I've used these in many cars for 50 years with very good results, but in more recent times I've had these fail after 1-5 years of occasional winter use. Kats were first seen as seem iffy, but also the Tempro have had failures. Also OEM that I think some of Canadian manufacture. I had wondered if modern coolant was somehow a problem, but after pulling out the bad units, there were no visual signs. The circuit would opened up internally. These are typically 400 watts. Any ideas out there?
Block heater failures
- Thread starter Lapham3
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They don't make 'em like they used to?
Last block heater that I used was on my Mercedes 240D. Worked perfectly for the life of the car. Genuine MB part.
So, these failed parts are aftermarket? Or OEM?
Last block heater that I used was on my Mercedes 240D. Worked perfectly for the life of the car. Genuine MB part.
So, these failed parts are aftermarket? Or OEM?
These are ones that replace a freeze-out plug? I had one in my 1980 VW Rabbit diesel. Worked fine if I remembered to plug it in.
A lot of block heaters are now dry-type where they warm the block and the block warms the coolant and they don't touch the coolant directly. They also are built for energy savings so they have lowered the wattage and built in thermostats. My old block heater in my Pontiac 6,000 was 1500 watt coolant type without thermostat (just high temp overload cut out) and the one in my modern day Caravan is 400 watts dry type with thermostat.
The one in my Pontiac 6000 would keep the coolant not far from operating temperature whereas the one in the Caravan keeps it at best 90-100F (about 1/2 the operating temperature)
The way around this is to install a coolant heater on the lower radiator hose. Katz makes an excellent one that I have used on hard to retrofit vehicles and it comes in various hose sizes. Works great.
The one in my Pontiac 6000 would keep the coolant not far from operating temperature whereas the one in the Caravan keeps it at best 90-100F (about 1/2 the operating temperature)
The way around this is to install a coolant heater on the lower radiator hose. Katz makes an excellent one that I have used on hard to retrofit vehicles and it comes in various hose sizes. Works great.
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Nevermind
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There is a self diagnostic of the block temp sensor required by US emissions, and they decided to lower the wattage of the block heater so the engine never got all that hot. A high wattage heater can result in a code on some cars.
Rod
Rod
I've had and used about all of the heaters excepting the dip stick type which seemed silly. The 'freeze plug' type is what I'm referencing and aren't lasting. I'm guessing a probable quality control issue, but strange across different manufacturers. I have an old 1200 watt circulating tank heater on a 60's vintage Nailhead engined Buick and lower radiator type on a couple cars as well. They've been fine for decades. My wife will drive a Toyota with the weak cartridge heater. I can't imagine that does very much in extreme cold. Historically, many dealers around here routinely ordered cars with the freeze plug style as it's an effective and very cheap option. So far the OEM one in my 2006 Chev with the 3900 is fine.
I've had mixed luck recently with these. When I visit my folks in MN, I have to park my car outside so I want something to help the engine out. I've had good luck in the past ordering the OEM block heater, sometimes through a search involving Canada. I think there must be a law that all Canadian cars have some sort of engine heater.
If it's the "cut the hose and install this chunky heater", I've given up on those. They are for tractors in my opinion. It's two more hose clamps and a housing that are likely to leak and I've had these last all of two cycles.
Many of the new heaters have a thermostat included on them and it's not what you think. That is there to prevent the block heater from working until the ambient temperature is very low, not the engine temperature. It has to due with diagnostics on coolant temperature sensors. The ECM uses multiple sensor readings (usually at key-on) to determine if one of them is out to lunch. Having an active block heater would terribly skew your coolant temperature sensor (but not your intake air temperature sensor) and cause the diagnostic to fail. The thermostat on the block heater makes sure that the outside temp is low enough that diagnostics aren't running anyway.
On a couple of my newer cars, the block heater is buried deep in the engine somewhere and I didn't want to take the whole front of the car apart just to get in there.
I've resorted to the flat-panel style oil pan heaters that you glue to the bottom of the oil pan. You can get some pretty serious power outputs and it's the oil I'm trying to get circulating anyway. They are way easier to install and get the oil warm to the touch even in subzero weather. None that I have seen have a thermostat of any kind, I presume they use the resistance increase of the heater grid to reduce power. I've only had one fail and that was because some road debris bounced up and slashed it (thanks Michigan "roads"), it might have saved the oil pan in that case.
If it's the "cut the hose and install this chunky heater", I've given up on those. They are for tractors in my opinion. It's two more hose clamps and a housing that are likely to leak and I've had these last all of two cycles.
