Block Heaters

[MetroMPG]

Installation difficulty is very different depending on car & heater style.

The location of my OEM heater was the rear of the block underneath the intake manifold. It was a ***** to install - several hours. YMMV.

[diamondlarry]

I have a question about the lower radiator hose heaters. The instructions say to mount it into the lower hose with the element facing toward the block. In my car, the thermostat is in the lower hose. My question is this: will the block heater work in the lower hose, or should I install it in the upper hose since it will have a direct link to the cylinder head? Thanks.

[MetroMPG]

The hose heaters are supposed to work by convection, so you won't heat the engine if it's in the upper hose (hot coolant rises).

I'm surprised the OEM heater (you did say you ordered it, didn't you?) is an in-line hose style. I've read they're not as effective as the frost plug type.

Do you know its watts rating?

[diamondlarry]

Originally Posted by MetroMPG

The hose heaters are supposed to work by convection, so you won't heat the engine if it's in the upper hose (hot coolant rises).

I'm surprised the OEM heater (you did say you ordered it, didn't you?) is an in-line hose style. I've read they're not as effective as the frost plug type.

Do you know its watts rating?

It is a 600W heater. I know the hose type heaters aren't the best but, my skills(or lack thereof ) were not up to doing the frost plug and since money is tight I probably couldn't afford to have it done.
PS: I was hoping you were on today Metro.

[MetroMPG]

600W is pretty serious. Maybe it'll be OK. Though you'll want to monitor it: one guy wrote that his inline hose heater would boil the coolant at the heater, but not get the engine very warm.

I'm using an external bolt-on 300W block heater (shaped element). It's on the very top of the back of the block, under the intake manifold and straddles a steel coolant line. Seems to work OK, but a lot of heat is wasted to the air.

But if I knew then what I know now, I would have installed the frost plug style.

You might also consider insulating the coolant hose between the heater and the block.

[diamondlarry]

I just checked awhile ago and I thought I could feel boiling on the hose on the element side of the heater. I seem to only have about 4-6" of hose between the heater and where it hooks onto my thermostat housing.

[GasSavers_Brock]

I shouldn't tell you I have a 1000w zerostart unit, although it has a thermal limit of 200F and also a secondary over temp shutoff. It takes about 90 minutes at 32F to get to the point where it starts to cycle and about 120 minutes at 0F. My unit is on the lower side of the radiator and uses natural convection. If you set the cabin heater controls to defrost you get some convection in to the cabin area and if I plug in outside it will melt snow and ice off the windshield

[MetroMPG]

I also use a compact 1000 watt ceramic heater inside the car. It gets plugged in with the block heater, about 45 minutes before I need to leave (give or take, depending on ambient). So both the interior and block are toasty.

[MetroMPG]

So, Larry - I know you played with it today. Let's have some numbers!

EG - 1 hour EBH = how much above ambient? etc..

[diamondlarry]

Originally Posted by MetroMPG

So, Larry - I know you played with it today. Let's have some numbers!

EG - 1 hour EBH = how much above ambient? etc..

I haven't actually let it cool down completely yet since the install. Soon after I got it installed, we went to my sister-in-law's for 3-4 hours. We were celebrating my nephew's graduation from Ft. Benning before he ships out to Ft. Campbell. I will know in the morning though. I'll turn on the EBH about 1 & 1/2 hours before I leave for church and see what the temp looks like.