Coolant system help

That is a catalyst warning light, either it is on fire (you'd notice) or not working (the car wouldn't know until the engine is running).

Probably it goes out when the engine starts.

No idea why it won't start though, check you didn't disturb any wires when you changed the hose.


Overheating could have warped the head, and lost compression, but I wouldn't expect the water to fill up if it were that bad.

Sounds promising.  Is there fuel and a spark?

Well I just pulled the plugs and all three came out with coolant on them. I'm hoping it's just an absolutely wrecked head gasket and I'm hoping the heads aren't warped. Either way I'm not set up to do the job myself. It will be in the shop on Friday but I may get a start on ordering parts because she's my daily driver. I'll be spending the day scouring the internet. 

Good diagnosis there.  There's a reasonable chance it will need a skim (and the block too) but that's best practice after any HGF.  It must have been driven miles without coolant.

I had been thinking about this before I saw the latest posts (they confirmed what I was thinking)

Either the hose was old and just let go or more likely the cylinder head gasket went,this would cause a loss of power, cause the engine to over heat and loss of coolant. It would also pressurise the coolant system and it was probably a combination of over heating and pressure in the coolant system that caused the top pipe to fail.

I haven’t had a head gasket go on a Jimny, but have on other engines and always had the head skimmed. If not when you put the new gasket in it might fail prematurely and you don’t really want to do the job twice. You can check a head with a piece of plate glass and feeler gauges, but it’s a bit time consuming and you need to know the tolerance. Expect to pay about £50 to £100 depending on how flat it is and how much needs to be removed and replaced.

If the head hasn’t been skimmed before, it’s usually a straight forward job for the right garage or motor engineering firm.

Thank you for the advice and the information. I appreciate you and everyone who took the time to help me. I'm in puerto rico so I'm hoping the shop I'm going to is capable of doing the job. If not I will likely have to send the head somewhere to be skimmed which means more money and more time. I absolutely agree that this I'd a job I would rather do once and do right. I've been told countless times that I have the only JDM jimny people have seen on the island so there's no way I'm letting this story end with a broken jimny. I'm just hoping now that I don't have to sell her once all is said and done to recoup my losses. I will send updates as I get them!