barrus Barrus Shire 45hp overheating

[ronnietucker]

Hi folks!

 

Looking for some troubleshooting advice on an overheating Barrus Shire 45hp engine on a 60ft narrowboat. This is the second time it's overheated. Never to the point of cutting out though.

 

After running for about 25-30mins the engine temp is way up at about 120'C with steam coming out of the engine bay and a bubbling noise (like a pot of boiling water).

 

What should I check first?

 

I checked the coolant level the first time it cut out and topped it up to the proper level. Checked it again after this second time and it had gone down a little bit, but not much. The oil seems to be within the min/max marks on the dip stick.

 

Any ideas??

Edited October 29, 2022 by ronnietucker
clarification of boat type

[StephenA]

I'd check the water pump

[matty40s]

Check the bleed screw on your skin tank, if there is a bubble in there, it doesnt matter how often or how much you top up your header tank, it will still over flow and overheat.

[ronnietucker]

2 minutes ago, matty40s said:

Check the bleed screw on your skin tank, if there is a bubble in there, it doesnt matter how often or how much you top up your header tank, it will still over flow and overheat.

I have to show my ignorance and ask what the 'skin tank' is. Is that the little white container for topping up the coolant?

[Tonka]

What about the thermostat

[Tony Brooks]

15 minutes ago, ronnietucker said:

I have to show my ignorance and ask what the 'skin tank' is. Is that the little white container for topping up the coolant?

 

If that image is of your boat then being GRP it won't have a skin tank. Please clarify the type of boat.

 

If it is GRP then it probably uses raw water for the cooling, probably via a heat exchanger. If so check the raw water inlet strainer, at this time of year you may have to do it several times a day.

[Alan de Enfield]

14 minutes ago, ronnietucker said:

I have to show my ignorance and ask what the 'skin tank' is. Is that the little white container for topping up the coolant?

 

From memory you don't have a steel NB but a GRP - is that correct ?

 

The skin tank is a tank formed by the steel hull, with a plate of metal welded onto the inside edge of the hull, but, leaving a 'few inches' gap between the two plates. This is full of water with hot water coming in from the engine, and whilst passing thru the 'tank' is cooled by the cold steel of the outer hull, then passes back into the engine.

 

In effect it the same as a car radiator.

 

 

[ronnietucker]

19 minutes ago, Alan de Enfield said:

From memory you don't have a steel NB but a GRP - is that correct ?

 

The skin tank is a tank formed by the steel hull, with a plate of metal welded onto the inside edge of the hull, but, leaving a 'few inches' gap between the two plates. This is full of water with hot water coming in from the engine, and whilst passing thru the 'tank' is cooled by the cold steel of the outer hull, then passes back into the engine.

 

In effect it the same as a car radiator.

Sorry, edited the original post to clarify that it is a steel narrowboat I'm talking about.

 

The bubbling I hear might be the water in that tank??? Just thinking aloud...

21 minutes ago, Tony Brooks said:

If that image is of your boat then being GRP it won't have a skin tank. Please clarify the type of boat.

 

If it is GRP then it probably uses raw water for the cooling, probably via a heat exchanger. If so check the raw water inlet strainer, at this time of year you may have to do it several times a day.

Edited post to say it's a narrowboat.

[Tony Brooks]

The bubbling you hear is probably just the coolant boiling. Remember NEVER put cold water into an engine that has just overheated. Doing so may distort the head or bock or even crack one of them.

 

1. Check the drive (fan) belt is in good condition and tight.

 

2. follow the large diameter pipe/hose running from the top of the engine, it should lead you to the skin tank., either on the swim side or possibly on the bottom of the boat. In the case of the latter it is likely to self bleed. The former, in the majority of cases will not so look along the top and along the top of the inside face of the tank to locate the bleed scare or plug. Loosen it or take it out while you watch it and top up the header tank. I expect that you will find a fair bit of air or gas comes out before the coolant. Refill the header tank and run the engine, manipulating the large hoses where they might trap air. I would do this with the filler cap off. When you see movement in the header tank stop the engine and vent the skin tank again. If that does not solve the problem follow below.

 

3. look down the front of the engine below the water pump pulley. If you see rusty or antifreeze coloured stains or signs of coolant drips the water pump is leaking, but this is far less common. With the fan belt slack try to lift the pulley up and down. You should have no movement so if you do the pump is worn so will soon leak.

 

4. When an engine overheats the modern waxstat type thermostats can vent wax so they open at a higher temperature so if there has been no problem found so far take the thermostat out and replace or test it with a thermometer in a pan of water on the gas. There is a temperature stamped on either the flange or the bottom of the wax capsule. That's the temperature at which it should START to open.

