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  #1  
Old 03-28-2001, 10:27 PM
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250 Engine Ressurection - 3

Christy,

Here's how to hand crank the engine. I've written it so anybody searching the archives can use the info. Sorry to repeat some of what you already know.

First off, tools required:

- A 28mm (or 1 1/8") socket. Sears and Home depot sell it as a 1/2" drive, 12 point socket.
- A 3" (give or take a little) extension rod.
- A breaker bar (long handle sucker. Mine is about 3 foot). Longer is better than shorter.
- TWO 10mm combination end wrenches; MUST have a 6-point closed end, NOT 12-point (which means sears, not home depo).

OK, get out the 108-109-111-113 manual and turn to page 00-1/9.
Here, you'll see two pictures of an engine, not unlike yours. The first, R00-5106 (read the fine print at the bottom of each picture), shows the fan on the left and you can just make out the pulley on the crankshaft below the fan. The other picture, R00-5107 shows the pulley more clearly.

A few pages back, on 00-1/3, you can plainly see the pulley and the bolt you're looking for. Of course, this is a 3.5l v8, but the idea is the same.

Your first goal is to convince the socket to fit over that bolt there on the crankshaft. I find it a lot easier to be flat on your back and reach up from the bottom for this. Also, be sure to put the extension on the socket, but leave off the breaker bar. It's a lot easier to just do the socket all by itself.

Now that the socket is on the bolt, attach the breaker bar to the socket. Here, you have a choice, have the breaker bar point down to the ground, or up to the sky. If you choose up, the fan is going to be in your way; remove it.

To remove the fan, loosen by one quarter turn each of the four bolts that holds the fan to the pulley on the water pump. Since the bolts are tight and you can't hold the fan still (good ol' hydraulic clutch), use one of the 10mm box end wrenches to hold a still-tight nut while you loose another. To do the last nut, you're going to tighten one of the loose ones, but that's OK, since it won't be all that tight and you can loosen it again by hand.

Now that all four bolts are loose, you can remove them, remove the fan, and then put the bolts back so the pulley doesn't fall off and take the belts with it. Yes, you can start the car this way (assuming you get the car to a state where it will start). Don't drive it long or let it idle for long like this, since there is no fan to cool it down).

With the breaker bar in place, you can now hand crank the engine a little. If you do it with the plugs in place, you'll find that it takes elbow grease. Take some or all the plugs out to make it easy.

-CTH

PS. The 28mm socket is for all the '60s straight 6 motors EXCEPT the M189. For that one, you'll need to get a 32mm socket and weld a toung made from steel inside it to make a mondo screw driver. I recall the steel I used being 1/4", but you'll have to measure it. For the M110, M116 & M117 motors, you'll need a 27mm socket. For the M100, a 2" socket is required. Sears sells one with 3/4" drive, so you'll also need their 1/2" to 3/4" converter.

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  #2  
Old 03-31-2001, 04:40 PM
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this car....

Hi guys!

You all wouldn't believe how DIRTY I am!! I MEAN, I've been working on this car ALL DAY!

First off...the oil change. Can you believe that there was nearly 3 gallons of fuel and oil in there??!! *woof* A little grit..nothing too exciting..

Next...all new plugs...perfectly gapped...nice and sparky!
As you should know...the car has all new cap, rotor, plug wires...points are also perfectly gapped...dwell? It's all good...

SO.....did it start??? NO!!

Tried Chuck's idea of moving the distributor around to advance/retard the timing....didn't matter..(in this case)..

Also...re-tried the ether test...no good..just stinky..

So..what's the car DOING??? The car TRIES to start, really, I think. It slightly coughs, and chuggs somewhat, but of course, never starts..

So...maybe the charge isn't strong enough??? Ignition coil?? This coil DOES look pretty OLD. EVERYTHING else ignition related seems wonderful....

I also tried undoing the fuel lines to the carbs, and cranking it again to see if it helped (because before it seemed to help)...well today, it made no difference....

Is it a fuel problem?????

I don't know....that CLIFF is sounding real good right about now....

~Christy
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  #3  
Old 03-31-2001, 05:18 PM
brianguy
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Since you have cranked the motor with the fuel lines disconnected you have probably determined that you have
fuel being delivered to the carbs if that is true,do you have spark? Just because you have all new ignition parts don't assume you have spark.Remove a sparkplug reconnect the plug wire and ground the plug to the engine block have someone crank the motor watch for spark(dont touch the wire or you could get a shock)if you have spark and fuel it should fire it might not run but it should at least fire.
All most all situations where an engine will not start involve the absence of fuel or spark (or both)A complete loss of compression is another reason.
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Old 03-31-2001, 06:58 PM
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OK, having wiggled the distributor, your first loosened the bolt that held it (I hope)? If you didn't need to loosen it first, then that is trouble. Having moved it and
"put it back", are you sure you have the correct setting on the distributor? Having it off by as little as 10 degrees (one wig of a wiggle?) will make it not start.

