Plus2S130/4 K missfire

PostPost by: plus2OK » Sat Oct 22, 2011 10:22 am

Hi I have recently had a problem with starting my plus 2s130/4 K reg after virtually
Faultless performance for over two years. After using the car all day with no problems whatsoever I was on my way home doing 65 when it lost power and started to miss. I managed to pull into a pub car park where it died. After a rest it started on all cylinders ran at 3000 rpm for about 30 secs then started to miss again then died again temp was normal no black smoke no oil in radiator plenty of juice. I had run the tank dry 40 miles previous but refuelled with high octane and lead replacement additive. The RAC got me home
I have not gone into it really yet I thought I would get some ideas from you guys 1st
The car has electronic ignition ( I do not really know about these my last one just had points which I could cope with) And has Webber carbs, big valve engine
The chokes seem OK not stuck, there is fuel visible in the glass bowl of the mechanical pump . Perhaps it it fuel starvation either blocked in the gauze in the pump, or blocked jets. Then again could the coil be breaking down, when I had problems with the starter solenoid ( changed since no probs) I noticed the coil was getting very hot ( not the case now) how about the rotor arm in the dizzy I asume it still has one!) or distributor cap cracking?
Any suggestions would be gratefully accepted Cheers Paul
plus2OK
First Gear
First Gear
 
Posts: 48
Joined: 24 Jul 2009

PostPost by: RotoFlexible » Mon Oct 24, 2011 2:42 pm

I am going to guess fuel starvation resulting from crud stirred up from the bottom of the tank when you ran it dry. Is there a fuel filter between the tank and the pump, or just the gauze in the pump? (I just cured a fuel starvation problem by increasing the regulator setting - electric fuel pump - so I am predisposed to suspect fuel problems at the moment.)

Hope this helps, and good luck!
Andrew Bodge
'66 Elan S2 26/4869
I love the sound of a torque wrench in the morning. Sounds like... progress.
User avatar
RotoFlexible
Fourth Gear
Fourth Gear
 
Posts: 679
Joined: 01 Sep 2005

PostPost by: pauljones » Mon Oct 24, 2011 6:09 pm

Hi there,

Well your not really giving much info away here,so ill start with my ideas for what its worth.

First,start with the easy option,swap to points and try again.If it still fails high chance its the coil.But basicaly,sort out a good strong well timed spark.

second,if that doesnt get her going take off the fuel line from rear of pump and blow it backwards to the tank,that should clear the lines out.Then,while your there clean the filter gauze.Also and just for good measure,clean the carb filter gauzes.

Either way,start and work methodicaly and imsure she will be fine.

Paul.
Kick the tyres and light them fires...!!!!!!!
pauljones
Fourth Gear
Fourth Gear
 
Posts: 901
Joined: 09 Feb 2008

PostPost by: bob_rich » Mon Oct 24, 2011 6:31 pm

Hi Paul

I would think of fuel as a problem as other post suggests. For electrics with a distributor the voltage breaking down the rotor arm and shorting out and killing all sparks is common. Distributor caps tend to have voltage breakdown problems with not all cylinders playing up so engine may run but miss on one or two cylinders

If you have electronic ignition (that uses a standard and not a very low resistance coil) of whatever type If U can get a test meter set it on volts and connect from coil CB to ground with ignition on turn over engine slowly (spanner on crankshaft pulley bolt) test meter should read very low <2V a then read battery volts close to +12V when the spark should be produced. low reading all the time or +12V all the time means points or capacitor or electronic module faulty. Coil is best tested by substitution.

Hope this helps

best of luck

Bob
bob_rich
Fourth Gear
Fourth Gear
 
Posts: 564
Joined: 06 Aug 2009

PostPost by: Roy Gillett » Tue Oct 25, 2011 9:54 am

pauljones915 wrote:Hi there,

First,start with the easy option,swap to points and try again.If it still fails high chance its the coil.But basicaly,sort out a good strong well timed spark.

second,if that doesnt get her going take off the fuel line from rear of pump and blow it backwards to the tank,that should clear the lines out.Then,while your there clean the filter gauze.Also and just for good measure,clean the carb filter gauzes.