 

 

 

 

 

[ronnietucker]

36 minutes ago, Tony Brooks said:

2. follow the large diameter pipe/hose running from the top of the engine, it should lead you to the skin tank., either on the swim side or possibly on the bottom of the boat. In the case of the latter it is likely to self bleed. The former, in the majority of cases will not so look along the top and along the top of the inside face of the tank to locate the bleed scare or plug. Loosen it or take it out while you watch it and top up the header tank. I expect that you will find a fair bit of air or gas comes out before the coolant. Refill the header tank and run the engine, manipulating the large hoses where they might trap air. I would do this with the filler cap off. When you see movement in the header tank stop the engine and vent the skin tank again. If that does not solve the problem follow below.

 

Could air in the coolant line cause overheating?

[Tracy D'arth]

2 minutes ago, ronnietucker said:

 

Could air in the coolant line cause overheating?

Definitely.   Air does not conduct heat away, water does.

Air trapped expands greatly when heated, forcing water out until flow stops. Then it overheats rapidly.

[ronnietucker]

1 minute ago, Tracy D'arth said:

Definitely.   Air does not conduct heat away, water does.

Air trapped expands greatly when heated, forcing water out until flow stops. Then it overheats rapidly.

Gotcha.

But even when there seems to be plenty of coolant? The coolant is up to level (shown in the bottle where the coolant is put in). 

[Tracy D'arth]

9 minutes ago, ronnietucker said:

Gotcha.

But even when there seems to be plenty of coolant? The coolant is up to level (shown in the bottle where the coolant is put in). 

But are ALL the hoses and the skin tank FULL of water or are there air pockets? If not you will have no circulation. The water pump is an impeller circulator pump, it does not generate a positive pump head to any great extent, an air lock anywhere will stop circulation.

How did this overheating first occur? What was done before it started?

Edited October 29, 2022 by Tracy D'arth

[ronnietucker]

5 minutes ago, Tracy D'arth said:

But are ALL the hoses and the skin tank FULL of water or are there air pockets? If not you will have no circulation. The water pump is an impeller circulator pump, it does not generate a positive pump head to any great extent, an air lock anywhere will stop circulation.

How did this overheating first occur? What was done before it started?

I see. I'll need to find and check the skin tank first.

 

Nothing was done to the engine before that first overheat. I used the engine for a few hours no problem. Boat was out the water for blacking. Back in the water again and used for a few hours. No problems. Few weeks ago I went for 25-30mins down and back for a pump out and that was the first time it overheated. Topped up the coolant. Hoped that was it OK. Went for a pump-out again this morning and it overheated again on the way back. Coolant level was a teeny bit low, but not much.

[Tracy D'arth]

If its not loosing water from a leak, hose, pump spindle, tank corrosion, it could be a head gasket failed but get it tested before tearing it apart.

You can get it pressure tested with a tester used on car radiator caps if you have such a cap on the engine or you can get chemical testers that look for combustion products in the water.

[Tony Brooks]

1 hour ago, ronnietucker said:

 

Could air in the coolant line cause overheating?

 

Agree with Tracy but in addition the problem with air in the skin tank. You need roughly 1 sq ft of tank area per 4 hp so a 45hp engine needs over 10 sq ft, but less on canals where engines rarely develop maximum power. That has allowed numerous hull builders to fit undersized tanks. They work OK most of the time but now think about how a load of air trapped in the top of the tank prevents the water making contact with the whole outer surface. This in effect further reduces the effective area of the skin tank so it overheats more readily.

 

I wonder if you have fallen foul of leaves in the cut.  They tend to pack around the prop making the engine work harder and harder so if your skin tank area is a bit on the small side any attempt to maintain forward speed will cause the engine to develop more power and thus produce more heat. You will never see the leaves around the prop because as soon as you stop the prop they float away. When you get leaves around the prop the boat goes slower and slower. The answer is to pop it into astern for a moment or two. Trying to rev up to maintain speed can cause overheating and exhaust smoke.

[Bee]

Whenever I have had odd problems like this I find that undoing a jubilee clip at the end of as many hoses as I can reasonably get to and pulling the hose off (or at least until you can tell if there is water in it) is a good start. You need water filling every bit of the circuit. Also, if you have a jabsco or similar water pump with a rubber paddlewheel thingy in it then check that it has not shed all the little flaps, if it has then water will not circulate properly, if at all.  Both these are pretty non technical  jobs. Many pumps have a round brass plate over the end of the pump held on by a few brass screws, It is not full of springs and fiddly bits so nothing bad will happen if you take it off.

