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MDX Block heater option-help!

6437 Views 11 Replies 6 Participants Last post by  Pierre
Does anyone have the MDX block heater option, ($89). I have it installed and I am trying to figure out if it works.

I plug it in overnight then start the next day. The temp gauge seems to come up maybe a 1/2 mi before it normally does which could be the difference in the outside temps from one day to the next. I have been carefull to drive the exact route and speed each time. Tried plugging it in for 36 hours straight. Temp gauge comes up maybe a mile before normal, again, maybe due to the differences in outside temps from one day to next.

Dealer is no help. Mine is the only one they have ever installed. Reg. Rep. supposedly contacted by the dealer has never responded. In past experience with block heaters they warm the engine coolant much more than the Acura one, (if the thing is working at all??). Can't locate where a possible fuse would be either.

Anyone else have one, and if so, does it not heat up any better than mine???

Thanks!
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Do you work anywhere that there are maintenance electricians? Have one of them check the current draw when the heater is plugged in. If it draws less than 1/2 amp, you might have a problem. Then again, I don't know the rated wattage for the unit -- but it would surprise me if it were more than 100 (maybe 200) watts [or about 1 or 2 amps].
Block Heater

What temperatures are you talking about? I know that my heater does not come on until the engine block gets to about -18C ( -4F or something like that )

ANything above that and the engine really doesn't need the heater, so doesn't run it. ( keeps from drawing power unnecessarily)

Can Anyone from ALberta verify this also ( seeing as we've got a lot of use from them over the past week.)
:eek:
frostyra said:
Do you work anywhere that there are maintenance electricians? Have one of them check the current draw when the heater is plugged in. If it draws less than 1/2 amp, you might have a problem. Then again, I don't know the rated wattage for the unit -- but it would surprise me if it were more than 100 (maybe 200) watts [or about 1 or 2 amps].
We don't need no stinkin' 'lectrician.
Just buy this cool device Watts Up?. It is a monitoring tools that will show the instantaneous current draw, cumulative kwh (has built in timer) and cost to operate. It's around $90 and one of the cooler Father's day presents I've ever received (ok, I admit that's pretty geeky)
block heater

I don't have access to any maintenance electricians but that is a great idea.

The Watts Up tool looks like a good idea too. Maybe something along that line at the hardware store??

As far as outside temps. In the last couple weeks when I have been experimenting w/ the block heater it has been a bit below zero to about 10degrees above. I would think that this little unit does not have the intelligence to shut off or not come on if temps are at a certain range. It is a small unit that fits in the engine block plug and wire right to the grill where you plug in. Very basic. Regardless wouldn't it heat to a certain degree, (resistance built into the unit), no matter what? Maybe this unit is SO basic that they don't give it too much capacity so it doesn't overheat??
As far as my Basic understanding is...

The block Heater does not work when the engine is "warm" ( a relative term) So after you shut your MDX off and plug it in your block heater will not be functioning.

When your vehicle's block does get cold ( IE were talking temps of below 0 degs F - which is here in Edmonton, really not that cold ) then the block heater is needed and will kick in. ( the On/off works on the basis of metal that expand/ contract with varying temperature to complete the electrcal circuits.) Similarily when the block gets "warm" ( But not operating temperature) then it goes off.

SO try this, let the X cool off on a cold night. ( two or three hours in sub zero temp) then plug it in. What you will here is a bit of hissing sound - the same sound you get when you plug in a kettle and the water starts to warm. That's the BH working.

Remember, the premise of a BH is not to keep your engine/coolant at operating temperture so you get instant heat, but rather, to keep the engine block warm enough so that the engine will turn over and start in extreme cold. ( way colder than what your describing)

I think your concern about the BH not working is because maybe it's not cold enough there. ( yes it can get colder )

Can any other Canadians back me up on this?

Just to reassure you though, in Edmonton over the past week, we have nighttime temps of -33C ( -15F ) on the MDX's computer, and I've left it unplugged over night. Started with just a little bit of coaxing, and warmed up just fine in a few minutes.

Hope this helps.
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Naimdxer,

As far as I know, the block heater start working as soon as you plug it in that is why for the energy conscious people put it on a timer and have it start 2 to 4 hrs prior to when you need to start the car.

Also, the factory installed block heater usually only put out enough heat to keep the oil from getting too thick from the cold. This type of block heater does not make too much of a difference as to how long it takes for your car to heat up.

If you are interested in having your car put out some sort of heat as soon as you start the car than you will need the heater that fit in your coolent hose. These type of heater will heat and circulate the warm coolent thru you engin. (EVEN than don't expect too much heat).

That is my $0.02 worth.... by the way I am from Winnipeg, Calgary even thou I am in San Diego now and will never need a block heater. :p
Naimdxer,
Thanks for the insight. I think the heater is ultra basic. It must be on all the time it is plugged in but as you say, doesn't put out much heat, just enough to keep the ability to flow oil at low temps. And, true, my temps don't approach anything like you guys have! I would guess then that the low output means it runs, (heats), all the time it is plugged in but can never heat up the coolant anywhere near operating temp or even off the lowest white mark by the "C". Could be there is a thermostate but I doubt it by the installation instructions the dealer gave me with the unit.

Guess I really need to experiment at differnent engine temps and determine if it draws the same current regardless. Now all I have to do is borrow some kind of tool like the "Watts up" thingy that donsev mentioned.

Thanks for the input everybody!
Our block heater is not really a block heater but an oil pan warmer. As pointed out in a previous post, its role is to keep the oil tepid enough that it will reduce the resistance when the engine rolls over on a cold start.

My X sleeps in the garage, so haven't needed to plug it in, although we've had some pretty cold nights. If it's anything like my Altima, which sleeps outside, the "heater" won't kick in until the engine temp reaches a certain threshold -- about -18C (0F) I've heard the "hissing" sound described above, proof that it works, and have noticed that the engine does warm up faster when it's been plugged in.

I also use a timer to ensure that the BH doesn't work unnecessarily. Three hours is all it needs.
Pierre

Are you sure it warms the oil. I am pretty sure that the heater is installed in one of the expansion plugs in the block which is in contact with coolant, not oil. I have the dealer installation instructions, I will look up.

RE: 3 hours sufficient to warm. Thanks, I was going to experiment with lenght of time to plug in. this saves lots of time.
Block heater heats the coolant

Checked the supplied (by the dealer), acura installation instructions. They say that the block heater element is installed in stead of the block coolant drain plug. So the block heater does heat just the coolant. (Indirectly heats everything around it like the oil I guess).

Anyway, appears to do a minimum of heating and has no thermostatic control mentioned in the specs, nor does it have a fuse!
Re: Block heater heats the coolant

Tahoe4wd said:
Checked the supplied (by the dealer), acura installation instructions. They say that the block heater element is installed in stead of the block coolant drain plug. So the block heater does heat just the coolant. (Indirectly heats everything around it like the oil I guess).
I stand corrected. Thanks, Tahoe, for the update. One of these days, I'll learn not to ask the dealer about things mechanical....I'll ask his service guys instead!
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