How to install a tank type coolant heater on the HDJ81?

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Laurentians North of Montreal, QC
Hey Folks,

I've been trying to find out how to install my tank heater for weeks. I've even PM'd one of you who apparently had installed a similar heater, to no avail, guess you were too busy.

I would LOVE to hear from anyone who has sucessfully installed one of these heaters on the 1HD-T engine setup in the HDJ-81. I don't want to butcher some pipes to find out I'm on the wrong hose. Can't find any cooling system diagram either...

The heater is sitting around waiting and the weather's getting colder...

HELLLLLP!

Chris
 
i've purchased one and trying to figure how to install it.:mad: i gived up and return it and brought home a lower rad hose heater instead.:) i've got a stinking feeling you're about to do the same, lol!!! :grinpimp:
 
Same here (with a 2B engine). I didn't like the look of the install, especially with the return hose having to go over the engine... etc. I returned it and for the price walked away with a freeze plug heater, two gallons of new coolant, and $12. :-)

Everyone here in Extreme cold seems to use the lower Rad heater. I'd do it but I have more experience with the Freeze plug style.

K
 
Thanks for the input, guys, but I really want to install that heater because I believe it has great potential for much increased heat output with the help of a recirculating pump.

Actually, after having examined the heating element, I am certain I could easily get 6KW out of it with nothing more than using 240V instead of 120V and a recirculating pump to move that heat out of the element to the engine block.

A poor man's electric Webasto, if you will.

Anyone who's installed a Webasto Heater on an 1HD-T that could give me some pointers? Pretty Please!

Chris
 
Chris,
if you have any specific questions please ask away... i did think the thread gave pretty good instructions though...
 
Chris,
if you have any specific questions please ask away... i did think the thread gave pretty good instructions though...

OK here's my problem: which way is the coolant going in the heater core? The problem I have is that the cooling system seems very unorthodox in this truck: the thermostat is on the lower rad hose, for example. I find it quite confusing...

There is a lengthy post on the canister heater installation that I was referred to, in which Bruce Lowen essentially says:

Simply figure out which way the water is moving through your heater core and plumb the heater in series with it

Problem is, I can't figure out which way the coolant goes!!! Where in the world can I find a coolant circuit diagram for the HDJ81?!

Anyway... I'll try to figure it out myself. I suppose if it's intalled wrong, the worst that can happen is that I won't have any coolant circulation in the heater. Will look into in in the next few days.
 
do you have a HDT engine manual? if not then purchase one. part number: RM172E.
page CO-2 shows the coolant flow patterns.
theline you want to tap into is the one from the block to the heater core then back to the block. the coolant flows from the lower block up to the heater core then back down to the head. you want to plumb the wabasto so the water feed is from the block into the heater then out of the heater up to the hear core. this is also the lowest spot on the block for coolant pickup...
HTHs
(i wasn't sure what you were looking for, i hope this is the information you needed)

cheers
 
do you have a HDT engine manual? if not then purchase one. part number: RM172E.
page CO-2 shows the coolant flow patterns.
theline you want to tap into is the one from the block to the heater core then back to the block. the coolant flows from the lower block up to the heater core then back down to the head. you want to plumb the wabasto so the water feed is from the block into the heater then out of the heater up to the hear core. this is also the lowest spot on the block for coolant pickup...
HTHs
(i wasn't sure what you were looking for, i hope this is the information you needed)

cheers

Well that clarifies it a bit. Unfortunately I don't have a factory manual. One of the things I'll have to get (would rather get a CD-ROM version and rpint out the page I need as I tend to destroy everything paper based - if you could post the page illustrating the coolant flow, that is all that I'd need for now!)

You say the coolant flow goes from the lower block to the head? Is that the normal flow direction? I would have expected the coolant to come out of the pump then to the heater, like on the 3B... Sorry if I can't understand the thermodynamics of the cooling system without a diagram!!!

In any case, my concern is that the heater I want to install has a one way valve, to force convection circulation from bottom to top. If the normal flow pattern while the engine is running is from the block connection to the head, no problem, as this is identical to normal convection.

If that is the case, then my question is answered and I can simply install that heater the same way you did the Webasto, case closed.

Can you confirm?

Thanks! I'd like to do that today before the cold spell sets in (I don't have a garage)

Chris
 
i do not know how to post up the page sorry...
confirmed, from lower block to heater core to head...hot water rises...
 
In my experience tank type heaters cause broken heads.

Interesting... By excessive localized heat, perhaps? I was concerned about this possibility...

A circulating pump will mitigate that risk. Install it exactly like Crushers installs his Webastos.

OK - If I understand correctly then, the Webasto does have a recirculating pump (I intend to install one as well), but what about coolant circulation when the pump is not operational? Is there some sort of bypass on the Webasto to allow natural flow when the Webasto heater is not in operation?

Thanks for your input, it is much appreciated, hope I'm not too much of pain with all my questions...

Chris
 

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