I've decided that I've had enough of this oily spark plug pish. Yes I know that I've put up with it for 5 years, and it's not as bad now as it was, but it's getting on my nerves and it's making the engine run evenly. I need to fix it.
Yes, yes, I know the old motto "if it ain't broke, don't fix it", but it'll give me something to do, eh?
So the question is, do I pull the whole engine out, and then fix it? Or, do I pull the heads off with the engine in the car, and see what the damage is?
So first, let's do a wee test. I have a wee run just to warm the car up a bit, and then take out all of the very hot spark plugs past the even hotter exhaust. Then I do a compression test on all cylinders. I have two testers: a "pushy-in" one that you just can't hold in place properly at higher pressures, and a screwy-in one that obviously does. Unfortunately, the hose for the screwy-in one needs to be almost straight to screw in, and you can't get that right angle on all cylinders.
Nevertheless, all the pushy-in readings seem to be around the same, and all the screw-in ones seem to be the same, but a bit higher. A comparison of the two testers on a couple of cylinders, and the push-in one seems to be about 25psi lower.
The main thing, though, is that no cylinders seem to be especially bad, and they're all within a range of 10% or so. The "oily cylinder" is right in the middle of the range. That suggests that there's no fundamental problem, maybe just oil getting past valve guides. We can hope, eh?
With that in mind, I'm not going to pull the engine straight out, I'm going to take the heads off in situ, and see what I find. So - let the trials commence!
Step 1 is to remove the battery and put it away safely. Then I get a bucket and put it under the radiator drain tap, open the tap, take off the radiator cap and drain the coolant.
While that's happening, I take off the alternator supply connection, and the remove the alternator and fan belt, then the alternator bracket from the cylinder head - it has one bolt in the head, and one that also holds on the water pump.
The next things in the way are the carburettors. I remove the air cleaners and then disconnect the fuel supply and the throttle pedal rod. I should really take the carbs off separately, but instead, I manage to get an allen key onto the adaptor plate bolts and take both carbs off as a oner. I notice that the carb linkage to the front carb is loose on the spindle again...
With the water emptied, I pull off the top hose from the radiator and take the thermostat housing and thermostat off. Then I take the heater hose off the front of the inlet manifold.
Next step is to undo the 4 bolts holding on the radiator fan and the water pump pulley - put them aside for now too.
I should have said that I've lined up 2 boxes of zipped freezer bags to label and put all these wee bits in, so that I know (in theory) what goes where when (if) I put it back together.
Then I remove the vacuum hose to the servo and the other one that disappears down to the gearbox. Then I remove rocker covers and disconnect the coil (red and green to +, black to -) and the king lead, and remove the coil and its wee bracket on the manifold. Then I mark the position of No 1 plug lead on the distributor body, take off the plug cap and leads, and set the ignition timing mark to TDC with the rotor arm at No 1. Then I undo the distributor pinch bolt and pull the distributor out of the bloc, watching as the rotor arm turns backwards as it disengages from the skew gears on the camshaft.
There's a breather to the rear of the manifold, with a hose that goes into the passenger side rocker cover. That pulls off. There's also a mushroom tower thing with an electrical connector. I disconnect it, but I'll have to find out what that is before I try to remove it. It doesn't go through the inlet manifold anyway so maybe it can stay. (It turns out to be the oil pressure light sender unit - in the top of the engine!)
Right. Is that us at the inlet manifold now? Good!
The manifold is held on with 12 bolts, 6 each side. I take them all out, starting at the ends and working inwards, and noting if any are
longer or shorter than others. Yes, I've been caught out with that one before!. Here they are laid out in order, front of engine at the
bottom. 3 of them are longer than others, so I note the order. I also note that the bottom threads are thick with sealer so I'm not
expecting an easy removal!
I also have to take out the coolant temperature sensor to get to one of the bolts.
So with all the bolts undone it should lift out. Except it doesn't - it won't budge at all. I try levering it on bits of the casting, but nope, no cigar.
It's getting late so I decide to leave it while I recharge my enthusiasm.
So this is what I have removed so far.
and this is what's left!
The next step is to find a tame gorilla to prise the manifold off the engine. I'll speak to Dave tomorrow.