Depends on the engine load and speed. Because the elbows are the last things to see the cooling water before it heads back to the briny, if the engine is being run hard, they can get very hot, well over 100 degrees. That doesn't mean the water inside is over 100 degrees, it's just that as the water coming in is already at around 70 degrees, it can't absorb much of the exhaust heat, which is over 400 degrees! without itself getting much much hotter.
The only time I put my mitts on the risers is after I recommission after winter layover, or after an impeller/outdrive install. At idle and at full operating temp if I can hold my hand on a riser, it's temp is OK. ...thinking my hand pull back is around 160 deg F.
Per Chris above (thinking he is speaking deg C), more speed & power = more exhaust heat. But it also = more raw/sea water flow through the manifolds/risers. So I go with the hand method at idle, and watch my temp gage when running.
Why wouldn't I be speaking Celsius? The USA has been officially a metric country for around 45 years now (Metric Conversion Act 1975). And metric has been officially accepted as valid units of measure for over 150 years! (Metric Act 1866).
Just saying... (About time you guys got with the program )
Get an IR temp gun it comes in handy for cooling system checks. I leave one in the boats tool kit. My OMC/Volvo exhaust elbows run at about 125 F* max after coming off plane.
thanks guys so I should be looking at 120- 180 max. if they get over 180 then its overheating id say, I just bought a laser thermometer to keep an eye on them .
Why wouldn't I be speaking Celsius? The USA has been officially a metric country for around 45 years now (Metric Conversion Act 1975). And metric has been officially accepted as valid units of measure for over 150 years! (Metric Act 1866).
