Converting old thermostart to electric

   / Converting old thermostart to electric #1  

Strahwberry

New member
Joined
Sep 23, 2021
Messages
10
Tractor
YM155D
Hello! I was wondering if anyone had, and if they thought it was worth it to convert the thermostart to an all electric heater. I've started looking at something like:
https://www.amazon.com/Standard-DIH4-Diesel-Intake-Heater/dp/B01BTTZ8GG
or
https://www.amazon.com/Standard-Mot...dp/B0052XIOCG/ref=psdc_15719731_t2_B01BTTZ8GG

I have emails out to sellers to check size dimensions to see if it would even fit.

I'm keeping my tractor in my shop this winter and it'll be heated to 40 degrees. Warmer than outside, but, still cold enough to need pre-heat.

Thanks!
Jon
 
   / Converting old thermostart to electric #2  
Intake air heaters work - I had one in my Dodge diesel pickup. Is it possible to replace the Thermostart with a standard glow plug? Another option might be a block heater but that would involve plugging it into power to warm the engine before starting. Even so, a warm engine is easier to start than a cold one. I did that when the glow plugs failed in a Chevrolet diesel.
 
   / Converting old thermostart to electric #3  
I wouldn't add that complexity. You would need a high-current relay and some new wiring plus there isn't space in the manifold for anything larger than the original Thermostart element. Are you sure yours is working properly?

Thermostart, and topping up its reservoir for the old style, should easily start a little YM155. Especially inside a 40 degree shop.

A simpler solution if that Yanmar is hard starting indoors, is to warm the head with a heat gun or hair dryer. But you should never have to do this if the engine isn't worn out.

A block heater would be a better choice.
 
   / Converting old thermostart to electric #4  
I have the first one on a Deutz tractor engine. It works. However, I don't think that it buys you anything over the standard Yanmar thermostart. Both of them function by preheating the intake manifold that then warms the air going into the engine, that in turn promotes rapid ignition; I suspect that the thermostart actually has the hidden benefit of some volatilized fuel to "prime" the initial crank, but I have no evidence for that.

If it were me, I would not replace the thermostart with something else. Block heaters, and oil heaters are fine for reducing the load on the starter, but for diesels what really is important for ignition is warm air. (In my opinion)

I confess that I am with @California that at 40F, your thermostart should be all you need. If it were me, and starting at 40F was an issue, I would double check that the thermostart itself is working, and the. I would look for other possibilities like dirty air filters, fuel filters, injection systems needing some injector cleaner (sea foam, liquid moly, etc.)

I think that these Yanmar engines are exceptional, and if they aren't just working, they probably just need some minor TLC. Personally, I have had a single fueling of some poor quality diesel cause a variety of problems.

All the best,

Peter
 
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   / Converting old thermostart to electric #5  
Hello! I was wondering if anyone had, and if they thought it was worth it to convert the thermostart to an all electric heater. I've started looking at something like:
Amazon.com
or
Amazon.com

I have emails out to sellers to check size dimensions to see if it would even fit.

I'm keeping my tractor in my shop this winter and it'll be heated to 40 degrees. Warmer than outside, but, still cold enough to need pre-heat.

Thanks!
Jon
Jon,
Yanmar and Deere did do an all electric air heater for the newer models we see today, but not like the amazon products you have shown. See the link. It's in many Yanmar and Deere machines.


This tech is not new, Mitsubishi has used it over the years. There is a control box with one or two relays. Just depends on the IC used. 1 relay control has relay to activate and IC ~3min timer to shut off. The 2 relay control has relay to activate IC to a temp probe and then triggers 2nd relay to turn the system off. In the 2 relay setup, people bypassed the temp probe cut-off and run the air heater full time in those minus temp regions.



We've covered this a few times in the past, about this time of year too. It tends to trend enough.
 
   / Converting old thermostart to electric #6  
Does the posters engine have a decompression lever.?
Is it being used.?
 
   / Converting old thermostart to electric #8  
   / Converting old thermostart to electric #9  
The draw on that preheat unit that @LouNY suggested is 200A, jumperable down to 100A, and the DIH4 preheat is 80A or so. That needs a fairly large battery to handle the draw... Does a YM155D have that big a battery?

All the best,

Peter
 
   / Converting old thermostart to electric #10  
The draw on that preheat unit that @LouNY suggested is 200A, jumperable down to 100A, and the DIH4 preheat is 80A or so. That needs a fairly large battery to handle the draw... Does a YM155D have that big a battery?

All the best,

Peter
OUCH.

It's not the battery size I would be worried about, these old tractors use the Datsun (Nissan) 35A 1970s era alternators. Some of the aftermarkets are 45A and a GM type with small modifications is a 60A type.

I would stick to a Thermo-start. For the 2 or 3 tablespoons of diesel, nothing is missed.
 
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   / Converting old thermostart to electric #12  
FWIW: Here is a Thermostart diagnosis, disassembly, and replacement. (On a slightly larger machine...)

All the best, Peter
 
   / Converting old thermostart to electric #13  
FWIW: Here is a Thermostart diagnosis, disassembly, and replacement. (On a slightly larger machine...)

All the best, Peter
FWIW the Thermostart portion of the video starts at the 4 minute point.

Slide-on vs screw electric connector is the only difference between versions and most will take either. They are cheap to replace. I see several under $15 on Ebay.
 
   / Converting old thermostart to electric #14  
FWIW the Thermostart portion of the video starts at the 4 minute point.

Slide-on vs screw electric connector is the only difference between versions and most will take either. They are cheap to replace. I see several under $15 on Ebay.
About $9 on Amazon if ordering the Ford 1000 Series tractor types. It's the same product. We pay a tad bit more for the Yanmar name, even in the aftermarket circles. I've already replaced mine last year with the Ford identical version.
 
   / Converting old thermostart to electric #15  
About $9 on Amazon if ordering the Ford 1000 Series tractor types. It's the same product. We pay a tad bit more for the Yanmar name, even in the aftermarket circles. I've already replaced mine last year with the Ford identical version.
Great! Amazon is the best source then.

Before posting I searched Amazon on 'Thermostart' and nothing at all was found. So I went to Ebay.

It was/is also used on the Perkins diesels in MF, and many other tractors and industrial engines. The device is a Perkins patent.

What does Ford call it?

Photo after I bought a new one at the local ThermoKing (reefer on semitrailer) dealer.
dscn5123thermostart-perkinsbox-jpg.68476
 
   / Converting old thermostart to electric #16  
Great! Amazon is the best source then.

Before posting I searched Amazon on 'Thermostart' and nothing at all was found. So I went to Ebay.

It was/is also used on the Perkins diesels in MF, and many other tractors and industrial engines. The device is a Perkins patent.

What does Ford call it?

Photo after I bought a new one at the local ThermoKing (reefer on semitrailer) dealer.
dscn5123thermostart-perkinsbox-jpg.68476
Ford calls it a Thermo-start air-intake heater or manifold heater.

I bought mine thru AI products (aka John Deere owned aftermarket co.) here:

It's listed on Amazon for $15 thru others now.

 
   / Converting old thermostart to electric #18  
The hard parts to find are the tubing lines and little reservoirs.
 
   / Converting old thermostart to electric #19  
Thermostart works fine if it works properly. My old big tractor was a beast to start. So I got two freeze plug heaters, a lower radiator hose heater, covered the hood with a blanket. Plug it up and it was hot in 30 minutes. I like cranking a warm engine, easier on the engine. Most wear happens on cold starts. I had thermostart too, but it was easy when warm, busted right off.
 

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