Paul.


First time I have heard of swapping to points or getting to the fuel pump as the "easy option" on a +2. I have the scars on the back of my hands from trying to get at both these compoments!

FWIW my guess would be fuel starvation because of crud in the filter. If you only have the filter in the pump it is tiny and easily blocked. My first move would be to take the fuel line off one of the carbs, pop it in a jam jar and turn the engine over . Almost no fuel and you know it is a fuel blockage. If you get a reasonable flow it still could be a blockage ; if it really spurts as the engine turns over, look elsewhere. By the way have the ignition turned off and use the under bonnet solenoid to turn the engine over (and it still might fire up while the button is pressed if the original ballast resistor wiring is still in place.)

Roy
User avatar
Roy Gillett
Second Gear
Second Gear
 
Posts: 188
Joined: 01 Oct 2003

PostPost by: Galwaylotus » Tue Oct 25, 2011 1:27 pm

Roy Gillett wrote:My first move would be to take the fuel line off one of the carbs, pop it in a jam jar and turn the engine over . Almost no fuel and you know it is a fuel blockage. If you get a reasonable flow it still could be a blockage ; if it really spurts as the engine turns over, look elsewhere.

It took me months to recognise a "reasonable" flow vs what it should be!! In the meantime I had replaced most of the ignition components and had the carbs off the vehicle. Eventually I found the filter the PO had installed just after the fuel tank in the boot. Replaced it, ran some flow tests, and that was the end of my engine dying problems!! :shock: :oops: :roll:
Mechanical Engineer, happily retired!

'67 S3 SE FHC

See Facebook page: W J Barry Photography

Put your money where your mouse is, click on "Support LotusElan.net" below.
User avatar
Galwaylotus
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1348
Joined: 01 May 2006

PostPost by: Sea Ranch » Thu Oct 27, 2011 3:54 am

Greetings.

Great responses you've received, Paul. I'll just add a personal experience . . . you can read about my adventure in this thread,
elan-f15/backfiring-t23637.html

You'll see many of the same symptoms and suggestions.

My first tip, and the way I more objectively and conclusively diagnosed one of my problems was simply to put a timing light/strobe on the spark plug wires and then the coil to cap wire. This way I was able to see instantly whether any of the cylinders was missing a spark (they all were, erratically) and whether the coil was delivering an unreliable/erratic spark (it was).

I was quite double-minded, alternating between fuel and ignition, but the timing light was a quick window into the ignition's condition (and you can see whether the ignition advance mechanism - weights or vacuum - is advancing the ignition timing while you're at it). Takes 2 minutes, no skinned knuckles and the information is easily worth the cost of the tool if you don't already have one.

My coil had a cracked top and was leaking, but hard to tell from it's installed position. Changed it and voila. But you can read all that in the thread above.

Best regards,

Randy
User avatar
Sea Ranch
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1141
Joined: 07 Mar 2011

PostPost by: plus2OK » Fri Oct 28, 2011 3:10 pm

Hi thanks for the suggestions.....has given me something to go on , I am tempted to go the fuel starvation route 1st as it all seems to point
to that, the fact that it runs OK'ish for 20-30 secs also to me suggests the ignition side is mostly OK. I will take a look after the weekend, and get back
with my findings. Thanks again for the help , I was beginning to think I had posted incorrectly no replies....then 6!! Cheers
plus2OK
First Gear
First Gear
 
Posts: 48
Joined: 24 Jul 2009

PostPost by: ardee_selby » Fri Oct 28, 2011 3:22 pm

plus2OK wrote: Thanks again for the help , I was beginning to think I had posted incorrectly no replies....then 6!! Cheers


Don't forget any "PMs" you may get.

