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Old 02-28-2009, 12:05 AM
neilskiw neilskiw is offline
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Default /6 Valves...Hot or Cold?

What is the correct Method?
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Old 02-28-2009, 09:16 PM
moparman92 moparman92 is offline
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You will need 0.009", 0.010", 0.011" feeler gauges for the intakes, and 0.019", 0.020", and 0.021" feeler gauges for the exhaust valves. I usually avoid the "valve tappet feeler gauges" with the bent/angled ends, but they will work if that's what you have. Either way, you will want the large gauges, about ½" wide by a few inches long, not the small ¼" wide type used for setting breaker point gaps. You'll also need a 7/16" wrench to remove the valve cover, and a 3/8" wrench, to adjust the tappets. I use a 3/8" drive, 3/8" socket wrench with a flex head to adjust the tappets, because the flex head helps keep the wrench on the moving adjustor, and in most cases a 3/8" box/open end wrench is too short for good leverage.

Warm the engine up thoroughly. It's best if you can go for a 10-mile drive, but if you can't, then run the engine at a fast idle until full operating temperature is reached. Shut down, pop the valve cover, and start the engine again. Adjust the carbureter idle speed and mixture screws until it's idling very slowly. Plugging the PCV valve with a piece of duct tape will help slow it down. You want it idling on all cylinders, but as slowly as possible without running rough or threatening to stall.

Now, before you start adjusting, notice that in the center of the engine, there are two intakes side by each. The order, whether you're starting at the rear or the front of the engine, is E-I-E-I-E-I-I-E-I-E-I-E. This is important to keep in mind, because it's easy to get caught up alternating intake and exhaust adjustments and forget the two intakes next to each other in the middle, with the result being half the valves adjusted incorrectly.

Put your socket wrench on the first (frontmost) valve, and get used to the wrench jerking up and down. Just hold it loosely in your hand. Before you get into the adjustment procedure, take note of the amount of muscle it takes to move the adjustors. They should be TIGHT, with a genuine "snap" feedback when you manage to turn them. If you can grab the wrench and just turn them whichever way you please with little or no effort, the threads are getting wallowed out and your careful adjustment will not last long. In this case you will need to remove the rocker shaft assembly and do one of two fixes:

• The proper fix: Go get new rocker arms. They're not as easy to find as they once were, but can still be found with some dilligent searching. Usually they come with new adjustment screws, which you'll need. Note that the same rocker is used for '60-'80 Slant-6s, so if you don't think the place you hit will have rockers for a '61 Lancer, ask for them for an '80 Volare. Intake and exhaust rockers are the same, so you'll need 12 (or however many exhibited even slightly loose threads).

• The quick/cheap fix: Remove the adjusting screws and lightly mar the threads with hammer-taps or a squeeze in a vise. Don't go overboard and render them useless. The reason for checking

It's a good idea to take a look and see whether the rocker assembly is oiling properly. With the engine idling, you should see oil dribbling evenly out of the driver's side tip of each rocker arm, and dribbling down onto each pushrod via the rear of each rocker arm. Rev the engine and you should get little spatters of oil flying. Don't expect to see gushing anywhere, but you should definitely have flow up top. If not, you've got some cleanin' to do. Remove the rocker shaft assembly, Dig the endplugs out of the shaft, string all the spacers and rocker arms (minus adjustors) on a steel wire, and take the shaft and strung parts to a machine shop to be hot-tanked. If things aren't so gunky as to require the hot-tank treatment (i.e., you can see oil squirting out of the holes on the ends of each rocker arm) then just use a spray can of Berryman's B12 Chemtool or equivalent carburetor cleaner and a piece of semi-stiff wire to probe and clean the hole in the end of each rocker arm (at the valve end).

Now, on to the adjustment!

