At first, it’s subtle.
The temperature gauge sits a little higher than normal.
Not overheating.
Not boiling.
Just… warmer.
You tell yourself maybe it’s the weather.
Maybe the load.
Maybe the hills.
But then the next day it does it again.
And the day after that.
That’s exactly what happened with this Kenworth.
The driver had noticed the temperature slowly creeping up over a few days. Nothing dramatic yet — but enough to know something wasn’t right.
Then another clue appeared.
Every morning there was a small puddle of coolant underneath the front of the truck.
Not a huge leak.
Not enough to leave it stranded.
But enough to tell a story.
So the truck came into the workshop before the problem became something much worse.
And honestly, that decision probably saved the engine.
Once we got it inside, we started checking the cooling system properly.
Bonnet up.
Torch out.
Straight away we spotted coolant weeping from the tell-tale hole underneath the water pump.
That little hole exists for a reason.
When the internal seal inside the pump starts failing, coolant escapes through that opening as an early warning sign.
It’s basically the water pump telling you:
“I’m on my way out.”
But that wasn’t the only problem.
Once we removed the fan belt and checked the pulley, there was noticeable movement in the bearing too.
The bearing had worn out, allowing the pulley to wobble.
That wobble had also been affecting the belt for quite some time.
The belt was glazed and worn from slipping — another sign the problem had been building slowly over time.
This is exactly why early symptoms matter.
A small coolant leak and slightly elevated temperatures don’t seem like a major issue at first.
But if that water pump had failed completely on the highway, the result could have been very different.
Loss of coolant.
Overheating.
Potential engine damage.
And that’s when a relatively straightforward repair turns into something major.
So we got to work.
New water pump fitted.
New belt installed.
Cooling system refilled and bled properly.
Then we ran the truck back up to temperature and checked everything thoroughly.
No leaks.
Stable temperatures.
Cooling system working exactly how it should.
By the end of the day, the truck was back on the road.
Problem sorted before it had the chance to become a much bigger one.
One of the biggest mistakes we see with cooling systems is waiting until the truck actually overheats badly before doing anything.
Most cooling system failures give warning signs first.
Slight temperature changes.
Small coolant leaks.
Noises.
Smells.
The trick is catching them early.
Because replacing a water pump is a lot cheaper than replacing an engine.
📍 Webbie’s Mechanical | Welshpool
📞 (08) 9353 1289
Same-day repairs. No drama. Just results.
