Glow pug circuit

[toolsplus]

Sometimes when it's cold my 120 cuts out just after starting. Now I'm waiting a few seconds before starting even tho' the glow plug light is out. Does the glow plug system keep on warming while the glow plug light is out?
How long does the glow plug system heat for,is it about 30 seconds?
It doesn't cut out if I wait about 5 seconds before starting.
Cheers

 

[karl2000]

How cold is cold?

I think it keeps going for a while after the light is out, but I dont know how long for. Do you have a heater on your fuel filter?

(SCV is the newer long version right? As you know, usual suspect for cutting out engines!)

 

[toolsplus]

Don't know about the SCV Karl or heater on the fuel filter.
It's not that cold,about 10 deg.C starts...

 

[karl2000]

Tbh for 10 degrees i dont even think it would need glowplugs. Im sure ive just started right through from cold once or twice at that temp when mind is on other things!

 

[toolsplus]

When I waited 10 secs before turning over this morning it settles down to an idle quicker and doesn't vibrate so much.
How do I know if I have the newer SCV ?
Do some models have a fuel filter heater?
Cheers

 

[karl2000]

Theres loads of threads on here about the SCV (suction control valve) - its in the back of the high pressure diesel pump. The old ones were short and are problematic; the redesigned ones are longer and more reliable. If youve got the old type you should probably consider replacing it amyway before it leaves you stranded - loads of people here have done that.

I think the fuel filter heater is optional and probably only fitted with the cold weather pack (have you got two batteries?). I'll take a pic tomorrow when its light!

 

[Shayne]

Suspecting its a fuel problem and only occasional I would fit a non return valve in the line before investing much .

 

[toolsplus]

2 batteries Karl.
Will my VIN No. tell me if I have the newer SCV?
Can you suggest a decent thread so I can identify which SCV I have?
Cheers

 

[toolsplus]

Found the thread Karl,mine's the short SCV. While everything's working I'll leave it alone.
I started the 120 all day without waiting at all. It started no problem and the tickover settled quickly.
It's now my new starting technique!
Key in,turn hold and start...

 

[karl2000]

Put it on your list to upgrade though, otherwise it will let you down when you least expect it!

 

[toolsplus]

It looks an easy accessible DIY job,is it?
How much is an OEM SCV from Mr.T?
After how many years or miles are they packing in?
Cheers

 

[karl2000]

Its straightforward but fiddly and youll swear when you drop the screws.

Fourby4diesel has a video showing you how to do it

Dont know how much they are from T - i bought mine from roughtrax a few years back

I think they can fail anytime - all these trucks are older now!

 

[Tractionman]

There was lots of swearing with mine - getting the wiring coupling unclipped was a bugger for me, which should have been so simple. Usual Toyota press tab in and pull both halves apart, but I couldn't seem to get tab pressed in far enough to release while I was hanging down over the wing
Karl must have had a right laugh when I told him I couldn't get it apart after having several goes over as many days. He persuaded me not to use a BFH !
The rear bolt on the scv, you are pretty much going by feel with the Allen key, as your hand will be blocking visual and there is a pump screw close to it (same type), I undid that one, and wondered why the scv wouldnt slide out (after releasing the front one of course). More swearing !
Be scrupulously clean - clean everything above and around the old scv before starting, you dont want any sh*t in the pump removing or replacing the scv.
Even with the small problems I encountered, an easy job.

 

[toolsplus]

Thanks TM,sounds like a good exercise in patience

 

[Tractionman]

If you drop any screws they inevitably end up on the sump guard, (oem or aftermarket) where you cant see or get at them. A telescopic wand type magnet is invaluable here to swipe the area from either above or below, bearing in mind it has a natural desire to grab a steel sump guard too (or anything else attracted to) just keep pulling it to slide across the surface and (hopefully) bring the screw with it. A very useful bit of kit for any awkward items to locate with a very strong magnet for size.

 

[toolsplus]

5 degC this morning and put the key in then turned it immediately,started and ticked over perfectly.
You can't beat trial and error