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rbbailey
01-18-2014, 04:44 PM
Swapping engines 2.25 to 2.25 in a '65 IIa.



Should there be any play at all in the main shaft coming from the gear box in the bell housing?
Moly grease -- how much moly in the grease is acceptable? Napa has a version, but it does not say any specifics about it?
Timing: If the new engine was running fine when it came out of the donor truck, is there any reason to go through a full timing set up, or should I plug in the distributor and adjust from there? ...if that makes any sense... for some reason, the concept of timing and why and how makes sense to me, but the actual mechanics of how to do it are not manifesting in my head the way most stuff does. I can usually picture things and get things figured out ahead of time, but it just isn't working for timing.... so sorry if I sound totaly ignorant, but I've been reading the green bible, hand books, haynes, pictures, online, etc... still can't get it.

o2batsea
01-18-2014, 05:41 PM
Timing: suck, squish, bang, blow; the four events in a four stroke engine.
The crankshaft has to rotate two times for each complete engine firing cycle of all four cylinders. Therefore you must find the right point in these two revolutions to set the timing. The engine times off the #1 cylinder. It must be at the point where it has gotten to the top of the compression stroke and not the exhaust stroke (the two events when the piston is up). You can tell when this happens in several ways, but the two easiest are by observing the valves, and by noting the escape of air from the spark plug hole. Either way the most important thing is to look at the timing marks and be sure that the TDC marks line up. Remember that you are timing the camshaft, not the crankshaft.

I Leak Oil
01-18-2014, 08:29 PM
Every transmission I've ever had out had a little play in the input shaft. A little bit is no worry.
Can't help you on the grease question.
If the motor ran fine before, just put it in, get it started and perhaps tune it a little. I assume you mean ignition timing. It's simple really. The distributor just sends the spark to the plug at the right time in the compression stroke. Advancing the timing (turning the distributor CW) fires the plug earlier. Retarding the timing (turning the distributor CCW) fires it later in the compression stroke.

rbbailey
01-18-2014, 08:51 PM
Thank you, both.

The type of timing adjustments you are speaking of is what I hope to do. But I guess I just keep getting conflicting info -- people keep asking if I've set the timing before I get the engine in. They say to just read the Green Bible. So, when I read the Green Bible it tells me to set the BTDC and lock this down and use this special tool and the light and -- I thought all that was for a rebuilt engine, or one worked on.

SafeAirOne
01-19-2014, 05:48 AM
People keep asking you if you've set the IGNITION timing BEFORE you've installed a known working engine? That's kinda like asking you if you've checked the air pressure in the tires before buying a used car. :confused:

As for static timing the ignition goes, the concept is that the coil will 'fire' a jolt to the spark plugs the instant that the breaker points in the distributor open, so by placing the #1 piston in the correct position using the timing marks on the crankshaft pulley, you can place a continuity tester or test lamp across the breaker points and rotate the distributor until the breaker points JUST 'break' the circuit. In doing so, you've just set the ignition timing to fire when the piston/crankshaft is in the exact right spot.

There are a few more details to getting the procedure done correctly, but that's the gist of it.

The problem with this procedure is that there are so many variables involved that the timing will be perfectly in sync with the book specs, but will likely be incorrect to meet ACTUAL conditions, or so I'm told by people who still use distributors and carburetors to make their Rover engines go.

mearstrae
01-19-2014, 07:18 AM
The NAPA grease should be fine for anything on a vehicle. The tube should have spec.s listed that can be looked up on the net, if it's that important to you. I suspect the actual spec.s will only confuse you further. Put the engine in, and then do a tune, it would be the easiest way. I always set the timing to the recommended degree and then fine tune with a vacuum gauge to highest consistant inches of mercury. This only works if there are no manifold leaks and the carb is set to proper idle and mixture.

'95 R.R.C. Lwb
'76 Series III Hybrid 109
'70 Rover 3500S

rbbailey
01-19-2014, 04:01 PM
So based on your response, I think I am not going crazy. I don't "get it" now, but your description is basically how I understand it.

What I'm going to do is get the engine in (did it last night) then I'm going to set the #1 to TDC for ignition, then I'm going to make sure the distributor is also set to #1, then on down the line in firing order. I think, if I'm reading things right, this should get the truck running. At this point I will turn the distributor fore or back to get it running smoothly, test for pinging at high RPM's, then leave it at that. If I have to take it to a shop after that, I really don't care.