[Tony Brooks]

14 minutes ago, Bee said:

Whenever I have had odd problems like this I find that undoing a jubilee clip at the end of as many hoses as I can reasonably get to and pulling the hose off (or at least until you can tell if there is water in it) is a good start. You need water filling every bit of the circuit. Also, if you have a jabsco or similar water pump with a rubber paddlewheel thingy in it then check that it has not shed all the little flaps, if it has then water will not circulate properly, if at all.  Both these are pretty non technical  jobs. Many pumps have a round brass plate over the end of the pump held on by a few brass screws, It is not full of springs and fiddly bits so nothing bad will happen if you take it off.

 

If it is skin tank cooled then a Jabsco type pump is very unlikely, it will use an ordinary automotive water pump.

[ronnietucker]

54 minutes ago, Tony Brooks said:

 

Agree with Tracy but in addition the problem with air in the skin tank. You need roughly 1 sq ft of tank area per 4 hp so a 45hp engine needs over 10 sq ft, but less on canals where engines rarely develop maximum power. That has allowed numerous hull builders to fit undersized tanks. They work OK most of the time but now think about how a load of air trapped in the top of the tank prevents the water making contact with the whole outer surface. This in effect further reduces the effective area of the skin tank so it overheats more readily.

 

I wonder if you have fallen foul of leaves in the cut.  They tend to pack around the prop making the engine work harder and harder so if your skin tank area is a bit on the small side any attempt to maintain forward speed will cause the engine to develop more power and thus produce more heat. You will never see the leaves around the prop because as soon as you stop the prop they float away. When you get leaves around the prop the boat goes slower and slower. The answer is to pop it into astern for a moment or two. Trying to rev up to maintain speed can cause overheating and exhaust smoke.

 

I'll definitely try and find the skin tank.

 

I can't see it being the leaves as I did a fair bit of reverse. But now you mention the leave and prop... it did feel like the tiller movement was a bit more sluggish than normal? Not sure. Worth opening the weed hatch you think? Not something I've done before.

[Tony Brooks]

3 minutes ago, ronnietucker said:

I can't see it being the leaves as I did a fair bit of reverse. But now you mention the leave and prop... it did feel like the tiller movement was a bit more sluggish than normal? Not sure. Worth opening the weed hatch you think? Not something I've done before.

 

That is what the vast majority of new to canal boating says. The amount of reversing you do has absolutely no bearing on leaves around the prop.

 

The leaves pack around the prop when in ahead

The leaves float away a soon as the prop stops so you won't see them down the weed hatch.

When the boat gets a bit sluggish give it a quick burst of astern and look in the cur to see if a cloud of leaves float away.

 

Absolutely no point in looking down the weed hatch for packed leaves. They won't be there by the time you have the weed hatch open

[Tacet]

Check the drive belt to the water pump is present and reasonably tight.

The ignition (sic) warning light is not on too, by any chance?

[ronnietucker]

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...

[matty40s]

You are looking for something like this....

8 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...

Oy, Skin tank.....

[alan_fincher]

5 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...

I'd say theoretically possible, if it was on the margins beforehand, but only if blacking technique puts a lot more on than gets pressure washed off, as you prepare the hull.

What can certainly be an issue is over-plating.  If there isn't close contact between old steel and the over-plating much of the cooling ability will be lost.  I can remember a member on here with a boat that had ben over-plated over the area of the skin tank which had a major overheating problem.  He had the over-plate cut off in just that area, so it was back to "as built".  it cured the over-heating completely.

Of the suggestions made, I think the possibility of air trapped at the top of the skin tank is certainly one to look at.

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

 

[ronnietucker]

2 minutes ago, matty40s said:

You are looking for something like this....

Oy, Skin tank.....

 

Thanks. That's really helpful.  👍

1 minute ago, alan_fincher said:

I'd say theoretically possible, if it was on the margins beforehand, but only if blacking technique puts a lot more on than gets pressure washed off, as you prepare the hull.

What can certainly be an issue is over-plating.  If there isn't close contact between old steel and the over-plating much of the cooling ability will be lost.  I can remember a member on here with a boat that had ben over-plated over the area of the skin tank which had a major overheating problem.  He had the over-plate cut off in just that area, so it was back to "as built".  it cured the over-heating completely.

Of the suggestions made, I think the possibility of air trapped at the top of the skin tank is certainly one to look at.

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

 

 

Definitely finding and opening the skin tank is my task tomorrow.

 

I think this was made by Liverpool boats? Not 100% on that.