Engine block heater (41H)
Pretty Darn Active Enthusiast
Joined: Jun 2007
Posts: 311
From: Dry Heat, AZ
Re: Engine block heater (41H)
There is no way an engine block heater could possibly harm a catalytic converter. In fact, it is just the opposite. An EBH will reduce the time to go closed loop, which reduces the amount of CO and HC the cat sees from the rich mixture, extending the lifetime of the catalysts inside. In the Prius, they store hot coolant in a 'thermos' and pump it through the engine before a cold start. The only disadvangtage to an EBH is the electricity used and the possibilty of driving off while forgetting to unplug it. For fuel economy, emissions, vehicle longevity, etc. it is all good.
Ridiculously Active Enthusiast
Joined: Sep 2006
Posts: 1,678
From: Beautiful Pacific NW
Re: Engine block heater (41H)
There is no way an engine block heater could possibly harm a catalytic converter. In fact, it is just the opposite.
An EBH will reduce the time to go closed loop,
Exactly my point, the system may go to "closed loop" before the catalyst is "ready".
which reduces the amount of CO and HC the cat sees from the rich mixture, extending the lifetime of the catalysts inside. In the Prius, they store hot coolant in a 'thermos' and pump it through the engine before a cold start.
And since, for the Prius, that is an integral part of the factory design the catalyst warm-up period will allow, adjust, for it.
The only disadvangtage to an EBH is the electricity used and the possibilty of driving off while forgetting to unplug it. For fuel economy, emissions, vehicle longevity, etc. it is all good.
An EBH will reduce the time to go closed loop,
Exactly my point, the system may go to "closed loop" before the catalyst is "ready".
which reduces the amount of CO and HC the cat sees from the rich mixture, extending the lifetime of the catalysts inside. In the Prius, they store hot coolant in a 'thermos' and pump it through the engine before a cold start.
And since, for the Prius, that is an integral part of the factory design the catalyst warm-up period will allow, adjust, for it.
The only disadvangtage to an EBH is the electricity used and the possibilty of driving off while forgetting to unplug it. For fuel economy, emissions, vehicle longevity, etc. it is all good.
But no one will really know until enough EBH aftermarket equipped hybrids reach ~100,000 miles.
Hybrid and Ethanol Expert
Joined: Mar 2005
Posts: 3,616
From: All over the Central U.S.
Re: Engine block heater (41H)
Willard, that means you should never re-start your car after going to the store until it has had many hours of cold soak time, right????
Just think, all those dumb people out there starting a pre-warmed engine from driving their cars! Geeeezzzz...... Bet you've done this!
Just think, all those dumb people out there starting a pre-warmed engine from driving their cars! Geeeezzzz...... Bet you've done this!
Active Enthusiast
Joined: Jun 2008
Posts: 59
From: Milton Massachusetts
Re: Engine block heater (41H)
Carl, John & Billy. Thank you for the re-assurance. I hope to have the parts Fri or Sat so I can install this weekend. As always, I appreciate your wisdom and your willingness to share it!
Ridiculously Active Enthusiast
Joined: Sep 2006
Posts: 1,678
From: Beautiful Pacific NW
Re: Engine block heater (41H)
Willard, that means you should never re-start your car after going to the store until it has had many hours of cold soak time, right????
Just think, all those dumb people out there starting a pre-warmed engine from driving their cars! Geeeezzzz...... Bet you've done this!
Just think, all those dumb people out there starting a pre-warmed engine from driving their cars! Geeeezzzz...... Bet you've done this!
Enthusiast
Joined: Jan 2008
Posts: 40
From: Chicago
Re: Engine block heater (41H)
I think I will do the install since there is a difficulty level of 10, 
. Can anyone tell me if the hex key plug is on the radiator side or the firewall side? Also does anyone know how Ford runs the wires? I'd like for it to look factory.
. Can anyone tell me if the hex key plug is on the radiator side or the firewall side? Also does anyone know how Ford runs the wires? I'd like for it to look factory.
Hybrid and Ethanol Expert
Joined: Mar 2005
Posts: 3,616
From: All over the Central U.S.
Re: Engine block heater (41H)
I thought I had photos and directions somewhere, maybe even posted on this site... in a word or .pdf document... it was about 1 year ago I did mine. Do a search and I will too and let's see who finds it first!
Not my photos, but a good one to read:
https://www.greenhybrid.com/discuss/...ns-phev-15073/
Not my photos, but a good one to read:
https://www.greenhybrid.com/discuss/...ns-phev-15073/
Last edited by gpsman1; Nov 27, 2008 at 10:53 PM.
Active Enthusiast
Joined: Jun 2008
Posts: 183
From: Las Vegas, NV
Re: Engine block heater (41H)
Is this the only way (and best way) to get an engine block heater on the FEH? I have a 2008 and am looking to install one. I just don't know if it is worth it when morning temps in the winter months only get into the low 30s and high 20s.
