Sucking in through the breather ? Now fixed

Car is running really quite
bad,won`t idle propperly,and is sucking in air through the rocker cover
breather pipe,it stalls it when i put my finger over it,thats after it
makes a screeching noise,now this morning i moved the cam sprocket with a
spanner,to try and free off the starter.Thought i may have made the
belt slip a tooth or two.
Just been out and checked timing,number 1
at tdc in the middle of the dwell,plug number 1 at firing point on
compression stroke,both marks lined up on crank and int shaft pully.

What
have i done ? Car still performs ok,but it`s sucking in air instead of
blowing it out.
Could i have a bent / sticky valve,or have i done
something terminal ?
With the timing,is it possible it`s trying to suck on the out stroke,and
blow on the in stroke ?
Going to whip the belt off,no cam belt cover
so easy to get too.
Have been giving it a propper ragging,if i am
honest,since getting the last bolt in the cage (not been able to get it
in since fitting it ) it`s transformed the car by about 100% really is
like a roller skate.

have been taking advantage of the dry weather and country roads ..
Did also notice the other day,when
trying to bolt my battery down again,keeps loosening off,that where
there should be a pipe on the airbox,i had blocked this up,but
whatever i blocked it with has come out,might not of helped things.And
just thinking about that now,i hope that didn`t get sucked into the
intake.

Right i did the compression test
1 was at 120 psi
2 was at 110 psi
3
was at 120 psi
4 was at 150 psi

Not sure what to make of
that,test was done dry,with throttle closed
Going to do a wet
test,with full throttle ? is that right,splash of oil in the
bore,throttle open full crank for say 5 turns ?

Right i have been out and done another compression test,dry full throttle crank until gauge stops rising,which happened on 5 turns for each cylinder.
1) 8 bar on the nose
2) 8 bar on the nose
3) 7 bar on the nose
4)10 bar on the nose

Not sure what to make of it really,is it possible that i have a sticky exhaust valve on number 4 ? Or a breached h/gasket....

Oh god !!!!
Took the head off,could not believe how easy the manifolds came off,only took hour and a half.
Downside is the gasket looks fine,i mean new looking,all the metal is intact,does not look more than a couple of years old,i have had it 5 and never touched the head.
If anything,and i am picking hairs here,1 of the head bolts was a couple of pounds less torqued than the others,but only a couple of pounds,surely not enough to cause these readings ?
Been on the phone to an engine builders today,and he didn`t even have a clue what it is.
All components look really clean for 230 thou miles,even combustion chambers ,inside ports etc,valve seats.
Valves all open and snap shut nicely,so really stuck,going to clean the head up with some emery,and check if there are any visible cracks,also been told to check it`s straight with 2 metal rulers.
Re face will be £45 + vat,they can also crack test it for me
Will get a new cam belt,just in case it stretched,but would that not be taken up by the tensioner ? As it still ran the same after taking it off an re setting timing ?

Can anyone recommend an engineering place that will check it for trueness,and give it a skim for me ?
Going to do a leak test with some paraffin.

Its really odd that its sucking in through the breather, even with fairly severe engine problems it still blows and usually when things get bad it blows more hence blowby. Was it quite violently sucking in or could you just about tell it was?

When operating on a strong engine that is still feeding the breather into the intake i would expect it to be sucking as its using the engine vacuum to pull the fumes in?

The only thing I can really think of is a nice big split between valves up to the rockers.... that'd cause it to suck when it got warm
(saw this as a boy on a moggie minor)

or a vacuum leak (major though)

Quote :

When operating on a strong engine that is still feeding the breather
into the intake i would expect it to be sucking as its using the engine
vacuum to pull the fumes in?

Have it going from the rocker cover to a catch tank

Tiz see the vid,it sucks so bad that the car stalls when i block it ! The catch tank was nearly full,but have only been doing short blasts,in it really,so that didn`t concern me,i had not touched any of the intake system .
If i had stretched the cam belt,would it not put things out a bit ? Or would the tensioner compensate,going to give the head a clean with a brass brush in me drill,then will fill chamber with paraffin,and see if it leaks out with valves shut,have had a good close look at it,the haed i sold had splits between the 2 valves,this one looks solid,but will see once it`s clean,next step i will take it to that place on Somersham road,and get a crack test,and then if it`s ok,will get 80 thou ground off it,cant go too far though,or i will deffn have iinterference

Just given the head a de coke,in my kitchen Looked at all the chambers with a mag glass and bright light,noting,all valves are tight in their guides,ports look ok,need a tiny bit of meat taking out,to match to gasket,but all looks ok..
Going to google stretched cam belt,see what comes up

Got this

Quote :

Aftermarket
timing
belts may be used to alter engine performance. OEM timing belts
"will stretch at high rpm, retarding the cam and therefore the
ignition." ^[4] Stronger, aftermarket
belts, will not stretch and the timing is preserved.
^[5] In terms of engine design,
"shortening the width of the timing belt reduce[s] weight and
friction". ^[6]

From here http://wapedia.mobi/en/Timing_belt

Not sure how accurate that statement is

Quote :

Aftermarket
timing
belts may be used to alter engine performance.

Also starting to think now that i should maybe have given the dizzy a twizzle,

Well been a busy boy today,went and bought the correct valve spring compressor,and stripped the head down ready for porting :hugegrin:

All went well,i didn`t go too mad,just smoothed things up a bit,removed the lip from the valve seat insert,matched it to gaskets,and gave it a little polish,all valve guides are nice and tight,not going to bother with the stem seals,only need this engine to last me a few more months..












Why did all the ports have numbers stamped into them ?

Head was slightly lower in one corner,they took 6 thou off it too get it flat.
Turned out there was a blockage in the top of the rocker cover..See the blue T piece,removed that and just ran i pipe too the idle control valve thing..




So i didn`t really need to take the head off,but on the + side i now have a skimmed and ported head,and i also fitted a Janspeed manifold.
It`s really improved my midrange,car has lot`s more grunt now..
Ran out of private test track in the vid,plenty more left,not sure what top end will be,but i think it`s going to be better...



https://www.youtube.com/watch?v=GY-ZvaPvILI


And thinking about it now,i noticed it sucking when i went too empty the catch tank,now i have the catch tank connected too the rocker cover,but the pipe is not the right diameter,so i had it pushed into the large outlet,by an inch or so,this would have more or less blocked the other output,that comes out at a right angle,so when i removed the catch tank pipe it would have let the vacuum escape,causing it to run weak .No sheite sherlock !

And stopping the idle valve from working,easy to deduce now....


I am getting rather Ocd with the valve timing,pulling over every few miles and adjusting the vernier,with it set at the moment ,it revs right up to 7 grand,where as before i am sure it limited at 6,5 ish,think i am going to advance it a tad more,i am currently moving it a mark at a time on the vernier,is that right,or are the adjustments much finer than that ? As i am just guessdimating it,don`t have dial gauge or out fancy,just trial and error