hi guys ,i have a blue 13bt which ive had in a couple of 40 series over last 25 years , engine hasnt done lot -200k , was at tropical sea level for most and now at 800-1500m asl ,ive noticed over time on cold startup (with idle set around 750/800 when warm )idle is too low and stalls and have to use hand throttle until warm ?bit of a pain if others drive it ! any help much apreciated -p.s has no air con or other auxillary gear cheers
13-BT startup idle issues (1 Viewer)
- Thread starter waz40
- Start date
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Its not unnormal for a diesel to have to idle at 1000rom when cold. That's what the hand throttle is for.
Because the pistons are cold, combustion is harder to obtain. As the engine ages, its gets worse.
New injectors may improve it if they haven't been looked at.
Because the pistons are cold, combustion is harder to obtain. As the engine ages, its gets worse.
New injectors may improve it if they haven't been looked at.
- Valve set
- Injection pump timing
- cetane boost fuel additive (especially if in North America)
- injectors (if you have no history)
- block heater (if in cold climate)
Even with all the above looked after, ultimately it is what it is as it's an old mechanical diesel with no cold start advance.
Use the hand throttle to set the RPM when cold starting. Won't be more then a few minutes driving and you will have to dial it back. Though as a transplant it may not have the hand throttle. Retrofit one if not is an option.
hth's
gb
- Injection pump timing
- cetane boost fuel additive (especially if in North America)
- injectors (if you have no history)
- block heater (if in cold climate)
Even with all the above looked after, ultimately it is what it is as it's an old mechanical diesel with no cold start advance.
Use the hand throttle to set the RPM when cold starting. Won't be more then a few minutes driving and you will have to dial it back. Though as a transplant it may not have the hand throttle. Retrofit one if not is an option.
hth's
gb
- Thread starter
- #4
valves have been maintained over the years,has a hand throttle(bj40) i advanced timing on the pump a while back -still runs great when warm . just about to get injectors done , as you said no cold advance and being in altitude now hasnt helped - wasnt sure if adjustment/wear in pump could be causing it ,all good i can still happily live with it the way it is , just looking for input cheers
Nz Nath
SILVER Star
You could bump your idle up a bit, say to 850rpm when warm. That might allow it to idle when cold better.
Do you use your glow screen?
Your theory on the pump isn't impossible. For example the governor springs could set a little. There's also dampers in the manual transmission pump, people with 12hts(similar pump) reckon that can effect the idle and low throttle behavior when they wear.
Do you use your glow screen?
Your theory on the pump isn't impossible. For example the governor springs could set a little. There's also dampers in the manual transmission pump, people with 12hts(similar pump) reckon that can effect the idle and low throttle behavior when they wear.
- Thread starter
- #6
hi nath - thats pretty where iam at with the idle now finding the balance of too high when warm, ive only recently hooked up the intake element as truck was mostly in tropics -needs it now at 800m + asl ,going to look a little bit deeper into pump and how they idled up (without hand throttle)from factory Eg in BJ74 etc -cheers
Nz Nath
SILVER Star
The factory idle up seems to be vaccuum actuated, but has an adjustment screw as well. My 13bt is in a landrover, and missing the idle up and the hand throttle. I've thought about trying to fit the idle up, and using a manual vaccum switch to activate it. Would be handy for using an electric winch whilst out the cab.
Did you find the glow screen helped with the idling? My 13bt won't stay running on winter cold starts without a bit of throttle for the first 10 or 20seconds. Firing the glow screen for 5 seconds would have it start and idle with no throttle. Sounds like your idle issue lasts longer than that though. My warm idle is about 930rpm.
This is a spare/parts pump I got cheap. There is a bit missing that bolts onto the throttle shaft(control lever), that the vaccum actuator pushes against.
Did you find the glow screen helped with the idling? My 13bt won't stay running on winter cold starts without a bit of throttle for the first 10 or 20seconds. Firing the glow screen for 5 seconds would have it start and idle with no throttle. Sounds like your idle issue lasts longer than that though. My warm idle is about 930rpm.
This is a spare/parts pump I got cheap. There is a bit missing that bolts onto the throttle shaft(control lever), that the vaccum actuator pushes against.
- Thread starter
- #8
FJBen
SILVER Star
This, from what I've read, is a standard issue problem for all 13BT's.
I have a rebuilt 13BT, with rebuilt Injector Pump per OEM specs, rebuilt injectors and turbo. Mine does the same thing, idle on cold/cooler mornings is very low and almost won't run. I just use the hand throttle to put around 1,000 until oil pressure is up and good for a minute, then take off unless very cold.
I find once it warms up a little more, the idle creeps up until a little warmer and will settle around 650 when fully warm. I tend to just leave the throttle to have it idle at 750~800 rpms.
My glow screen only kicks on when it gets under freezing. By that time, it's still the same issue with the throttle.
i follow the starting instructions in the manual except for I only do 1/2 pedal when the engine is cold to start. Once warm I don’t need any Pedal to start.
I will say the Idle screw on the injection pump isn’t long enough to even set the idle to a different spring. I’ve heard that from a few people as well.
The injection shop rebuilt to oem specs and set base idle to 650.
I have a rebuilt 13BT, with rebuilt Injector Pump per OEM specs, rebuilt injectors and turbo. Mine does the same thing, idle on cold/cooler mornings is very low and almost won't run. I just use the hand throttle to put around 1,000 until oil pressure is up and good for a minute, then take off unless very cold.
I find once it warms up a little more, the idle creeps up until a little warmer and will settle around 650 when fully warm. I tend to just leave the throttle to have it idle at 750~800 rpms.
My glow screen only kicks on when it gets under freezing. By that time, it's still the same issue with the throttle.
i follow the starting instructions in the manual except for I only do 1/2 pedal when the engine is cold to start. Once warm I don’t need any Pedal to start.
I will say the Idle screw on the injection pump isn’t long enough to even set the idle to a different spring. I’ve heard that from a few people as well.
The injection shop rebuilt to oem specs and set base idle to 650.
- Thread starter
- #10
thanks for that nath -sounds like same symptoms -would like know how that idle up pot is actually setup and works not famiar with how vacuum works in this application -cheers
thanks for that ben !clears
thanks for that ben ,that clears up a lot i have a workshop manual but it doesnt have those starting instructions ,and good to hear your take on it ,i can work with that now , as ive said i had no issue in tropics (instant start- good idle)now in cold area wasnt sure if i was having a declining mechanical issue or not - now seems its common to the 13bt - all good cheers
Nz Nath
SILVER Star
My plan would be to tee into the vaccum feed from alternator to brake booster. The hose coming off the tee could be small diameter, looks like 4mm on the idle up pot. I'd run this into the cab, and have a toggle switch to control it, then from the switch run a line to the actuator. The actuator bolts onto the side of the pump, and when it gets vaccum it pulls the throttle open slightly, the screw+locknut is what engages on the throttle, so you can adjust how much idle up you get.
Just need to get round to finding a switch. Presumably a compressed air switch should also work with vaccum?
That's interesting to read the start up procedure. I'd read other diesels either have pumps that default to full rack with the engine off, or reccomend full throttle. I only use a slight bit of throttle on cold starts, and none at all when warm (to be fair it doesn't really get that cold here in Auckland). The 13bt starts quicker than any modern common rail diesel I've driven.
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