8 replies to this topic

[Boatman]

Hello folks,
Ive searched the threads but cant see anything that could help, but apologies if Ive missed something.

The dizzy cap on the 998 was on the way out and on the way home she started misfiring. I fitted a new dizzy cap (Lucas) and she fired but was rough. Took plugs out and gave them a clean, after refitting she would not fire. Ive checked the firing sequence with No1 on tdc rotor arm is approx at 9 0clock (she seems to be 180 out from standard, this is how she was set up before when she was running well) and firing order 1342. Ive tried to check the plugs as best I can on my own with a jump lead on the block to plug and no spark.

Could the rough running / misfire kill the plugs? Ill get new plugs tomorrow anyway.

Any pointers or advice where to look next.

Cheers

[gazza82]

You did put the rotor arm back? I know it is stupid question but I remember a couple of mates doing that ... "I'll put this in my pocket to keep it safe!" ..

 

 

Also check the small carbon pickup in the middle of the dizzy cap is still there .. some "foreign" parts have known to drop these on installation.

 

 

Misfiring shouldn't damage the plugs .. you ought to get a spark from the lead though. If you aren't getting one from that, it isn't the plug. Check you haven't pulled another wire off .. or the coil lead hasn't been pulled out.

 

You need to go through it all systematically ..

[nicklouse]

if the rotor arm seems to 180 out are you sure it is not.

[Boatman]

Cheers.

No the rotor is in place, and yes it’s the sort of thing I’d do .... The cap is Lucas and the pickup seems to be in order. And I’ve checked the leads on the coil

[Boatman]

if the rotor arm seems to 180 out are you sure it is not.

I’ve checked No 1tdc rotor arm sitting at 9 O’CLock lead number 1to that position all others fitted accordingly from that point going anti clockwise...

[cal844]

Remove the spark plugs,
reconnect them to the leads,
Place the plugs on the head so you can see the gap in the electrode
Stand back a bit (so fuel cant get you)
Get an assistant to crank engine whilst you observe plugs....

[Cooperman]

If the position of the rotor arm is 180 degrees out, then the distributor shaft is that amount out. 

The best thing to do is to re-set the ignition and test it.

To do this, remove the distributor and then carefully remove the distributor shaft using a long 5/16" UNF bolt to withdraw it without it falling into the sump!

Re-fit it in the position shown in the workshop manual.

Then re-install the distributor setting it so that the points are opening at 6 degrees before top dead centre (TDC) when pistons 1 & 4 are approaching TDC. Look at the rocker shaft to see which cylinder is on the firing stroke. The valves on the firing cylinder will both have clearance whereas the other one at TDC will have no valve clearance. Re-connect the low tension and high tension leads to the distributor.

Fit the rotor arm and then fit the cap. The lead to whichever cylinder is firing will need to be on the cap in the position towards which the rotor arm is pointing.

Set the points gap to 0.015", clean the plugs and set the plug gaps to 0.025" and then check for a spark at both the points and the plugs. To check the plugs, make sure the leads are connected to the plugs and spin the engine with the body of each plug in turn against the block. It should have a healthy spark.

If after doing this correctly there is no spark then it will be either the coil or the condenser.

 

I think this is post number 20,000 from me. OMG!

[Boatman]

I think this is post number 20,000 from me. OMG![/quote]

Only 20,0000 Cooperman...

Seriously folks thanks for your input. Put new plugs in this afternoon and she fired right up. No 3 is not firing but i’ll Look into that tomorrow. I did the plug on the block test with the new plugs on each lead and I got a spark, the old plugs two were no spark one weak and one intermittent.

Most of my mechanical knowledge is on Diesel engines, any tips out with the service schedule for creeping the ignition system in good form?

[cal844]

[quote name="Boatman" post="3508024" timestamp="1511541609"]

I think this is post number 20,000 from me. OMG![/quote]

Only 20,0000 Cooperman...

Seriously folks thanks for your input. Put new plugs in this afternoon and she fired right up. No 3 is not firing but ill Look into that tomorrow. I did the plug on the block test with the new plugs on each lead and I got a spark, the old plugs two were no spark one weak and one intermittent.

Most of my mechanical knowledge is on Diesel engines, any tips out with the service schedule for creeping the ignition system in good form?[/quote]

Change the plugs, leads etc e 10,000 miles(change the engine oil and filter every 3000 miles at the most)...