Volvo 2020 Concern Part 2

Lucky Duck

Lucky Duck

Well-Known Member
Joined
9 Jun 2009
Messages
8,780
Location
From the Needles to the Nab, from Cowes to St Kats
Visit site
Many thanks to everybody who replied or PM'd me regarding the problems I was experiancing with my engine - in this thread http://www.ybw.com/forums/showthread.php?364809-Volvo-2020-Concern&highlight=

I have now elimated the glow plugs as a possible cause of why one of the cylinders not always firing (mostly when the engine is cold).

When the problem cyclinder is working there is a very pronouced 'ticking' noise audible when the engine is at idle or at low revs. Once some throttle is applied the noise appears to dissapear. The exhaust also seem louder than I remember.

Could this be caused by a problem with the injector?
 
Brent Goose said:
Many thanks to everybody who replied or PM'd me regarding the problems I was experiancing with my engine - in this thread http://www.ybw.com/forums/showthread.php?364809-Volvo-2020-Concern&highlight=

I have now elimated the glow plugs as a possible cause of why one of the cylinders not always firing (mostly when the engine is cold).

When the problem cyclinder is working there is a very pronouced 'ticking' noise audible when the engine is at idle or at low revs. Once some throttle is applied the noise appears to dissapear. The exhaust also seem louder than I remember.

Could this be caused by a problem with the injector?
Click to expand...

Corroded exhaust valve and seat from sea water contamination . Check the compression. No need for a compression gauge if it is this. A thumb in the injector pocket will confirm it :D
 
It would help the diagnosis if you told us what could be eliminated as the result of your previous investigations. Ticking from the top end could be a loose tappet. Open the oil filler cap to detect if it sounds louder.
 
Vyv,

I thought I could elimated the glow plugs when I 'lost' the offending cylinder when dropping down to idle revs after a good six hour run. A quick burst of throttle brought it back into action.

When the engine is started using the standard procedure it will fire on two of the clylinders but needs the throttle to be applied to bring the final one 'on line'. It is immediately obvious when this happends as the white smoke stops and this 'ticking' noise can be heard.

Whilst running at cruising revs (around 2,500rpm) the is a small amount of white smoke which I don't recall being present beforehand.

The problem appears to be getting worse which also suggests to be it is not a glow plug issue.

I had the local Volvo engineers down twice to look at the problem but came back both times with 'no fault found'
 
I agree, cannot possibly be the glow plugs. Bilgediver's suggestion well worth looking at. Bar the engine over to try to detect a difference in compression. You need to do it with the rocker cover off to know which cylinder is on compression. One simple little trick that works well is to slacken each nut connecting the fuel line to the injector in turn while the engine is running in two cylinder mode. The one that has no effect is the faulty cylinder.
 
If you're running with one of the injector feeds disconnected, keep your hands away from the pipe as the high pressure squirt of fuel may penetrate skin! Best to wear sturdy gloves.

It sounds like you could have an improper spray pattern from one of the injectors, causing incomplete combustion at normal revs and not sufficiently atomized to ignite at tickover. If so, the cure is simply to remove the injector and take it to a diesel fitter to have it cleaned and reset - might as well do all of them, it should rejunenate the engine!

Rob.
 
rob2 said:
It sounds like you could have an improper spray pattern from one of the injectors, causing incomplete combustion at normal revs and not sufficiently atomized to ignite at tickover. If so, the cure is simply to remove the injector and take it to a diesel fitter to have it cleaned and reset - might as well do all of them, it should rejunenate the engine!

Rob.
Click to expand...

Just had the report back from the injector people and this is exactly the problem. The good news is that they should be fixed and re-fitted in time for the weekend.

Once again, many thanks to everybody who replied.
 
Brent Goose said:
Is is an easy fix or a major job?
Click to expand...

It is a head off job and if lucky just a clean up of valves and seats. If bad then maybe a new seat insert. Some of these engines have been poorly installed and might have benefited from high rise exhaust bends. Is there any chance on your boat of residual water between the bend and water trap running back when the engine is stopped. In some cases I have seen the water trap has been mounted too high over the shaft.
 
Can you let us know who did your injectors? I'm on the Orwell with an MD2010 which is getting a bit of TLC. See my post on the East Coast forum by the way. Cheers Jerry
 
Bilgediver said:
It is a head off job and if lucky just a clean up of valves and seats. If bad then maybe a new seat insert. Some of these engines have been poorly installed and might have benefited from high rise exhaust bends. Is there any chance on your boat of residual water between the bend and water trap running back when the engine is stopped. In some cases I have seen the water trap has been mounted too high over the shaft.
Click to expand...

Hopefully having the injectors serviced will have sorted the issue but have this nagging feeling you might also bee right as I somehow succeeded to get water in one of the cylinders when I tried to start the engine for the first time the season. Fortunately it managed to get it sorted with a couple of hours so fingers crossed no long term harm done.
 
rob2 said:
If you're running with one of the injector feeds disconnected, keep your hands away from the pipe as the high pressure squirt of fuel may penetrate skin! Best to wear sturdy gloves.
Click to expand...

I have done the slackening injectors trick many times, on both diesel and gasoline engines, and never managed to achieve even the slightest pressurised squirt of fuel. A quarter turn of the nut is usually enough to release the pressure by opening the flared joint inside. The fuel dribbles out, the squirt having been damped by the screw threads.
 
vyv_cox said:
I have done the slackening injectors trick many times, on both diesel and gasoline engines, and never managed to achieve even the slightest pressurised squirt of fuel. A quarter turn of the nut is usually enough to release the pressure by opening the flared joint inside. The fuel dribbles out, the squirt having been damped by the screw threads.
Click to expand...
True, this is the recognised way of checking, maybe not such a good idea on a common rail diesel though? Did this on a Focus diesel with an electronic pump which was faulty and fuel still came out, a bit confusing!
 
Brent Goose said:
Hopefully having the injectors serviced will have sorted the issue but have this nagging feeling you might also bee right as I somehow succeeded to get water in one of the cylinders when I tried to start the engine for the first time the season. Fortunately it managed to get it sorted with a couple of hours so fingers crossed no long term harm done.
Click to expand...

Bad news, I am told the new injectors haven't solved the knocking/tickign noise and contary to my original theories this can't be isolated to a single cyclinder.

Not sure where to go from here :(
 
Brent Goose said:
Bad news, I am told the new injectors haven't solved the knocking/tickign noise and contary to my original theories this can't be isolated to a single cyclinder.

Not sure where to go from here :(
Click to expand...

Any more info....Why do you say can not be isolated to a single cylinder? Have you tried running the engine and slacking of the injector pipe nuts one at a time to see if there is any perceptable difference in performance whn one particular cylinder has its fuel cut off. The cylinder which cases no difference or little difference when the fuel is cut off will be the faulty one and often this is the one nearest the gearbox.

Are you saying that no matter which injector nut is slackened off the engine slows down the same amount.

Have you tried using a sound rod such as a large screwdriver to see where on the engine the ticking is coming from. Even running with the tappet cover off can help identify the source.
 
Hi,

Unfortunately this is second hand as I'm at work right now, but I am told that there wasn't any perceptable difference when each cylinder had it's fuel cut off.

I will go down to the boat this evening and see if I can learn anything more.

The knocking sound isn't a problem to me in itself but my concern is that using the engine is causing further damage and it will then fail at an inopportune & expensive moment.
 
You must log in or register to reply here.

Share this page

Top