Gradually Overheating?

[RevB]

If this is a full pressure Vanguard.....https://www.ebay.com/itm/255464747799
There are adapters and coolers but at this stage you're not anywhere near too hot for an air cooled. 250F is generally max for conventional oils and synthetics will take that up a bit more, but not much. Beyond 250.....

Don't go looking for problems that don't exist.

 

[Neo7]

I checked under the cowl but nothing but lite dust

 

[Skippydiesel]

In my very limited experience overheating is usually:

• Lack of cooling - As this is an aircooled engine, something restricting air flow.
• Running lean - carburettor not delivering the correct amount of fuel for the air : fuel ratio - something restricting fuel flow - "gunked" up jet or similar

 

[Neo7]

• Running lean - carburettor not delivering the correct amount of fuel for the air : fuel ratio - something restricting fuel flow - "gunked" up jet or similar

What about running rich? ... I fitted a new Air filter because the old one was quite dark with dust. ... I'll see how she goes on the next mow ;-)

 

[Skippydiesel]

No! A rich fuel air mixture will cool the engine. It will also carbon/soot up the plug(s).

One of the most common causes of a hot/cold engine indication, is a faulty thermocouple/sensor. As you have two (engine/transmission) is it possible to swap them around and see if they are consistent in their reading.

 

[Auto Doc's]

I have a Husky with a 24HP B&S. Some time back I fitted a dual temperature display to monitor the Transaxle temp (usually 65DegC) and the engine (oil filter) temp (usually 70DegC) and I have kept an eye on them both over the last few years. Tranny Temp is still the same but more recently I have noticed that when I finish mowing (the usual lawns) the engine temp is 99 to 105DegC.(221DegF).

Is that too hot? and any ideas what could be causing this heat creep?

Many thanks.
Neo

Remove the shrouds and clean the fins regularly. As I recall, B&S has a bulletin to do that for these engines. Aside from that, use the correct weight oil for the temperature conditions.

 

[Neo7]

I've already done that. I've been running the same grade of oil for ages. No recent changes there.