Intermittent Problem Puzzle

[mdsalemi]

Hey Guys,

Presently my car is "laid up" at the mechanics; it was towed there the other day.  It died in a construction zone and it was a solid 1/2 day debacle to deal with getting it out of traffic, towed, and getting home.  I don't want to do that again.  Not only is it frightening, it is downright unsafe: I was dead, blocking an intersection, surrounded by 40 wheel, 60 ton gravel haulers.  The only thing good about it was it was a sunny day.  Literally there is nowhere to go in Michigan at the moment w/o hitting a construction zone; I don't knowingly go through them.  They pop up all over all the time; in fact in this situation, there was a "construction zone on the highway" that I was avoiding when I ran into another one on the detour!   Once towed and dropped at the mechanics it started and ran fine, of course.[!]

It has a recurring, intermittent problem with "dying" on the road.  The dying has exhibited characteristics of both no spark/bad ignition; or no fuel.  Suspected culprits are the Crane XR700 module; fuel pump, coil, even the ignition switch; to a lesser extent, wiring harness, and something else I'm forgetting about in my concern.  Darn near everything else was renewed in the restoration, so I don't think the injection pump is a problem, and Dr. Benz "renewed" the distributor in 2004, finding a couple of missing little parts.  I've been on the phone with Crane Tech support, and we did find some voltage issues since corrected (bad ballast resistor); clearly they had nothing to do with the problem.

Problem is there's nothing to check!  In the shop, in my garage, the car will always start and run well.  When it is running, most of the time, it runs in an enviably fine way.  Super smooth idle, strong acceleration.  After some unknown period of time not specifically related to operating or ambient temperature, it just dies.  Sometimes it will easily restart; other times not at all.  It always cranks well. These dying incidents: it did it in January after 20 miles at 45MPH at 50 degrees; and it did it the other day after 8 miles at 60MPH and 70 degrees; and the week before after 30 miles at 65 degrees at 70MPH.

Even if I had some test equipment, it would have been extremely unlikely to have checked the fuel pump pressure and volume while stuck on the road.

Despite the great cost, my inclination is to buck the scientific method and simply brute force change the aforementioned items because I can't duplicate the problem; the only way I can see to duplicate the problem might very well put me; my mechanic; or the car in serious harm's way.  If the brute force method doesn't cure it at least the problem has seriously been narrowed down.

My mechanic is at as much of a loss as I am; you can't fix what isn't broken.

Any insights would be appreciated, I've run out of ideas, but I do know that something must be done because the problem won't fix itself.

Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[jeffc280sl]

Had a similar problem with a Jeep and my 280SL with a Crane ignition module.  In both cases the cause of the problem was spark plug/coil/distributor wire connections.  The problem was unpredictable and sudden.  Sometimes it would restart and sometimes it wouldn't.  Some of the brass? connector plugs on the plug/coil/distributor wires has some sort of whitish powder on them.  I assume this was created because of a poor connection and some sort of arcing.  Anyway a good cleaning of all components and a small adjustment to some of the brass connector plugs seems to have fixed the problem.  Everything has been fine for the last month.

Jeff C.
1970 280SL 4-speed

[ted280sl]

Mike,
  I don't know alot about the micro switch on the firewall but, I understand that it will kill the engine if it is not working. Just a thought.
Regards,
Ted

[Naj ✝︎]

Also check the 3 pin connector (both ends) - Crane box to distributor. The wires are just crimped, not soldered to the pins and may have worked loose/corroded slightly.

naj

65 230SL
68 280SL

[RBurg]

Michael: After you clean the connections (suggested by Jeff) one could use a silcon grease (very light coat)which is used by electricans  for good contact and prevent arching in high voltage  conecations which give very good contact.

Another thing you could pack any discarded spark plug. When it fails pull the plug wire and use the sprae plug and ground it to any part on the engine - turn it over and see it there is spark!
Good Luck

Ron - Minnesota
71 280SL Tobacco "O GIGI"
97 E420 Silver Mist

[Ricardo]

