Help with 1974 jaguar e-type
 

I having been working on my 1974 s3 4 speed that has not
started in 20 plus years). Have cleaned out / replaced
most of the fuel system. There are 3 unknown hoses
exiting just above the gas tank on the right side of car.
Are these just venting hoses?

Also I have never worked with opus system before replaced
wires and plugs don't appear to have spark any
suggestions?
https://cimg4.ibsrv.net/gimg/www.jag...992e92950a.jpg


https://cimg5.ibsrv.net/gimg/www.jag...0de1ffaadb.jpg

Can't help with the Opus system, but have just replaced the gas tank in my 1973 S3 fhc. The three hoses - 2 short and one long should fix to small pipes in the top of the tank. (Don't see the pipes in your photos, but on my tank they're located in the top left in your photos). They go to an expansion tank that's located above and in front of the filler pipe.

SNG Barratt - The Ultimate Jaguar Parts Specialist


Expansion tank hoses, see link above ^

yes those are vent hoses..I did the same job on my 1974 xke which sat for twenty years. I too wrestled with the opus system. Take my advice bite the bullet and replace it with wither the SNG barret system or the pertronix. I did the SNG. No way around it. While you are at it you have to rebuld the carbs and replace the bypass vlaves. They are toast. You will not get it to idle properly without doing it. Now or later your choice it has to be done. PS make sure the PVC tubes are connected and cleaned. If you don't do this the oil will blow out your rear main seal like Niagra Falls. Call me if you want advice about the steering rack which will be leaking or replacing the brake hoses which can cause your brakes to seize.