To hand set the distributor, you're going to have to:

1. Hand crank cylinder #1 to TDC.
2. Timing light in hand, and the igition turned on.
3. Position the distributor so that the light blinks.
This isn't quite as easy as it sounds.
4. Check the timing at "starter speed" to be at 0.

-CTH

PS. Hope Dad is still there.
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  #5  
Old 03-31-2001, 08:44 PM
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Ok...

Brian...I now definately have STRONG spark. A good question is whether or not it's sparking at the right time...

CTH....this is soooo over my head!! I'm still struggling with firing order!
About the distributor, YES we (me & Dad) loosened the bolt, and tried it in different spots...we just put it back where we started, which was right in the middle....

Here's what I'm doing now....I've taken off the valve cover. Purpose?? To gain access to the 4 bolts on the engine side, that hold on the carburetors....
...YES, I have taken off the carburetors COMPLETELY!!
I'm probably CRAZY...but I'm going to do the job right and completely overhaul these things....The engine is getting TOO MUCH FUEL....I'm pretty convinced....AND have NO IDEA why!!!!????

So...try not to be too irritated that I keep jumping from thing to thing....I'm just trying to do what I think I can and gain the confidence to try the rest!!

BTW....new problem...a few times today, when I went to turn the key inside the ignition, NOTHING happened AND the battery was NOT dead!!!!! Also, if I just turned it back off, and tried again, it would work....Do I have some fried out wire, or something???? *sigh*

~Christy

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  #6  
Old 04-01-2001, 10:26 AM
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Couple of quickie comments:

(1) When working on the fan or cranking the motor by hand, it is ALWAYS a good idea to remove the battery terminal. If that sucker starts, you'll loose an arm.

(2) I've cranked my 4.5 M117 engine with the wooden end of a hammer handle. I wedge it in the "hollow" of the pully. If it's the correct size, it will get a grip on the side and you can slide the engine around about 10 degrees at a time. This way you don't have to remove the front fan.

Probably late on these.

Sholin
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  #7  
Old 04-01-2001, 12:24 PM
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Sholin,

On your 117, you can roll it over without having to remove anything. BUT, it is a tight fit. 27mm socket on a short extension, work it in near the A/C compressor as there is a small recess in the shroud and the shroud will flex a little. Might need to turn the fan a tad for extra clearance, since the blades are unevenly spaced. Again it's a tight squeeze, but once the socket and shorty extension are in place (and you have to do this by feel), come in with a breaker bar, pull the drive all the way down, perpendicular to the bar and set it in the extension. You can get almost 45 degree rotation, but have to repeat the process to get any more.

All of this is done from beneath the car.

I think the damper ring on the crank pully is a combination of aluminum and hard rubber, someone will correct me if wrong, but I wouldn't push/pull/pry on that ring.
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  #8  
Old 04-01-2001, 04:14 PM
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Zenith carburetors....

Ok....Here come some carburetor questions...

As I've mentioned, I took both of these carburetors off of this car. I haven't even started anything with them, but was just inspecting them.
Now..Does anyone know what the throttle (?) plates on the VERY bottom of the carburetor is supposed to do? I am trying to understand how it works...
When I turn the carburetor upside down, there are 2 of those flaps on the very bottom. One opens easily when the linkage bar is pulled back. The other flap has a bar that appears to go to the vacuum "circle" (that says Zenith on it). Is it SUPPOSED to open?? Ever?? Common sense tells me it should, since IT IS a flap...BUT on both of my carburetors, this flap doesn't open. If it helps, the flap that doesn't open, is the really dirty one...

Does anyone know what the hell I'm talking about??

~Christy
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  #9  
Old 04-01-2001, 06:40 PM
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You're talking about the primary and secondary trottles on the carb.

The primary (smaller) throttle plate is directly linked to the accelerator pedal. The more you press your foot, the wider it opens. More open means more air.

The secondary (larger) throttle plate is controlled by that big mushroom at the back of the carb. Its diaphram is controlled by vacuum. You don't see the vacuum passages, since they're inside the carb. The mushroom is held down with three screws. Buried in there is the vacuum passage. The secondary only starts to open as the car is running pretty hot & heavy.

In all seriousness, assume that that part works, since (1) it doesn't have any affect at idle so it's not in your "critical path" and (2) If it's assembled correctly and the various passages are clean, then, it works.

Now, the foot controls the amount of air that gets in the carb, AND NOTHING ELSE, almost. It also causes the acceleration pump to dump about 1cc of gasoline right down the throat of the primary to help accelerate. All the bores inside the carb are used to route air from the trottle bore into the carb body. The result is changes to the air pressure inside the carb and like a straw inside a milkshake, stuff moves.

There's a lot of science to it, none of which, I particularly ever care about. You can look up the Bernoulli brothers from the late 1700's if you want the real dirt on the principles involved (Daniel Bernoulli to get very particular). For the purposes of the at-home restorer, work primarily with the notion that dirt and lint is bad, as is overtightening, undertightening or in general mis-assembling anything. The little rubber syring used to clean out the noses of little tykes is more than suitable to clean up the little bores of the carbs.

