inline heater on a 86 K5

I have a 1986 K-5 Blazer 4X4 5.7L and I'm looking to install a heater I bought several years ago for a different truck. Its the type of heater the installs in line on one of the heater hoses. Since the box and directions were lost long ago does any one know which hose is supposed to be used the top going to the block or the bottom going to the radiator ? the heater is a thermo~pump 1500kw this is all the info I think I have any help would be great Derrick

Reply to
DoubleXL
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You are suppose to remove one of the drain plugs from block for the cold water feed to heater and the output from the tank heater splices into the heater hose output from block with a "Y" fitting in line with base of "Y" pointing toward the engine in heater outlet hose.

Reply to
TheSnoMan

There was nothing that cam with it to fit in the drain plug I thought it was used inline on the heater hose alone. no y pipe or plug came with it oh well it might be just another piece of junk I've had filling up my garage lol Derrick

Reply to
DoubleXL

Any hardware store will have the fitting to screw in your block drian plug. I have installer serveral of these over the years and I usually had to get extra parts (a elbow to screw into drain hole) to do it. It is not a big deal to find the adaptor. Below is a link to a company that still makes them today.

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Reply to
TheSnoMan

It CAN be spliced into the heater hose. To do it the other way means you have to drain the block. Might as well use a real block heater if you do that! Should have a check valve built in and it has to be mounted correctly to help the valve ball close properly. Flow through the heater core is in the direction to lift the ball from the seat when the engine is running. When in use, the in-line heater pumps in a reverse direction to that of normal flow. You want the heater to be mounted close to the engine and then it can pump to the engine, then to the other heater hose, through the heater core and then back through the spliced hose to the heater and REPEAT. A frost plug type heater is much better than one of the in-line kind but sometimes they are not so convenient to install.

I have never had to drain the block and install special fittings and a y but each to their own.

Reply to
The Nolalu Barn Owl

You never installed one correctly either. That is how they work the best as it takes water from the lowest and coldest part of block and return hot hot to top of engine to filter down. Any other way is a cob job and not very efficent. Been using them for over 20 year in different application where a in block heater is not viable.

Reply to
TheSnoMan

Been following the enclosed directions for about 30 years now. Installed the last one just last year on my tractor. Your way will work like you say but IF I have to drain the entire block I will ALWAYS chose to install a REAL block heater in the frost plug over those anemic pumps that splice into the heater line. We get -30ºF here in the winter and those pumps just don't cut the mustard. That is the real deal and my experience backs me up.

Reply to
The Nolalu Barn Owl

I never drian all od the coolant to do it with tank heaters. If you have your ducks in a row you may loose 1 to 2 pints doing it at most. As far as cold weather operatio, you have to size tank heater by temps and engine size and I have used them at near minus 50 and they did the job for me. You need to install tanker heater so the output is below (in height) on hot water input connectio to block and it help to mount it as close as possible in evelvation (tank heater input) to drain plug in block. I also wrapped the output hose frome tank heater in fiberglass insulation and the hose to the block to so maximum heat was sent to. A

1200 watt unit would warm a V8 at 40 below enough so that reliable starting was not a issue. They make some real serious 230 volt tank heaters too.
Reply to
TheSnoMan

-50?? The BS is starting to pile up here Snowman.

The drain for the block is low enough to drain the entire block hence the need to drain the block to install the fitting and get a leak free connection. The drain is the lowest point in the water jacket. I would have little chance of keeping insulation dry and able to stay as insulation (must be dry to be effective) since our winter has lots of slush and snow. The heater you describe wastes lots of heat before it can get into the engine just by the design of it. The fact that the heater itself is surrounded by cold air should be a clue.

