Not everything I do when working on cars is a success. Sometimes I completely cock things up, and since this website is more or less a candid view of me working on cars, I post everything, warts and all.
Since I did the injection system and thermostat on the SD1 I have had trouble bleeding the system and getting it to come up to temp correctly. It would very very slowly creep up the temp gauge, and just wouldn’t get to operating temp.
Initially I thought it was because the heater core is not working correctly, but I always had my suspicions about the thermostat itself. When I was fitting the housing with the new gasket, I had issues with the thermostat not staying in its little recess and slipping down.
The biggest give away I had done something wrong, was that there was fresh coolant under the thermostat housing after the engine cooled down. The gasket was leaking.
A combination of procrastinating, being away for the holidays, and not wanting to play 3 car musical cars AGAIN had really slowed down my efforts to fix the cooling issue, but tonight I decided to finally crack on with it.
After playing musical cars and getting the Rover in the garage, I took a good look at what I was working with. Sure enough, with a small mirror I could see coolant seeping through the gasket at the bottom of the housing.
I quickly drained the top hose, dumped a whole lot of coolant on the ground again, and removed the thermostat housing.
Sure enough, as soon as the thermostat was removed it was obvious I had stuffed it up.
The thermostat has slipped, and ended up compressing into the gasket. This left a rather sizable gap at the top of the thermostat, which was letting coolant through with the thermostat closed, clearly not helping my cooling issue.
Thankfully the thermostat itself looks OK, but the gasket is trash. I will have to get some gasket paper tomorrow and make my own.
I also decided whilst I was there, to remove and replace the old rusty and crusty looking hose clamp under the thermostat housing. I don’t want to do this job again, so this was a good opportunity to fix this before it became an issue. I need to reorient the new hose clamp though as it may interfere with the thermostat housing.
So I’ll grab some gasket paper tomorrow, make a new gasket, and do it right this time.