Thermostart

ghostlymoron

ghostlymoron

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Not wishing to highjack the Watermota discussion, I thought I'd better start a new thread.
A pal of mine has just purchased a Thermostart unit for his BMC Capitan which is difficult to start. He told me that he intends connecting it to his glow plug circuit so that it runs at the same time. Having looked up a bit of info on these, I don't think this will work and may even be dangerous. Am I right in thinking that the Thermostart need to run when the engine is cranking? If so, it seems that the Thermostart needs to be connected through the start button.
Any thoughts?
 
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Thermostart will do little good on an indirect injection motor, the combustion chamber throat will absorb the heat which is why they have glowplugs these days instead.

You need to look elsewhere to solve the starting issues. Swapping the existing glowplugs may work wonders.

I can remember the old Perks 4236 with thermostart fitted and the only way to get them going on a cold morning was with a can of liquid compression.


Just reread your post and the answer to your question is that the thermostart was energised prior to cranking for a minute or so, usually by depressing the ignition key in the lock to warm the plug, then cranking supplied more fuel.
 
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Renewing glow plugs.

ghostlymoron said:
Not wishing to highjack the Watermota discussion, I thought I'd better start a new thread.
A pal of mine has just purchased a Thermostart unit for his BMC Capitan which is difficult to start. He told me that he intends connecting it to his glow plug circuit so that it runs at the same time. Having looked up a bit of info on these, I don't think this will work and may even be dangerous. Am I right in think that the Thermostart need to run when the engine is cranking? If so, it seems that the Thermostart needs to be connected through the start button.
Any thoughts?
Click to expand...

Have a look at this link on Thermostarts.

http://www.hoyetractor.com/thermostart.htm

Other point is that it is important to clean out all the carbon in the glow plug holes as shown below.

http://www.youtube.com/watch?v=K4rTfRx82e8
 
Have a look at the recent thread on thornycroft 90 BMC 1.5. Glow plugs
Captain I think actually covered more than one engine over he years.
 
I found the biggest improvement in starting a BMC 1.5 was changing from a leisure battery to a proper starting battery, whizzed away every time. The old manual did suggest 30 secs of preheat before trying to start. The other big help is giving it a good long run under power, and by long I mean more than 12 hours
 
I think it is well known that the Volvo 2003 and probably the 1 & 2 can end up with severe starting problems but then seem to run perfectly once started. I solved my bad starting VP2003 with a Thermostarter. I made up an extension piece between the air filter and the engine block with the Thermostarter fitted to that. On an engine that in the past would run the battery flat rather than start, it now starts without fail. I have an extra start button that I hold for about 20 seconds for the first start of the day and then press the stater button. Because it is pre heating the inducted air I can't imagine it matters whether injection is indirect or not. The easiest way to test whether a Thermostarter will sort out your particular engine is to remove the air filter and aim a lighted blowlamp into the air intake as you press the starter. Bear in mind that lighted blowlamps in boats are very dangerous so do it with two people, one in charge of the blowlamp and the other at the starter button & throttle!
 
Lazy Kipper said:
What do you do with an engine that doesn't have any glow plugs anyway :(
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you might like this. Our engine has no glow plugs (1940's vintage). There is a 'rich' position on the pump and then there is the 'let's go for broke' cartridges in the top of the engine. 3/4 calibre cartridges that you fill with oil. It works!, but in central London, you would be arrested.
 
Lazy Kipper said:
What do you do with an engine that doesn't have any glow plugs anyway :(
Click to expand...

Bit unconventional this and still in the 'testing stage', but although she starts fine warmer days, my md5 was a pig to start on really cold days. She'd always start eventually, but needed winding over for an absolute age to start. At thirty years old the air filter was getting a bit perforated with rust, so whilst undertaking a refurb (couldn't find a replacement) I cunningly built-in the heating element from a 12v windscreen de-icer I had lying around, in the hope of warming the in-going air a tad. (burning a roll of newspaper under the air intake like we did with trucks in the old days didn't seem too safe on the boat)

The element only draws a couple of amps, but gets too hot to touch. Simple lead to cigar-lighter plug to 12v socket on boat.

So far, it looks like rather than the anything up to 5 minutes of intermittent cranking to start on frosty mornings, if I give it two-three minutes plugged in, pull the 'cold start' (extra fuel) knob, she'll fire up within 6-7 rotations. No doubt some-one on here will tell me the error of this mod, but I'm chuffed so far.
 
stuhaynes said:
you might like this. Our engine has no glow plugs (1940's vintage). There is a 'rich' position on the pump and then there is the 'let's go for broke' cartridges in the top of the engine. 3/4 calibre cartridges that you fill with oil. It works!, but in central London, you would be arrested.
Click to expand...

Is that the old Field Marshall tractor engine like this?

http://www.youtube.com/watch?v=01Sr8S9uQMc
 
I had a Perkins 4-108 with a Thermostart in a Datsun truck (go figure..) The tecnique was to give a few turns to get the fuel pressure up,then hit the pre-heat button to warm up the thermostart coil. When it got to temp, the little ball allowed the fuel out and it atomized. If you judged it right, the starter then kicked it off.
DW
 
Davegriff said:
Bit unconventional this and still in the 'testing stage', but although she starts fine warmer days, my md5 was a pig to start on really cold days. She'd always start eventually, but needed winding over for an absolute age to start. At thirty years old the air filter was getting a bit perforated with rust, so whilst undertaking a refurb (couldn't find a replacement) I cunningly built-in the heating element from a 12v windscreen de-icer I had lying around, in the hope of warming the in-going air a tad. (burning a roll of newspaper under the air intake like we did with trucks in the old days didn't seem too safe on the boat)

The element only draws a couple of amps, but gets too hot to touch. Simple lead to cigar-lighter plug to 12v socket on boat.

So far, it looks like rather than the anything up to 5 minutes of intermittent cranking to start on frosty mornings, if I give it two-three minutes plugged in, pull the 'cold start' (extra fuel) knob, she'll fire up within 6-7 rotations. No doubt some-one on here will tell me the error of this mod, but I'm chuffed so far.
Click to expand...


That's got me thinking - I'm putting in an Eber at the moment with the heater duct going past the air filter, what about a T junction with a shut off that blew hot air into the filter (I say filter but its just some chicken wire) ??? We'd be running the Eber on any day that was cold enough to make starting the old girl a bit iffy. Having said that on 2C day she took 15 or 20 seconds to start and I thought that was a long time - maybe not so long then???
 
Lazy Kipper said:
Having said that on 2C day she took 15 or 20 seconds to start and I thought that was a long time - maybe not so long then???
Click to expand...

Well, I'll lift her out sometime Jan/Feb for anti-foul etc, so will probably do a much needed service around injector, pump etc at same time. Right now, I've had to roll the car down-hill last 3 mornings so looking like heaters in there want doing first! VWs used be so reliable......
 
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