Many of the new heaters have a thermostat included on them and it's not what you think. That is there to prevent the block heater from working until the ambient temperature is very low, not the engine temperature. It has to due with diagnostics on coolant temperature sensors. The ECM uses multiple sensor readings (usually at key-on) to determine if one of them is out to lunch. Having an active block heater would terribly skew your coolant temperature sensor (but not your intake air temperature sensor) and cause the diagnostic to fail. The thermostat on the block heater makes sure that the outside temp is low enough that diagnostics aren't running anyway.
On a couple of my newer cars, the block heater is buried deep in the engine somewhere and I didn't want to take the whole front of the car apart just to get in there.
I've resorted to the flat-panel style oil pan heaters that you glue to the bottom of the oil pan. You can get some pretty serious power outputs and it's the oil I'm trying to get circulating anyway. They are way easier to install and get the oil warm to the touch even in subzero weather. None that I have seen have a thermostat of any kind, I presume they use the resistance increase of the heater grid to reduce power. I've only had one fail and that was because some road debris bounced up and slashed it (thanks Michigan "roads"), it might have saved the oil pan in that case.
My coolant temperature is 100F in 32F weather and 90F at anything below 25F and it's the Dry-Type in the PentaStar. I use it from the late fall all the way through until the spring. These are the temperatures as displayed by my ScanGauge.
Originally Posted by Astro14
They don't make 'em like they used to?
Last block heater that I used was on my Mercedes 240D. Worked perfectly for the life of the car. Genuine MB part.
So, these failed parts are aftermarket? Or OEM?
I remember that. Even living in lower elevation in California, my dad got one installed in his leased 300D Turbo. I remember there was a coupon - might have been in the owners manual or a separate one tucked in the owners manual jacket.
I guess he was thinking of taking it up to Tahoe in the winter, but I'm not sure where he could have plugged it in. I don't believe it was ever used.
They don't make 'em like they used to?
Last block heater that I used was on my Mercedes 240D. Worked perfectly for the life of the car. Genuine MB part.
So, these failed parts are aftermarket? Or OEM?
I remember that. Even living in lower elevation in California, my dad got one installed in his leased 300D Turbo. I remember there was a coupon - might have been in the owners manual or a separate one tucked in the owners manual jacket.
I guess he was thinking of taking it up to Tahoe in the winter, but I'm not sure where he could have plugged it in. I don't believe it was ever used.
A lot of older Mercedes diesels came with the heater preinstalled, you just had to pop the cap off and put a cord on it. That's the way my ‘82 300D was, it never had a heater cord on it until I put one on it.
Originally Posted by bullwinkle
A lot of older Mercedes diesels came with the heater preinstalled, you just had to pop the cap off and put a cord on it. That's the way my ‘82 300D was, it never had a heater cord on it until I put one on it.
Mine sure wasn't pre-installed...You had to remove a threaded freeze plug. It was about 2' across, with fine threads and a copper sealing ring.
And it took a 4 foot cheater pipe, made using a floor jack handle, on a 1/2 drive breaker bar, with a 17mm hex drive that I had crafted by cutting through a 17mm allen wrench. No amount of leverage on that allen wrench would budge the freeze plug.
I remember the car itself moving upward as I stood underneath the cheater pipe, lifting with my legs while I put my shoulder into the pipe, before it broke free.
I estimated the torque at about 800-1000 lbft...
Anyway...simple install once that plug was out. Reliable unit.
A lot of older Mercedes diesels came with the heater preinstalled, you just had to pop the cap off and put a cord on it. That's the way my ‘82 300D was, it never had a heater cord on it until I put one on it.
Mine sure wasn't pre-installed...You had to remove a threaded freeze plug. It was about 2' across, with fine threads and a copper sealing ring.
And it took a 4 foot cheater pipe, made using a floor jack handle, on a 1/2 drive breaker bar, with a 17mm hex drive that I had crafted by cutting through a 17mm allen wrench. No amount of leverage on that allen wrench would budge the freeze plug.
I remember the car itself moving upward as I stood underneath the cheater pipe, lifting with my legs while I put my shoulder into the pipe, before it broke free.
I estimated the torque at about 800-1000 lbft...
Anyway...simple install once that plug was out. Reliable unit.
Originally Posted by Lapham3
Historically, many dealers around here routinely ordered cars with the freeze plug style as it's an effective and very cheap option. So far the OEM one in my 2006 Chev with the 3900 is fine.
Actually, the dealers don't even have to order them in a lot of cases - the manufacturer automatically equips vehicles going to certain destinations with them regardless. Not all, but some. Ford has been this way with F150's for many, many years. (Though interestingly in 2019 they became optional).
