8 replies to this topic

[Oskifisk]

Hey Theminiforum

 

My Mini 850 form 1977 is overheating after 2-3 min of idling, or the gauge says so. I have flushed radiator and changed the fluid, and both the hoses get hot after the thermostat opens. I took the cap off and started the engine, it was bubbling from the radiator, don't know if it is air in the system or fuel gasses coming from the head gasket? I opened the heater valve and turned on the heater, both the hoses also got hot. No hot air from the heater through (I think) The rocker cover and the top of the radiator is hot, but I can hold onto it with working gloves, also all the hoses. 

What might be the problem? can't figure it out.

 

Thanks in advance

 

 

 

[cal844]

Get an infra red temperature gun and measure the temperature at the sender and water pump. Then give the engine a compression test (dry, then add a small amount of oil to the cylinders and repeat.) Post your readings for both sets of tests here.

I had a guage that read just under the red hot, turns out there was no engine to body earth strap. Fitting this cured the issue

Hope this helps

[gazza82]

Could be several things including the thermostat is stuck, water pump worn or the system is furred up. Is the fan ok and the right way round?

 

Search on the forum and you'll find 101 things that can go wrong and you'll need to check!

[DeadSquare]

If it is overheating and there is lots of bubbling in the radiator it is a sure sign that the head gasket has blown, but that is no big deal and with a bit of help from here, if you have a spanner or two, you can probably fix it.

[Spider]

If it is overheating and there is lots of bubbling in the radiator it is a sure sign that the head gasket has blown, but that is no big deal and with a bit of help from here, if you have a spanner or two, you can probably fix it.

 

For it to be overheating so quickly, I'd say, this is it.

[MiniMadRacer]

As a quick cheap check, check that thermostat.(as the man above has said) ... it may not be fully opening...

[Oskifisk]

Turned out the gauge was placed too horizontal, so it showed 130 degrees after it passed half way point. Now i have fixed it and it shows a good temperatur of around 80 degrees, thanks for the comments!

Edited by Oskifisk, 20 November 2019 - 09:43 AM.

[DeadSquare]

That is splendid news.

 

Let us hope that any future problems are just as inexpensive to fix.

[Ethel]

3-3 minutes idling from a cold start?I'd be surprised if it got  that hot even from a blown gasket. A decent indicator if the bubbles are exhaust gases is if it'll pressurise without getting warm - put the cap on & squeeze the top hose after a cold start.

 

If there's heat in both heater pipes but no heat out of the heater it could be crud on the outside of the heater matrix.