Topklasse Discussion Board  
Home Forum Legal/Privacy Media/Picture Gallery Websites and Links Technical

Go Back   Topklasse Discussion Board > THE CRAFTSMAN - TECHNICAL DEPARTMENT > MECHANICALS

MECHANICALS With a 30 year-old automobile, there will always be discussion here - maintenance, modifications and mechanicals.

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 11th October 2009, 07:41 PM
450SE's Avatar
450SE 450SE is offline
Aficionado
 
Join Date: Mar 2009
Location: Melbourne, Australia
Posts: 187
Default Help required - engine cutting out

I've got some sort of issue which appeared Friday night on the 450SE.

For some reason the motor cuts out for a split second while cruising along, giving a surge sensation when cutting back in. At idle (in Drive - say at a set of traffic lights) the miss hits at the wrong time & the engine dies a quick death. It restarts easily enough, but as the motor died on me half way into a major roundabout yesterday (), I figured it's best to let the car rest!

The miss occurs when the engine is stone cold & also at temperature.
One incidental thing that I noticed the first time it happened is that the rev counter flew into the red zone momentarily when the miss occured although the revs did not increase. (I thought at the time that I was just imagining what I'd seen & the miss was a result of not paying attention to my foot).
I've tried driving with the air conditioner, fan & radio off thinking it could be a problem of lack of power. No difference.
The car has just had a brand new battery fitted.
It is also *slightly* slower to start up initially at the moment (say one extra crank of the engine).
All the leads to the distributor & plugs are firmly in place.

I went to my mechanic Saturday morning who took a quick look at it & short of adjusting the idle speed up a tad, said that I'd need to come back Monday as he was flat out. The idle adjustment didn't fix the problem... It will go into the shop tomorrow with hopefully an easy, minor repair... whatever it is...

Has anybody experienced this before or does anybody have any suggestions as to what it may possibly be?
__________________
Valium. Helping me get through the day since the 1980's.
Reply With Quote
  #2  
Old 11th October 2009, 08:46 PM
WGB's Avatar
WGB WGB is offline
Aristocrat
 
Join Date: Feb 2008
Location: Perth Western Australia
Posts: 1,285
Default Re: Help required - engine cutting out

If it has recently been fitted with a new battery make sure no earth connections have been damaged.

Best of luck - let us know what the mechanic finds.

Bill
Reply With Quote
  #3  
Old 12th October 2009, 01:12 AM
TJ 450's Avatar
TJ 450 TJ 450 is offline
Aficionado
 
Join Date: Mar 2008
Location: Perth, WA, Australia
Posts: 360
Default Re: Help required - engine cutting out

It will be an electrical problem of some sort, most likely relating to the ignition system or simply a bad connection as Bill suggests. The tachometer gets its input directly from the coil, so I would be looking at the wiring or all of the parts in that system before and including the coil for possible faults.

If it was a charging problem, it would flatten the battery and cause more widespread malfunctions.

Good luck.

Tim
__________________
1976 450SEL 6.9
1988 560SEL, Hydropneumatic, 220KW Euro.

Last edited by TJ 450; 12th October 2009 at 01:14 AM.
Reply With Quote
  #4  
Old 12th October 2009, 06:49 AM
BenzBoy BenzBoy is offline
Noble
 
Join Date: Feb 2008
Location: Sydney - Centre of Civilisation
Posts: 6,813
Default Re: Help required - engine cutting out

The only times I have experienced what you have listed has been a semi-broken and corroded electrical conection which was only successfully diagnosed when it completely failed. I agree it is probably electrical - main feed to the engine or an earth along the way.
Regards,
Benz-Boy
Reply With Quote
  #5  
Old 12th October 2009, 07:22 AM
John S John S is offline
Connoisseur
 
Join Date: Feb 2008
Location: Sydney
Posts: 639
Default Re: Help required - engine cutting out

When was your fuel filter last replaced?
Reply With Quote
  #6  
Old 12th October 2009, 02:47 PM
SEL_69L's Avatar
SEL_69L SEL_69L is offline
Aristocrat
 
Join Date: Feb 2009
Location: Sydney, NSW, Australia
Posts: 1,313
Default Re: Help required - engine cutting out

Fuel pump or fuel pump relay? Have a look at my long post, page 2 on the string "6.9 Turn the key then....."

