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rebuild
Posted: Tue Nov 17, 2009 12:24 pm
by cadetchris
probably a daft question,
but would increased fuel and oil consumption, as well as a plume of blue smoke when i accelerate hard, indicate that its time for a cylinder head rebuild?
Posted: Tue Nov 17, 2009 12:25 pm
by ssnjimb
When you accelerate hard blue smoke. Add rings to your list.
Re: rebuild
Posted: Tue Nov 17, 2009 1:08 pm
by PSL184
cadetchris wrote:that its time for a cylinder head rebuild?
Nope - a full engine rebuild

Posted: Tue Nov 17, 2009 4:16 pm
by andrew.searston
bit more than a head rebuild unfortunatly
Posted: Tue Nov 17, 2009 5:03 pm
by cadetchris
i believe the word is "nuts" really not what i can be doing with.
if i remember rightly, its possible to replace the rings with the engine still in, by just dropping the sump, removing the con rods and pushing them up through the block (with the head off or course)
Posted: Tue Nov 17, 2009 5:18 pm
by ssnjimb
Hello Chris
You could try replacing the rings if you want to get a few more miles out of it. Make sure all the breather hoses are unblocked.
Change the oil cap as it is also a breather.
The oil rings could be blocked with gunk.
There is no harm in changing the oil and going from there.
Jamie
Posted: Tue Nov 17, 2009 6:23 pm
by bmcecosse
Run a compression check on the engine. As suggested above - if you make sure one of the breathers is connected to the intake system - either at the carb or directly to the inlet manifold - it can help with oil consumption and blue smoke. Head rebuild will do nothing useful. Try rings if you wish - but - probably money down the pan.
Posted: Tue Nov 17, 2009 6:30 pm
by ssnjimb
I have know this to happen before.
Car with oil that is black and dirty. All breathers blocked up. Dirty Air filter. Blocked dirty oil filter.
Jamie
Posted: Tue Nov 17, 2009 7:17 pm
by cadetchris
ill do a compression check tomorrow morning, as for all the breathers, they are all nice a clear and attached, air filter is new, new oil filter and not that many drips from the bottom of the engine,
what should the compression be?
Posted: Tue Nov 17, 2009 7:24 pm
by ssnjimb
what engine size is it
Posted: Tue Nov 17, 2009 7:24 pm
by cadetchris
1098
Posted: Tue Nov 17, 2009 7:29 pm
by ssnjimb
A range from 130-160 is what you are looking for. i await someone more experianced to correct me

Posted: Tue Nov 17, 2009 9:16 pm
by linearaudio
ssnjimb wrote:A range from 130-160 is what you are looking for. i await someone more experianced to correct me

I reckon he's out playing "trains" tonight

Posted: Tue Nov 17, 2009 9:27 pm
by bmcecosse
Nah - watching Scalextric! I agree - 130 would be about the minimum for a pretty knackered engine - 160 is ok for an average engine - higher is better!
Posted: Tue Nov 17, 2009 9:57 pm
by ssnjimb

i nearly got something right

Posted: Wed Nov 18, 2009 1:46 am
by mike.perry
The Workshop Manual says 150 psi.
Posted: Thu Nov 19, 2009 8:18 pm
by cadetchris
ok, today i did a pressure test, and the results where ad follows:
when running, 70psi and when the engine then is stopped, it jumps to 120psi.
so going by either of these two readings, the compression is a little on the low side
Posted: Thu Nov 19, 2009 10:17 pm
by bmcecosse
I don't understand - when running ?? Compression test is done with all 4 plugs out - engine hot and battery fully charged. Wedge the throttle open slightly - and then put the tester on each plug hole in turn - and crank the engine over on the starter for 3 seconds on each hole. Note the reading - reset the gauge - nd then test the next one. 120 psi is desperately low - if that's done by the above method.
Posted: Fri Nov 20, 2009 11:44 am
by cadetchris
i thonk i may of done the test completly wrong then,
so, i get the engine all nice and hot, with the battery fully charged.
plugs out,
throttle slightly open
attach guage to plug hole, crank over engine a few times with starter only
note pressure
reset guage
next pot along.
so if my engine is good, then it SHOULD be over 130psi min, if its shot and needs a rebuild its below 130psi and is then in need of new rings and gaskets and the valves grinding in again.
ill go do it again and report back with my findings
Posted: Fri Nov 20, 2009 3:15 pm
by katy
when running, 70psi and when the engine then is stopped, it jumps to 120psi.
How exactly did you do this test?