Historically, many dealers around here routinely ordered cars with the freeze plug style as it's an effective and very cheap option. So far the OEM one in my 2006 Chev with the 3900 is fine.
Actually, the dealers don't even have to order them in a lot of cases - the manufacturer automatically equips vehicles going to certain destinations with them regardless. Not all, but some. Ford has been this way with F150's for many, many years. (Though interestingly in 2019 they became optional).
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Originally Posted by Lolvoguy
Originally Posted by StevieC
The one in my Pontiac 6000 would keep the coolant not far from operating temperature
I find this very hard to believe.
Unless you were plugging in during times of ambient temps over 60F
I believe it. I have a 400w in my Kubota with the D600 that will overheat the cooling system in about an hour. Granted things are much smaller, but this is an hour's worth of use too.
Originally Posted by StevieC
The one in my Pontiac 6000 would keep the coolant not far from operating temperature
I find this very hard to believe.
Unless you were plugging in during times of ambient temps over 60F
I believe it. I have a 400w in my Kubota with the D600 that will overheat the cooling system in about an hour. Granted things are much smaller, but this is an hour's worth of use too.
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This reminds me that I bought a magnetic pan heater some time ago...it actually ended up being a very useful tool for one of my daughter's school science projects.
I have no idea where that thing is now...
I have no idea where that thing is now...
Originally Posted by Lolvoguy
Originally Posted by StevieC
The one in my Pontiac 6000 would keep the coolant not far from operating temperature
I find this very hard to believe.
Unless you were plugging in during times of ambient temps over 60F
I know what I saw. At start up the gauge would move to 1/4 and then within a few minutes move to the 1/2 way mark indicating operating temperature. It had the 4 cylinder in it.
Originally Posted by StevieC
The one in my Pontiac 6000 would keep the coolant not far from operating temperature
I find this very hard to believe.
Unless you were plugging in during times of ambient temps over 60F
I know what I saw. At start up the gauge would move to 1/4 and then within a few minutes move to the 1/2 way mark indicating operating temperature. It had the 4 cylinder in it.
Originally Posted by Virtus_Probi
This reminds me that I bought a magnetic pan heater some time ago...it actually ended up being a very useful tool for one of my daughter's school science projects.
I have no idea where that thing is now...
My last one went to the scrap yard with the Santa Fe. I was going to put a Wolverine one on the Journey but never got around to it. I still have it and I have been debating putting it on the van or selling it because the block heater seems to be enough for my liking.
This reminds me that I bought a magnetic pan heater some time ago...it actually ended up being a very useful tool for one of my daughter's school science projects.
I have no idea where that thing is now...
My last one went to the scrap yard with the Santa Fe. I was going to put a Wolverine one on the Journey but never got around to it. I still have it and I have been debating putting it on the van or selling it because the block heater seems to be enough for my liking.
Originally Posted by bullwinkle
A lot of older Mercedes diesels came with the heater preinstalled, you just had to pop the cap off and put a cord on it. That's the way my ‘82 300D was, it never had a heater cord on it until I put one on it.
I don't remember that being the case with the '84 one that my dad drove. Couldn't find it here, but it could have been in a page that wasn't scanned or perhaps a separate page. I do remember reading the list of approved motor oil brands. I'm not sure exactly how it worked since many were European brands like Duckham, and the other brands were likely to be a different formula in Europe (even in different European countries) vs the US.
http://assets.mbusa.com/vcm/CAC_RAPMD/images/84 300D 300CD OM.pdf
I see they recommended 10W-40 or 10W-50 as a year round grade. Also 20W-20 and 20W-30 are on their chart. And strangely enough I see 5W-20.
A lot of older Mercedes diesels came with the heater preinstalled, you just had to pop the cap off and put a cord on it. That's the way my ‘82 300D was, it never had a heater cord on it until I put one on it.
I don't remember that being the case with the '84 one that my dad drove. Couldn't find it here, but it could have been in a page that wasn't scanned or perhaps a separate page. I do remember reading the list of approved motor oil brands. I'm not sure exactly how it worked since many were European brands like Duckham, and the other brands were likely to be a different formula in Europe (even in different European countries) vs the US.
http://assets.mbusa.com/vcm/CAC_RAPMD/images/84 300D 300CD OM.pdf
I see they recommended 10W-40 or 10W-50 as a year round grade. Also 20W-20 and 20W-30 are on their chart. And strangely enough I see 5W-20.
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