Method 1: Select the 0.020" feeler gauge, and slip it between the end of the frontmost (exhaust) rocker arm and the top of the valve stem. Each time the valve opens, the feeler gauge will be clamped tightly between rocker and stem. While the valve is closed, you will be able to slide the gauge in and out. You want a slide-fit, which is tighter than a loose slip-fit, but looser than a tight friction fit. Moving the gauge in and out rapidly in time with the valve opening and closing is a good way to do it. Don't try to get it spot-on, just get it close. Next, move to the intake valve next the exhaust. Repeat the procedure, but use the 0.010" gauge. You want the same kind of fit. If it will be easier for you, go ahead and do all the intakes (with the 0.010) and then all the exhausts (with the 0.020).

Now, after you've done them all, go back and do them again. You will find that some of them (most of them) are not as perfect as you had thought. You can do 4 or 5 of these cycles in a leisurely 45 minutes. Spend the extra time—it's worth it.

When you think you've got it, speed up the engine a bit by operating the throttle with your hand. Do all the valves sound even? None is clacking any louder than the rest? Or maybe they're all still clacking too loudly. This is where all those extra gauges come in handy. If you're not completely confident that you really set the valves to 0.010" and 0.020", you can use the surrounding sizes (0.009", 0.011", 0.019", 0.021") as sort of "check" gauges, where the thinner gauges (0.009", 0.019") should be a loose fit, the on-spec gauge (0.010"/0.020") should be a snug fit, and you should have to fight a little to remove the thicker gauges (0.011", 0.021") gauges once you've inserted them.

The 0.010" and 0.020" adjustment is factory spec for stock cams. Different cams will call for different adjustment specs, and two engines with the same cam may "prefer" different adjustments. If you have a stock or near-stock cam, you'll probably wind up with a final setting of 0.009" to 0.012" intake, 0.019" to 0.024" on the exhaust. Note that 0.012" and 0.024" were specified by the factory for slant-6s used in trucks. The crucial thing is not to overly tighten them, for if you do you'll spoil your engine's performance and economy (intakes too tight), and burn valves (exhausts too tight). But you do have a few thousandths leeway each direction to play with. You'll know if you're holding a valve open because the idle will roughen. You can see this effect by placing an oversize gauge (say, an 0.025" or an 0.013") in between the rocker arm tip and the valve stem tip after it's been adjusted and while the engine is running.

If for some reason you don't want to adjust the valves with the engine running, assemble the same gauges and tools, but also buy a cheap distributor cap. Cut off all six towers and punch out the aluminum inserts. Enlarge each of the six holes. Now, with the engine running, (with the real distributor cap, not this dummy one!) set ignition timing at idle to 0° (TDC). This is after having warmed up the engine. With the valve cover off and the engine shut down, install your new dummy distributor cap. Now turn the engine by pulling the fan and belt so that you can see the rotor under hole number one, which is at about the 4:00 position, and adjust the frontmost 2 valves. (look at the manifolds to see which valve you're adjusting.) Turn the fan so the rotor points to the next hole. The rotor may turn in either direction, depending on how you're turning the engine. If the rotor moves clockwise, the order in which you'll be adjusting your valves is 1-5-3-6-2-4. If the moves anticlockwise, the order is 1-4-2-6-3-5. Remember, 1 is frontmost, 6 is rearmost. Work fast so the engine doesn't cool down too much.
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Old 03-07-2009, 09:34 AM
neilskiw neilskiw is offline
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Default Wow... Thanks!

That is a lot of information to digest. Thanks very much for your obvious expertise, and your time.

And if you ain't eating dirt, you must be leading... right?
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Old 03-08-2009, 05:09 PM
moparman92 moparman92 is offline
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Quote:
Originally Posted by neilskiw View Post
That is a lot of information to digest. Thanks very much for your obvious expertise, and your time.

And if you ain't eating dirt, you must be leading... right?
Depends you can be leading and lapping and still eating dirt. That is info copied and pasted from slantsix.org by a guy called slantsixdan He was the first person I asked when I got my dart and If it was good info so I passed it along.
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