Cheers - Richard
ardee_selby
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2197
Joined: 30 Sep 2003

PostPost by: plus2OK » Fri Oct 28, 2011 4:19 pm

Hey Richard/Randy thanks for your input.... I have just read your previous post Randy....all 5 pages of it!!!! Much of it is directly applicable to my current problem ( except my car does not have sufficient guts to actually move) If I can pick the bones from the advice you got hopefully I can soon cure the issue.
I am really busy this w/e but must find some time to chase up some of the ideas you had.... that dizzy cap picture!!! , and I have noticed before that my coil has run very hot ( almost too hot to touch) but left well alone as the car ran so well. I had run a check on previous posts, but must have put the wrong description in as your post did not come up. It makes you think how many problems can you have and still have a running vehicle ? Cheers again will get back
plus2OK
First Gear
First Gear
 
Posts: 48
Joined: 24 Jul 2009

PostPost by: plus2OK » Fri Oct 28, 2011 5:33 pm

Strike 1 I just had to try the dizzy cap after Randys experience.... all looked OK to me the contact was there the rotor arm did not look burnrd ( cleaned with fine emery ) the 4 pegs to the ignition leads were the aluminium type but looked OK . I managed t start the car but it ran very rough and not for long. Perhaps I should swap the coil next? I am concious that I dont want this to be a rerun of Randys post and bore you all to death! Cheers Paul
plus2OK
First Gear
First Gear
 
Posts: 48
Joined: 24 Jul 2009

PostPost by: Sea Ranch » Fri Oct 28, 2011 6:15 pm

You'll find it, Paul.

I only hope it's not your daily driver (as it is mine, at least for another week or so before wet/frost set in) :mrgreen:

If it's not, then you've got time and patience on your side.
User avatar
Sea Ranch
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1141
Joined: 07 Mar 2011

PostPost by: Galwaylotus » Fri Oct 28, 2011 6:55 pm

If the coil is running that hot it may well be breaking down. :roll:
Mechanical Engineer, happily retired!

'67 S3 SE FHC

See Facebook page: W J Barry Photography

Put your money where your mouse is, click on "Support LotusElan.net" below.
User avatar
Galwaylotus
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1348
Joined: 01 May 2006

PostPost by: ardee_selby » Fri Nov 04, 2011 1:02 am

plus2OK wrote:Strike 1 I just had to try the dizzy cap after Randys experience.... all looked OK to me the contact was there the rotor arm did not look burnrd ( cleaned with fine emery ) the 4 pegs to the ignition leads were the aluminium type but looked OK . I managed t start the car but it ran very rough and not for long. Perhaps I should swap the coil next? I am concious that I dont want this to be a rerun of Randys post and bore you all to death! Cheers Paul


Paul,

Don't worry about boring folks! So...any developments?

(I note you had a look-see inside the distributor cap, but did you remove the HT leads? The reason I ask is this post from Anna: post145091.html#p145091
"sometimes the small things..."

Cheers - Richard
ardee_selby
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2197
Joined: 30 Sep 2003

PostPost by: pauljones » Fri Nov 04, 2011 7:33 pm

Paul and Roy.

I really must agree with Roy,and clarify what I was meaning.As we all know it can be a bit of a pain.I was thinking the easy option was to swap to points then try runnning the engine again.If its ok,then fine.But basicaly swap over components until the problem goes away.This is the advice I was given in answer to an ignition fault and it solved the issue.in fact mine was down to a wire from the starter solonoid to the coil breaking up inside.As you have mentioned the hot coil,I, and many others would say changing it would be a good start.Try a lucas sports coil or a bosche blue.

I personally found getting to the points was fiddly to say the least.I ended up taking of the carbs for better access.This is why I said the easy option as everything is there.So to take off a fuel line and blow it through is no problem.

As it goes,I consider a fuel starvation problem to get worse over a period of time not come on straight away.however blowing it through is a preventitive measure in this instance.

I would still consider the ignition components to be the cause of this fault.

Keep hunting Paul, good luck.

Paul
Kick the tyres and light them fires...!!!!!!!
pauljones
Fourth Gear
Fourth Gear
 
Posts: 901
Joined: 09 Feb 2008
Next

Total Online:

Users browsing this forum: No registered users and 13 guests