The other day it finally became time to pull the head off the engine. It needed a valve job and It had been blowing white smoke/steam from the exhaust when starting in cold weather.
My hope that it was just a leaking valve seal and bad head gasket was dashed when it turned out that the head is cracked right at the exhaust valves in the middle cylinders.
Getting the head off while the engine is in the car is a pain in the ass.
But I succeeded. It is now at MC Motors where they will grind the cracked part away and weld up a new wall, grind new valve seals, have the valves done, and the bottom planed.
But a couple of questions.
First. Because of the cracks in the head, a little water had gotten into the oil and while not much, how do I best clean it out of the engine?
Second. While dismantling an important step is to loosen the timing chain by removing the plug covering the screw that pulls it back, then turning the screw clockwise to pull the tensioner back. Jan and I tried everything to get the screw to pull the tensioner back, but to no avail. It turns out the the tensioner is very loose as if there is no spring behind it. Also the screw that is supposed to pull it back did not seem to engage and did not move the tensioner at all.
So what could be wrong? My guess is that it is defect, but there was no indication of that when the engine was running. Granted it ran very rough, only firing on 3 cylinders and no vacuum with several hoses cracked.
The oil plan comes off so we can inspect the tensioner and I think the proper thing to do is to just replace it. Anyone with experience here?
Once the engine is running the next big job is to pull the gear box and take it apart. The second gear synchro cone is too small for the synchro ring. Already replaced the synchro ring once and it lasted only a few months before riding against the gear, again grinding when shifting into 2nd. gear.
The plan is to put the second gear wheel on a lathe and take off 1 mm where the synchro ring presses against it, thus allowing the ring to engage the cone more firmly. Alternatively, shave a bit off the side of the synchro ring that rests against the gear, thus also engaging the cone more firmly.
Probably should have pulled the engine out completely to make it easier to get to all the parts.
Last thing first - yes drop the rest of the engine and transmission out, separate them, and then do the engine properly. With the cylinder head work, you need to fit a new water pump, new thermostat, new seals and gaskets and you may as well fit a new vee-belt. Also check the condition of the block core plugs. This is the time to replace any that are suspect. Remember the timing cover must be bolted to the cylinder head before the head face is skimmed (or re-surfaced) - it MUST be exactly the same level. Also remember when you torque the head down, it must be AFTER the timing case is already on and torqued up. (which means the cam gear and chain must already be on and set)
Regarding the timing chain tensioner, whichever type, you must push the screw inwards before you try to turn it. Did you do this? If you tried to turn it before pushing and holding in, either it will not turn or you will break it. Once you have turned it fully until it stops (about 3/4 turn IIRC) it will have compressed the spring and should lock the pad back in that position. I doubt it was lose or faulty because it is such a long chain that if it had been, you would have heard the chain rattling! (and the running would have been poor even without the cracked head) If you remove the sump with the engine still in the car, REMOVE the oil level sensor first otherwise you will probably damage it, and you cannot get them anymore.
With the engine out to strip fully, you can clean the inside of the engine and oil pump/strainer etc. If the cracks are only between the water jacket and the exhaust valves, it is probably that no coolant will have got in the oil anyway. When you drain the oil of an engine where you suspect there may be coolant in the oil, the coolant will always be at the bottom and first out. Oil always lays on the surface of water - remember? So when you release the drain plug always check if any coolant or water comes out first.
Regarding the gearbox, be careful about grinding the sides of gears to get the synchro to work. The synchro mechanism has to lock in place once engaged and if you alter the amount it has to move it may not lock and then the gear may 'jump out' under acceleration.
Roy
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