White smoke

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Jonathancilia
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Re: White smoke

Post by Jonathancilia »

I replaced the bosch injector nozzles, one of them was completely blocked with carbon. The hole that the diesel passes from in the cylinder head ! Will report back with resulta later on the smoke

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CitroJim
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Re: White smoke

Post by CitroJim »

Jonathancilia wrote:
20 Jan 2021, 17:17
I replaced the bosch injector nozzles, one of them was completely blocked with carbon. The hole that the diesel passes from in the cylinder head ! Will report back with resulta later on the smoke
Fingers crossed
🤞

Jonathancilia
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Re: White smoke

Post by Jonathancilia »

White smoke seems to have stopped, its still smoking abit black under load only, however starting issue is still there, takes ages to start when cold, we are going to try to replace the glow plugs, also car battery doesnt seem to be doing good, its not turning fast as it should seems to be struggling, maybe the slower turning rate of engine is affecting starting too. When you push start it starts and runs fine then

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CitroJim
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Re: White smoke

Post by CitroJim »

That's good news... A little black smoke under heavy load is normal but hard staring is not...

The starting problem, if it remains after eliminating the glowplugs as a cause, still points to low compression...

Have you checked the valve clearances? Some diesel PSA engines have their tightest valve clearances when stone-cold and this is a known cause of hard cold starting with white smoke. Once the engine warms a little the clearances open up enough for the engine to run more or less normally...

Jonathancilia
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Re: White smoke

Post by Jonathancilia »

Could be worth a check, what are the tolerances of the valves so we check after the glow plugs? I have a set of feeler gauges, and how do we adjuts, with shims?

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Re: White smoke

Post by Jonathancilia »

The priming device thats installed is not oem, i think its leaking because i took out the fuel hose, pumped the primer and put my finger on the hose, slowly it leaked and returned to normal, not hard

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white exec
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Re: White smoke

Post by white exec »

The priming device should incorporate a non-return valve; possible that that has gone leaky.
The priming bulb should remain solid for a good while after priming if you don't start the engine. If the engine is started, fuel will be drawn towards the fuel filter and injection pump, and the pressure created by the priming will fall as the injection pump sucks fuel from the tank.

Jonathancilia
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Re: White smoke

Post by Jonathancilia »

If i dont start the engine and i prime the device it stays hard for a few seconds then it gets soft to press again. There is a non return valve fitted on the inlet and its working because i tested it. One thing i noticed now i dont know if this could be the leaking area. The outlet on the bosch pump i removed the hose from it, put my finger infront of the port, primed the device and it stayed hard indefinitely not like before, i replaced the fuel hose from the outlet of the pump to the diesel line that goes to the tank and the priming device still gets soft after a few seconds. There should be a non return valve fitted to this line or no? As there isnt at the momeny

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Re: White smoke

Post by Jonathancilia »

https://www.lsforklifts.com/p538900/hys ... s5477.html

The priming device on the car currently is like the one in the first picture on the website i put

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white exec
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Re: White smoke

Post by white exec »

There are actually two pumps inside a Bosch injection pump.

The first one's job is simply to suck fuel from the tank (via any priming device and fuel filter). It doesn't develop any huge suction/pressure, and its function is simply to keep the inner chambers of the pump full with fuel.

The second pump is the High Pressure/distributor one, which develops huge pressure, and feeds it to each of the four injectors in turn in accurately timed and measured quantities (injection).

The first (primary) pump keeps the innards full, and to avoid excessive internal pressure there is an 'escape' return feed from the pump back to the tank. This also prevents the fuel in pump from getting excessively hot (by sitting in there and the supply lines for too long), and has a minor benefit of slightly warming the contents of the fuel tank in very cold weather.

The return to the tank is controlled to a gradual pace by a small-bore constriction in the pump return outlet, and this not only slows the fuel flow down, but also controls the primary pressure inside the pump. It is important that this small aperture doesn't get blocked (they normally don't), and is NOT in any way compromised by having any sort of non-return valve there or after it. After the restriction, it needs free flow back to the tank.

By blocking the return to the tank with your finger, and feeling the priming pump go/remain solid, what you have done is to show that the fuel return is working properly. The constriction drilling is very small, and there is a limit to how fast fuel can be pushed through it - which is why rapid squeezing of the priming bulb feels solid, but gradual/intermittent priming feels much less so.

There should only be non-return valves on the INTAKE side of the pump. These are there to stop fuel flowing back to the tank (and risk leaving an empty pump, so poor starting). The non-return valves can be in the fuel filter (some have two) and in the priming bulb, whose action definitely needs to be one-way forward!

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Re: White smoke

Post by Jonathancilia »

Ok gotcha so my outlet is free flowing, and valve is on the intake side, now we will see in the morning if it starts lol, mew glow plugs were put in it.starter motor seems lazy, it was turning the engine when we tried but was turning slower than normal

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white exec
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Re: White smoke

Post by white exec »

Slow/lazy starter motor - check main battery connections: if either terminal/clamp gets at all warm during cranking, replace the clamps with new brass ones, as they have acquired resistance internally.
Check also main battery-engine/gearbox-chassis main earth/ground cable for clean connections, and main Batt+ connection to the starter solenoid.
Use a second (jump-start) battery as well. If that speeds things up, replace the battery.

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Re: White smoke

Post by harryp »

Just "found" this. Interesting regarding the blocked injector causing white smoke.
I had to repair a Dunlop Brake Booster as it was drawing in brake fluid into the engine. Looked for all the world like dense fog.
T'was on Daimler Dart. :shock:
Regards

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CitroJim
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Re: White smoke

Post by CitroJim »

harryp wrote:
21 Jan 2021, 19:07
Just "found" this. Interesting regarding the blocked injector causing white smoke.
I had to repair a Dunlop Brake Booster as it was drawing in brake fluid into the engine. Looked for all the world like dense fog.
T'was on Daimler Dart. :shock:
Regards
I had that happen on an old Volvo 340 Harry, I kept wondering why the master cylinder reservoir needed topping up so often :roll:

It can't happen on a diesel as they always have a small vacuum pump for the brake servo as diesel engines don't develop a manifold vacuum as a petrol engine does...

Jonathancilia
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Re: White smoke

Post by Jonathancilia »

That happened to my lada aswell, no leaks anywhere and i thought to myself where it is leaking into lol, then i openee up the brake booster because i had it leaking air too and yup there it was caked with brake fluid haha