13B-T glow plugs or not?

[Rouke]

Hi, I just joined the mud h8ers. I recently bought a BJ74 with a 13B-T engine. Lately it was getting harder to start, unrelated to the weather, until I couldn't get it to start at all. It fires, runs for about a second and then stalls. So I contacted the AA and it had to be towed to the garage for 'repairs'. Upon contacting the garage, but before the TLC got there, I was told the glow plugs were probably gone, but I didn't think it had any glow plugs that could go. So I ended up googling to see if the 13B-T engine had glow plugs or not. I haven't been able to find a confirmation that it does. Some people showed pictures of different engines showing glow plugs and connections, but I'm still unconvinced. We'll wait and see if they can be found when in the garage.

 

[Nas90tdi]

If it fires and runs then dies, it's unlikely glow plug related either way. Most likely culprit is air getting into the lines somewhere when it's shut down.
Can't answer the actual question as I have never had a 13BT, but don't let a shop talk you into glow plugs in that scenario without some pretty compelling evidence. If a diesel will fire, it will run at whatever temp you are discussing usually.

And, a direct injection will usually crank with no plugs well past 0C.

 

[cruiserdan]

The 13BT does NOT have glow plugs. It is a direct-injection engine and has an air pre-heater screen in the intake manifold much like a Cummins 6BT. In Toyota lingo it is a "glow screen".

Pre-heating in these engines does not activate until ambient temps are fairly low. As a result they do not start easily between about 40 degrees F and 25 degrees F.

I find it necessary to give about 1/3 to 1/2 throttle on a cold start in this temp range and I use the hand throttle to increase the revs while the engine warms up a bit. It does absolutely no good to repeatedly "pump" the throttle as there is no carburetor or electrical ignition.

 

[Nas90tdi]

Oh yeah, I did actually know that. Had slipped my mind. Old brain that reads to much. It leaks more than it used to.

 

[FJBen]

Yep, glow screen only. I found mine doesn’t kick on until below freezing ~25ish F or less. I haven't had much issues starting down to 2ish F this year after sitting for a few days.

Sounds like a fuel issue to me. Has the fuel filter been changed in awhile?
These old engines don't need much, air, fuel and compression. Unless you have some very bad compression, I'm leaning more towards fuel. How did it run after starting when it was getting harder and harder to start?

 

[cruiserdan]

One thing just occurred to me. There may be a low oil pressure shutoff.

 

[Behemoth60]

My money is on that other goofy thing on the 13B-T... the vacuum actuated shut-off valve.

Try pulling off the vacuum lines going to that flapper valve (it's just above the glow screen on the intake). That will allow the shut down flapper valve to stay open (and prevent you from shutting off the engine with the key) but it will help your diagnose whether you have a leaky or defunct vacuum shut down valve.

Theory of operation... When it is time to shut off the 13B-T, A vacuum solenoid (located under the intake) opens, allowing application of vacuum to actuate the shut down air intake flapper valve, closing off air to the engine, and shutting off the engine. The vacuum solenoid has at least 3 conditions when it will try to shut off the engine - turn ignition key off, low oil pressure, and low manifold intake pressure (presumably because your intake just went underwater... the engine will shut down to prevent hydrolocking, which is good - but if you have dirty air filter, this will also trigger as you are approaching max RPM when trying to merge onto the freeway, which is bad. )

If the solenoid has failed 'open' or some other electrical failure is keeping it open, it will shut down your engine as soon as enough vacuum is built up to trigger the shut down valve, after a few seconds (which matches your problem description)
If the solenoid has failed closed, or you have a vacuum leak in your system, it will be impossible to shut off the engine with the key (this is clearly not your problem, but I share for general knowledge )

 

[cruiserpilot]

Hi, I just joined the mud h8ers. I recently bought a BJ74 with a 13B-T engine. Lately it was getting harder to start, unrelated to the weather, until I couldn't get it to start at all. It fires, runs for about a second and then stalls. So I contacted the AA and it had to be towed to the garage for 'repairs'. Upon contacting the garage, but before the TLC got there, I was told the glow plugs were probably gone, but I didn't think it had any glow plugs that could go. So I ended up googling to see if the 13B-T engine had glow plugs or not. I haven't been able to find a confirmation that it does. Some people showed pictures of different engines showing glow plugs and connections, but I'm still unconvinced. We'll wait and see if they can be found when in the garage.

I would look at your fuel system, fuel filter. Was it ever sitting for a long time? I’m thinking contamination,
sediment build up

 

[jblueridge]

I agree with Behemoth.
Vacuum shut off switch failure produces that same set of symptoms.

 

[roscoFJ73]

Lately it was getting harder to start, unrelated to the weather, until I couldn't get it to start at all.

Its most likely a problem with air in the fuel injection system and this is what I would eliminate before looking for mechanical or electrical faults.
As the air leak gets worse, it gets hard to start because it takes longer for the pump to push the air through the system.
Air usually gets in around where the fuel line has clamps and around fuel filters.
They dont leak fuel until the leak gets really bad, so dont expect to find wet patches.
Start in the engine bay and work back.

Try pumping the hand pump until it goes hard (I forget where they are on a 13BT). This will often help them start.

 

[Rouke]

Yep, glow screen only. I found mine doesn’t kick on until below freezing ~25ish F or less. I haven't had much issues starting down to 2ish F this year after sitting for a few days.

