Ford IDI Diesel Fired Coolant Heater Plumbing (Webasto/Espar)

[wrangler9754]

Hello all, new here with a 1988 E-350 7.3idi ambulance. Was wondering if anyone has installed a Webasto/Espar diesel coolant heater on their idi; speciafically looking for the best spot to plumb the 5/8 lines from the boiler to the engine. I think one of the lines can tee into a heater hose? Where would the other go for best coolant circulation? Thanks, Glen

 

[Chorky]

I have been wanting to put one in my rig as well. I think you would like the idea of the inlet and outlet being a direct T inline to the heater hose itself. The only issue would be finding which side of the heater core (inlet or outlet) is what you want. I think it would be awesome to have it on the inlet side of the heater core, and have the blower motor have a secondary power source of the house battery so that when the wabesto is on, the blower motor can also be turned on in turn heating the cab and the engine... that would be pretty slick. Only issue is finding out which direciton the coolant flows through those two hoses...

 

[wrangler9754]

I have been wanting to put one in my rig as well. I think you would like the idea of the inlet and outlet being a direct T inline to the heater hose itself. The only issue would be finding which side of the heater core (inlet or outlet) is what you want. I think it would be awesome to have it on the inlet side of the heater core, and have the blower motor have a secondary power source of the house battery so that when the wabesto is on, the blower motor can also be turned on in turn heating the cab and the engine... that would be pretty slick. Only issue is finding out which direciton the coolant flows through those two hoses...

Thank you for your response. I thought about using the heater hoses, but i could see just the heater core being heated and not circulated throughout the block.. The direction of coolant flow is a) pressure inlet is via the hose on the "passenger side" head and b) the low pressure outlet is on the hose that connects to the top of the water pump.

It would definitely be beneficial to preheat the cabin as well, one of the companies advertises how you can wire your heater to do such!

I have preliminarily decided to attach the preheater into the passenger side block drain and run the outlet to the discharge heater core hose that goes to the water pump. This after watching some instructional videos made by one of the companies (forget which one), but I could be swayed.

 

[pgeering]

I am also interested in adding two water heaters to my 6.7 powerstroke. Looking for guidance on how to integrate these two heaters into the primary cooling loop. Anybody done this before on a powerstroke?
Phil

 

[dreadlocks]

If your wanting cabin heating a thermosiphon setup is not gonna be adequate, you'll need a circulation pump to get the flow rates needed for good heat, and then it dont really matter where you put it inline in the loop as the circulation pump will take care of that.. probably between the engine and heater core would be best place in flow stream for defrost/cabin heating.. thats where mine sits, but there's also a magnetic valve that isolates the engine and heater cores so I get cabin heating before it starts on the block heater.

 

[Chorky]

If your wanting cabin heating a thermosiphon setup is not gonna be adequate, you'll need a circulation pump to get the flow rates needed for good heat, and then it dont really matter where you put it inline in the loop as the circulation pump will take care of that.. probably between the engine and heater core would be best place in flow stream for defrost/cabin heating.. thats where mine sits, but there's also a magnetic valve that isolates the engine and heater cores so I get cabin heating before it starts on the block heater.

I thought these heaters had a circulating pump built into them?? also....assuming they are meant to handle the pressures of a cooling system, or do they need to be isolated. I know a lot of people use them but rarely see how people actually install them.

 

[dreadlocks]

I installed a webasto thermotop c into my vehicle earlier this spring, water pump is external.. I think some of the bigger bus sized ones do have water pumps but otherwise they just a heater, and they can handle pressures of the cooling system.. my system isolates the heater core on a smaller loop w/out the engine to produce heat/defrost quicker, I get heat coming out the vents in about 5-10mins, with the engine in the loop it takes about 30-45mins because that engine has alot of cold mass.

 

[Chorky]

I installed a webasto thermotop c into my vehicle earlier this spring, water pump is external.. I think some of the bigger bus sized ones do have water pumps but otherwise they just a heater, and they can handle pressures of the cooling system.. my system isolates the heater core on a smaller loop w/out the engine to produce heat/defrost quicker, I get heat coming out the vents in about 5-10mins, with the engine in the loop it takes about 30-45mins because that engine has alot of cold mass.

Bumping this thread. Considering a thermotop C in my OBS ford. With the factory spare tire jack removed in the engine bay, it seems the perfect location for a heater. According to the fact sheet (https://www.webasto-comfort.com/fil...m/EN_US/Datasheets/Thermo-Top-C_SpecSheet.pdf) the heater includes an integrated water pump.

So the questions:
can the heater/pump just be inline with the heater core hoses?
Will the heater/pump, when off, and the engine running, restrict flow to the heater core significantly?
Anyone know the direction of flow through the heater core? One of the hoses goes from the core, to the t-stat but before that has a T that also goes to the radiator?
Is it reasonable to consider running the thermotop C off the main vehicle batteries for pre-heat? Don't yet have a 'house' battery.
How long, in say 0 degrees, would preheat need to run to bring the engine up to, say, 75 degrees for easier starting

 

[twodollars]

Are you looking to use the webasto as a cold weather starting aid? That's what they were designed for. Spent some years plumbing them on hmmwvs, and the quicker heating time was nice, but a side benefit. On a idi engine, if cold start assist is the idea, plumb it to circulate through the cyl heads. Of course an electric block heater would be easier if that's the goal.

