33 replies to this topic

[Captain Mainwaring]

This topic has become very silly.

If owners want to run their engines with no coolant for minutes on end, and others are advising that it is OK to do so, then it's their choice to take their advice from whichever source they like.

 

 

It's not silly at all really. There is some engineering and maths that can be done to give you an idea of how much the major components will get hot during a 1 minute run, trouble is many people rely on old wives tales and hearsay rather than backing up claims with a few pencil and fag packet calculations.

 

The guy needs to run for seconds rather than minutes, at idle, with the correct amount of oil in it, he'll be just fine, though he may want to pop off the fanbelt to avoid running the waterpump dry. At idle he's not going to cook anything up for 60 seconds of running from cold.

 

There's too much reliance on a book by someone and a book by someone else rather than thinking things out for oneself.

[adam_93rio]

I've ran an untested a series with no coolant system plumbed in for a minute or so to check that it started and ran, I've done this plenty of times and never had any problems or caused damage.
A dry start shouldn't damage it if ran for a little while at idle, although I agree with what people are suggesting that anything more or putting the engine under load no doubt would cause damage

If you're scared it will cause damage then plumb the radiator in, but it's a lot of messing about for a 30 second job just to take it all apart again...then re fit it all again

[Tamworthbay]

My 3 miles in the Spitfire included starting it, driving away, melting all the ice in the block, pumping out the coolant and then it seizing. I reckon I drove it for 5 minutes before it seized - and, boy oh boy, did it seize. It was totally without coolant for, I guess, about 1 minute. Engine was badly damaged and needed a replacement.
 
However, if anyone wants to take the risk, then it's up to them. Water cooled engines are meant to be, well, water cooled.
 
I ran a Land-Rover Discovery for 10 seconds yesterday to check the cam belt change before re-fitting the rad and filling with coolant. For me that is quite enough.

 
I'm surprised that as a very competent engineer that you just follow the thinking of others without doing the maths for yourself.
 
My CBX (1050cc 6 cylinder - 130HP air cooled runs oil temps of 130C,) doesn't seize up at idle with no airflow.
 
My wife kindly ran my 3.2 litre diesel pajero without water until it stopped because the injector pump got so hot that it thought it was a washing machine - It cooled down just fine and suffered no damage (don't try it at home)
 
No, I wouldn't take the mick, and no I wouldn't gun the engine - but I would be happy to run a cold engine up to idle for a minute or two without any concern.

would that be the CBX with the MASSIVE surface area due to EXTENSIVE finning as with any air cooled engine that would create a convection current even at stand still and therefore not need active airflow? (Nice bikes them)

[Captain Mainwaring]

 

 

My 3 miles in the Spitfire included starting it, driving away, melting all the ice in the block, pumping out the coolant and then it seizing. I reckon I drove it for 5 minutes before it seized - and, boy oh boy, did it seize. It was totally without coolant for, I guess, about 1 minute. Engine was badly damaged and needed a replacement.
 
However, if anyone wants to take the risk, then it's up to them. Water cooled engines are meant to be, well, water cooled.
 
I ran a Land-Rover Discovery for 10 seconds yesterday to check the cam belt change before re-fitting the rad and filling with coolant. For me that is quite enough.

 
I'm surprised that as a very competent engineer that you just follow the thinking of others without doing the maths for yourself.
 
My CBX (1050cc 6 cylinder - 130HP air cooled runs oil temps of 130C,) doesn't seize up at idle with no airflow.
 
My wife kindly ran my 3.2 litre diesel pajero without water until it stopped because the injector pump got so hot that it thought it was a washing machine - It cooled down just fine and suffered no damage (don't try it at home)
 
No, I wouldn't take the mick, and no I wouldn't gun the engine - but I would be happy to run a cold engine up to idle for a minute or two without any concern.

would that be the CBX with the MASSIVE surface area due to EXTENSIVE finning as with any air cooled engine that would create a convection current even at stand still and therefore not need active airflow? (Nice bikes them)

 

 

Nowhere near as much as you think and very ineffective at standstill - the point being that it won't seize up when idled from cold. Neither will the Mini

And thanks, yes it is a nice bike - this one is good for about 125hp now and will spin it's back wheel on a dry road in 3rd without lifting the front end up