Sounds like a fuel issue to me. Has the fuel filter been changed in awhile?
These old engines don't need much, air, fuel and compression. Unless you have some very bad compression, I'm leaning more towards fuel. How did it run after starting when it was getting harder and harder to start?

It ran OK for many k's after it started so I don't think it was a fuel (filter) problem, except when it was hard to start it seems to cut off the fuel supply immediately after starting.

 

[Rouke]

One thing just occurred to me. There may be a low oil pressure shutoff.

Oil or diesel? You think it will protect itself against low engine oil pressure? I checked the oil level just the day before and it was OK, doesn't leak or burn oil and the oil pressure gauge on the dash shows normal pressure

 

[Rouke]

My money is on that other goofy thing on the 13B-T... the vacuum actuated shut-off valve.

Try pulling off the vacuum lines going to that flapper valve (it's just above the glow screen on the intake). That will allow the shut down flapper valve to stay open (and prevent you from shutting off the engine with the key) but it will help your diagnose whether you have a leaky or defunct vacuum shut down valve.

Theory of operation... When it is time to shut off the 13B-T, A vacuum solenoid (located under the intake) opens, allowing application of vacuum to actuate the shut down air intake flapper valve, closing off air to the engine, and shutting off the engine. The vacuum solenoid has at least 3 conditions when it will try to shut off the engine - turn ignition key off, low oil pressure, and low manifold intake pressure (presumably because your intake just went underwater... the engine will shut down to prevent hydrolocking, which is good - but if you have dirty air filter, this will also trigger as you are approaching max RPM when trying to merge onto the freeway, which is bad. )

If the solenoid has failed 'open' or some other electrical failure is keeping it open, it will shut down your engine as soon as enough vacuum is built up to trigger the shut down valve, after a few seconds (which matches your problem description)
If the solenoid has failed closed, or you have a vacuum leak in your system, it will be impossible to shut off the engine with the key (this is clearly not your problem, but I share for general knowledge )

Something of that sort sound plausible. It's at the garage right now so i can't check it right now, but will report back when it's been fixed.

 

[Rouke]

I would look at your fuel system, fuel filter. Was it ever sitting for a long time? I’m thinking contamination,
sediment build up

No, I had run it the day before, several times. If it was the fuel filter it wouldn't run at full speed at all, but it when it DID start.

 

[Rouke]

I agree with Behemoth.
Vacuum shut off switch failure produces that same set of symptoms.

But would that gradually get worse? Would I have been able to get it going the first few times when the problem occurred, or is this an all or nothing situation?

 

[Rouke]

Its most likely a problem with air in the fuel injection system and this is what I would eliminate before looking for mechanical or electrical faults.
As the air leak gets worse, it gets hard to start because it takes longer for the pump to push the air through the system.
Air usually gets in around where the fuel line has clamps and around fuel filters.
They dont leak fuel until the leak gets really bad, so dont expect to find wet patches.
Start in the engine bay and work back.

Try pumping the hand pump until it goes hard (I forget where they are on a 13BT). This will often help them start.

Sounds strange that they wouldn't leak fuel but would suck in air. I did pump though, and it increased the time that it kept running from 1 second to perhaps 2 seconds if that. I've noticed rat gnawing on some cables and hoses, but that was evident only recently, whereas the problem started to develop months ago. I don't use it much, only short rides in weekends.

 

[FJBen]

But would that gradually get worse? Would I have been able to get it going the first few times when the problem occurred, or is this an all or nothing situation?

as for shutdown, it can absolutely get worse with time. Mine started taking longer and longer to shutdown before it finally wouldn’t without using the fuel shutoff Or stalling it. Turned out to be an intake gasket leak.

that said, If that sensor is or vacuum port went bad or got plugged, it’s possible it’s always stuck or plugged on shutdown. So as soon as it pulls vacuum it engages shutdown. Would be very easy to watch this with someone starting it and you watching it.

 

[roscoFJ73]

Sounds strange that they wouldn't leak fuel but would suck in air

Not really, because it is syphoning the fuel back to the tank. The fuel lines in this case are under vacuum. Plenty of cases, including mine, are mentioned on this forum. Ive found its often the fuel line that connects to the injection pump or around the fuel filter.

 

[cruiserdan]

Or the primer pump.

 

[Rouke]

My money is on that other goofy thing on the 13B-T... the vacuum actuated shut-off valve.

Try pulling off the vacuum lines going to that flapper valve (it's just above the glow screen on the intake). That will allow the shut down flapper valve to stay open (and prevent you from shutting off the engine with the key) but it will help your diagnose whether you have a leaky or defunct vacuum shut down valve.

You were spot-on! I was in Aussie for a week while the LC was in the garage in New Zealand for repair. When I came back home, the fault hadn't been found and I was advised to tow the LC to a diesel specialist in the 'big city'. But instead I followed your advise, pulled that tube off, turned the ignition et voilà, the engine kept running until I reconnected that tube again. No need for towing! I'll have a look tomorrow to see if I can find what causes the vacuum to be permanently on. In the meantime, is it safe to drive the truck with this tube disconnected? If it's indeed the low oil pressure shut-off, it might not be a good idea to drive it at all, but I had the pressure sender replaced not so long ago because the gauge on the dash board showed a bit low.

Thanks,

Rouke