Best Place for a Heater

[Tiwaz]

My Humvee sits outside and we are going to get in the 40's on Friday, this is my only vehicle which I go to work with everyday, it has a VERY hard time starting in the 50's because very likely I have an issue with the Start Box and/or the glow plugs. Now my plan is:
I have electricity and a 1500W electrical zone heater that I can place Thursday night in the truck and the question is:
Am I better off removing the dog house and aim the heater towards the engine or is it better to put it underneath aiming upwards...?
In other words which is the best spot to place thew heater in order for it to keep the important starting components warm...?

 

[Coug]

What needs to keep warmer is the engine cylinders. You aren't going to do a whole lot with an external heater, but I would say going from underneath is likely going to do more for you than trying to aim through the doghouse opening with it's limited space.

As it's sitting outside, you're probably also going to want to drape something like a tarp completely over the hood section of the truck to help keep that warm air from just blowing away.



You might check to see if any of the local auto parts stores have magnetic block heaters, and use one of them.
Normally they are most useful for keeping oil warm enough to flow easily, but in your case it would probably help heat the engine block enough for a little easier starting, with less loss than your space heater. Might be able to put it higher on the block near the cylinders, but those surfaces aren't all that flat so wouldn't make the best contact, but still might work. Even if it manages to warm up a couple cylinders that makes it much easier to start overall.

Looks like Napa in Miami can have one ordered and shipped to store by tomorrow according to their website.

https://www.napaonline.com/en/p/KAT1160

Best would be installing a coolant heater. They are pretty common/cheap for the GM 6.5 block, but again, with your location, they might not be something you can pick up locally, and do require draining the cooling system to install.
Some engines already have the heater portion installed and all you need to do is buy a cord, but depending on which freeze plug they were installed in they might be very difficult to reach or even see if you have them installed. I just went out to my truck and can pretty much just see the two freeze plugs on the driver's side from underneath

 

[Mogman]

Where's J C Whitney when you need then, they had all kinds of do-dads for heating your engine.
The best would be a block heater that replaces a casting (freeze) plug.

 

[Mogman]

From what I can figure out it is a 1 5/8.

https://www.napaonline.com/en/p/KAT11614

 

[Mogman]

This is just to confirm they are 1 5/8"

Freeze Plug Block Heater- 1 5/8", 600w, 120v- GM 6.2, 6.5l Diesel (up to 2000), Gas 4.3, 5.0, 5.7 (Gen 1) (Zerostart 3100057)

Freeze Plug Block Heater- 1 5/8", 600w, 120v- GM 6.2, 6.5l Diesel (up to 2000), Gas 4.3, 5.0, 5.7 (Gen 1) (Zerostart 3100057) 3100057 Phillips & Temro

triplertruckparts.com

 

[KKroger]

You could use a circulating heater in the heater hose. 120V

 

[TOBASH]

My Humvee sits outside and we are going to get in the 40's on Friday, this is my only vehicle which I go to work with everyday, it has a VERY hard time starting in the 50's because very likely I have an issue with the Start Box and/or the glow plugs. Now my plan is:
I have electricity and a 1500W electrical zone heater that I can place Thursday night in the truck and the question is:
Am I better off removing the dog house and aim the heater towards the engine or is it better to put it underneath aiming upwards...?
In other words which is the best spot to place thew heater in order for it to keep the important starting components warm...?

Purchase a Webasto for diesel engines or just replace your glow plugs. Or insert a block heater.

 

[Tiwaz]

well I really did not want to start buying stuff since I do not face this problem on a regular basis (In Miami you see temp in the 40's every couple of years), I just wanted to know if there is any counter indication in placing a heater under the oil pan to bring the oil temp in the 60's, I think that should do the trick, right..?

 

[Thunderbirds]

well I really did not want to start buying stuff since I do not face this problem on a regular basis (In Miami you see temp in the 40's every couple of years), I just wanted to know if there is any counter indication in placing a heater under the oil pan to bring the oil temp in the 60's, I think that should do the trick, right..?

