red reading
Active Member
because the engine is still trying to compress the other three cylinder's which slow's the starter motor down,therefore giving you a low/false reading
M
mynheers_a_pint
Guest
even so, surly that would effect all the cylinders, not just one? It does puff blue smoke at gear changes and the more boost the worse the puff.
As said, it'll have a leak down test tomorrow. I have noticed a loud ticking noise at low revs. It sort of comes and goes when you touch the throttle. It could be a knackered injector but it seems odd as it is definately coming from the region arround cylinder 1.
Cracked valve maybe?
As said, it'll have a leak down test tomorrow. I have noticed a loud ticking noise at low revs. It sort of comes and goes when you touch the throttle. It could be a knackered injector but it seems odd as it is definately coming from the region arround cylinder 1.
Cracked valve maybe?
red reading
Active Member
if the ring's were fooked it would smoke all the time,if it just puff's smoke on gear changes that would say to me either,valve stem seal's and worn guide's,or leaky turbo seal's,as for the ticking if that was a ring making that noise the car would be pi55ing smoke out the back and eating oil,without hearing or seeing it it's hard to tell,but it could be the valve's need re-shimming,and this could also give you low comp on no1 as the valve's could be held just of there seat's,a leak down test done properly will tell you alot
M
mynheers_a_pint
Guest
well that was my only thought regarding piston rings in that they generally smoke constantly. And from experience, the turbo would cause smoke on over run as well as puffs.
Hmm. I guess i'll know tomorrow.
Hmm. I guess i'll know tomorrow.
davey red.r
New Member
my red r when i bought it had a fooked piston ring, and it only smoked on over run when hot.red reading said:
davey
red reading
Active Member
what worn or broken davey?
M
mynheers_a_pint
Guest
been and had the leak down test....
#drum roll#
ben't/damaged valuve AND cracked piston. air is escaping past a valve and through the cylinder. It could be the ring but i would suspect that the piston and valve had a coming together causing the damage. so new engine time....
****!
#drum roll#
ben't/damaged valuve AND cracked piston. air is escaping past a valve and through the cylinder. It could be the ring but i would suspect that the piston and valve had a coming together causing the damage. so new engine time....
****!
P
pulsarboby
Guest
back from hols now liam, give me a bell as theres a few different options you have.
how can they tell from a leakdown test that you have a bent valve and cracked piston:?
i do not believe that for one minute.
valve will not hit piston unless your timing chain has jumped at least 2 teeth and that cant happen unless it had snapped.
put a spoonfull of engine oil down the plughole on that cylinder and compression test it again straight away and see what readings are;-)
how can they tell from a leakdown test that you have a bent valve and cracked piston:?
i do not believe that for one minute.
valve will not hit piston unless your timing chain has jumped at least 2 teeth and that cant happen unless it had snapped.
put a spoonfull of engine oil down the plughole on that cylinder and compression test it again straight away and see what readings are;-)
red reading
Active Member
did they bore scope then engine then as well to come up with that?
M
mynheers_a_pint
Guest
nah. From speaknig to bob it sounds like an assumtion was made by both me and the mechanic that because air was coming out the air filter a valve was gone as well as the piston. Apparently if the air is getting past the piston it can be blown out of a breather into the induction system.
However the fact remains that i will probably replace the engine if i can find a suitable and preferably overhauled engine to replace it with. My personal thought is that getting a recently rebuilt engine, or even one with 10-20k on, it will generally mean the major consumables such as water pump etc have been replaced which on my engine, they haven't. It makes more sense in the long run as it's les time i need to spend doing it and less cost if i need a garage to do it.
we shall see...
However the fact remains that i will probably replace the engine if i can find a suitable and preferably overhauled engine to replace it with. My personal thought is that getting a recently rebuilt engine, or even one with 10-20k on, it will generally mean the major consumables such as water pump etc have been replaced which on my engine, they haven't. It makes more sense in the long run as it's les time i need to spend doing it and less cost if i need a garage to do it.
we shall see...
red reading
Active Member
fair doo's
pulsarboby said:
If an exhaust valve isn't sealing you'll hear air in the exhaust, Intake valve- you'll hear air in the intake. (Valve could be bent, burnt out slightly or just not sealing properly)
Air in the sump would indicate piston rings,ring land or holed piston.
P
pulsarboby
Guest
yes but in this case what they are saying isnt correct as he's saying that it has a dodgy valve (suggesting the inlet, by air passing induction), and a cracked ring or ringland!!
now that is impossible to tell on a leakdown test alone as the air would pass through the sump and into the breather pipe (which is also connected to the induction pipe to vent gasses) and would therefore pass back through the filter anyway.
liam said that they told him that air was coming from the oil filler cap which suggests its getting back to rocker cover! so once again it will pass into breather system.
so my arguement is that how can he say for sure that it has ring damage and valve damage?????
the easiest and simplest test would be to drop some oil down the plughole and then do a comp test.
if the compression then rises inline with the other cylinders then he would know for sure that its ring / piston related damage.
if the compression was still low then it would be valve damage.
and to suggest that a valve has hit the piston for no apparent reason is wrong (things dont just collide unless theres due cause, ie
a thrown rocker arm which has jammed valve down
broken timing chain or tensioner
broken valve spring
all of these things would make the car run on 3 cylinders only or make it run like a bag of shite which it isnt.
so i ask myself, is it a case of a garage trying to make a big big job out of a job which could be fixed more cheaply!!!
now that is impossible to tell on a leakdown test alone as the air would pass through the sump and into the breather pipe (which is also connected to the induction pipe to vent gasses) and would therefore pass back through the filter anyway.
liam said that they told him that air was coming from the oil filler cap which suggests its getting back to rocker cover! so once again it will pass into breather system.
so my arguement is that how can he say for sure that it has ring damage and valve damage?????
the easiest and simplest test would be to drop some oil down the plughole and then do a comp test.
if the compression then rises inline with the other cylinders then he would know for sure that its ring / piston related damage.
if the compression was still low then it would be valve damage.
and to suggest that a valve has hit the piston for no apparent reason is wrong (things dont just collide unless theres due cause, ie
a thrown rocker arm which has jammed valve down
broken timing chain or tensioner
broken valve spring
all of these things would make the car run on 3 cylinders only or make it run like a bag of shite which it isnt.
so i ask myself, is it a case of a garage trying to make a big big job out of a job which could be fixed more cheaply!!!
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