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Mikuni's 1980 Vauxhall Chevette Wagon


davidian

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^^^ what cam said. Just get head planed, new head gaskit, buy some grinding paste and grind the valves yourself. Only takes a few hours.

I sold one of my old vauxs cause the engine fucked out. 4 weeks later one popped up on trademe. Had been in storage since rebuild as an engine recon place went out of buisness. He only wanted $100 buy now. Gutted really.

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Yeah I was considering 1256 transplant. Would just about be easier than fixing the head. I wouldn't know the first thing about grinding valves, I'd probably make it worse. The heads in getting planed and a valve grind as we speak :twisted: Will try get it going before tomorrow haha.

Anyone got torque settings for a 1256?/just do it up tight bro. Need tappet clearances too.

Oh and a torque rench and feeler guages would be greatly appreicated if someone in hams has some I could borrow. Haha fuk, I come prepared!

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haynes manual (ha i have like 8 different chevette manuals)

tappet clearance in block 0.0006 to 0.0019 in (0.015 to 0048 mm)

Torque wrench settings

Cylinder head bolts 55 lb ft 74 NM

feeler guages are like free to buy anyway, get some then you can pick locks with tthem too

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Cylinder head - reassembly and installation

1 install the valves in their original sequence or if new ones have been purchased, to the seats to which they have been ground.

2 fit new valve stem oil seals and circlips to the four inlet valve guides.

3 insert the first valve into its guide, first having applied engine oil liberally to its stem

4 Fit the valve spring, the retaining cap and then compress the valve spring and locate the split collets in the cut-out of the valve stem. Release the compressor. Repeat these operations on the remaining several valves.

5 When all the valves have been installed, place the cylinder head flat on the bench and using a hammer and a block of wood as an insulator, tap the end of each valve stem to settle the components.

6 Install the rocker balls

7 Install the rocker springs so that the smaller coil is nearer the cylinder head

8 install the rockers and the self locking nuts, only screwing on the nuts a few turns.

9 make sure the faces of the cylinder head and the cylinder block are perfectly clean and then lay a new gasket on the cylinder block so that the word 'front' is visible from above and correctly located. Do not use eny kind of jointing compound

10 lower the cylinder head into position, insert the cylinder head bolts and tighten them to the specified torque and in the sequence shown in fig 1.21

7 4 2 5 9 (side with exhause etc)

10 6 1 3 8

11 each rocker can now be swivelled aside and the respective pushrod installed. apply engine oil to all the rocker components

12 valve clearences should be set with the engine running and hot, as described in section 38, but at this stage they should be adjusted to approximate clearances so that the engine can be started and run. To do this, apply a ring spanner to the crankshaft pully bolt and turn the crankshaft untill no.1 poston is at tdc. This can be established by placing a finger over no.1 plug hole and when compression can be felt, continue turning untill the crankshaft pully pointer is opposite the TDC mark on the timing cover. Insert an 0.008 in. (0.20mm) feeler blade between the end of no.1 valve stem and the rocker and adjust the rocker self-locking nut until the feeler blade is a stiff sliding fit. Repeat the opperation (without moving the crankshaft) on no.2 valve. The clearances for both inlet and exhaust valves are the same

13 Turn the crankshaft until no.3 piston is at TDC and repeat the adjustment procedure on valves 5 and 6 (counting fromt he front of the engine)

14 turn the crankshaft untill no.4 piston is at TDC and repeat the adjustment procedure on valves 7 and 8

15 Turn the crankshaft until no.2 piston is at TDC and repeat the adjustment procedure on valves 3 and 4. IF the foregoing sequence of adjustment is followed, it will prevent the crankshaft from being rotated unnecessarily as the engine firing order is 1-3-4-2

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section 38

Engine adjustment after major overhaul

once at road running temp

6 check and re adjust the valve clearances by the following method: switch off the engine, disconnect the breather hose from the rocker cover, the coil cover, plug leads, distributor cap and slacken the bolt which holds numbers 3 and 4 spark plug leads to the support bracket. Unscrew the rocker cover screws and lift off the cover.

7 Reconnect the ignition components and start the engine. Unscrw the throttle stop screw until the engine runs as slowly as possible.

8 insert a feeler blade (0.008 in/0.20 mm) between each valve stem and its rocker in turn and adjust the rocker nut until the feeler can be withdrawn with a stiff pull

9 adjust the throttle speed screw to give normal idling speed then switch off the engine and refit the rocker cover

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