Last edited by SEL_69L; 12th October 2009 at 02:51 PM.
Reply With Quote
  #7  
Old 13th October 2009, 08:59 AM
450SE's Avatar
450SE 450SE is offline
Aficionado
 
Join Date: Mar 2009
Location: Melbourne, Australia
Posts: 187
Default Re: Help required - engine cutting out

Thanks for all of your tips, gents.
My initial thought was fuel due to the surge / quick splutter while cruising or instant - but the rev counter shooting through the red line threw me a bit.
To be honest, I'm not sure when the fuel pump was last replaced but the previous owner is in the process of photocopying all of his old receipts for me.

At the moment I tend to be thinking along the lines of an earth near the battery, perhaps damaged when the battery was replaced.

The car was dropped off to the mechanic this morning. Of course, it didn't miss a beat on the way there or while I was driven back to my office. Typical gremlin...
__________________
Valium. Helping me get through the day since the 1980's.

Last edited by 450SE; 13th October 2009 at 11:35 AM.
Reply With Quote
  #8  
Old 13th October 2009, 09:40 AM
John S John S is offline
Connoisseur
 
Join Date: Feb 2008
Location: Sydney
Posts: 639
Default Re: Help required - engine cutting out

Driving up Kurrajong Heights My 450SEL cut out instantly and then started again almost in the same instant. I drove quietly home with no further trouble.

Put it in for a service and the mechanic (Frank Zimmer at the time) said the filter was so blocked he didnít know how the car managed to run.
Reply With Quote
  #9  
Old 13th October 2009, 10:07 AM
BAR
Guest
 
Posts: n/a
Default Re: Help required - engine cutting out

I had this some time ago, and incidentally it's how I met the godfather.

Initially I had an occasional miss, then it developed into something that I best describe as having a rev limiter attached... the motor just wouldn't go past 2,200 rpm.

In my case a replacement ignition control module (sourced from and quickly installed by the godfather 'Styria') cured my ills.

My considerations are all centred around electrical rather than fueling issues.

There is also the potential for an intermittent 'shorting' of the ignition leads, when under load, so cold and hot running under load (hillclimb or start off) would be the times when this may be noticed. Try opening the bonnet in your garage at night with the lights off and look for any signs of 'lightning'. Where the charge will short from the lead to engine metalwork.

Its amazing how much erformance can be bettered by fitment of new plug leads and coil leads. Better than a tune up in my case with the 450 and another older Ford.

A faulty spark plug can also cause similar symptoms.

Another possibility is the coil, but your seems to perform most times, so again I'd revert to other gremlins.
Reply With Quote
  #10  
Old 16th October 2009, 04:22 AM
Styria's Avatar
Styria Styria is offline
The Godfather
 
Join Date: Feb 2008
Location: Sydney
Posts: 8,577
Default Re: Help required - engine cutting out

Hi Tim, I've noticed that all seems to be well - obviously, with the threat of being confronted by the mechanic, the car probably decided to be on its best behaviour. Tell me, what did the mechanic do, and did he find anything at all out of order ?

Now, getting back to your first place query. I have noticed, in the past, that a battery that's down in charge will cause your rev-counter needle to jump up to about 4000rpm momentarily. That's one clue - perhaps your alternator is not charging properly.

Secondly, your green wire from distributor to ignition control module - make sure it is in good condition. If that's faulty, it can easily cause the sort of problem you have/had. Next would be to suspect the control unit itself. Just make sure you have a unit handy as a spare. I invariably include one as part of my tool kit when I take the car for a drive - out in the country.

Other than that, just make sure that your fuel filter is clean and free flowing, and then after that try and determine the condition of your fuel pump, or the relay for the pump as SEL69L has pointed out. Regards Styria
Reply With Quote
  #11  
Old 16th October 2009, 11:25 PM
WGB's Avatar
WGB WGB is offline
Aristocrat
 
Join Date: Feb 2008
Location: Perth Western Australia
Posts: 1,285
Default Re: Help required - engine cutting out

Just an idle thought.

Some years ago after doing some welding on my 450 I was driving along when the tacho started jumping all over the dial and the electric aerial started going up and down of it's own accord.

I drove some considerable distance with no driveability issues before I realised I had forgotton to plug the connector to the alternator back in - I had removed it before the welding to protect the electronics.

The flickering tacho needle is probably a low voltage in the system and was the first symptom in my 450.

I'd still look for a connection problem somewhere in the main feeds and earths.

Bill
Reply With Quote
  #12  
Old 19th October 2009, 05:20 AM
Styria's Avatar
Styria Styria is offline
The Godfather
 
Join Date: Feb 2008
Location: Sydney
Posts: 8,577
Default Re: Help required - engine cutting out

Hi Luke, After yesterday's conversation, I decided to look up the post we had been discussing and, of course, guess what ? Age (old) is starting to leave an imprint on the PC between my ears as I thought I was replying to Tim in WA. Anyway, now that I've got that off my chest, I'll just re-iterate the method of keeping the fuel pump operational at all times - if that's what might be your problem. As I said, just pull off the wiring loom that's connected to the switch near the fuel distributor.