230 volt heater? Fat chance of getting a plug-in at work with 230 volts.
Reply to
The Nolalu Barn Owl

No BS on the Minus 50, when I lived in Montana in mid 90's, monus 40 was no big deal and there were days it never got above minus 20 or 25. You also warp insulation with a plastic wrap to keep it dry. I works as I have done it. Also, I had on 4x4, a 4x4 burb with 2 block heaters becaue below minus 30, one does not do a very good job and with two you got normal starts and quick warmups. Not much heat is lost with a tank heat when installed as described earlier. Also I used a grill cover that was fully zipped up which added in preheat as well. The only real problem with tnak heater is that they need to be replace every few years because they tend to rust out unless you pay top dollar and get a SS one. here is a link for a sourge for engine heaters.

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Reply to
TheSnoMan

Yeah, we get cold weather here in Canada too but these days not as cold as I remember. Used to go to -40ºF for days at a time and now it hardly ever gets below -30ºF. Get plenty of wind chill at times but that is another animal.

You gotta love it. Quotes from that source:

- "FREEZE PLUG HEATERS The choice of professional installers ? Ensure quick winter starts - reduce engine wear ? Highest rated, most efficient type of heater"

After sifting through almost the entire catalog I finally found a few pages on inline heaters.

- "INDUSTRIAL TANK/CIRCULATION ENGINE HEATER offers dependable engine starts in all temperatures."

- "Many engines manufactured since 1977 do not have a coolant drain plug in the block."

I had a 75 Nova and it all of a sudden had trouble starting. After only 30 minutes with the inline heater on and a blanket over the engine it fired up easily only to fail after it cooled for an hour or so. I figured out that the blanket kept the heat from the inline heater from escaping and it heated the battery. Once that was figured out it became apparent that the battery had a dead cell. The inline heater on my tractor has the same deficiency. Cold air surrounds the metal can and cools off the heater as it tries to warm the antifreeze. I wait to see if the heater is working properly by holding my hand to it until I feel the heat. Don't forget that the inline heater circulates at much the same rate of flow as the average coffee maker and the hose is trying to cool off in the cold weather. A Frost Plug Heater puts ALL of its heat inside the motor while all the insulation in the world won't even come close to putting all the heat of an inline heater into the engine.

Same problem with those gimmick magnet heaters. At 200 Watts they have two sides. 100 Watts worth is touching the oil pan and 100 Watts is blowing away in the wind.

He will get a good install by cutting the heater hose and directing the flow to the engine - NOT to the rad and NOT to the heater core but that heater simply won't hold a candle to a Frost Plug Heater for performance ESPECIALLY DURING WINDCHILL conditions.

Reply to
The Nolalu Barn Owl

Thanks guys for all the help. That was the main problem trying to figure out which hose was doing what my blazer does not have a coolant drain on the block or at least not that i have found yet lol. It says on what instructions ive found most are very general that this type of heater will not work on all trucks and im wondering if a 86 k5 isnt one of them. Like i said ive installed the heater going both ways in the heater line that runs inbtween the head and the heater core. the other line is just the drain out of the heater core to the radiator. I dont think it would do much good to install it there. The tems just get down in the singel digits here anymore not much neg. anymore. but it still would have been nice to got it to hear up a little quicker when its 6 or 7 out lol. Merry Christmass To every one

Derrick

Reply to
DoubleXL

here is a link to heaters they use in large trucks

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apparently there's a large demand for Canadian trucks, due to the extreme temps. Looks like they make products for marine, automotive and other applications too.

Reply to
Elbert

There sure is a demand. We have started using them to reduce idling time on heavy equipment at my place of employment. Prolonged idling causes a buildup of carbon and eventually the engine fails when the valves come into contact with the carbon on the pistons. Wouldn't have believed it but I now do maintenance planning for the Garage at Bowater Paper Mill in Thunder Bay Ontario and this problem comes up time and time again. Can't remember the figures right now but the savings just in fuel consumption is considerable and amounts to thousands of dollars @ year for big loaders that work 24/7. Now, if we can just get the drivers to use it instead of leaving the engine idle.

Reply to
The Nolalu Barn Owl

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