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Topic: When should I turn on the block heater? (Read 1078 times) previous topic - next topic

When should I turn on the block heater?

Tomorrow afternoon is supposed to be the "warm" part of the week - 30* so I'm going to take the coach over to the dump station and dump and fill. Normally I turn the block heater on when we go to bed the night before a travel day, but then we leave right after breakfast, too. This will be different. Temperatures overnight are going to be in the single digits. Any problem with turning on the block heater at bedtime tonight and leaving it on all night and all morning?

Re: When should I turn on the block heater?

Reply #1 –
Nope  ^.^d
Andy & Eileen
MONTROSE COLORADO
1992 U300  40' 6V92 TA
2016 4 Runner
1998 Jeep Grand cherokee

1998 Jeep Grand Cherokee) Build # 4135 Skp# 122921

Re: When should I turn on the block heater?

Reply #3 –
My understanding is that the 6v92's as installed have a poorly placed block heater. 

Maybe a truck type engine heating blanket over the motor might warm to top end also?

I had a problem with fuel gelling out at that cold a temp.  Needed  the other diesel fuel for that climate with more kerosene in it.

May require extended cranking to build top end heat to start.  60 seconds is ok.  Then a few minute gap.  Then additional 60 seconds can be used.

Battery's will be low amperage at those temps.

Battery heaters used to help.

Another heating blanket over the start batteries might help the amps.

Hopefully you still have an operating oem ether start as all of the above may be needed.

Not sure but both the gen and engine probably have low temp oils available.
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: When should I turn on the block heater?

Reply #4 –
Warm batteries and a warm block, leave them on overnight, and bingo a happy start to the day in my view.
Speedbird1
2001 U320 Build #5865
Daihatsu Rocky Toad
VW Touareg
'82 F100 Stepside
Beech' Debonair

Re: When should I turn on the block heater?

Reply #5 –
I have the operating specs for the CAT 3116 block heater if anyone needs; hopefully not.  ^.^d
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: When should I turn on the block heater?

Reply #6 –
Your engine will only get as warm as temperature (outside) and size of heater will allow.  The temp. will reach an equalibrium at some point in time as determined by these values.  Plug in the heater the day before and see how long it takes to reach that equalibrium.  (you can use a laser thermometer) Any amount of heating after that is just to maintain the temp.  Good to know how long it takes so you can get it right the next time.  This is one of those things that is a little different for each coach set up.    Have a great day  ----  Fritz
Fritz & Kathy Johnson
1991 36'

Re: When should I turn on the block heater?

Reply #7 –
If your coach is newer.. hit the rocker switch for the Aqua-Hot- engine heat,not sure if all are plumbed to do this in addition to the electrical block heater..
'02 40' U320t  4010WTFS Build 6036 1 slide
Motorcade # 17841
SKP 151920
Retired truck driver
 5 million miler
Still have itchy feet for travel

Re: When should I turn on the block heater?

Reply #8 –
Plug In the heater tonight leave it plugged in and it should start just fine in the morning. Just make sur to unplug the extension cord if you use one before driving off...... ^.^d
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: When should I turn on the block heater?

Reply #9 –
Quote from: Caflashbob –
My understanding is that the 6v92's as installed have a poorly placed block heater. 
Bob,
Quite correct in most cases. In below freezing weather, the thermostat heater location will need to be on all night. If it's located down low on the block close to the AC compressor like a Bluebird, Wanderlodge or a few Foretravels, a couple-three hours will do the trick in really cold weather. The remote type heater that Ken installed will heat the block pretty quickly. It also depends on the altitude. High and cold make for longer heater use. At Yellowstone at 17 degrees in the snow, the generator needed ether to start even with all glow plugs working. The Detroit started without heat with only ether but took at least ten minutes and melted a battery connector.  The thermostat heater had burned out. Once it started, I couldn't get it above about 300 rpm for another 5 minutes with only half the cylinders firing.

I moved to the lower altitude Mammoth Campgrounds after that where starting was much easier.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: When should I turn on the block heater?

Reply #10 –
Quote from: fkjohns6083 –
Your engine will only get as warm as temperature (outside) and size of heater will allow.  The temp. will reach an equalibrium at some point in time as determined by these values.  Plug in the heater the day before and see how long it takes to reach that equalibrium.  (you can use a laser thermometer) Any amount of heating after that is just to maintain the temp.  Good to know how long it takes so you can get it right the next time.  This is one of those things that is a little different for each coach set up.    Have a great day  ----  Fritz
The above pure truth. Thanks Fritz!
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: When should I turn on the block heater?

