robp823 Posted November 26, 2008 Share Posted November 26, 2008 This might seem like a stupid question but is there any electrical test you can do to verify a block heater and cord is good besides just plugging it in and waiting to see if the block gets warm Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted November 26, 2008 Share Posted November 26, 2008 Yes, and it's a good question, not a stupid question. I generally hook it to an extension cord and listen at the connection for the "arc" of a circuit connecting passing amperage. It's all about amperage- if amperage is there, the heater is good. You could get creative and use an amp clamp to verify the wattage if you want, but they're usually either "good", or "open". I forget the wattage rating- I'm thinking it's 1000 watts or 1200 watts or something. If it's 1000 watts it would draw about 8 amps, and if it's 1200 watts it would draw about 10 amps. If you use a clamp-on amp clamp, make sure you separate the wires and not clamp both the hot and neutral in the clamp together. If you do that, the magnetic fields will cancel each other out and you'll get a zero reading on the clamp. You can also check it with an ohmmeter to make sure it's not open. Once again, I don't remember the ohm reading, but I'd bet it's only a couple of ohms. I like checking amperage better, it's much more accurate. Good Luck! /forums/images/%%GRAEMLIN_URL%%/grin.gif Quote Link to comment Share on other sites More sharing options...
mlee Posted November 26, 2008 Share Posted November 26, 2008 you can also just do a quick resistance test. most block heaters are in the 18-30ohm range. we also built a block heater tester out of an old trouble light. it plugs in series between the block heater and the wall outlet. if the light lights up, everything should be good. Quote Link to comment Share on other sites More sharing options...
DwayneGorniak Posted November 27, 2008 Share Posted November 27, 2008 We have a block heater tester like that too. But I sometimes just use a 12 volt test light. Hook the alligator clip of your test light to positive on the battery and ground on terminal of the block heater cord to metal on the vehicle and stick the pointy end of the test light into the other terminal of the block heater cord. If your test light lights, then you have continuity. The test light won't be extremely bright though due to the resistance in the block heater. Quote Link to comment Share on other sites More sharing options...
robp823 Posted November 27, 2008 Author Share Posted November 27, 2008 wow thanks for all the great info thought i was gonna get wow this kids an idiot ahahahhaha thanks again Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted November 27, 2008 Share Posted November 27, 2008 thought i was gonna get wow this kids an idiot Not Here! We might fuck with each other once in a while but we aren't fucking around @ the DTS! Quote Link to comment Share on other sites More sharing options...
DwayneGorniak Posted November 27, 2008 Share Posted November 27, 2008 The problem with a multimetre is you can have only one or two strands of wire making contact in a block heater cord and still get a good resistance reading. Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted November 28, 2008 Share Posted November 28, 2008 I have used the modified trouble light for about 20 years. I refuse to use anything else.... At the very least, you are subjecting the circuit to at least 1/2 of it's design conditions... and doing it as safely as you could ever hope for... However... if you are looking for something more conclusive (though not as convenient), try these suggestions... First. With the engine cold, plug the heater in.... after a couple of hours, listen closely for the "sizzle". You should be able to hear the element heating the coolant. If you are like some nameless old farts and have the benefit of a condition known as "tinitis" - you can get a bit more crude... With the engine cold, plug the heater in and wait a while... a couple of hours, again, is plenty. Slide under the truck and <GASP> feel the block heater.... For this item (well, for most items) the ohm meter is a fools errand... Turn your DMM to ohms.... place one thumb on each lead. Remember the reading... Lick your thumbs and repeat the test.... Now... what is it we were measuring? Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted November 28, 2008 Share Posted November 28, 2008 after a couple of hours, listen closely for the "sizzle". You should be able to hear the element heating the coolant. If you are like some nameless old farts and have the benefit of a condition known as "tinitis" - you can get a bit more crude... With the engine cold, plug the heater in and wait a while... a couple of hours, again, is plenty. Slide under the truck and <GASP> feel the block heater... Who the fuck has a couple of hours to test a block heater, and just what does that pay on flat rate? Usually the customer is standing right there and you need a "Yes" or "No" answer in 30 seconds or less. I'm envisioning Jim sitting in a lawn chair in front of the truck waiting to see if the block becomes warm...... /forums/images/%%GRAEMLIN_URL%%/laugh.gif Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted November 28, 2008 Share Posted November 28, 2008 I'm envisioning Jim sitting in a lawn chair in front of the truck waiting to see if the block becomes warm...... The only time I can envision Jum sitting in a lawn chair he has a tall iced glass of Coke and rye in his hand. Quote Link to comment Share on other sites More sharing options...
