Sump heater pads

bubblehead

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I have a pair of AD41’s, which on cold start up smoke something rotten, certainly at this time of year or during winter. In summer months they are marginally better but still chuff some smoke out.

Once warm, they don’t smoke at all. They always start well no matter the temperature and always warm up as expected. No further issues. Well serviced etc. subsequent starts per day are always fine with minimal smoke.

I’ve read over and over that it’s just what they do, but I was wondering if anyone has any experience of sump heater pads? I’m wondering if warming the oil an hour or so before first start might help?
 

Poignard

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I have used an electric sump heater for a car engine but that was years ago. You could also but ones that burnt paraffin. Cars don't seem to need them nowadays.

Anyway, if you do an internet search of 'sump heaters', they are available.
 

bubblehead

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Thanks for the reply. Yes I’ve found them available, I just wonder if they will be worthwhile and assist with reducing the smoking on start up. It really does justify a moan from the neighbours.
 

Plum

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I have a pair of AD41’s, which on cold start up smoke something rotten, certainly at this time of year or during winter. In summer months they are marginally better but still chuff some smoke out.

Once warm, they don’t smoke at all. They always start well no matter the temperature and always warm up as expected. No further issues. Well serviced etc. subsequent starts per day are always fine with minimal smoke.

I’ve read over and over that it’s just what they do, but I was wondering if anyone has any experience of sump heater pads? I’m wondering if warming the oil an hour or so before first start might help?
I don't see how hot oil will make any difference to what happens in the combustion chambers at initial startup and your oil cooler will quickly remove that heat from the oil once the engine is running. My 41 (a 41p) emits hardly any smoke at startup even in sub zero temps but does emit some white smoke underway, which I believe is normal.
 
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VicS

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Just a thought - are the heater plugs working? With good compression, a diesel could start in the cold without, but would smoke until it warmed up a bit
I was wondering about that but I think there is only one, presumably in the manifold. It would be a good idea to check it, although if it failed the engine would probably be difficult to start.
 

Stemar

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I was wondering about that but I think there is only one, presumably in the manifold. It would be a good idea to check it, although if it failed the engine would probably be difficult to start.
In that case, I'd think the engines would be more likely to start, but make a lot of smoke in cold weather, than if they had a set of plugs. Is it like the York engine I had in a camper years ago, that dribbled fuel onto a heater in the manifold? If so, it's easily checked.
 

snowbird30ds

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If 41a it will smoke on cold start, it's written in law and warming oil up will make no odds.
I think combustion chamber's changed shape on later models reducing the smoke.
Is there a solenoid operated flap in the exhaust elbow? Is it working? They are known to be wired in the open position in case of jamming and flooding cylinders.
 

neil_s

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I guess the idea is to warm the whole engine up - not just the oil. Maybe a greenhouse heater in the engine room would help?
 

ducked

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You used to be able to get a thing like a Davy lamp (flame behind mesh, so it didn't ignite petrol vapour) for car engine heating, though I'd think it would probably put condensation in it which might be a problem for electrics, perhaps more of an issue for petrol than diesel.

I have an electric coffee pot warmer which I've thought would serve for my car, but I lost parking at my flat so I could no longer get power to it very often. Then I lost the car.

Engine warming not really worth the trouble in Taiwan, though would still probably have done some good.
 

bubblehead

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Thanks for all the replies.
I will certainly look into the heater plugs, will have to locate them first, then look into how to test etc. they do however start very easily no matter the temperature.

As for a solenoid flap, I have no idea. Will take a deeper look and see what I can see.
 

Plum

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Thanks for all the replies.
I will certainly look into the heater plugs, will have to locate them first, then look into how to test etc. they do however start very easily no matter the temperature.

As for a solenoid flap, I have no idea. Will take a deeper look and see what I can see.
If you are refering to the heater plugs (glow plugs) mentioned in post #7 that go in the inlet manifold and need a diesel fuel supply, they were called a thermostart. They helped diesels that were poor starters in cold weather to start, created more exhaust smoke and had no affect on how quick the engine heated up once started.
 
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