Another car running "poor and lumpy"

[ijonsson]

In another post I described how I thought that I had found the problem by finding a not sealing non return valve in the MU, still with steady pulse and spray on all cylinders, the problems continued with poor running / misfiring.

I changed HT leads, distributor cap, sparking plugs, rotor but not much better. Then, I thought " it can't be the Lumenition Optronic, can it"? I've only had it for some 7000 miles, less than 3 years old, but I put in points, condenser and the old 3 ohm coil, and now she runs as she should! The car is -71 PI so it hasn't any ballast wire to screw things up.

I'm starting to think one shouldn't use electronics in an old car, as I had another problem with the Kenlowe controller for the electric fan some time ago as well.

Anyone else out there who has had similar symptoms originating from a Luminition system? I thought that electronics were more "digital", either they work, or not at all.

 

EDIT: I just read the post regarding "ballast wire" and the funny thing is that I also put in a new high torque starter not long ago, coincidence that my electronic ignition as well got problems?

Edited June 11, 2014 by ijonsson

[John L]

What was the resistance of the coil you took off?

Did you have all the wires refitted when you put on the new starter motor?

 

John

[peejay4A]

I had lumenition on my 6 and it (the lumenition control box) repeatedly overheated and gave poor running. I changed it for an Aldon setup. On the 4A I stick with points.

Edited June 10, 2014 by peejay4A

[ijonsson]

What was the resistance of the coil you took off?

Did you have all the wires refitted when you put on the new starter motor?

 

John

The coil was 0,8 ohms, delivered together with Luminiton components, I also tried another 0,8 ohm coil (from MSD) without any success, as I suspected the coil might have burnt. All the wires? I only have one feed for the motor and one for the solenoid because I have a new alternator, and I've also replaced/disconnected the Ampmeter. The feed for Luminition was 12V from ignition switch.

[Peter Cobbold]

Dr Hugo Holden on p27 of his comprehensive analysis of coil versus CDI ignitions for TR4s mentions a points buffer amplifier:

www.worldphaco.net/uploads/CAPACITIVE_DISCHARGE_IGNITION_vs_MAGNETIC_DISCHARGE_IGNITION..pdf

""It should be noted that the spark energy is not significantly altered with a buffer amplifier. The gain is in longer lasting contacts in the contact breaker.""

They are a UK company, Boyer-Bransden:

http://www.boyerbransden.com/index.html

""All ignition units come with a 5 year warranty""

 

Peter

[JohnG]

Guys

I am trying to sort ouf the poor running on my TR

I have Luminition electronic ignition fitted, don,t know by whom or when.

 

Neil Ferguson is currenty rebuilding my metering unit, in an effort to cure the problem

Based on what I have read here, I will assuredly be targeting the ignition next, if the problem persists

I have a new Powerspark kit I can fit, but no 'points and condenser', so am comitted to electronic at the moment

 

John G

[ijonsson]

Guys

I am trying to sort ouf the poor running on my TR

I have Luminition electronic ignition fitted, don,t know by whom or when.

 

Neil Ferguson is currenty rebuilding my metering unit, in an effort to cure the problem

Based on what I have read here, I will assuredly be targeting the ignition next, if the problem persists

I have a new Powerspark kit I can fit, but no 'points and condenser', so am comitted to electronic at the moment

 

John G

Points and condenser are cheap, but I also did spend quite a lot on a rebuilt MU and injectors from Prestige Developments before discovering it was a faulty ignition system that was causing the problems. I've also heard since from others that it's not uncommon that the Luminition "black box" tend to overheat.

Edited June 13, 2014 by ijonsson

[flyer295]

Hello everyone,

 

I have a similar problem at the moment, having cured the drive train problem.

 

I have Luminition ignition which is new

The MU has just been rebuilt by Neil Ferguson

A Bosch pump has been fitted.

 

Symptoms :-

 

Firing on 4 or 5 cylinders but unable to determine which one.

Have removed leads one at a time whilst engine running. Removing cylinders 1 & 2 in turn produced little or no difference to the running

Changed plugs with No. 6 as distinct rev drop on this cylinder when lead removed. -- no difference !

Swapped 1 and 6 injectors -- no difference

I removed the air manifold assy and placed my hand over the air intake of each cylinder in turn. Cylinders 4 to 6 have good suction however, 1 and more so No. 2 has little suction -- This doesn't sound right, What would cause this, A leaking inlet manifold gasket?

 

Bob

[Peter Cobbold]

A broken inlet rocker on either 1 or 2 might explain the lack of suction.

But it would not explain why both 1 and 2 arent working judging by removing their leads: unlikely to be two rockers gone.

 

But 2 and 1 are at the same end of the MU:

1 5

3 6

2 4

What does removing 3 lead do?

Have you checked injector sprays?

 

Peter

Edited June 15, 2014 by Peter Cobbold

[John L]

Flyer, I think you need to do a compression test, could be the head gasket failed between 1 & 2 cylinders, had the same recently on, dare I say MGB.

John

[peejay4A]

Have you set up the throttle butterflies?

[jamesStag]

Bob.

I agree are the throttle butterflies setup and balanced? Try that first, then if OK, the other potential problems others have mentioned..

 

However I'd like to return to the original issue with Lumenition mentioned in the OP.

I have fitted lumenition to my TR6 18 months ago and it all went well I'm glad to day (The engine liked it, and idle is much smoother now)

I chose lumenition as we fitted it to our Stag around 20 years ago, and have never looked back since. all runs very well.

So my question is, have many people had issues with Lumenition systems, and If so what form did they take?

 

I mounted the black control box on the bulk head on the vertical part facing towards the side of the battery. It should be far away enough from the engine not to pick up heat, and get reasonable air circulation to cool. Doesn't seem to run very hot in normal operation.