LARRY BRUDZYNSKI Posted November 28, 2008 Share Posted November 28, 2008 Quote: The only time I can envision Jum sitting in a lawn chair he has a tall iced glass of Coke and rye in his hand. No I think you have that wrong Keith, It's Rye and Coke and I believe his mix ratio is 3 parts Rye and a splash of Coke and don't forget 2 cubes of ice. He doesn't need more ice than that up there by the North Pole. BRRRRRR /forums/images/%%GRAEMLIN_URL%%/cheers.gif Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted November 29, 2008 Share Posted November 29, 2008 Larry is pretty close with the ratio... Ice? Why? It only dilutes the booze... Now, I realize that some of you guys are just "funnin'" with some of this thread... Consider this.... Every year, it seems that winter takes a LOT of folks by surprise.... "<DUH>.... it's Nuvemmmber an' all a sudden it gots cold.... How cummmmm?". Bruce.... there comes a point in time when we make a conscious decision.... Winter is coming and we are going to make the switch from summer oil to winter oil..... When we begin that switch, we also begin to perform other services as part of the package... remembering that every year for almost 60 years, winter happens.... we perform tests... One of those tests includes the use of a modified test light.... Or did we forget "I have used the modified trouble light for about 20 years. I refuse to use anything else.... ". However, other tests are rewarding - if not slower.... None include the use of an ohm-meter... an over -rated tool. If your customer shows up and buys a "service package"... all is good. You will have realized that winter fucking happens and wont be surprised by it. If your customer shows up and only wants his block heater checked - give you head a shake.... If this guys is really your customer, you will have already checked his block heater because you are smart enough to know that winter happens. If he shows up and all he wants is for you to check his block heater.... There is every chance that he will say "Thanks but no thanks" when you tell him that diag isn't free... This guy is not your customer... all he wants is whatever you are willing to offer for free... Think of this... we can work hard or we can work smart.... If there is a suspect block heater concern, the modified trouble light is still the winner... the "sizzle" and the "warm" are viable tests and do not require the use of a lawn chair... Bottom line.... Winter happens... it happens quite regular. If it surprises you.... Whoa!!!! The block heater.... here is a circuit that just doesn't get any simpler.... If you made a cup of instant coffee this AM, you should be real familiar with the block heater.... Giggle on ladies.... I am extremely surprised something like this has gotten this much mileage. Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted November 29, 2008 Share Posted November 29, 2008 Giggle on ladies.... /forums/images/%%GRAEMLIN_URL%%/whattodo.gif Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted November 29, 2008 Share Posted November 29, 2008 Jim: Remember, in most "normal" parts of the world, we don't experience winter to the level that you do. I'd venture to say that in my area only 20% of block heaters get used on a regular basis. I've seen many old trucks with the cord still wrapped up 'way down in by the battery where KTP put it. IIRC, 6.9/7.3 trucks had the element installed at the factory because the core plug hole was special and a regular freeze plug wouldn't fit it right. We sold block heater cords to those who wanted them, but it was only a handful each winter. A typical winter day here is in the teens at night and 30ishF during the day. We see 0*F a few times per winter, but certainly not every week. Even glow plugs are not critical in my area, a 7.3 PSD can have a few open glow plugs and still start just fine. I have had students from north Alaska that state the truck won't start with ONE open GP. Like I said earlier, amperage is the key for an electrical heater, and an amperage test is by far the quickest and most accurate method of testing an electrical heater. You guys can use the WSM and an ohmmeter all you want, but I'll run circles around you with an amp clamp and accurately test the circuit in 20 seconds or less. With most block heaters going unused, we rarely check them unless the cust says something. Then, it's when he's picking the truck up 'cause he forgot to say something when he dropped it off. In your frozen wasteland I'm sure I would modify my PM list to include a block heater check. I'd be like Aaron- I couldn't handle extreme cold winters. I don't like Florida year round, either, but I will admit to planning about 6 weeks there this season..... /forums/images/%%GRAEMLIN_URL%%/grin.gif Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted November 30, 2008 Share Posted November 30, 2008 Hey, Bruce... I think I came across as sounding a little annoyed in my reply... I apologize to all because, in fact I was annoyed - very annoyed - but not by the thread or anything said... Some other shit spilled over and you guys caught it.... Shit happens and the sun comes up tomorrow... I can't do any more than say I apologize. You are quite right about the demographic thing.... It is all about what we, as individuals, consider as "normal". Every year, along about October, the 15W40 is put to bed and the 0W30 comes out to play... Testing the block heater becomes as important as adding oil or draining the water separator (please, guys... tell us you do this as part of PM). The insidious part... I don't think it get's particularly cold here.... It get's "normal".... Where you live - that ain't normal. Now, for my crude, long term block heater tests... these would be how a cheap assed customer can check his block heater.... While they aren't as quick as the modified trouble light, they are more conclusive than an ohm-meter could ever be on this kind of circuit - word to the wise - the usual place for problems is where the cord enters the molded plug at the bumper. Imagine my initial reaction when Bruce Amacker suggested using an ohm-meter for this test /forums/images/%%GRAEMLIN_URL%%/whattodo.gif AAAWWWWWGGGGGGGG!!!!!! More than ever before.... the only way to test a circuit is to test it with a load.... A new tool is in the planning stage... Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted November 30, 2008 Share Posted November 30, 2008 Not to change the subject too badly, a 6.0 with decent compression, winter fuel (our version of winter fuel) and good batteries will start at colder than -35C (-31F) without the benefit of a recirculating heater... or several of them have in my experience... No, they don't usually sound real pretty for the first few minutes... Some diesel owners seem to agonize over the use of block heaters (a quick visit to the monkey house will show that)... For others, the sight of an extension cord looped around a fence post in the driveway is business as usual. <WARNING!!! ARMCHAIR PHILOSOPHY HAPPENING!!!!> FWIW... this winter is being warmer than any I can recall - perhaps Mother Nature is taking it easy on my Mexicans... At this time, it is 0C and there is pretty much no snow on the ground at all... a little ice in the driveway... One year ago, it was -16 and the snow load in my driveway was threatening to "get away from me"... The only way you could tell I have a car is by the single. black mirror poking out of the snow drift... "So what's your friggin' point, yah dummy old codger???"... Simple.... Mother nature will be the ultimate winner... (Have your truck break down in February, miles away from cell phone service - it can be a long time before anyone comes looking and not everyone is rich in survival technique). With that in mind, we plan for the worst we can expect... Living in the (nearly) north can teach us that... If we don't plan to succeed then we are planning to fail. Back in the 80s, I recall a horrendous cold snap... I had " some" work booked in but it was cold, the ground was frozen - this is the time to be out in the field not in the garage... I had time to "go for a tour". One shop asked why I wasn't as busy as they were... towing trucks in and thawing them out and getting them started..... "All of my customers trucks started....". If there is any chance that an owner may need to use his block heater in your area - what does it take to test his block heater? You do have a multipoint check sheet that is given to the customer, right? One that the service advisor spends a few minutes going over? The one that has a line for "checked block heater operation"? The one that has a nearby line "checked coolant strength"? My gosh... but doesn't it seem like nearly everything in this business is related to everything else in this business? Quote Link to comment Share on other sites More sharing options...
DwayneGorniak Posted November 30, 2008 Share Posted November 30, 2008 Woww, this sure is alot of talk about a whole lot of other stuff that is a affected by a block heater as well as Jim's patience. /forums/images/%%GRAEMLIN_URL%%/poke.gif Hey Jim, I'm thinkin of makin my own modified trouble light, but I'm not sure wether I should use an LED or flourescent light. How bright would each one light if had them modified in series? /forums/images/%%GRAEMLIN_URL%%/smirk.gif Maybe we'll have to indulge into a bottle over this invention hugh? /forums/images/%%GRAEMLIN_URL%%/laugh.gif Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted November 30, 2008 Share Posted November 30, 2008 For the modified trouble light, you will be better off with an incandescent bulb... the higher the wattage, the better.... Remeber that the bulb will be in series with the block heater. We will be testing the circuit at 1/2 it's intended voltage. If the light illuminates with any degree of brightness, you are probably good to go... To properly test the circuit - heavy on the PROPERLY - We will check our source voltage... depending on power authority and time of day, we will see anywhere between (my experience) 108 VAC and 132 VAC.. I am only speaking for physical measurements I have personally made and recall. Without a base volt check, we cannot properly measure voltage drops... (Dang.... there's that word again...). Knowing our base volts, we can perform a voltage drop test on the block heater.... the clincher.... If the volt drop is base volts and the heater doesn't heat... Wow.... If the volt drop is base or close to base volt and the heater does heat... we have made an error in judgement. Our biggest problem is that we seem hell bent on "over-teching" things... Load testing a circuit isn't good enough... We need to use a voltmeter and double check with an ohm-meter and back that up with some other imagined test.... Go to your nonfunctioning load.... If you get a base volt reading - the load is pooched. If you get something other than a base volt reading.... two more steps will tell you if you have a ground side or power side concern... Whoops... getting away from it.... Would you believe that electrical is THE SIMPLEST testing you can ever do.... If the concern can be recreated - it can be fixed easily. This shit isn't any harder than we are going to make it... Oh... yes... incandescent bulbs..... this shit is so easy a cave man can do it... But there are times you need to think like a cave man. Quote Link to comment Share on other sites More sharing options...
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