Hi Michael
Sorry to hear of those kinds of break downs...not that there are good times to have glitches, but in traffic surrounded by trucks has to be the worst possible....glad you escaped
I had a similar situation for nigh on two years, though more often it was a restart problem after shutting off to re-fuel or for only a few minutes.....it wouldn't restart for sometimes half an hour and then it would be fine for days or weeks...I tried many things and consulted regularly with Dan...redid the head, chain, tensioner,  inj. pump rebuild, fuel tests, tank cleaning.....a long list of maybe's......I'm fairly certain the ultimate repair was dumping the Crane (the second replacement from them) after Dan said to me one time why he didn't like electronic ignition systems in general..."what are you going to do when it fails, you can't fix it"
I knew the PO had switched to the Crane because his mechanic had told him the dist. was worn...I got an exchange rebuilt dist. from Dan and have forgotten I ever had that starting problem....plus my car runs great from doing all those other things [:p]
It's pretty in-expensive to try using points again....
I carry an extra set of points in my road kit, in case
Hope that helps Michael

[mdsalemi]

Hey Guys, thanks for some advise...as a response to some:

1)  I always use Dow Corning 4 Dielectric Grease.  My Dad taught me well.

2)  Molex connector pins are soldered; I did it myself when I renewed the ballast because I don't like crimps.

3)  All Crane connections are re-crimped w/new ends and soldered.  I don't like crimps.

4)  It could very well be the Crane module; and as one keeps spare points one should keep a spare module around.  Sadly, the one I ordered as a spare about 10 days ago won't be here until Friday.  It's a 5 minute install, then a little longer of course to determine if that was the problem, and then some more time to harden the connections (i.e. solder, etc. and route the wires properly)...I've replaced more sets of points in my day then electronic parts.

5)  All switches on the firewall and all relays in the engine bay are relatively new (2002)

6)  Plugs, wires, cap, etc. are all new-2004.  No whitish powder, all connections cleaned last week, but all were pretty clean anyway.

Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[Cees Klumper]

Michael - for what it's worth, I would suspect wire/electrical connections with those symptoms. I would go for renewing all ignition wiring, the Crane module, and the spark plugs and leads. Maybe your ignition switch or the associated wiring? Very frustrating situation to say the least!

Cees ("Case") Klumper in Amsterdam
'69 white 280 SL automatic

[71 pagoda]

Had a similar problem. It ended up being the screen in the fuel pump had dirt clogging it. After the car sat for about 45 min it would start right up, The dirt would settle to the bottom of the screen letting the fuel thru.  I ended up replacing the whole 35 year old  pump. Never had a problem after that.

[ChrisInNashville]

Ditto on that.   I had the exact same sequence of symptoms last year and it was a very minor amount of debris in the fuel.  Remember, I'm not mechanical;   I hope you get it fixed soon.

[mdsalemi]

Guys,

Sadly, (and yes, unbelievably) you've received the short version.

4 weeks ago tank was drained, and the entire fuel system gone through--screen cleaned, new filter etc.  Yes at the tank/pickup and fuel feed pump and injection pump.  Fuel tank is new, installed last year.  All hoses and lines replaced not too long ago...Car ran about 2,000 miles after tank was installed last year without issue, THEN all the cleaning above was done this year again.

Have not ruled out the 35 year old fuel feed pump, but if it is the problem it probably isn't accumulated debris; between Dr. Benz in 2004, the new fuel tank in 2005, and the cleaning a few weeks ago, I suspect my fuel system has had more cleaning then most.

Other possibilities thrown at me recently are the ignition switch being flaky (Joe and Cees) but I think we might be able to duplicate that by wiggling (we're not); the fuel shutoff solenoid failing in the shutoff position (rare but it has happened, I'm told)

The most obvious to check is the Crane module and the new one comes today.

Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[JimVillers]

Michael .... I also had Crane ignition problems.  With several members responding with similar stories, why put a new Crane unit back in your car.  I switched to points fro a while and then switched to Pertronix.  The beauty of the Pertornix is that it dropped right in without even needing to change the ignition timing.  Of course, I still carry a spare set of points in the car "just in case".

Jim Villers
190SL, 230SL 5-Speed, 190E 2.3-16 Kompressor

[mdsalemi]

quote:Originally posted by JimVillers

Michael .... I also had Crane ignition problems.  With several members responding with similar stories, why put a new Crane unit back in your car.  I switched to points fro a while and then switched to Pertronix.  The beauty of the Pertornix is that it dropped right in without even needing to change the ignition timing.  Of course, I still carry a spare set of points in the car "just in case".

