Cold temperatures and bleeding the coolant on a Rover 200vi

[MGJohn]

This item refers to my son's 200vi but the techniques used can be applied to any car with similar problems.

Some of you may have seen the thread I started when my son swapped the engine on his 200vi ~ this is the one:~

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

We were relieved when the replacement engine fired up soon as the key was turned but, try as we might, we have not been able to bleed the cooling system so that the usually excellent heater warms up ... The engine appeared quite happy but, Ice Cold air only from the vents with the heater control switch fully clockwise ... on.

We had already booked the car in for an MoT on Wednesday ( tomorrow ) so needed to sort a few remaining jobs prior to the test. The screen jets were obviously frozen and so not working, that could be a failure. I tried an idea. I boiled up two full kettels of water and poured them into the screen wash bottle ~ located up front behind the bumper and exposed to the cold. I also poured a little hot water over both jet nozzles on the bonnet and tried the screen washers ~ they worked. The hot water had freed up the pipes and jets. I drained some of the water only and replaced it with screenwash designed to operate down to -10 C. Sorted.

I ran the engine for what must be best part of half an hour and it became quite hot, even at idle. With the bonnet closed I was hoping the trapped heat might free up the frozen heater pipes. It did not. Worse than that, the Radiator fan came on powerfully so I looked at the temperature gauge and the needle was climbing up close to the red. I switched off the engine.

As the Hot Kettle water did the trick with the frozen washer, I boiled up three full Kettles of water and carefull poured the hot water over the brass heater Matrix pipes and their hoses located behind the engine on the bulkhead. I started the engine again after a few minutes and still the heater blew icy cold... .

Couple more kettles of hot water over the hoses and matrix inlet and outlet pipes with engine still running and shortly after, the cooling system made an audible gurgling sound like a stiffled explosion and the gurging settled down after much squeezing of both top and bottom radiator hoses. I then looked at the Coolant Expansion bottle ~ Empty....

I moved to turn off the engine and as I opened the car door, HEAT.... Lots of it ..... Whoopee! Those sounds earlier was the Matrix being cleared and primed by hot coolant ~ hence the empty bottle ~ that coolant was now in the heater matrix. I topped up with fresh OAT coolant and the engine settled to a nice idle and that rad fan never came on again and the gauge needle steady just below half way...

I then realised I had double appointments tomorrow and so I either had to cancel the MoT or... I phone the test station and asked if I could drive the car there this afternoon and leave it for the test tomorrow. They helpfully agreed. I clocked 19 miles to the MoT station and the car ran beautifully ~ very pleasing... and the heat from that heater was superb ~ as was the Gloucestershire countryside under all the snow.

We now wonder what th tester will find tomorrow. Do not expect much but, you never know. The car has been stored off road on SORN for most of the year.

Obviously the coolant in the car's heater matrix was of poor quality or simply past it's best use date. Moral ~ ensure your coolant is always up to scratch and the washer bottle has good stuff in it to cope with these low temperatures.

Same old, same old ... a stitch in time here would have saved far more than the proverbial nine.

Meantime, I stopped and took a few pictures of the local area on the way :~





Nice, but, bluddy cold.... Roll on spring ...;)