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Electronic Ignition...or not?


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Having had my TR5 now for just over half a year, nearly all of which has been in the garage during the harsh Swedish winter, I am starting to notice some 'problems' (perhaps too strong a word) and turning to this forum where I get excellent responses/advice!!

My car starts and drives well, however when hot, the idling can sound and feel a little lumpy/ragged. The car is also slightly harder to start when hot and occasionally misses when accelerating. A friend of mine mentioned that electronic ignition may be my saviour but thought to turn to you all first. Would electronic ignition be a panacea for all things spark related? Perhaps I should start by simply replacing the coil? (Full tank of fresh 98 in the back)

If electronic ignition is the way to go, any recommendations (and is it a big job for a novice mechanic)?

Thanks as always!

/Andrew

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50 minutes ago, eandbee said:

Would electronic ignition be a panacea for all things spark related?

No. There is no real advantage over a properly adjusted points system for a road car, despite what the maker's publicity might say. The only thing is that you don't usually need to adjust it, as you occasionally must do with points .

Most electronic ignition systems replace the points either with a magnetic pickup or sometimes an optical one. The rest of the system remains standard so the spark energy is exactly the same. 

 

Edited by RobH
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I agree that points are fine for these; my Webered '250s both use them and apart from having to dodge poor quality condensers, rotors etc. are very reliable; the engines fire immediately and don't miss at all.

As for the TR5, isn't this typical? however when hot, the idling can sound and feel a little lumpy/ragged.  I have the P.I. cam in my driver and its idle is lumpy when hot too ( though there's no shake at all ).

 

Tom

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34 minutes ago, Tom Fremont said:

I agree that points are fine for these; my Webered '250s both use them and apart from having to dodge poor quality condensers, rotors etc. are very reliable; the engines fire immediately and don't miss at all.

As for the TR5, isn't this typical? however when hot, the idling can sound and feel a little lumpy/ragged.  I have the P.I. cam in my driver and its idle is lumpy when hot too ( though there's no shake at all ).

 

Tom

Thanks Tom. Sounds pretty much like mine actually although I get quite a bit of wobble - any ideas how to balance an engine?!? By the way, I LOVE your registration plate!!

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I have one of these fitted for some years now and no problems.  https://simonbbc.com/k1-powerspark-electronic-ignition-kit-for-lucas-22d6-25d6-distributor/  This fit and forget.

You can get the best ignition parts, some good points and condenser and rotor are from DD,  http://www.distributordoctor.com/  These may still some adjustment over time.

John

 

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Andrew

a true Tr5 can feel lumpy when hot and also when in town traffic !!especially those that did not have the Air bleed  conversion fitted to the inlet manifolds  , having the butterflies reset and properly adjusted helps greatly ,  and driving them hard  after town traffic  helps. as for electronic ignition a properly set up distributor with points rotor and condensor  from Martin the distributor doctor works great .

graham 

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I presume you have reset the points and swapped the condenser & coil? However sounds a bit more fuel related. Are you on fresh fuel or is it what's been in over the winter which may have gone stale with some of the more volatile ingredients evaporating over the winter.

These engines always sounds a little lumpy at idle - the key thing is it more lumpy than it used to be?

The injectors can get wedged with fragments of debris from the metering unit seals. They then either block or dribble which are more noticeable at low revs. Carefully pull the injectors out 1 by 1 whilst running and see if they are spraying properly.  Any that aren't disconnect and blow through with an airline (a foot pump will do with an airbed adaptor with the tip removed so it seals in the injector). If they rattle they will need a rebuild (or a new seal at the least). Reconnect and bleed.

If you have the kit measure the fuel pressure if it dips when you blip the throttle it may be the PRV might have stuck over the winter.

Whilst I am an advocate of electronic ignition I am unconvinced your problems are ignition related. However they are cheap so it won't cost a fortune to put it to the test via Ebay but I would look elsewhere.

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1 hour ago, Andy Moltu said:

I presume you have reset the points and swapped the condenser & coil? However sounds a bit more fuel related. Are you on fresh fuel or is it what's been in over the winter which may have gone stale with some of the more volatile ingredients evaporating over the winter.

These engines always sounds a little lumpy at idle - the key thing is it more lumpy than it used to be?

The injectors can get wedged with fragments of debris from the metering unit seals. They then either block or dribble which are more noticeable at low revs. Carefully pull the injectors out 1 by 1 whilst running and see if they are spraying properly.  Any that aren't disconnect and blow through with an airline (a foot pump will do with an airbed adaptor with the tip removed so it seals in the injector). If they rattle they will need a rebuild (or a new seal at the least). Reconnect and bleed.

If you have the kit measure the fuel pressure if it dips when you blip the throttle it may be the PRV might have stuck over the winter.

Whilst I am an advocate of electronic ignition I am unconvinced your problems are ignition related. However they are cheap so it won't cost a fortune to put it to the test via Ebay but I would look elsewhere.

Thanks for the advice. I will swap out the condenser and coil first - see if that helps. The fuel is fresh, have refilled several times since bringing the car out of the winter hibernation. I think someone told me it could be perhaps running on 5 cylinders..? Is there an easy way of checking this? Thought I would buy an IR thermometer over the weekend.

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Andrew

easy to check injectors are getting fuel if you lightly hold each pipe individually with the car running you will feel them pulsating , just like your own pulse in your wrist , a weak pulse or no pulse means no or reduced fuel pressure . 

graham

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I'm less convinced it is all that easy to be sure if an injector is opening properly just by the feel of the pipe. Will still pulse if there is a bit of crud holding the injector half open and squirting rather than spraying.

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Andrew I had similar issues as you last year, became the owner of the 5 back in August 2017. The car had been restored in 93 but had only done 6,000 or so miles since then.

I'm no expert but learning fast, that said I used to service my Triumph Herald back in the 70s and Fords after that, and that's about my limit. Since acquiring the 5 I have been enjoying 'one to one lessons' on solving problems with the 5 via a chap who did his apprenticeship with Triumph in the 60s - 70s, and this covered Lucas Fuel Injection.

First we changed the plugs, removed the black rota arm and replaced it with the red one (his recommendation) car has electronic election. Replaced the coil and after finding a leak replaced the fuel metering unit (FMU). Actually now have a second FMU as the new one before had the diaphragm break, not common he said.

Car still lumpy so we looked at the fuel injectors. He showed me a way on how to identify which injectors were problematic, we did this by feeling the level of pulses through the fuel lines to the injectors via the fuel metering unit, this became more evident when the engine was revved up. From here we identified two low pulse injectors.

We then took out each injector separately with the engine running and placed it into a large glass jar, some use cardboard box (have fire extinguisher to hand just in case) and noted the spray. When we came to the two problematic ones as identified by lack of the pulse, he was right, just a dribble. We couldn't improve them so I decided to have all six injectors refurbished.

Also had earth lead connection problems, reset the butterflies and can now say, hand on heart she runs beautifully.

Hope this helps.

Best wishes, Mike

Edited by MikeThomas
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