Club 80-90 Forums

Hi All,

This is me moving on from my previous post (https://club8090.co.uk/forum/viewtopic.php?f=2&t=57032" onclick="window.open(this.href);return false;) as I have ruled out a few things now.

(1980 Aircooled 2.0l Twin Carb)

So, since my van stopped working (turns over but wont start) all of a sudden I have replaced the following:

dizzy cap
rotor arm
ht leads
spark plugs
ignition coil

I don't get a spark from the coil lead whilst cracking engine (testing by removing the coil lead from the dizzy and holding closely to a metal part of the engine whilst cracking engine, is there another way?) so I am hoping someone (Mark - you have been helpful so far, any more tips?) would kindly point me in the right direction here on in.....

Now, Mark you mentioned I should check the Idle Stabilizing Unit, and to unplug the cables attached and join them together, however - as you see below I don't have a stabilizing unit! Is this common?



So I'm thinking perhaps I should change this >>



However when I broke down initially the RAC guy did have a spare so he swapped it over and there was no change, I have no idea on the condition of his unit however.

Is there any way to check that power is even getting to this part?? Sorry I cannot remember the name, are there any connections which may have come lose or corroded before this point? The Haynes manual hasn't been a great help, it doesn't seem to even tell you the correct way to put the HT eads on, actually - could some one please remind me please? Just in case the RAC fella mixed them up when I wasn't looking

Any help would be really appreciated as always

Dave

The Haynes has a procedure for checkin the hall sensor on the dizzy... you must follow it very carefully as its easily damaged by applying volts to it... you can "see" if its triggering the ignition module, with a volt meter though..
Check the coil has resistance somewhere near what the haynes says.. its also easier to leave the lead from the coil on and place it near some bare metal to see if there is a spark.. too big a gap and it wont jump it though.... you dont want to be holding it either...

Is there power to the coil when ignition on? (black wire IIRC) Green wire is the "trigger" from the ignition module.. any dodgy wiring or connection?

The ignition mudule is quite a common part if you can find one off a golf or audi from the 80's, there are 2 types supposedly fitted tot he T25, but they appear to be interchangable from what I have found...

However when I broke down initially the RAC guy did have a spare so he swapped it over and there was no change, I have no idea on the condition of his unit however.

Did he leave you with the original, its half as likely both will be duff?

If you follow Simon's guide, it might help to put a plug cap on the centre HT lead, and fit a plug... you want to make it as easy as possible to do a reliable test, 'cos you might be doing a lot! Look carefully at the plug, for the slightest sign of spark, however weak, when you do each test. And earth it well.

The Hall sender is often suspect, but as someone said, often cause problems before failing completely.

Wire on the spade connection on the distributor body?? or thereabouts.....
Is it connected ??
Knocked mine off when adjusting timing once, had me going for ages

Andy

Dave,

The Haynes manual hasn't been a great help, it doesn't seem to even tell you the correct way to put the HT eads on, actually - could some one please remind me please? Just in case the RAC fella mixed them up when I wasn't looking

Firing order is 1432, (more easily memorized 4321 perhaps)



Mike

My money's on the ignition module (black box with the heat sink on the back).

Ian.

on the air colds the earth wire for the ignition is a brown wire next to the dissy onto the engine block, check its connecting properly....

toomanytoys wrote:The Haynes has a procedure for checkin the hall sensor on the dizzy... you must follow it very carefully as its easily damaged by applying volts to it... you can "see" if its triggering the ignition module, with a volt meter though..
Check the coil has resistance somewhere near what the haynes says.. its also easier to leave the lead from the coil on and place it near some bare metal to see if there is a spark.. too big a gap and it wont jump it though.... you dont want to be holding it either...

Is there power to the coil when ignition on? (black wire IIRC) Green wire is the "trigger" from the ignition module.. any dodgy wiring or connection?

The ignition mudule is quite a common part if you can find one off a golf or audi from the 80's, there are 2 types supposedly fitted tot he T25, but they appear to be interchangable from what I have found...

Thanks for this - i will read up on the Hall Sensor. Will also get the amp meter onto those wires, see who is live etc....

I am picking up a replacment ignition module tomorrow from Volkspares so we never know, it could be that!

Thanks

HarryMann wrote:Did he leave you with the original, its half as likely both will be duff?

Hi there - yep I made sure he left the original Fairchild one in there - I am picking up a replacement tomorrow

Thanks!

toolsntat wrote:Wire on the spade connection on the distributor body?? or thereabouts.....
Is it connected ??
Knocked mine off when adjusting timing once, had me going for ages

Andy

Cheers Andy - pretty sure I checked all the spade connectors, that said it's always worth a second look

Ta!

Grun wrote:Dave,

The Haynes manual hasn't been a great help, it doesn't seem to even tell you the correct way to put the HT eads on, actually - could some one please remind me please? Just in case the RAC fella mixed them up when I wasn't looking

Firing order is 1432, (more easily memorized 4321 perhaps)

Mike

That's fantastic Mike - I will check that tonight! and will save your handy diagram

Many thanks.

Ian Hulley wrote:My money's on the ignition module (black box with the heat sink on the back).

Ian.

Seems to be a popular choice

I'll let you know how I get on.... Thanks.

Mocki wrote:on the air colds the earth wire for the ignition is a brown wire next to the dissy onto the engine block, check its connecting properly....

Cheers Steve - will definitely check that connection.

Ta

does the earth connect through a ring connector bolted via a 10mm bolt to the block/head? if so undo it , clean and tighten.

also make sure the plug on the dizzy/coil wire is nice clean and connected. some times the connections inside the plug can open up an not connect

does the solenoid on the carb click when the ignition is switched on and off?

billy739 wrote:does the earth connect through a ring connector bolted via a 10mm bolt to the block/head? if so undo it , clean and tighten.

also make sure the plug on the dizzy/coil wire is nice clean and connected. some times the connections inside the plug can open up an not connect

does the solenoid on the carb click when the ignition is switched on and off?

Hi BIlly,

thanks I will check those bits tomorrow, I can say that there is a definate click somewhere in the engine bay when the ignition is switched on but couldn't say where it comes from without a closer look

willgive feedback tomorrow
dave