Jimny giving me a few headaches...help please!

[Shorn]

Hello all,

Ive been looking for somewhere to ask questions on Jimnys for quite a while so hopefully this is the place!

I have a 2001 1.3 Jimny Soft top, which in January needed the engine replacing. A friend assisted in the engine swap and we successfully (or he mainly did) swapped the engine for a 1.3 from a 2002. (Basically exactly the same)

The car has been running fine, up until recently. The other day after driving for around 30 mins I parked up and noticed water spilling out from under the bonnet and noticed steam aswell. I popped the bonnet and the reserve tank was bubbling up (basically boiling)

Now this has been happening off and on for the past few weeks and some times the reserve tank will be completely empty after driving for a while.

The temp gauge in the car is reading normal and it has not actually overheated at all stopping the car from functioning.

I was hoping that someone might be able to offer any assitance with this, ideas or anything.

The little Jimny has cost a bomb in repairs so far so I want to make sure ive done all I can before handing ot to the garage!!

Thanks in advance!