Mind you, having said that, I still think that you have some sort of electrical problem. If you are able to, please keep us posted as to how you get on. Take a close look at that green wire from distributor to ignition module. BTW, hope you enjoyed the BBQ. Thanks to both of you for coming. Regards Styria
Reply With Quote
  #13  
Old 20th October 2009, 02:21 PM
450SE's Avatar
450SE 450SE is offline
Aficionado
 
Join Date: Mar 2009
Location: Melbourne, Australia
Posts: 187
Default Re: Help required - engine cutting out

The car is back in my garage again.
The mechanic had it for a week (which didn't bother me in the slightest) & found that the fuel pump was the most likely culprit for the spluttering, surging & stalling.
Originally, my suspicions were focusing on a possible damaged earth lead following a testy battery replacement, followed by a fuel line issue.

The fuel pump was buzzing quite loudly when I was called in last Wednesday afternoon - which I had never heard while sitting in the car, but was quite obvious once standing outside the vehicle.
The fuel filter which I had thought had been replaced in June was also choked full of gunk, which would have exacerbated the problem.

My mechanic drove the car home for a few nights and over the weekend, trying to cause the fault again, but couldn't fault the car.

While the car was in the shop, I also had him attend to a few other minor niggly issues:
* Patch up a minor hole in the exhaust near the rear muffler (1.5mm)
* Replace a faulty brake sensor
* Fit new horns. Hopefully the horse - I mean dog - that ran out in front of me a week or so ago will think twice. As will cab drivers.

He also:
* Refitted the battery properly (battery supplier was seemingly happy to just slam it in the hole & say "there ya go" )
* Adjusted all fluid levels / tyre pressures / light function & aim etc
* Did an overall condition report

Including $50 of fuel and 3.5 hours labour, the invoice came to just over $700.00, which to my way of thinking is money very well spent!
__________________
Valium. Helping me get through the day since the 1980's.
Reply With Quote
  #14  
Old 23rd November 2009, 10:37 AM
450SE's Avatar
450SE 450SE is offline
Aficionado
 
Join Date: Mar 2009
Location: Melbourne, Australia
Posts: 187
Default Re: Help required - engine cutting out

So back on October 20, I was claiming victory over my engine surge / spluttering / dying issue, citing a replacement fuel pump & fuel filter. Within days, the gremlin had reappeared.
My mechanic was unable to fit the car in for about a week, but wanted to have it for at least a week, possibly two, to properly diagnose the issue.
I got the car back last Friday afternoon.
After driving the car to & from his house for a number of days, the problem eventually reared its head. My mechanic believed it to be (I think he called it)the transistor module - the small metal box behind the front passenger side indicator light.
He sent it off to a specialist to diagnose & repair if required. The box returned a day or so later - unfaultable.
Refitted, the car faulted again that evening. The mechanic sent the box away again. When it returned a few days later, the specialist had diagnosed a fault & rebuilt the box. The car was driven for a few more nights my the mechanic.
When I collected the car, the mechanic told me that he didn't want to give it back to me yet. Asking if he thought the problem was still there, he responded 'No, it's such a lovely car to drive!'
__________________
Valium. Helping me get through the day since the 1980's.
Reply With Quote
  #15  
Old 23rd November 2009, 10:39 AM
SELfor50's Avatar
SELfor50 SELfor50 is offline
Aristocrat
 
Join Date: Feb 2008
Location: Capitown
Posts: 1,199
Default Re: Help required - engine cutting out

That's the control module or something??? Got a bunch of transistors in there?

What was the repair cost if you don't mind me asking??
__________________
If everybody is thinking alike, then somebody isn't thinking - General Patton

1978 W116 - 450 SEL - Finally locked
1979 W116 - 450 SE 6.9 - New Ticker
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Oil required for 6.9 suspension Michel MECHANICALS 88 22nd December 2012 07:05 PM
Tools required for basic 6.9 maintenance chrisp MECHANICALS 15 16th March 2009 06:57 PM
116 Leather Seats required John S MERCEDES W116 4 25th February 2009 08:16 PM
Caption Required Des TALKING TORQUE 11 5th October 2008 09:26 AM


All times are GMT +10. The time now is 03:33 PM.


Powered by vBulletin® Version 3.8.10
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Copyright Topklasse 2017