Compression test.....in the right forum this time, doh!

[Pete The Tart]

Well, I always said there was no such thing as a cheap car!!!
I've noticed just recently that my surf is chucking out the odd puss of the dreaded blue smoke, it doesn't seem to do it consistently unless I hit over 4000rpm when all hell brekas loose smoke wise. Bearing in mind that the engine is just coming up to 200,000k's it's not unreasonable to think maybe it needs a bit of tlc, now I want to do a compression test to try and determine if the bores/pistons/rings are the problem, anyone done a comp test on a diesel? I've done loads on petrol engines but diesels be strange beasties!

1:Where do I plug me tester into? Can I use a petrol engine comp tester on a diesel
2:What kind of reading should I expect(on petrol i always reckoned 100psi was nice and healthy, anything less than 75 was buggered and anything more than 10% difference across the bores was dodgy!)
3:To stop the motor firing up on the remaining three cyls I assume I need to remove the gloplugs? injectors? is there a handy lil bypass valve I can turn on?

Basically how the hell do I do it and if I find the comp levels are lovely then where the hell is the smoke coming from? I've discounted valve stem seals as the smoke isn't consistent with them being worn.
And how can I test for potential other sources of the prob, I see someone mentioned turbo seals in another post, what gives?
(Just like beeing a bleedin apprentice again this is, damnit)
Any other suggestions as to where it's coming from?

Apologies for the length

ooer missus
Pete

[NiftyNev]

Pete

A compression tester for a diesel is needed.These are very expensive and would be better to have a diesel specialist do it.Compression on a good engine is up around 450 PSI.

Check intake from turbo to throttle body for excess oil.This will give you an idea on turbo seal condition.

Neville

[gemini]

apart from the compression having to be high on a diesel, its how much pressure is created on the first stroke of the piston, its no good the engine getting to the pressure required if it takes 10 turns of the engine, 90% of it has to be there straight away

[JimL]

Here are instructions from the MaxEllery manual on hilux/runners

COMPRESSION CHECK 'L' Engines (as opposed to R/Y/3VZE which are also detailed in the manual)

1. Make sure of the following:
a) engine is at operating temp
b) battery is at or near full charge
c) remove glow plugs
d) remove fuel pump solenoid connector (this stops both fuel injection and ignition during engine cranking)

2.
a) install compression tester into glow plug hole. Depress accelerator pedal to fully open position and crank engine
b) read compression gauge indication

3. Check remaining cylinders.

Specified compression:
32 kg/cm, 455 pis (psi?), 3,138kPa

Minimum Specified compression:
20 kg/cm, 284 pis, 1,961 kPa

If cylinder compression in 1 or more cylinders is low, pour a small amount of engine oil into the cylinders thru the spark plug holes (max ellery should be shot for this bad text, should be glow plug holes, they keep saying it) and test compression.


Compression Test Results

Normal: Compression builds up quickly and evenly on each cylinder
Piston rings: Compression low on 1st stroke, tending to build up on following strokes, but does not reach normal. Improves considerably with addition of oil.
Valves: Low on 1st stroke and doesnt tend to build up on following strokes. Does not improve much with addition of oil
Head Gasket: If cylinder compression in any 2 adjacent cylinders is low (and if adding oil does not help compression) cylinder head gasket has blown out.


Proviso: I know nothing about compression checking only what I have gleaned from the article I've just transcribed from the Ellery Manual and cant stand over the advice or the figures. Would love to have a tester though coz I'd have a go at it no probs

[Pete The Tart]

Thanks for the input chaps!
I'll be off to see Mr Owner of Expensive Kit next week!
Hopefully it'll be the turbo seals!

[kitesurf_phil]

unless I hit over 4000rpm

No wonder my fuel consumption is so good. I very rarely go over 4000RPM. Have you done the EGR mod' ?
Mine used to chuck out bluey/grey smoke under hard accelleration until I disconnected the EGR valve vacuum tube. I really have to give it loads of welly to produce even the black stuff and the fuel figures are a little better too. I've also noticed that the engine runs a little cooler but still within the normal range.

[Pete The Tart]

Pete

A compression tester for a diesel is needed.These are very expensive and would be better to have a diesel specialist do it.Compression on a good engine is up around 450 PSI.

Check intake from turbo to throttle body for excess oil.This will give you an idea on turbo seal condition.

Neville

Neville,
I checked out the inlet as you suggested and there was enough black sludge in there to get my finger well slimed, almost enough to be called a puddle but not quite. Now if I saw this in an airbox I'd be inclined to attribute it to build up from a small degree of crankase pressure build up, but on a turbo? How much oil if any would you expect to see here?
Also I noticed that the camcover vents into the inlet from airbox to turbo. This seems a silly thing, can I just sling a breather filter on the cam cover and blank the hole in the turbo/airbox manifold? Without affecting the turbo? Your answers anticipated

Cheers
Pete

[NiftyNev]

Neville,
I checked out the inlet as you suggested and there was enough black sludge in there to get my finger well slimed, almost enough to be called a puddle but not quite. Now if I saw this in an airbox I'd be inclined to attribute it to build up from a small degree of crankase pressure build up, but on a turbo? How much oil if any would you expect to see here?
Also I noticed that the camcover vents into the inlet from airbox to turbo. This seems a silly thing, can I just sling a breather filter on the cam cover and blank the hole in the turbo/airbox manifold? Without affecting the turbo? Your answers anticipated

Cheers
Pete

Pete

Remove the intake section that goes over engine to turbo and check how much oil is in this section.If the section after turbo is much oilier than it is more likely to be turbo seals.The intake before turbo will always have a small amount of oil in it because of the breather.Give this a good clean with degreaser before reassembling.The crankcase breather should be connected to the intake system to operate properly.I also think it is illegal to have it vented to the atmosphere.A filter has been made by other Surf owners and this is mounted inline between camcover and intake tube.This is on the list of things to make for mine.

Neville

[gemini]

Pete

Remove the intake section that goes over engine to turbo and check how much oil is in this section.If the section after turbo is much oilier than it is more likely to be turbo seals.The intake before turbo will always have a small amount of oil in it because of the breather.Give this a good clean with degreaser before reassembling.The crankcase breather should be connected to the intake system to operate properly.I also think it is illegal to have it vented to the atmosphere.A filter has been made by other Surf owners and this is mounted inline between camcover and intake tube.This is on the list of things to make for mine.

Neville

Nev, what sort of filter will you be putting in, will it be a wire gauze type as fitted into the old oil filler caps

[NiftyNev]

Nev, what sort of filter will you be putting in, will it be a wire gauze type as fitted into the old oil filler caps

It will be a cylinder of some sort with two hose fittings attached.This will be mounted somewhere convenient and will have a removable top for cleaning.One end of hose from cam cover is attached to bottom and the hose to intake will be at top.This allows oil to collect and drain back to engine.The best thing to put in these is the stainless steel scouring pads that are available at the supermarket.A piece of fine wire mesh should also be installed at both ends to prevent any particles being drawn into the intake or into engine.

Neville

[gemini]

It will be a cylinder of some sort with two hose fittings attached.This will be mounted somewhere convenient and will have a removable top for cleaning.One end of hose from cam cover is attached to bottom and the hose to intake will be at top.This allows oil to collect and drain back to engine.The best thing to put in these is the stainless steel scouring pads that are available at the supermarket.A piece of fine wire mesh should also be installed at both ends to prevent any particles being drawn into the intake or into engine.

Neville

sounds good nev, post us a pic when you've done it