Hi i need expert advice please .i have a mazda 160i i took head of and done valve guides and valve stem seals .i replaced all the gaskets .i then put timming marks in place and then i put the rocker shaft on ...BUT I DIDNT ADJUST THE TAPPETS .IT sound like it want to start but then it dies imediatly .can some one help me please

This is not a "drive way" repair... you need to do one of two things.. sometimes you can get a connector that can replace the spark plug to keep air pressure in the cylinder (THAT CYLINDER MUST BE AT TOP DEAD CENTER ON THE COMPRESSION STROKE!!!!) that will keep the valves closed..( YOU MUST HAVE A LARGE HIGH PRESSURE-HIGH FLOW AIR COMPRESSOR!!!)..now you can remove the valve springs one at a time (have a way to compress the springs??) ..and replace the valve stem seals..one at a time.. IF you DO NOT have the tools to accomplish this, --- YOU CAN REMOVE THE HEADS.. hold the valves in place and remove the valve springs.. and then change the seals, you must have a valve spring compressor to accomplish this.
Does this seem like something you can do..?? If you have never done this??.. PLEASE just pay a qualified professional to change them!! You will need intake gaskets, head gaskets, valve cover gaskets, valve stem seals.. maybe the valves will need re-seating..just to name a few things... get the idea...

Hey Anon..this is a serious problem ONLY if you do not keep your engine oil level full...but you do need to get it repaired as soon as you can..
Sounds like you may only need new valve stem seals...BUT.. you need to check and see if your car smokes when driving.. especially when you are stopped at a red light, then take off again...Does it smoke then.>??? >> THIS IS IMPORTANT!!... It determines whether its rings and/or valve stem seals.. If it smokes after a red light.. it could be rings and valve stem seals.. If it ONLY smokes in the morning.. its a 99% chance its just worn out valve stems seals...
Find a qualified professional (ASE Certified or Toyota Factory shop) ..This is NOT an inexpensive fix..BUT - ASK if they will replace the valve stems seals without removing the heads..( I KNOW they can..its just a matter of WILL they!?!?)...BUT....The shop will want to rework your head(s).. called a "valve job" and this is normal,-- they will remove the head(s), all the valves, regrind their sealing surface and regrind the valve seats in the heads, install new valve stem seals, new intake gaskets, new head gaskets, fresh antifreeze..(get a new -QUALITY- thermostat and have them install it - no need to chance overheating your engine), they should "surface the heads".. giving them a fresh gasket sealing surface.. this will restore the sealing surfaces and help with the compression, and I would recommend letting them do it if you can!!....if you do this -- MAKE SURE you ask/demand for ALL your old parts back,-- all of them!! Good luck,, please mark as/if helpful...thanks!!

no it prob b rocker cover gasket

Hello, there are many reasons for an engine to burn oil. Replacing a head gasket will stop leaks in the head, but it is not a cure all. You can have bad compression, bad oil rings, and valve guides that are worn. A new head gasket can fix compression leaks between cylinders and oil and antifreeze leaks.

Overall bad compression means both the oil rings and power rings are worn out. You can have bad oil rings and still run reasonable well if the power rings are okay. The valve guides are the small seals on the stems and with an overhead cam they are in the heart of the engine. Sometimes when the valley of an engine is plugged up, the oil can not return to the crankcase fast enough. The pooling oil is more apt to lay by the valve stem seals and be drawn into the combustion chamber.

Also check the PCV valve which may snorkel up oil into the induction system. Another sign of bad rings is blowby on the vent pipe.

You have a blown Head Gasket, if you have had leaky Valve Stem Seal the color of the smoke would be blue, for the burning oil. Either way it is more beneficial in the long run to pull the Head off and replace both the Head Gasket and install a re-built Head, instead of doing a Band-Aid repair.

1 Inspect Piston Ring Set Worn or broken piston rings. 2 Inspect Valve Stem Seal Cracked or brittle valve stem seals allowing oil to enter combustion chamber. 3 Inspect Head Gasket - Performance Head gasket leaking coolant into cylinders 4 Inspect Fuel Injector Rich injector 5 Inspect PCV Valve Plugged or damaged pcv valve. 6 Inspect Engine Worn or scored cylinder block 7 Inspect Piston Worn or damaged piston. 8 Inspect Valve Guide Worn valve guides

Hello thank you for choosing FixYa.com here are a few things that would cause the black
smoke and stalling.
1 Inspect Piston Ring Set Worn or broken piston rings. 2 Inspect Valve Stem Seal Cracked or brittle valve stem seals allowing oil to enter combustion chamber. 3 Inspect Head Gasket - Performance Head gasket leaking coolant into cylinders 4 Inspect Fuel Injector Rich injector 5 Inspect PCV Valve Plugged or damaged pcv valve. 6 Inspect Engine Worn or scored cylinder block 7 Inspect Piston Worn or damaged piston. 8 Inspect Valve Guide Worn valve guides

You either have had the wrong valve seals installed, they are physically missing, or the valves are incorrect (too loose in the guides/stem too thin). The rocker arm seals will not contribute to your issue. If it did not have the oil smoke before you took the head off, the issue is with whatever the machine shop did. Valve seals have to fit TIGHT, or oil will go down the valve stem into the intake.
Take the head back to the machine shop & tell them to fix it. For free.

I would replace them if the head is out of the car. Do you have to...no..but if the old ones are leaking you are going to wish you had. and no you did not remove them in your : regular head and valve removel.

Sounds like the excuse is a load of BS to me. If that was the case, the oil would of been burnt off during the normal test drive after they completed the head. I'm assuming you had a blown head gasket?

Blue smoke is indeed oil and if it ONLY occurs at start up then clears itself after some driving, it's the valve stem seals or valve guides (but more likely the stem seals).

They were most likely not replaced during the overhaul.

The stem seals stop oil from the upper lubrication in the head travelling down the valves into the combustion chamber and burning with the fuel.

While the engine is running, there is enough movement in the valvetrain (all the bits that move the valves) so that oil cant make it down into the combustion chamber.

However, when the engine is stopped and left for a period (ie: overnight) oil can trickle down into the combustion chamber through the seals which is why when you first start it up the next day it blows blue smoke. All that gathered oil in the combustion chamber is burning off.

The reason why they probably haven't changed the seals is simple: they make more money.

As a mechanic doing a head you have 2 options: You can either get what's called a 'Headset' which is the head gasket with all the other gaskets involved and stem seals OR you can buy the head gasket by itself and reuse the old gaskets and not replace the stem seals.

The head gasket by itself is half the price of the Headset but you can still charge the customer for the full headset....see where im going? Trust me, this kind of practise is unfortunately very common and one of the reasons I got out of the industry.

Once a car overheats due to a head gasket or any other problem, the stem seals nornally always have to be replaced because they harden due to the heat and lose their sealing power.

The solution? The head has to come off again to replace the seals and these guys probably know it so they are going into BS mode to protect themselves.

You have to insist they fix the problem because it wont go away and don't back down!

Oh, and for future reference there are only 3 kinds of smoke you can get:

Blue = Oil burning
White = Water burning (pretty normal in the morning)
Black = Fuel burning (Mixture running too rich)

Hope this helps :)