Temp drop
- Thread starter Gregory S
- Start date
- Joined
- Jan 1, 2000
- RO Number
- 2006
- Messages
- 359
Here's my thoughts: If FWC with 180 degree thermostat and they were running at 190 or more then I would say yes the removal of the restrictions in the elbows allowed more raw water to flow through the heat exchangers to cool the anti-freeze. But if they were running at 180 or less and now they are even running cooler then I would suspect an additional issue with the thermostats.
If all you did was replace the elbows and temp dropped 10*, the conclusion seems pretty straightforward. [:-thumbu]
In light of your finding and result , you might consider a shorter replacement interval, say, each 3 or maybe 4 yrs. But as you know by now , checking often to see if you can still indefinitely keep your palm comfortably on the top of the elbow /risers at both warmed idle and cruise speeds provides the most basic clue to check/ fix RW flow.
Michael- I think the FWC XL engines had 160*F t-stats. And to my knowledge, the highest temp t-stats Crusader engines employ are 170* in the injected ones, at least on the MPI's.
In light of your finding and result , you might consider a shorter replacement interval, say, each 3 or maybe 4 yrs. But as you know by now , checking often to see if you can still indefinitely keep your palm comfortably on the top of the elbow /risers at both warmed idle and cruise speeds provides the most basic clue to check/ fix RW flow.
Michael- I think the FWC XL engines had 160*F t-stats. And to my knowledge, the highest temp t-stats Crusader engines employ are 170* in the injected ones, at least on the MPI's.
Sandy you're correct---160 degree stats. I agree, best to change earlier, but I was thinking that since I lay up for the winters, I could go 5 years. Also, the new Crusader elbows have a small brass plug on top that the old ones didn't have. Not sure what it's pulse is.
That brass plug can work as a vent. There's a small drain hole at the bottom of the elbows exhaust. At idle, it's possible for this drain hole to flow/drain water faster than the exiting raw water can keep the elbow filled with water. This can create an air pocket at the high point of the elbow and this air pocket can let the elbow get hot.
During testing of my prototype exhaust system, I found my drain hole was too big and was draining water too fast, even at mid range RPM(2500). I added a vent line from the top of the elbow and ran it to a point lower in the exhaust.
Even with clogged exhaust and elbows, adding a vent line where that brass plug is will allow water flow and keep the engine from overheating.
During testing of my prototype exhaust system, I found my drain hole was too big and was draining water too fast, even at mid range RPM(2500). I added a vent line from the top of the elbow and ran it to a point lower in the exhaust.
Even with clogged exhaust and elbows, adding a vent line where that brass plug is will allow water flow and keep the engine from overheating.
The brass plug on top of the elbow is for an exhaust overtemp alarm switch threaded hole. They had those holes for a few years then discontinued them, but may be including them again by popular request.
You can see the diagram item # 27/ Crusader Part # 020047 on pages 56 and 57 here:
http://www.crusaderengines.com/wp-content/uploads/2014/03/L510012.pdf
I don't recall what the switch's temp threshold rating is.
Seems like a great idea, but I never got around to wiring mine up to an alarm even with the switches in place , then the last (3 yr.)replacement elbows lacked the threaded hole.
I had a plan to run the alarm wiring through a 4 -LED light panel so I could tell at a glance the location of the alert source , but it was always "manana".
Such an alarm would alert to a potentially critical low-RW-flow situation much sooner than the intake manifold coolant temp alarm.
You can see the diagram item # 27/ Crusader Part # 020047 on pages 56 and 57 here:
http://www.crusaderengines.com/wp-content/uploads/2014/03/L510012.pdf
I don't recall what the switch's temp threshold rating is.
Seems like a great idea, but I never got around to wiring mine up to an alarm even with the switches in place , then the last (3 yr.)replacement elbows lacked the threaded hole.
I had a plan to run the alarm wiring through a 4 -LED light panel so I could tell at a glance the location of the alert source , but it was always "manana".
Such an alarm would alert to a potentially critical low-RW-flow situation much sooner than the intake manifold coolant temp alarm.