Reply #11 –
Pierce,  a lot of members here have removed their ether systems. 
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: When should I turn on the block heater?

Reply #12 –
Quote from: Caflashbob –
Pierce,  a lot of members here have removed their ether systems. 
Unless you have been trained and can resist the temptation to use it on a hot engine that won't start, it's a good idea to remove it. I use a spray can of ether. Detroit 8V-71s were OEM with a little spring loaded cap above the blower to spray into. Just no big deal on a cold engine.

Pierce

Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: When should I turn on the block heater?

Reply #13 –
The oem ether start system has a built in thermostat restricting its use above 50 degrees F,  won't work
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: When should I turn on the block heater?

Reply #14 –
Quote from: Caflashbob –
The oem ether start system has a built in thermostat restricting its use above 50 degrees F,  won't work
Bob,
The OEM on our Detroits was just a tiny spring loaded cap that you used one finger to open it up and hold it open and the other hand to spray the ether in with.

P
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: When should I turn on the block heater?

Reply #15 –
Quote from: stump –
Plug In the heater tonight leave it plugged in and it should start just fine in the morning. Just make sur to unplug the extension cord if you use one before driving off...... ^.^d
  Quite a few years ago, the DW and I moved to Northern New York where winter temps can (and do) go as low as -20 or more.  The first winter we lived there some friends suggested I have a block heater installed in my car, which I did.  Well January came and we had a forcast of -20 for the overnight, and being a semi-intelegent person I plugged in the block heater, hooked up the battery charger on trickle, let the hood down to keep varments off the engine and went to bed.
  I swear I told the DW.  That's my story and I'm sticking with it.
  For some reason I don't remember, the DW got up first and decided to run an errand, gets bundled up and heads out to the garage and turns the key.  VROOM!  Car starts right up.  DW lets car warm up for a minute and puts it in reverse.
  (No, no she did not - don't get ahead of me here.)
  Backs up down the driveway - about 100' or so - turns the car around and drives forward down the remainder of the driveway.
  With the charger in tow.
  With the charger being dragged UNDER the car, down the road.
  With the charger being dragged UNDER the car, down the road, bouncing on the under carriage of the car.

  I still have that charger, a Sears, and it still works.
In restless dreams I walked alone.
Narrow streets of cobblestone.


'93 U225
Build 4337
'14 CRV Toad

Re: When should I turn on the block heater?

Reply #16 –
You can leave the block heater on all Winter if you're not paying the electric bill. I suspect you've probably got the water heater on top of the block like my engine has. It's semi useless in cold weather. Expect to have a difficult time starting your engine in very cold weather. A few Winters ago I installed an oil pan heater and discontinued using the block heater. My engine has never failed to start since then, no matter how cold the weather is. If the oil is warm enough for the engine to crank fast it'll start. My world record since installing the oil pan heater is three crankings to get the engine to start. On the first cranking the computer usually gives up trying after a few seconds if none of the cylinders are firing normally. The second cranking usually gets the engine firing normally on at least a few cylinders. After a few seconds all the cylinders are firing normally and the smoke stops. The engine is cranking at normal speed because the oil is warm. The engine itself doesn't need to be warm, just the oil. The block heater draws about a thousand watts and wastes most of the heat it produces through the radiator and top hose. It does little to warm the oil, so the engine's cranking speed is slow and starting is difficult in very cold weather. The oil pan heater I installed draws half as much power but puts a lot of heat directly into the oil pan, which allows my engine to crank at normal speed. The only variable is how long the computer will wait for some cylinders to start firing normally. The computer gives up after a few seconds in very cold weather but the engine almost always starts right up on the second cranking... Anyway, the oil pan heater is a super easy, inexpensive, very effective, and energy efficient modification that every cold weather diesel RV user should consider. I've tested mine thoroughly over the past few Winters and I'll never go back to the block heater, although it's still there in case of emergency. With the block heater turned on my engine would crank so slowly that it would fail to start in very cold weather and the cold oil was so thick that the cranking battery would run way down and I'd have to wait until it charged back up for another attempt. That's when I decided to make modifications.
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)