.
When my last box went out I tried something similar, I heated the garage to about 75 with a propane heater, and had a 1500 Watt infrared heater underneath for about 2 to 3 hours and it did not fire the truck up... So my guess is you can try, but I don't have much confidence. The oil may be warm, but you need the heat inside the cylinders or pre cylinder space.

 

[Tiwaz]

would then trying to start the truck with the space heater in the air intake (w/o filter) do the trick...? Maybe...?

 

[Coug]

Using a heater in the air intake won't hurt, but can't say if it will actually be of any real help. Warmer air should in theory help increase cylinder air compression temperature, but unknown if that heater will warm enough air to make a huge difference.
I do vaguely recall hearing about people using hair dryers down the intake to help engine starting, but don't remember the details and whether it was even diesel engines being discussed.

 

[Thunderbirds]

would then trying to start the truck with the space heater in the air intake (w/o filter) do the trick...? Maybe...?

.
Maybe, a better chance than with the oil pan warm alone for sure.

 

[Rescuediver1982]

While not an immediate fix, a long term solution would be the manual PCB modification to use the momentary push button and glow plugs. About $85 and I wouldn't think you would wear them out for quite a while.

Short term, tarp and under engine heater to warm the whole engine bay to create a closer to Miami ambient temp.

 

[Tiwaz]

While not an immediate fix, a long term solution would be the manual PCB modification to use the momentary push button and glow plugs. About $85 and I wouldn't think you would wear them out for quite a while.

Short term, tarp and under engine heater to warm the whole engine bay to create a closer to Miami ambient temp.

Sure man... I am all for building a bypass Start Control Box, I feel very comfortable with schematics and a soldering iron and i would prefer to build a separate gizmo vs. modifying the OEM one since while I build it I can continue driving my truck to work and back and then once I am finished I swapp it in an hour or so.
The problem is that I have not found a real schematic out there except some papers that look like the hieroglyphics from ancient Egypt with possible discrepancies.
Can anyone steer me in the right direction?

 

[Mogman]

Sure man... I am all for building a bypass Start Control Box, I feel very comfortable with schematics and a soldering iron and i would prefer to build a separate gizmo vs. modifying the OEM one since while I build it I can continue driving my truck to work and back and then once I am finished I swapp it in an hour or so.
The problem is that I have not found a real schematic out there except some papers that look like the hieroglyphics from ancient Egypt with possible discrepancies.
Can anyone steer me in the right direction?

What is the model and serial number of your truck?
Also I would advise picking up a junk box and modify it as you drive otherwise you will have to butcher your main wire harness and that is definitely not recommended.

 

[Tiwaz]

What is the model and serial number of your truck?
Also I would advise picking up a junk box and modify it as you drive otherwise you will have to butcher your main wire harness and that is definitely not recommended.

2007 M1151 A1 S/N 258870

Sure i'll pick up one of those (on eBay?)

 

[Mogman]

Try these

 

[TOBASH]

Sure man... I am all for building a bypass Start Control Box, I feel very comfortable with schematics and a soldering iron and i would prefer to build a separate gizmo vs. modifying the OEM one since while I build it I can continue driving my truck to work and back and then once I am finished I swapp it in an hour or so.
The problem is that I have not found a real schematic out there except some papers that look like the hieroglyphics from ancient Egypt with possible discrepancies.
Can anyone steer me in the right direction?

The definitive thread containing exactly those schematics is in my signature line in my profile.

Posted around 2018.

 

[Milcommoguy]

2007 M1151 A1 S/N 258870

Sure i'll pick up one of those (on eBay?)

Check your DM's from me.

 

[Dieselmeister]

I have a 500w block heater, and a 250W oil pan heater. I have found that the 250W oil pan heater does a better job than the block heater. Apparently the heat rises enough to keep everything warm and ready to start.