help miss firing and white smoke

oldskool · Oct 19, 2012

evening all

need some help had a p38 diesle brought in on a transporter today suffering from poor starting,
misfiring at idle and part throttle,
knocking (diesle knock)
lots of white smoke and cuts out when put in gear (auto) any help would be gratefully received

rodntod · Oct 19, 2012

oldskool said:
evening all need some help had a p38 diesle brought in on a transporter today suffering from poor starting,
misfiring at idle and part throttle,
knocking (diesle knock)
lots of white smoke and cuts out when put in gear (auto) any help would be gratefully received

Water or some other contaminant in the fuel,or signs of a failing cyl head gskt

wammers · Oct 19, 2012

Has someone put petrol in it? Water in fuel. ???

oldskool · Oct 19, 2012

rodntod said:
Water or some other contaminant in the fuel

Yer i was thinking along those lines as i have removed the filter and although it looks like diesle it doesn't smell to much like diesle don'tthink owner is telling me full story

cheongthong · Oct 19, 2012

when was the last time you change your fuel filter ?

oldskool · Oct 19, 2012

wammers said:
Has someone put petrol in it? Water in fuel. ???

Doesn't smell like petrol to be honest smells a bit like stagnant water

but didn't have time tonight to investigate it further a job for tommorow

wammers · Oct 19, 2012

oldskool said:
Doesn't smell like petrol to be honest smells a bit like stagnant water but didn't have time tonight to investigate it further a job for tommorow

Turps or something like that then. Get a gallon of diesel and feed it from that see if it clears. Is it using coolant?

sandyt · Oct 20, 2012

Bet he bought some cheap contaminated diesel

Datatek · Oct 20, 2012

Has it had veggie oil in it or home badly made bio diesel?

oldskool · Oct 20, 2012

ok ran it on some clean diesle from a can today and its no better

sounded like it was back firing up the inlet manifold

removed cam cover and inlet manifold.

The problem is with cylinder 6, inlet port is dry and sooty,
when its cranked over its blowing out of the inlet valve when it opens.

Im assuming these are hydraulic tappets? it seems like the exhaust valve isn't opening, any thoughts any one

wammers · Oct 20, 2012

oldskool said:
ok ran it on some clean diesle from a can today and its no better sounded like it was back firing up the inlet manifold removed cam cover and inlet manifold.

The problem is with cylinder 6, inlet port is dry and sooty,
when its cranked over its blowing out of the inlet valve when it opens.

Im assuming these are hydraulic tappets? it seems like the exhaust valve isn't opening, any thoughts any one

They are hydraulic. Maybe the tappet has collapsed internally due to **** on the ball valve. Does number 6 exhaust appear to be lower than the others?

Datatek · Oct 20, 2012

Not sure how the exhaust valve not opening would give you white smoke out of the exhaust?

09keithpayne · Oct 20, 2012

is the timing out? mine had similar issues with the misfire and throttle and turned out to be that. mines a 300tdi manual disco so i could be wrong.What does the smoke smell like

oldskool · Oct 20, 2012

wammers said:
They are hydraulic. Maybe the tappet has collapsed internally due to **** on the ball valve. Does number 6 exhaust appear to be lower than the others?

No its the same hight as the inlet and i cant compress it but i may no be pushing hard enough, i thought the same possibly a soft tappet gonna pull the exhaust manifold off monday if owner gives me the ok so i can see if the valve is actually moving was just wondering if this was a known problem with this engine.

Cheers for your input wammers

oldskool · Oct 20, 2012

Datatek said:
Not sure how the exhaust valve not opening would give you white smoke out of the exhaust?

Was white/grey last night, more black now which is what i would expect with all the muck coming out f cyl 6 effectively large amounts of EGR

oldskool · Oct 20, 2012

09keithpayne said:
is the timing out? mine had similar issues with the misfire and throttle and turned out to be that. mines a 300tdi manual disco so i could be wrong.What does the smoke smell like

No its not the timing but thanks anyway

Datatek · Oct 20, 2012

If the exhaust valve is not opening and the cam lobe is still there, either the hydraulic tappet is fubarred or the valve has seized. Is the valve definately closed?

oldskool · Oct 20, 2012

Datatek said:
If the exhaust valve is not opening and the cam lobe is still there, either the hydraulic tappet is fubarred or the valve has seized. Is the valve definately closed?

Tappet moves when engine turned over im thinking bad tappet, will be having ex manifold off monday if the owner gives me the ok to carry out further investigation.

Its the only thing i can think of that would cause the problem it has, blowing out of the inlet port.

Are the tappets a known problem on these engines??

Datatek · Oct 20, 2012

oldskool said:
Tappet moves when engine turned over im thinking bad tappet, will be having ex manifold off monday if the owner gives me the ok to carry out further investigation.

Its the only thing i can think of that would cause the problem it has, blowing out of the inlet port.

Are the tappets a known problem on these engines??

Can you push the valve down manually? Not sure taking the exhaust manifold off will help unless you need to take the head off and it's not that easy to remove.

oldskool · Oct 20, 2012

Datatek said:
Can you push the valve down manually? Not sure taking the exhaust manifold off will help unless you need to take the head off and it's not that easy to remove.

Tried compressing tappet earlier but it didn't appear to want to compress, not easily anyway.

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