I'm going to be installing a block heater. In addition to the standard freeze plug type, Napa has one that's 3/4" NPT. Anyone installed one of these or know anything about them? the description doesn't say where it goes, (well it says freeze plug...i don't think there are any threaded freeze plugs on these blocks) I was thinking this goes in place of the block drain plug? Funny thing is that this one doesn't come up in the options for a '99 5.4l. Current engine in the truck is a 2004 2V. Possibly just a catalog error (shocking!) maybe not though, does anyone know if there were any threaded ports added to the 5.4 blocks over the years?

 

Without seeing a picture, it is hard to guess, but, is it possibly what used to be called a "tank type" heater that is plumbed into your heater hoses? One thing about them, they generally came with higher wattage ratings and worked relatively fast.
Does it look something like this?

 

A NAPA part number would help us to help you.

 

This is the company that makes the block heaters for NAPA.
Which type do you use?

Kat's

 

This is the tank type heater that I used in my '72 Ford Supervan, I also had a rear heater in it. Lots of area to heat. It was 1500 watts and very effective.

When I bought my new van, I ordered it with a factory freeze plug heater, or, at least I think that is what it is, I've never seen anything but the cord, hanging out of the grille.

I think the 3/4 inch model may be one that fits in a hole on the top of the block, rather than a heater hose, or freeze plug.

 

Many other companies make engine heaters.


https://www.google.com/webhp?sourcei...gine%20heaters

 

you're likely supposed to change the freeze plugs to accept the heater.

 

Thanks for the replies. This is the heater in question:

Part No. 3100002, made by Phillips & Temro. This is Napa Canada by the way, I don't see this type on the US site. I doubt it its intended to be installed in a freeze plug, since this would require replacing the freeze plug anyway with one that had a threaded hole in it. One would just use the standard 1 1/2" freeze plug type of heater in that case. I'll report back if I decide to use this one, a closer read shows it's only 400w...

 

I was surprised to measure the one on my new F150 at 400W as well. Previous to this the only two vehicles I've had with a block heater were diesels, and those were 900W.

But it makes sense. Both Powerstroke engines were over 1,000 lbs, and the V6 in my new truck is just under half that. Your 5.4L engine weighs 525 lbs, so I don't think 400W is inappropriate for it.

 

I have found that 400w heaters work fine, but need much more 'on' time to heat and engine - like 6-12 hours, rather than 3-5.

 

I thought you were supposed to plug the heater in while the system was still warm so you don't wear the heater out by trying to warm up the coolant, block, transmission, and air in the engine compartment...

 

Removing a freeze plug and inserting a heater is a scary proposition to me. I went with one of the magnetic oil pan heaters. Seems to work just fine and much less work to use.

 

The owner's guide of the '12 Super Duty as well as my '15 F150 would assert otherwise.