Also, if you check out the section 7-1 of the 108 manual again, you'll notice that it describes most of what I just said with lots more words and in greater detail. They call the primary, stage I. The secondary is stage II in their parlance.

-CTH
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Old 04-01-2001, 06:51 PM
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Oh, and now that the carbs aren't attached, if you do crank the motor a few times to be checking the compression or run on starting fluid, it's a perfect time to see if your fuel pump works and how good the resulting gasoline is. Have the fuel line dump into a metal can, NOT glass or plastic. Glass breaks and plastic tends to melt (unless you have a handy, EMPTY gas can.

The resulting gasoline should smell like relatively new gasoline.

-CTH
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Old 04-01-2001, 07:07 PM
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the gas...

CTH...

The gas PUMPS out of the fuel lines A-ok! There is NO issue there!! AND it smells and feels like good gas...
The bigger question is whether or not this gas is passing through these carbs, WHICH I believe it IS, since that OIL was LOADed down with gas....
Maybe it's a mixture problem??? I know, I'm just grabbing at (milkshake) straws again!

Should I try the ether test now, with the carbs OFF??

Should I try to put oil in the spark plug holes before I do a compression test or just do a "dry" compression test? Or both??

Has anyone ever had such a HARD time getting a car to START?!??!?! AND there are pretty good odds that when it does start, it's going to run terribly!!!!! *oof*

~Christy
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Old 04-01-2001, 10:52 PM
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Dry first on all cylinders, wet second. Be sure to write down all the numbers. Keep the battery well charged.

-CTH
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Old 04-02-2001, 04:31 PM
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the carbs...again..

Hi...

I've been re-studying my MB sevice manual...the section about the Zeniths...and I NOW have a new thought...What's with all these AIR DUCTS??? MAYBE mine ARE clogged???
That'd make a difference, right??

~Christy
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Old 04-03-2001, 01:24 PM
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rats

My office has had internet connection problems for the past two days. I'm now down the block at a friend's desk. The really long post I wrote to answer your question got eaten. Now, I'll have to write it all over again. And I was so eloquent and thoughtful in the response. Rats.

-CTH
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Old 04-03-2001, 02:15 PM
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Machinery.

To the ancients, there were 6 simple machines, inclined plane, wheel and axle, screw, lever, pulley, and wedge. To read more about simple machines, check out this site: http://library.thinkquest.org/J002079F/index.htm

We humans love to make machines. We have expanded on the simple ones throughout the ages. In the past 150 years, the range of machinery has grown at an amazing rate. In the past 50 years, it seems all we humans do is create new machinery.

A machine is succinctly defined as "something that does work". It is convenient to discuss a machine in terms of WHAT work it does and WHAT input it needed to do that work. HOW the machine does what it does is of secondary importance sometimes.

We can say with a straight face, that your car is a machine. It's inputs are gasoline, air, electricity (that charged battery) and the driver wiggling various controls. The "work" is its movement from place to place, it's exhaust, and the occasional transport or movement of stuff (like knocking over a mailbox).

We can also look at your car as a whole bunch of little machines. For instance, the steering, engine, transmission, brakes, etc. Each of these little machines are in turn made of smaller ones. Steering is a machine made from a wheel on an axle, a couple of lever arms and another pair of wheels on the pavement. The transmission is the single most complicated mechanism in a car, it's made of some pretty intricate machinery.

Your engine is also a complex machine, with a few little machines of its own. The carbs are a small pair of machines (and you wondered where I was going with all this!) that take in gasoline, air and the foot pedal control and output a MIXTURE of air and gasoline, ready for burning by the engine.

There are no shortage of simple machines used in constructing your carb (The linkages are examples of levers, wheels and axles). There is a critical, not-so-simple machine there too. The air ducts carry air pressure (or the lack of it; vacuum) through the carb. A change in pressure in one component affects another. These components are engineered so that the collection of them produces work. Most of the fluids in your car (air is a fluid, sort of) are there to do "work".

Carbs can be complicated or simple. There are lots of folk that think the computerized carbs of the 80s are "very complex". Well, they're wrong. Those carbs are mindlessly simple, because all the complex duct work from earlier carbs are missing. The control work done by the ducts are simply done by the computer that they just don't understand. The reality, is that they didn't understand what any of the ducts did either.

All you need to know about the ducts (really), is that they should be clean, sealed where appropriate and open where appropriate. You can't reuse an old gasket because it won't properly seal a duct. You clean the carb with powerful solvents to clean out the gunk that seals up the ducts. The jets are handled with care (you don't poke anything in the holes) because they are critical to the correct functioning of the ducts.

Having said that, the more you know about the ducts, including why they do what they do and how they do it, the better off you are. If nothing else, you can have an interesting conversation with your dentist about his drills, once you've gotten some idea of the principles behind fluid as a machine.

-CTH

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