 

[Chorky]

Are you looking to use the webasto as a cold weather starting aid? That's what they were designed for. Spent some years plumbing them on hmmwvs, and the quicker heating time was nice, but a side benefit. On a idi engine, if cold start assist is the idea, plumb it to circulate through the cyl heads. Of course an electric block heater would be easier if that's the goal.

Yes, as a cold weather starting aid. I have a 7.3 DIT (OBS). Just steeling this thread instead of creating a new one....and couldn't find my own old thread on the topic. The idea is to warm up the engine, but also warm up the cabin. Block heater works, but the truck still doesnt' like sub zero temps. And of course having a shore plug when out camping doesnt work well ha.

 

[twodollars]

I am not familiar enough with a 7.3 to help with plumbing, not some more free input. These systems use battery power for the ignitor and the pump, so you will have less power available for your glow plugs a d starter motor when you actually start the truck. Finding that balance of heater on time for a clean start may be part of the puzzle when at cold ambient. Changing to a synthetic 5w 40 is also helpful in my experience.

 

[Chorky]

I am not familiar enough with a 7.3 to help with plumbing, not some more free input. These systems use battery power for the ignitor and the pump, so you will have less power available for your glow plugs a d starter motor when you actually start the truck. Finding that balance of heater on time for a clean start may be part of the puzzle when at cold ambient. Changing to a synthetic 5w 40 is also helpful in my experience.

I'm thinking more likely than not I will have to run a third AGM battery in the bed and run it off of that to allow the glow plugs and starter all the amperage - might also consider heat pads for the batteries too.

 

[Chorky]

Finding some answers to these questions - FYI for other inquiring minds:

Relating to the Webesto Thermo Top Evo:

Can the heater/pump just be inline with the heater core hoses?
Yes, it is designed to be in-line with the heater core hose, suggested install to be on the return line to heat engine first and heater core second

Will the heater/pump, when off, and the engine running, restrict flow to the heater core significantly?
Not significantly. The integrated pump is a magnetic design and freewheels when not engaged

Anyone know the direction of flow through the heater core? One of the hoses goes from the core, to the t-stat but before that has a T that also goes to the radiator?
Looking at this this weekend

Is it reasonable to consider running the thermotop C off the main vehicle batteries for pre-heat? Don't yet have a 'house' battery.
Rated running amps at <5, start-up pull may be 10

How long, in say 0 degrees, would preheat need to run to bring the engine up to, say, 75 degrees for easier starting
Unknown variable, according to tech support the Evo has a maximum run time of 2 hours. Once water temp reaches 168 degrees F, the heater will throttle back until the internal timer ends. If the 2 hour mark is reached before the temp is at 168, the heater will still turn off. With a smart controller, multiple heat sessions could be timed back to back. Likely engine would be heated within 30 minutes at 0.


Other thoughts:

I do not know, but would like to assume, that these specs between the Evo and C are identical, or miniscule enough to not matter.

It was noted that pre-heating the engine, 'could' cause a check engine light or fault code if the engine detects a temperature difference. For purposes of the 7.3, I don' think this is the case, and believe that the PCM detects engine temp via one single temp sender, which sends signals to the gauge cluster, and PCM for glow plug operation. This fault code seems more likely with computerized engines.

It was also noted the 'max' elevation for frequent and continual operation is 5,000. This obviously is a problem for 'overlanders', or anyone who live/operate above said elevations. According to tech support, the heater will work just fine above 5K', but only not at optimum efficiency. It should not throw any codes, or have a catastrophic failure. Although it was said if one lived above 5K and only operated above 5K that might be a different story - I happen to live at 4K, so it 'should' be ok. You can make some fine tune adjustments via the programming, but that is not really advised.

Also, Webasto ONLY sells through authorized dealers and not online. Apparently there is a huge issue with fraud going on with people buying 'Webasto' products that are copycat's and not the true product. They advise using the authorized dealer link on their site as other copy products assumed to be true are failing, and obviously not covered under warranty.

 

[pgeering]

Thanks for all the valuable information. Please keep us updated on the actual installation. What size is your planned unit again? And why Webasto and not Espar?

 

[Chorky]

Thanks for all the valuable information. Please keep us updated on the actual installation. What size is your planned unit again? And why Webasto and not Espar?

The Thermo Top Evo is about 9 L, 4 W,6 H. I'm sure it can sit sideways. I honestly don't know that I have a preference or reason between Wabesto and Eberspacher. A few years ago I tried contacting Espar and was not able to get very much decent information from them at all. The closest dealer I believe is, well, several states away. Last week I spoke with someone at Wabesto and they offered tons of info right away, were easy to talk with, and informative. They also happen to have a authorized dealer 30 miles away. I'm sure the performance of the two are comparable, but someone else here can probably speak more on that. I will say that Wabesto heater has the water pump integrated with the heater, and Espar has the water pump as a separate unit. That seems to me to be a nice feature to have an all in one unit.


After starting my truck today for the first time in a week (lots of travel for work) and sitting in 15 deg. temps, I'm certainly going to have a heater added, hopefully before new year.