NL Timing Belt Replacement

[date]

OK - it is time to come clean! My NL has topped the 200000 km mark and I decided to replace the timing belt. Also the idler pulleys and the crankshaft oil seal whilst I was there. I replaced the belt at 100000 km but not the other items. I replaced the water pump about 105000km.

Lousy job, but eventually got it done. At 100000 km, I noticed a weeping around the crankshaft oil seal, so I ordered a new seal this time. This time, no oil leaks at all - celan as a whistle, but since I had the seal, better replace it. Getting the sprocket off was a bugger and I eventually got it off but bent the crankshaft angle sensor plate in the process. A bit of panelbeating and she'll be right. WRONG!!!!

Put the beast back together and it fired up first time. Took it for a run and hell, it really goes well. The old timing belt had a little slack - maybe I hadn't tightened it enough the first time round. This time it was fairly tight. Minor scraping noise which worried me, but after 5 km or so, it had gone. Maybe this scraping was the new belt and pulleys? WRONG! Took it for a few more runs - it really went well. For 50 km that is, then BANG! Massive backfire (running on gas). It blew the air cleaner apart. I recovered the bits of honeycomb and have panelbeaten them back into shape and reinstalled them. At this stage, all seems OK in that department.

It would crank over, trying to go but it seemed to be way too advanced, and eventually it would stall the starter motor - as if it was firing far too early. Popping like hell - on petrol or gas. Most of the time it would not fire at all.

High tension leads and spark plugs were OK - about 40000 km on them. I had a new set of plugs and leads, so I put them on as well. Still no go.

It isn't the HT leads - they are now well separated from each other, so I conclude that it must be the sensor which tells the spark when to fire. I cannot see any hope of getting cross firing through the leads now.

Strip down the whole thing again and pull off the crankshaft sprocket and I could see where it had been rubbing against the crank angle sensor on one of the tabs. Order a new crank angle sensor - I am still waiting for it to be delivered. I have straightened the sensor plate now and it runs true within 0.2 mm, so I am fiarly confident that it OK now. It was running out by about 1.5 mm or more.

Has anyone out there any ideas as to what else it could be. I am 99% certain that it is the crank angle sensor (because it had been rubbed and also the erratic timing of the engine spark). I have looked through other forums and can find very little reference to crank angle sensors, so I assume that they are reasonably reliable.

Any other suggestions before I reassemble it again?