Motor Pinging 2.6L

[Ryan175]

Hi All,

On my way home from a trip on the weekend my 2.6L petrol motor started ticking/pinging and was struggling to get up past 80km/h.

Since I've been home I've checked the timing, which was at 6 degrees BTDC as per the manual. I played with the distributor a little to work out where it was happiest and it seems like all the way advanced is the only spot I can get the pinging to be least. Around 20 degrees BTDC. This has me confused because I thought advancing the timing causes pinging, but when I retard the timing the pinging gets way worse.

I've replaced the distributor cap and rotor, checked valve clearances and timing chain slack and tooth location. I've replaced all the vacuum lines and can't find any vacuum leaks around the carby or inlet manifold by spraying wd-40 and I dropped out all the old fuel and replaced with fresh stuff. It's been suggested it could be a clogged carby and running really lean (spark plugs came out white) and it has to be so far advanced to compensate?

I'm a bit stuck, I'd like to take it to the mechanic but they're booked out for the next couple of weeks so I'm not sure what to do.

Any advice is appreciated, thanks.

[Ratbago]

Check your fuel filter , its below the intake manifold close to the front frame leg , could also be your fuel pump shitting itself but i doubt it would run at all if that were the case . Id say its something to do with the carb , a carby rebuild kit is around 70 bucks. Or replace the factory carb with one off an XE-XF falcon .

[Ryan175]

Thanks Ratbago, the fuel filter is only a couple hundred kms old and was working fine and fuel flows through it easily, the fuel pump is also new, same deal a couple hundred kms old. I'm hoping not to have to rebuild the carby if I can help it but might have to, the car is at the mechanic at the minute getting diagnosed so I'll see what they say.

Thanks,
Ryan

[Ratbago]

Thanks Ratbago, the fuel filter is only a couple hundred kms old and was working fine and fuel flows through it easily, the fuel pump is also new, same deal a couple hundred kms old. I'm hoping not to have to rebuild the carby if I can help it but might have to, the car is at the mechanic at the minute getting diagnosed so I'll see what they say.

Thanks,
Ryan

Think of the benefits a carb rebuild could do though, improve fuel economy ( not that the astron is a very fuel efficient engine) and probably improve the drive ability . Hope you get it all fixed , we need more gen 1s on the road and tracks

[Ryan175]

Problems Found, the mechanic said the distributor plate was stuck advanced, probably due to age so they took it out and cleaned it up. The car now has an exhaust leak from the manifold gasket, as I was pulling that off I found the manifold had cracked through as well. I got a set of extractors but they didn't line up with the rest of the exhaust system and were interfering with the gearbox. So I've currently got the manifold getting welded and the extractors will have to wait till later to get put on.

I will rebuild the carby at some point, I'm sure it needs it, I'm just a bit busy at the minute and I'd like to do it when I have some time to sit down and do it properly so hopefully it can hang in there another couple of months.

Thanks,
Ryan