Circulating heater install on 1HDT

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Looks like a nice install. Almost identical to mine.

The 750w will be borderline for you. I opted for the 1.5kw version and it works hard when it gets below -25.

Keep checking for trapped air in your coolant system. It took me a few days to get all the bubbles out.

Sent from my Android shoephone using IH8MUD
 
Well, I've officially started this install! Thought I'd get a jump on it tonight and got the block drain removed, and the fitting from the heater kit installed. I removed the drain as one piece, the larger insert is a 15mm I think, and a deep socket slides right over the 10mm plug, so that made it easier. I made a plug from a bolt head, piece of 5/8 hose, and a clamp so the coolant doesn't drain overnight, and I'll finish it up in the morning. Didn't seem to lose much coolant either.

Does anyone have pics or a description of what they mounted the heater bracket to? Were you able to maintain 3" clearance all around? I think I can mount it to the strut tower, but I'd love to see/hear what others did.
 
Sorry, no photos besides the ones in this thread. But I bolted directly to the shock tower. Some have used the frame rail. Just make sure it is as low as possible.

I do have 3" clearance from any wires or hoses.
 
Got it finished today, it's running in the driveway to get the air bubbles out, and make sure there are no leaks. Looks like I only lost about 1/2 liter of coolant putting the fitting in the block last night, so that's good. Getting the fitting into the drain hole in the block is 1/2 the job easily. Thanks to finderscuba and those who contributed to this thread, it was VERY helpful!
 
Got to test it out today at work, there was heat in the hose from the top of the heater to the firewall within 30 sec, and when I came out at the end of the day the upper rad hose and top of the rad were warm. Truck started easily, temp gauge came up, then went back down until I had driven a ways. There was an air pocket that could be seen in the plastic Y-fitting before I started it, so I've got to get that out of there.
 
Hey Ian,

How's it working for you in these colder temps? Did you manage to get all the air out of the Y fitting?
 
finderscuba said:
Hey Ian,

How's it working for you in these colder temps? Did you manage to get all the air out of the Y fitting?
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I took it out and climbed some snow banks the other night to get the front end elevated, and revved the engine up a bunch and topped up the system. I haven't seen air in the Y since. I only plugged it in at lunch yesterday, and the engine started quickly, but the temp gauge didn't budge, and it took some driving to get the temp up.

Today I plugged it in right when I got to work so we'll see how it does. I've got to run out at lunch so I'll have a look then, as well as after work. I'll know more after today.

Edit: looks like I still have some air in the system, as I can see a pocket at the plastic elbow. What's the best way to get this system bled? Elevate the front, then what, rev the engine for a while? Or is there another trick I could try?
 
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My heater block started to leak and good time to on install my the new Kats 120 volt, 1500 watt tank type heater on 1991 1hdt Vx. Keep everyone posted on progress, going to get cold here in Toronto next week.
 
Pictures of heat Circulation installation, was not able to connect to block drain as the hardware came in with kit did not have the right size, so ending connecting to lower hose. It is successes, tested last night when was -7 deg, and heat up the truck in 30 minutes. I am very amazing how easy the truck started and get heat right away, no air in system. Want thanks everyone on info

I used a Kats P/N 13100, 120 volt, 1500 watt tank type heater.

Third Picture show drain plug and hardware plug from the kit
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Happened to go out to my truck this afternoon to drop some stuff off, figured I'd pop the hood to see how the heater was doing on the coldest day of the year to date (high of -26C, feels like -38), and I was disappointed to find the engine and all heater hoses were stone cold. Went and grabbed a co-worker's extension cord with a light in it and confirmed there was no power to the plug-in. Alerted property services, and went to move the truck around to another plug in that was working for the last hour of the day.

Truck did not like this, started rough, slow to respond to throttle inputs (doesn't want to bring the revs up when given gas, once it catches it's fine again), wanted to stall. Got it moved and plugged in though. Started it at the end of the day, took a lot of cranking and some gas pedal, got it running and set the hand throttle around 1300rpm for about a minute, and started to slowly drive. Even after the temp needle had moved off cold, the truck idles real low and wants to stall. I ended up having to slip in in neutral and keep the revs up a bit at stoplights to keep it from stalling. Did this for about 10min of driving, then smartened up.

