Warning.... Stupid Question!!

[paultallett]

This ones for the technical amongst you..... I know the heat can cause a dip in performance of an engine..... I remember a tread I commented on last year saying about it, but why does my engine always 'growl' more when it's very hot?? It's always been the same each year, weather gets very hot and she gets more vocal, especailly when getting on the plane.

Everythings normal t's & p's wise, just interested on what is the technical cause for said extra noise or is it because the engine has to work harder with the less dense (hotter) air it's breathing in??

See, I warned you it was a stupid question!!

Oh almost forgot, went to the Beaulieu river for the first time yesterday, anchored in the first reach and had a loverly swim in really clear water..... I've got a new favorite spot!! Don't tell anyone else about will you??


Regards Paul.

 

[colingr]

Sorry, don't know what causes it, but I noticed mine "growling" more at lot speed after the run across to the Island. Got me a bit concerned at first but same as you, all temps, pressures etc OK and performance seemed OK.

 

[mjf]

This ones for the technical amongst you..... I know the heat can cause a dip in performance of an engine..... I remember a tread I commented on last year saying about it, but why does my engine always 'growl' more when it's very hot?? It's always been the same each year, weather gets very hot and she gets more vocal, especailly when getting on the plane.

Everythings normal t's & p's wise, just interested on what is the technical cause for said extra noise or is it because the engine has to work harder with the less dense (hotter) air it's breathing in??

See, I warned you it was a stupid question!!

Oh almost forgot, went to the Beaulieu river for the first time yesterday, anchored in the first reach and had a loverly swim in really clear water..... I've got a new favorite spot!! Don't tell anyone else about will you??


Regards Paul.

anchored in the first reach

Was that before the turn by the yacht club place?

 

[paultallett]

anchored in the first reach

Was that before the turn by the yacht club place?

Thats the place..... I was clear of the no anchor zone!!!

 

[Firefly625]

This ones for the technical amongst you..... I know the heat can cause a dip in performance of an engine..... I remember a tread I commented on last year saying about it, but why does my engine always 'growl' more when it's very hot?? It's always been the same each year, weather gets very hot and she gets more vocal, especailly when getting on the plane.

Everythings normal t's & p's wise, just interested on what is the technical cause for said extra noise or is it because the engine has to work harder with the less dense (hotter) air it's breathing in??

See, I warned you it was a stupid question!!

Oh almost forgot, went to the Beaulieu river for the first time yesterday, anchored in the first reach and had a loverly swim in really clear water..... I've got a new favorite spot!! Don't tell anyone else about will you??


Regards Paul.

...ok, this might be the stupid answer .... but

Could it actually be that its a few months since your boat has had its bottom scrubbed and the fuzzy green growth is starting on the hull and the engine is just working that bit harder... so in other words its just a coincidence it warm, but that is what you would hope the weather is like mid way through the season!!

Got to say after putting 2 coats of International Inter-speed on my boat I noticed my trim tabs are looking very green & fuzzy! I can't believe the grow on them, I was putting it down to the sun...

.... but also owned a silly car once that had water injection in the air intake... as the colder the air getting to the engine, the more power.. so you could well be spot on with your original track!!

 

[CX54WEK]

Ours must be liking the heat. We got her maximum design speed (30 knots) out of her for the first time at the weekend!!!

 

[LittleShip]

This ones for the technical amongst you..... I know the heat can cause a dip in performance of an engine..... I remember a tread I commented on last year saying about it, but why does my engine always 'growl' more when it's very hot?? It's always been the same each year, weather gets very hot and she gets more vocal, especailly when getting on the plane.

Everythings normal t's & p's wise, just interested on what is the technical cause for said extra noise or is it because the engine has to work harder with the less dense (hotter) air it's breathing in??

Regards Paul.

Probably caused by the air being drier, cool air or air that contains more moisture will slightly increase the pressure in the cylinders (water cant be compressed) and therefore provide a little more power. Warm dry air may reduce that power and thin air at altitude will make an engine really struggle to perform. It's not unusual for performance engines to have a marked increase when in very wet conditions, problem is tyres dont perform better when it's wet!

Latestarter can probably explain this better if he picks up on the thread.

Tom

 

[paultallett]

Probably caused by the air being drier, cool air or air that contains more moisture will slightly increase the pressure in the cylinders (water cant be compressed) and therefore provide a little more power. Warm dry air may reduce that power and thin air at altitude will make an engine really struggle to perform. It's not unusual for performance engines to have a marked increase when in very wet conditions, problem is tyres dont perform better when it's wet!

Latestarter can probably explain this better if he picks up on the thread.

Tom

Wow, you learn something new everyday!! I never knew that about wet weather.... I'll try that one on SWMBO next time it's p1ssing it down she doesn't want to put to sea...... I can come in with the line 'But we'll get there quicker and use less fuel'...........Don't think it'll work on her though!!