1980 300td wagon WVO Starting w/STC
Howdy. I'm considering installing a STC conversion to my 1980 300TD wagon, but have a few questions before I do so. When you are running on WVO with the STC 1000 and all the upgrades (Boost Pump, Heated Pathway, Heated filter), how does the engine not need to be flushed out with diesel before shutting down to have proper starting the next day. My understanding of the system is that the oil is heated before it reaches the injector pump, but when you go to start your engine the next morning I don't know if the glow plugs can heat the WVO to a hot enough temperature to start on cold (30s) mornings. Yes I know you can add diesel to your tank to help increase the viscosity on cold days, but what if you weren't expecting it to get cold and you stopped your engine on 100% WVO and then it gets cold the next day. You still have 100% WVO sitting in your injectors and fuel pump to start the engine on a cold day. I don't see how that would be good for your system if you are trying to push cold oil through your injectors. Which is why I think those lines that go parallel on to your injector lines after the pump would be necessary for cold start-ups. However, I haven't seen any mention of these heater lines on this website. Whereas, I have seen them on other Benz's for sale on Ebay, and they say they are crucial b/c they heat the oil up to 220 degrees right before the oil is injected into the cylinder. Is there something I am missing or don't understand about your STC system? I hope so b/c I really like the the STC system's simplicity, design, and price. Thanks for any info or help.
Peace-- Will Pruett
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STC is not for everyone
If you live in a colder climate and are not prepared to plan ahead and mix diesel during the colder months or run on straight diesel when I gets really cold - then the STC 1000 is not for you. We have had an unusual rough winter up here in Washington and I have had to run my STC 93 300D on almost straight diesel since mid December. Injector line heaters will help some but they are not a cure all. If you want to run 100 percent WVO in really cold weather you need to have a dual (DTC) tank system so you can start up and shut down on straight diesel... and from our experience that is not a fun proposition if you have a wagon... My own experience with a dual tank system in my daughters wagons is what prompted me to develop the STC system!
Thanks for the info Kent. I
Thanks for the info Kent. I live in Tennessee where it only gets below freezing a few weeks out of the year... I was thinking about using the STC 1000 with the upgrades and having an extra 2 or 3 gallon diesel tank behind the spare tire to start and stop on really cold days. I probably won't get my conversion running until spring anyways b/c I have some other work to do on the wagon before I convert. I was just curious if it was feasible to run on the STC in below freezing weather. Maybe a small diesel tank will be the way to go for stop and start up on really cold days. That way I won't have a big veggie tank in the back that I have to heat causing the cab to heat up also and probably spill veg in the back. Thanks and keep on trucking.
Peace-- Will
STC cold weather operation
With a healthy engine with good compression you can run a STC in the 25 to 32 degree range for short trips. The trick is getting it started without a lot of cranking and start up smoke. If you have a block heater you can plug in at night then this problem is solved. Kaia has been stuck a few times in her wagon with full veggie during a cold overnight. No problem. Just heat up a kettle of hot boiling water and go out and pour it over the injectors and injector lines. :-)
After one year of running her wagon with a small 3 gallon diesel tank in the back of her wagon, we were so happy to get rid of it that we celebrated by throwing it out in the field! The constant smelll, spills, refueling, running out of fuel, hassle of it getting in the way of cargo. etc. was just too much to handle. She would much rather deal with mixing diesel any day....
One more thing. If you plan on running WVO, Monark injector nozzles are a must have for efficient STC and DTC operations. Smoother starts, more power, less smoke and much better fuel economy.
STC with WVO on a 300TDT Wagon
Hi Will-
Kent has answered with some sound advice (per his usual).
I live in CA and have converted my wagon to a STC a year ago. We see freezing only a few times, but can get to low 40's regularly in winter.
I believe that aside from a conversion kit, the entire system has to be looked at. Kent refers to all of these issues on the website and sells all of these parts.
I recommend, based on my own experience, that you should upgrade the electrical system, meaning a 'super battery' (an OPTIMA) as recommended by Kent.
A Bosch Super Glow Relay (with extended glow plug heating) New Bosch Super Glo Pugs, and, as Kent mentioned, the Monark injectors (a must when running oil). I also installed a new 55amp alternator.
I would also suggest a valve adjustment and Diesel Purge before you switch to oil.
The better condition all systems are on your wagon, the better and smoooother your oil experience will be.
During this time of year I run 15-20% Diesel with my oil and the car starts on the first crank-even on the coldest mornings...
It has to be one big package deal working together - not just a conversion kit!
OK, enough said, and best of luck with your conversion!
Diesel Don