I'm ordering some new glow plugs tonight to see if that helps. Does this sound more like a glow plug issue, or a fuel gelling issue? This is the same way the truck was running when I had problems at Christmas time, no fun messing with stuff when it's that cold out.
 
I had same issue when I fill out diesel from unknown gas station about three weeks ago, now I used V-Power from Shell, also used Sea Foam. No problem at all.
 
I say fuel. Time for a Walbro!
 
hi guys, I've been reading this thread with interest, I am rebuilding my 1HD-T due to a spun bearing, but before that happend I orderd in everything to do a UVO install. I was contemplating installing a tank heater for faster switch over to UVO and based on these results, seems like the way to go. 3 Years ago I put a heater in the lower rad hose, that worked like a bag of dogy doo, warmed up the RAD more than the engine. I will use the ACD inlet outlet to heat my UVO flat plate heat exchanger and filter. Ill use the draincock and heater inlet hose to splice in the tank heater. My only concern with this setup is ; are we changeing the flow of coolanrt in any way that could affect the engine coolant flow negatively? . I.E, the engine was not desinged to run with coolant flowing out the draincock to the heater and back into block. Just a small concern.
This may be why some have indicated a decrease in cabin heater output with such an install, I would inmagine that the draincock being low in the engine water jacket will have cooler temp than what comes off the normal heater outlet ( higher up ). So in a sense when running, we are mixing cooler fluid with the flow intended for the heater. As a one post sugested, putting a valve to only open this circuit when the tank heater is on is probabbly the best practice.
 
A bit of an update on my issues with the power supply at work, the building maintenance guys pegged MY truck as what was blowing the circuit, I was hoping they were wrong. I heard 3rd hand that they saw sparking when plugging my heater in and unplugging it. I figured "Ya right, OK buddy" kind of thing.

Happened to glance at the cord in my backseat while running some errands today and something caught my eye, my new extension cord had brown marks on it! Took a closer look, and they were all along the entire length! This was a new cord last week, a 16ga, outdoor use, block heater cord.

I have now replaced it with a 14ga that is rated for 1875w. I got home and had a look and the cord I have under the hood running from the heater to the front bumper is a 16ga, but has a sticker showing a rating for 1625w, more than the heater's 1500w rating. Think I'm good keeping my current setup, or would I be a fool to leave the 16ga cord underhood after what happened with the last one? FTR the underhood cord looks fine currently, no brown marks or anything like that.
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Warning!

I went out to my truck after work yesterday and found steam coming out from under the hood. Opened it up and there was coolant everywhere, and the circulating heater was bubbling away. The plastic "Y" fitting has a split in it again.

At this point I'm not sure if the fitting split first causing the spray, or if the heater failed ON causing too much heat splitting the fitting. Right now I've got some heater hose over the split with a clamp to keep the coolant from spraying out until I can source a new fitting. I'll check NAPA at lunch. Then I'll have to see if the heater thermostat is working properly or if it is just staying on. Since I'm already on my second plastic fitting, I'll be looking for a metal one, or at least carry a couple of spares with me.

It took about 6L of coolant to refill after the leak yesterday.
 
Another warning

My heater has been working great so far this winter. Even at -30°C I was getting 25% reading on my temp gauge after having it plugged in for 3 hours. BUT, 2 days ago I charged up my batteries and noticed that the hose coming out of the heater was cold. The heater was not only dead, but the cord plug at the top of the heater was all melted, taking the contacts out as well. There's no repairing this, so off to the store I went to pick up a replacement. It only took 30 minutes to swap in the new heater and I'm back in business. But I'm a little worried that the old heater melted so badly!
 
finderscuba said:
My heater has been working great so far this winter. Even at -30°C I was getting 25% reading on my temp gauge after having it plugged in for 3 hours. BUT, 2 days ago I charged up my batteries and noticed that the hose coming out of the heater was cold. The heater was not only dead, but the cord plug at the top of the heater was all melted, taking the contacts out as well. There's no repairing this, so off to the store I went to pick up a replacement. It only took 30 minutes to swap in the new heater and I'm back in business. But I'm a little worried that the old heater melted so badly!
Click to expand...

Did you replace with another 1500w after the melting damage?
 
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