Any comments appreciated...

 

thanks and regards,

J.

[flyer295]

Butterflies appear balanced.

 

Checked the compressions and No. 1 cylinder was 90 psi the others were 120 to 140 psi. Investigated the rockers and No 2 rocker had 0 clearance most of the others were too big, probably settling in after a little bit of running. Re adjusted the to .010" cold. Result's a little better. Still a bit lumpy on tick over but the higher revs seem to be a lot better. Further checks to be made but encouraging signs so far.I may expecting too much as I've only done a twin carb 6 cylinder before and that was smooooth on tick over. Are these throaty and lumpy normally on tick over?

 

Bob

[peejay4A]

How have you checked the butterflies? Idling is very sensitive to their balance.

 

Did you redo the compression test after correcting the valve clearances? Zero clearance is worrying, any clues as to how this might have happened?

[flyer295]

Checked them with a feeler gauge. They are all shut on tick over.

 

Re-checked No 1 compression. It's now up to 120 psi with the others. They were all set initially correct but bedding in is probably the reason behind them changing.

 

Still got a problem though. The misfire is throughout the revs. Getting to think it might be the injectors. I have checked them but they do vary a bit. To my mind there's not a lot left that hasn't been changed.

 

Bob

[peejay4A]

In my opinion they're best set using a flow meter off idle. But that's just my opinion.

 

The injectors should all produce the same cone shaped spray.

Edited June 16, 2014 by peejay4A

[flyer295]

Hi Pete,

 

As there is some doubt about them I've sent them off to be refurbished my Neil Ferguson.

 

Hopefully they'll be back at the end of the week.

 

Bob

[jamesStag]

Hi Bob,

good to see your update. for sure the tight valve clearance would make a significant difference.

 

In terms of a smooth idle, I believe that the PI's are tricky to set up to get a particularly smooooth idle (like a modern EFI). but with care you should get a fair steady one. (this is just from my father who had a 2500 PI saloon back in the 70's, TR6's I've come across and my own TR6).

I do agree that setting up the butterflies balance with a flow meter at idle particularly and also for an even pickup does make a significant difference.

 

Realise that the misfire is your main point of concern. Agree with getting the injectors checked out.

Is the misfire whilst driving on-load or just when rev'd as stationary? If it happens while on load too once your injectors are refitted then I'd suggest its more likely ignition related

Hope the injectors sort the issues for you.

 

cheers,

J.

[flyer295]

Hi J.

 

Heard back from Neil Ferguson about the injectors. 5 were ok but 1 wasn't. This sounds as if it's the problem. Anyway he's servicing them all and should arrive today/tomorrow.

 

I can't test the car under load. Well only the length of my drive. It's still strictly illegal. Not registered in this country, (import.)

 

Update when fitted.

 

Bob

[Peter Cobbold]

Hi J.

 

Heard back from Neil Ferguson about the injectors. 5 were ok but 1 wasn't. This sounds as if it's the problem. Anyway he's servicing them all and should arrive today/tomorrow.

 

I can't test the car under load. Well only the length of my drive. It's still strictly illegal. Not registered in this country, (import.)

 

Update when fitted.

 

Bob

You can get a bit of load by jacking up the rear wheels and using the brakes. They wont soak up many horsepower but enough to get you off tickover without the revs going high. And not for long.

[jamesStag]

Hi bob, ah ha Neil's feedback is encouraging. Reckon that'll sort it.

 

Remember that depending if the dodgy injector was partly or fully blocked, then due to the shuttle in the MU then the following inj is also affected. So problem is exascerbated. (Sorry if u already know this!)

 

Cheers,

J.

[flyer295]

The injectors arrived this afternoon, and I have fitted them.

 

It took a while to get it started,getting the air out but getting all 6 to pulse was something else, but by this time it was late in the day.

Eventually I managed it but it's still a bit lumpy.

 

Higher revs seemed smoother but opening the throttle quickly causes the engine to distinctly hesitate before it picks up.

Timing issue I think.

 

I have an old fashioned timing strobe. When connected No. 1 cylinder where should the timing mark appear? When I connected it

it showed as being considerably before TDC

 

Bob

[peejay4A]

11 degrees BTDC is a good start point.

[flyer295]

I've done as much as I can think of and it's still not right.

 

Syptoms :-

 

The engine is missing throughout the range.

From lumpy tickover the engine tries to stall prior to picking up revs when the accelerator is pressed.

 

All injectors are pulsing as if they're working properly

Changed the distributor cap and rotor arm

New plugs

New leads

Luminition is new.

Fuel pump new

Filter new

Metering unit is new

Injectors are new

One thing I have tried to get right and am not succeeding with is the timing

The metering unit has an almost complete hole showing on No6 outlet when on No 1 TDC. as it should

One thing is wrong and I'm not sure why is :- Timing the distributor

I have set the crank 11 deg BTD on No 1,

Adjusted the distributor so that the chopper blade on the Luminition is 2/3 rds across the eye ( checked with a meter showing 12 v or nothing between neg coil and earth)

At this point the heel of the rotor is by No 1 segment not the toe.

 

With this set up it will not start. To get it to start I have to alter the distributor considerably.

Then when it's running with a strobe fitted to No 1 lead then the timing light shows about 18 - 20 deg BTD instead of 4 deg ATDC

 

Could this be the drive from the cam shaft being wrongly positioned and if so can it be re positioned without stripping the engine?

 

Any thoughts anyone?

 

Bob

[peejay4A]

I think in your position I would reinstall a set of points and set the timing to 11 deg btdc at idle with a timing light (where did 4 deg ATDC come from-that's for US cars with vacuum retard). Then install the Lumenition and retime it using the timing light.