Merlo over heating

[YELROM]

Have a 14 reg Merlo 40.7 with a deutz engine, it started over heating when we had about finished buckraking so just went steady with the last few load to get finished
When we had finished we checked it round and the fan belt was a bit slack so tightened it and it runs about half way one the gauge as normal doing yard work
We are about ready to do second cut silage so went to a neighbours who was silaging the other day to try the Merlo and it started warming up to about 3/4 on the temperature gauge
The radiator has been blown out with a road compressor and the water looks normal in the expansion tank so is there anything else to check or will it be the head gasket

@Planttech think you reply to a lot of Merlo questions

 

[ACEngineering]

Have a 14 reg Merlo 40.7 with a deutz engine, it started over heating when we had about finished buckraking so just went steady with the last few load to get finished
When we had finished we checked it round and the fan belt was a bit slack so tightened it and it runs about half way one the gauge as normal doing yard work
We are about ready to do second cut silage so went to a neighbours who was silaging the other day to try the Merlo and it started warming up to about 3/4 on the temperature gauge
The radiator has been blown out with a road compressor and the water looks normal in the expansion tank so is there anything else to check or will it be the head gasket

@Planttech think you reply to a lot of Merlo questions

99% of overheating is always the rad. They take alot more effort to clean properly than people think!

 

[davidroberts30]

this^^

 

[Flat 10]

Sometimes air just won’t shift mess and a very careful pressure wash is what’s needed.....

 

[startinghandle]

A coating of dust on radiator core will act as insulation
Is fanblade clean?
Have you checked thermostat?
I remember some years ago the temp gauge needle went up in our Mazda
B2500 pickup so I turned heater on full and in a few seconds the needle dropped ...... new thermostat fixed problem

 

[daveydiesel1]

Id say ur rad is either blocked by dust or ir startin to block inside. The fact that shes ok when doin easy work shows that the rad is stil workin a bit but not fit to cope under full stress. I wouldnt be so fond of pressure washin it but have u got a parlour volume washer? Open it fully with revs on the engine

 

[ACEngineering]

Id say ur rad is either blocked by dust or ir startin to block inside. The fact that shes ok when doin easy work shows that the rad is stil workin a bit but not fit to cope under full stress. I wouldnt be so fond of pressure washin it but have u got a parlour volume washer? Open it fully with revs on the engine

might want new fan / idler bearings after that!

Pressure washer on low and direct in line with the core followed by air line, repeat till clean. if its a pig take it out of machine and do the same from both sides.

You cant beat alternating between air and water, its the only way to get them 100% clean.

Volume washer connected to the bottom outlet to back flush internals is great too. got a 2" hose here gravity fed from a massive water tank which i use for back flushing.

 

[HarryB97]

Are you running it in low gear or high?

 

[YELROM]

Are you running it in low gear or high?

Low gear when buckraking

 

[YELROM]

99% of overheating is always the rad. They take alot more effort to clean properly than people think!

The lad that drives it blew the rad out with the road compressor, i assumed it would be clean but
I will have a better look at rad and might take it out and give it a good clean as will not be able to get the pressure washer at it very well without bending the fins

 

[ACEngineering]

The lad that drives it blew the rad out with the road compressor, i assumed it would be clean but
I will have a better look at rad and might take it out and give it a good clean as will not be able to get the pressure washer at it very well without bending the fins

work a normal little blow gun over it at point blank range, you can hear the change in air noise when you hit a blocked fin.

 

[v8willy]

Ours overheating last week, new thermostat & waterpump sorted it, Perkins engine tho & wasn't that dear either.

 

[kill]

Lashings of pressure washer detergent and let it soak in really and then a good blast with the steam cleaner works wonders on rads

 

[sh40]

Could your thermostat be gammy and not opening fully? I know a lad that has a 2nd thermostat for buck raking. He has more holes drilled around the circumference to allow more water through. Runs cooler but puts back in normal thermostat for winter.

 

[Planttech]

Have a 14 reg Merlo 40.7 with a deutz engine, it started over heating when we had about finished buckraking so just went steady with the last few load to get finished
When we had finished we checked it round and the fan belt was a bit slack so tightened it and it runs about half way one the gauge as normal doing yard work
We are about ready to do second cut silage so went to a neighbours who was silaging the other day to try the Merlo and it started warming up to about 3/4 on the temperature gauge
The radiator has been blown out with a road compressor and the water looks normal in the expansion tank so is there anything else to check or will it be the head gasket

@Planttech think you reply to a lot of Merlo questions

Hi I would advise removing the rad as @ACEngineering has said. Deutz engines on the whole are pretty good so that would be my first port of call. Certainly the cheapest place to start