Jim Villers
190SL, 230SL 5-Speed, 190E 2.3-16 Kompressor

The answer is quite simple: installing the new Crane module literally will take 5 minutes.  One Molex connector, Coil +, -, and ground.  If that's the problem, hopefully I'll know within the first 20 miles or so.  Remember the distributor is already modified with the pickup.  Re-read the posts: I have not heard too many stories yet of a failure of the Crain module.  We've had fuel issues and connector issues and grounding issues, microswitches, etc. and one by one we've gone through these things without finding a root cause.  The ONLY reason I have not been able to check/change the Crane yet is due to their "distributors"--the companies that sell them, not the one on the car!!  Lots of people list them for sale, few stock them.  Some were backordered.  I ordered from someone who said they could ship in 24 hours that turned to 10 days.  The ONLY reason why I have not gone back to points is that there is a non-trivial task in removing the Crane pickup inside of the distributor and replacing with points; if it turned out NOT to be the issue (say it was the fuel feed or ignition switch) I just undid something senselessly to which going back would again be non-trivial.  Also, I am working with Crane Tech Support and we did find some voltage issues, it warranted correcting them before simply removing the unit.  Crane Tech Support offered to replace the out of warranty items if they are the cause.

By posting here, perhaps somebody had/has an idea that we have not thought of.  In all my fuel problems last year and the year before, nobody [from this list at least!] suggested that the fuel tank needed replacing.  One mechanic here in Michigan did (apprenticed at Sindelfingen for what its worth!!) with 99% certainty.  My fuel issues went away with the new tank--before the new tank I had to have > 1/2 tank of fuel at all times.  Once the new tank was in the problem went away.  Yesterday someone suggested off line to disconnect the fuel shutoff solenoid.  When I get the Crane module in today we'll do that.

I listen to everyone, and certainly have not ruled out your experiences, removing the Crane, going back to points, or changing to a Pertronix, but if 5 minutes with the new Crane module will tell me something, perhaps we should do that first.  There is nothing inherently wrong with the Crane, either in theory, practice or even on my car.  It was installed over 5 years ago and presumably has worked well since then, barring today's problems.

It is interesting that there are some out there who dismiss all the electronic ignition systems.  It is interesting to point out though, the every single car sold in the USA, probably most in the world today has electronic ignition!  Breaker points have gone away, and for good reason.

Bottom line?  New Crane box goes in on Tueday, fuel shutoff solenoid disconnected, and we'll see from there.  Mechanic was told to do the fuel pressure/volume check; the feed pump is original.

Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[JimVillers]

Michael .... If this Crane usnit fails, let me know as I have a couple of new spares that I would be glad to send to you.  Reinstalling points should be trivial unsless the distributor was modified (I did not motify my distributor when I installed my Crane unit).  The Pentronix should just bolt in with or without the point post so that should be trivial in any case.

Yes, every modern car has electronic ignition ..... but I am not aware or any with an optical triggering system; all utilize a Hall magnetic trigger located on the flywheel or somplace else.

I hoe that your new unit provides a lasting solution.

Jim Villers
190SL, 230SL 5-Speed, 190E 2.3-16 Kompressor

[mdsalemi]

quote:Originally posted by JimVillers

Michael .... If this Crane usnit fails, let me know as I have a couple of new spares that I would be glad to send to you.  Reinstalling points should be trivial unsless the distributor was modified (I did not motify my distributor when I installed my Crane unit).  The Pentronix should just bolt in with or without the point post so that should be trivial in any case.

Yes, every modern car has electronic ignition ..... but I am not aware or any with an optical triggering system; all utilize a Hall magnetic trigger located on the flywheel or somplace else.

I hoe that your new unit provides a lasting solution.

Jim Villers
190SL, 230SL 5-Speed, 190E 2.3-16 Kompressor

The Crane was installed by my restorer way back when, and it looks like there's either a hole in the distributor for the wire to come through (that's what I meant when I said modified), or perhaps this is where the insulator fits from a set of points...can't really tell at the moment w/o another one side by side.  In any case it looks like there's some sealant there.

You might have been lucky with the Pertronix; there are others on the list who have had some issues in getting it installed, and getting it to work for some reason; why I can't tell you.  Your experience is what everyone hopes for!


Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[JimVillers]

Michael ... Yes, the hole in the distributor is for the post that connectes the points to the outside connector.  Here is a good link to see what the Bosch internals look like:
http://www.glenn-ring.com/010/

Jim Villers
190SL, 230SL 5-Speed, 190E 2.3-16 Kompressor

[JPMOSE]

The microswitch on the firewall is part of the emissions on a USA version -- in conjuction with the fuel shutoff solenoid, speed sensor, oil pressure switch on the transmission and relay.  Erratic behavior of speed sensor will cause stalling at lower RPMs in 3rd or 4th gear.  I would definately suggest disconnecting the wire on the fuel shutoff solenoid if you haven't solved the problem by other means.  The fuel shutoff solenoid is the lower one on the back of the injection pump.

