombard you with more questions!  

Dimitri

[dseretakis]

Hi all.  It's been a while since I've been able to get back to working on my 71 280SL which stalled out on me almost 2 years ago.  I haven't been able to get it to start/run since then.  At best it'll barely start and run roughly for a minute and then stall again.  I have replaced most ignition components, coil, plugs, wires, condenser, cap, rotor to no avail.  I have not measured the rate of flow from fuel pump but fuel does flow quite freely when I disconnect the fuel line at the CSV.  I have not checked flow at the return line.  I have topped of the tank with fresh fuel but that doesn't help.  The car is in an apartment building garage so I haven't really been able to do much with the fuel tank.  The last thing I was going to do when I last posted on this topic was check compression.  Well, I did that today.  The test was done on a cold engine since I can't start it to warm it up.  The values are as follows: Cylinder #s 4,2,6,3,5,1 197, 199, 201, 199, 201, 200 respectively.  Looks like the engine is pretty tight.  
One other thing I noticed is that the .4 Ohm ballast resistor is in bad shape - cracked with a small piece or two missing.  The other .6 omn resistor looks fine.  Could a faulty ballast resistor cause a
hard starting/ non-running condition?
Dimitri