Bear with me, but after reading the thread, my thoughts would be:

Several references to the valves both being closed and the dizzy pointing at no. One. This would suggest that the dizzy drive is installed correctly to the camshaft, but, is the piston actually near tdc?

I guess if the front pulley has the correct notch that's easy to see, but the flywheel isn't so easy. I like the suggestion of putting a compression tester on no 1 and hand turning the motor, or a screwdriver carefully in the plug hole.

It really sounds like the cam/crank timing is wrong and I'd want to prove that to save pulling the timing cover.

Just my thoughts,   Jon

Quote from: Eve on Mar 07, 2024, 01:32 PMHe's had a bang. It came out of the carb choke tube.
It has to be timing that is way out.

That's my thinking. I still think it's a possibility the ignition is 180 degrees out.
I think if the valve timing was wildly out there'd be contact between piston and valve.
I'm somewhat baffled without seeing it. Difficult to diagnose remotely.

I thought the 2.25 was a 'safe' engine? Valve > Piston contact not possible? Stand to be corrected.

Quote from: Gareth on Mar 07, 2024, 05:28 PMI thought the 2.25 was a 'safe' engine? Valve > Piston contact not possible? Stand to be corrected.

I had a look on line, not the most reliable source I know and the opinion is divided but more in favour of an interference engine. I must admit I only assumed it is.

Correct ... not possible in a Land Rover petrol, combustion chamber is machined into the head.



But in a diesel - yes. Don't ask how I know 

I'm always willing to admit wrong and learn something new.

Quote from: JonB on Mar 07, 2024, 01:54 PMBear with me, but after reading the thread, my thoughts would be:

Several references to the valves both being closed and the dizzy pointing at no. One. This would suggest that the dizzy drive is installed correctly to the camshaft, but, is the piston actually near tdc?

I guess if the front pulley has the correct notch that's easy to see, but the flywheel isn't so easy. I like the suggestion of putting a compression tester on no 1 and hand turning the motor, or a screwdriver carefully in the plug hole.

It really sounds like the cam/crank timing is wrong and I'd want to prove that to save pulling the timing cover.

Just my thoughts,   Jon

I've already yanked the timing cover off to triple check it looks correct, it's still off. Just waiting for some RTV to arrive as I ripped the oil sump gasket on the way off ... I can see piston through the spark plug hole so I assume it's at TDC, you can see the marks on the flywheel on the pics I uploaded on page 2 (I think). I'll check it's on compression with the finger trick. But I reasonably confident it is. I turned to whole dizzy 180 out and had flames come out the top of the carb. Perhaps it's correct, but i think it's going bang when inlet valve open. So we know it goes bang. It just doesn't go bang when I want it to go bang on compression. I get spark...

 I used an auto sparks plug light and I did notice there's a lot of small flashes followed by a big flash. Perhaps a condenser issue?

I've had the classic 180 out problem when I rebuild my s3 and was extra pre-cautious this time to make sure it was correct.   

Were both valves closed when you could see the piston? It could have been on the exhaust stroke.

Would it be worth just swapping the plug leads round to check if its 180 degrees out, it wont hurt

You mentioned the condenser , have you tried a different one ?

Make sure you get get recommended ignition parts like from the distributor doctor, I had problems with the car not starting years ago turned out the 2 spares condensers i had were both faulty wasted a ton of time, by chance I used an old condenser from a spare distributor which was the problem.
A lot of aftermarket stuff is very poor quality.

Hello all, good news!! I took it all apart again and put it together again exactly the same and it went!! Perhaps I missed something small. What it was will forever remain a mystery. Thanks for all your suggestions

Weird but well done. Something must have been corrected.

Quote from: Alan Drover on Mar 11, 2024, 04:33 PMWeird but well done. Something must have been corrected.

Must have been, timing chain off, double check valve timing, was correct... compression 110psi on all cylinders. All back together. Static timed at 6 degrees, off she went. Strange!!