Years ago, I had erratic stalling on my 1969 Lincoln Continental and it turned out the be the Mallory Electronic Ignition kit that I installed.  Great product, but after 75k miles of use it was failing.  Like your symptions, the car would suddenly start miss and eventually stall.  Once it cooled down, the car would run beautifully for a while and then suddenly die (which happened to me in a busy intersection in Beverly Hills back in the late 1970's).  Hence, I would definately consider the Crane system as suspect!

Good luck Michael.

Best Regards,

J. P. Mose
1968 250SL
1987 560SL

[mdsalemi]

Thanks, JP.  It's the weekend and I'll have to wait until Tuesday to check that solenoid wire.  Jim and I, and you too, are suspect of the Crane box.  Who know it would take so long to get another one!  I ordered two weeks ago.  Was supposed to be here TODAY.  Well, UPS has come and gone.  Me?  I'm going up north, forgetting about cars for a couple of days and get on the water in a boat!

Jim, one of the cardinal rules of installing any electronic ignition system is that your ignition must be working properly FIRST.  Since I have not established that with certainty...understand my hesitation in changing to another brand so quickly!!

Thanks for the photo set; I have the -050 distributor, but it looks like from the photos that they routed the wires through the large hole 180 degrees behind the Bosch label, and filled with RTV.  So, it has probably NOT been that modified to accomodate the Crane optical sensor.  Just an illusion.

Have a nice weekend everyone!

Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[ja17]

Hello again Michael,

I am in agreement that the fuel shut off solenoid or its system could be your problem. You may just want to disconnect it for the time and see if the problem goes away. You can also hook up a test light to the solenoid to see if it activates at the wrong time.

Joe Alexander
Blacklick, Ohio

[TheEngineer]

Mike: There was a evil spirit that came thru town a while ago: My lil' ol' red car quit downtown Seattle on a steep hill in rush hour traffic at 5:30PM. Had to roll backwards onto sidewalk. Got a jump and lil'red car ran for about one block. Battery was so dead, as soon as engine went to idle, voltage dropped to insufficient. It was also time to run with lights. Parked again on sidewalk, called neighbor to drive me to Costco, bought new battery, installed it. Car started and has run fine ever since. It's the perverse behaviour of inanimate objects! Good News is: Seattle cops were very nice!

'69 280SL,Signal Red,113044-12-007537,tired engineer, West-Seattle,WA

[Ben]

quote:Mike: There was a evil spirit that came thru town a while ago: My lil' ol' red car quit downtown Seattle on a steep hill in rush hour traffic at 5:30PM. Had to roll backwards onto sidewalk. Got a jump and lil'red car ran for about one block. Battery was so dead, as soon as engine went to idle, voltage dropped to insufficient. It was also time to run with lights. Parked again on sidewalk, called neighbor to drive me to Costco, bought new battery, installed it. Car started and has run fine ever since. It's the perverse behaviour of inanimate objects! Good News is: Seattle cops were very nice

...............I had exactly the same problem last October, using lights and heater !

New battery and that was it ! The only other comment I would make is for the sake of investigations, in order to find the root, that you dont fit the new Crane AND disconnect the solenoid at the same time. Otherwise you will never know for sure the exact cause. hook up the test lamp as Joe suggested !

Good luck !

Regards,
Ben in Ireland.
'64 230SL 4sp.

[mdsalemi]

Update 5/31:

Finally the new Crane ignition module arrived and was installed.  The wire to the lower (fuel shutoff) solenoid was removed.

Problem still happened; died at about 20 minutes out and thankfully a few minutes from home.  So at first glance it isn't the Crane ignition box and isn't a faulty fuel solenoid.

A new fuel feed pump is on order.

Got the parts to build a few test lamps; per Pete's suggestion they'll be hanging on the windscreen wipers and visible from driver's position while running.  One will connect between coil minus - to ground and tell me when the coil is firing; will help determine if the optical module in the distributor is the issue and if the coil is being told to fire.

Still have a coil to swap in too.

Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[JPMOSE]

Any new developments over the weekend Michael?

Best Regards,

J. P. Mose
1968 250SL
1987 560SL