barrus Barrus Shire 45hp overheating

[Tracy D'arth]

11 minutes ago, alan_fincher said:

This boat wasn't built by Mike Heywood / Evans & Son, by any chance?

 

Curious, why do you ask?

[alan_fincher]

2 minutes ago, Tracy D'arth said:

Curious, why do you ask?

 

He regularly built boats with completely inappropriate skin tanks.  Our old 50 foot Evans & Son boat with a BMC 1.8, had a skin tank approximately 2 feet x 2 feet x 4 inches, and which when cut open was found to contain no baffles of any description.  How the previous owner had survived 10 years like that I have no idea!

We replaced by something like 9 feet x 2 feet x 1 inch, and proper baffles, and it transformed things.

 

I've looked at other Evans / Heywood boats of a similar age, and no two look the same in the skin tank department.  I think h made it up as he went along.

[Tony Brooks]

47 minutes ago, ronnietucker said:

Probably making myself look silly here, but I'm going to ask it out of ignorance and curiosity:

Saw someone on YouTube say that when they had an engine overheat someone told them it might be the blacking that's too many layers, or too thick, but others said it's a load of tosh. Plausible or tosh?

 

Curious as I've just done the blacking...

 

Not a load of tosh. I told you above that many narrow boats have undersized skin tanks for the engine. That means that if the old blacking is not removed in that area it can cause overheating. The thicker the blacking and the smaller the tank the more likely it is.

 

Note that the thinner the tank the better, thick tanks like Alan's 4" one, may be slower to heat up but then their cooling effect is worse than a thin one because coolant can flow through the tank while staying away from the cold surface.

 

PS it would not surprise me if Liverpool fitted undersized skin tanks.

Edited October 29, 2022 by Tony Brooks

[Tracy D'arth]

16 minutes ago, alan_fincher said:

 

He regularly built boats with completely inappropriate skin tanks.  Our old 50 foot Evans & Son boat with a BMC 1.8, had a skin tank approximately 2 feet x 2 feet x 4 inches, and which when cut open was found to contain no baffles of any description.  How the previous owner had survived 10 years like that I have no idea!

We replaced by something like 9 feet x 2 feet x 1 inch, and proper baffles, and it transformed things.

 

I've looked at other Evans / Heywood boats of a similar age, and no two look the same in the skin tank department.  I think h made it up as he went along.

I think it was often who welded up the tank. Mike had various folk working with him, some quite spuriously.  In the Evans days Mike was taking a back seat for much of the time, he was not a well man towards the end.

I fitted out a few Evans shells but never encountered a seriously under size tank. Many builders routinely undersized ( and still do ) I think.

[Tony Brooks]

I would add that on the present info air/gas in the top of the skin tank is the most likely cause but work through the list I posted hours ago.

[ronnietucker]

12 minutes ago, Tony Brooks said:

I would add that on the present info air/gas in the top of the skin tank is the most likely cause but work through the list I posted hours ago.

Yep. Will do that tomorrow.

Thanks for the advice!

What kinda temperature should the engine be running at? Roughly. I'm sure it'd depend upon where the engine is etc..

[Tony Brooks]

5 minutes ago, ronnietucker said:

Yep. Will do that tomorrow.

Thanks for the advice!

What kinda temperature should the engine be running at? Roughly. I'm sure it'd depend upon where the engine is etc..

 

That depends upon the thermostat. Unless it has been deliberately derated to provide slightly cooler water in the calorifier I would suggest a modern keel/tank cooled engine would run at around 85C. If derated take about 10C off that figure. If you have to take the thermostat out, as I explained, the opening value will be stamped on it so add a few degrees to that to allow for it restricting flow until it is fully open.

[Tony Brooks]

It would also be worth checking the rubber sealing washers on the coolant pressure cap. At canal speed damaged one should, in theory, make no difference, but at higher powers it could cause coolant loss.

[cheesegas]

1 hour ago, Tony Brooks said:

 

PS it would not surprise me if Liverpool fitted undersized skin tanks.

Early boats like mine seem to have oversized tanks - it’s the full height of the swim and pretty much the full length, stopping just short of the stern tube. Engine temperature barely changes when flat out. 
 

However, I’ve seen a couple of newer ones with bigger engines and smaller tanks…

 

[ronnietucker]

Just to update this: had someone out to have a look and it definitely seemed to be air in the cooling system. While the guy was working on it the temperature was going up. The guy had to put a lot more water in and there was a fair bit of air bubbling out while he was working on it.

 

Haven't taken it on a run yet, but once the air was out the engine was running for a solid half hour and the temperature sat in the mid-70's.

 

I think I'm good. Fingers crossed!

 

Thanks to everyone for the advice.