Do high revs shorten engine life?

[Puggy]

This is a very interesting topic with some good replies..

So, I have a Ford 2702E 4.5 litre normally aspirated diesel (c 1985 vintage) with approx 2500 hours on it. Starts and runs a treat. I get approx 6.5 knots at 1500 rpm and 7.3 at 1650 rpm and I almost never exceed this. The manual says that max continuous is 2500 rpm and do not exceed is 2700 rpm. So is it bad to run it at gentler RPM? It is a nice speed, the engine is quiet, little vibration, makes nice progress etc. No turbo to clog up, engine reaches a nice temperature. Many gennies run at 1500 rpm all day and all night. Any thoughts? I have a feathering MaxProp and so it would be easy to alter the ratio but I like it how it is...

 

[Fire99]

This is a very interesting topic with some good replies..

So, I have a Ford 2702E 4.5 litre normally aspirated diesel (c 1985 vintage) with approx 2500 hours on it. Starts and runs a treat. I get approx 6.5 knots at 1500 rpm and 7.3 at 1650 rpm and I almost never exceed this. The manual says that max continuous is 2500 rpm and do not exceed is 2700 rpm. So is it bad to run it at gentler RPM? It is a nice speed, the engine is quiet, little vibration, makes nice progress etc. No turbo to clog up, engine reaches a nice temperature. Many gennies run at 1500 rpm all day and all night. Any thoughts? I have a feathering MaxProp and so it would be easy to alter the ratio but I like it how it is...

I'd say 1500-1700 RPM that 'redline's' at 2500 is perfectly fine.. I know diesel engines like to be worked and need to be under load regularly to keep them in fine fettle. I wouldn't be concerned at the rpm you're running at.

 

[ianj99]

This is a very interesting topic with some good replies..

So, I have a Ford 2702E 4.5 litre normally aspirated diesel (c 1985 vintage) with approx 2500 hours on it. Starts and runs a treat. I get approx 6.5 knots at 1500 rpm and 7.3 at 1650 rpm and I almost never exceed this. The manual says that max continuous is 2500 rpm and do not exceed is 2700 rpm. So is it bad to run it at gentler RPM? It is a nice speed, the engine is quiet, little vibration, makes nice progress etc. No turbo to clog up, engine reaches a nice temperature. Many gennies run at 1500 rpm all day and all night. Any thoughts? I have a feathering MaxProp and so it would be easy to alter the ratio but I like it how it is...

Leave it alone - its just fine as it is.
Modest rpm and load means your engine should last another 30years if you continue to be diligent with the servicing.
Ian

 

[Lakesailor]

This is a very interesting topic with some good replies..

So, I have a Ford 2702E 4.5 litre normally aspirated diesel (c 1985 vintage) with approx 2500 hours on it. Starts and runs a treat. I get approx 6.5 knots at 1500 rpm and 7.3 at 1650 rpm and I almost never exceed this. The manual says that max continuous is 2500 rpm and do not exceed is 2700 rpm. So is it bad to run it at gentler RPM? It is a nice speed, the engine is quiet, little vibration, makes nice progress etc. No turbo to clog up, engine reaches a nice temperature. Many gennies run at 1500 rpm all day and all night. Any thoughts? I have a feathering MaxProp and so it would be easy to alter the ratio but I like it how it is...

If you read my earlier post you'll see that engines each have their own sweet spot. It's that speed when the out-of-balance forces are least noticeable,when the harmonics have blended together and nothing is thrashing or clattering.
In petrol engines the sweet spot is often a lot lower than maximum revs. For instance the big end has lateral movement on the crank journal (longitudinal really) and usually at 4000 rpm and above it starts floating back and forth. Some engines can get very thrashy when extended, others smooth out. You really need to find out how your own runs best.
You seem to have found the one for yours.