Here's a question that may need to be answered before I do all this, or it might just be a point of curiosity: Does the arm in the distributor spin and hit each consecutive point directly from one to another exactly when the spark is needed for that piston -- meaning that the rotation is relatively slow when you stop to think about it? (Don't know if I phrased that well enough to get across what I mean.)

SafeAirOne
01-19-2014, 04:38 PM
Here's a question that may need to be answered before I do all this, or it might just be a point of curiosity: Does the arm in the distributor spin and hit each consecutive point directly from one to another exactly when the spark is needed for that piston -- meaning that the rotation is relatively slow when you stop to think about it? (Don't know if I phrased that well enough to get across what I mean.)

The rotor in the distributor rotates at half the speed of the crankshaft, so the rotor contact will point to the #1 spark plug wire contact ONCE for every TWO times the piston goes up and down.

rbbailey
01-19-2014, 06:42 PM
Cool, that's what I figured.

When I position the rotor to #1, do I put it right on, dead center?

JSBriggs
01-19-2014, 07:16 PM
That is where the green bible comes in. Off the top of my head i think its 6° BTDC (before top dead center) Be sure to set the gap on the points with a feeler gauge as well.

-Jeff

rbbailey
01-19-2014, 07:19 PM
OK, but where is 6 deg BTDC to be set unless I pull the front cover and adjust the timing chain? Which..... for other reasons, I've been trying to pull the starter dog off the main shaft for two days now, won't budge anyway, so even if I do have to get in to the timing chain, I can't.

SafeAirOne
01-19-2014, 07:23 PM
Just use the timing marks on the crank pulley and the timing indicator attached to the timing cover. In fact, just follow the book and you can't go wrong.

JSBriggs
01-19-2014, 09:45 PM
No, no, no.

There are 2 types of timing.

Mechanical timing, set at the factory with the chain. The is only messed with if you are replacing worn parts. Most likely you are fine.

The second type is the ignition timing. This is adjusted by rotating the distributor. This is the timing you adjust.

-Jeff

rbbailey
01-19-2014, 11:46 PM
JSBriggs, thanks for that confirmation.

SafeAirOne, in the ignition section of the bible it simply says to use a light to adjust the timing off the flywheel by rotating the distributor. Maybe I'm getting confused because I was reading the first chapter where it actually talks about lining up the drive shaft for the distributor, etc...

Now, before I attempt to actually do this job tomorrow -- how do I know when the RPM's are correct at idle in order to start adjusting timing? (No tachometer in truck.) At this stage, do I set idle at the carb? Once timing seems to be correct at low RPM's how do I test for higher RPM's? Is it assumed that it will be set all the way through the power curve?

SafeAirOne
01-20-2014, 09:32 AM
I guess the first question to ask is "how does the installed engine run RIGHT NOW?" There's no need to fix something that isn't broken.

You really should have a knowledge of how the ignition system works to understand what you are doing. Have a look at this. This shows how a points-type ignition system works:


https://www.youtube.com/watch?v=W94iksaQwUo

The only thing I might explain differently in the video is how the 20,000 volts is produced by the coil: There are 2 separate windings of wire inside the coil. When you energize the primary winding in the coil (the circuit from the ignition switch to the points or "Contact Breaker" in the vid) a magnetic field builds around both the primary winding and the secondary winding inside the coil. When the points (contact breakers) open, that magnetic field collapses. When the collapsing magnetic field passes by the secondary winding inside the coil, it produces a large amount of voltage in the secondary winding, just like an alternator or generator produces electricity by passing a coil of wire through a magnetic field. Anyhow, this high-voltage electricity is then sent out of the fat wire on the coil down to the center post of the distributor for "distribution" to the spark plugs.

I urge you to make an effort to understand this system--It'll vastly help you in answering the questions you ask.

I Leak Oil
01-20-2014, 10:52 AM
Get the mechanical part of it (removing front cover, adjusting chain etc.) out of your head. If the motor ran fine before it was removed you shouldn't have to touch any of that. You probably don't have to touch the ignition timing either if it ran fine. Install the motor, start it up and see how it runs now.

Take a look at the video Mark posted. It will go a long way in helping your understanding of the ignition system.

SafeAirOne
01-20-2014, 02:58 PM
The first 4 1/2 minutes of this video is another fundamental explanation of the ignition system. Disregard everything after the 5 minute mark:


http://www.youtube.com/watch?v=dIQ4IWSpMO0

Once you have an understanding of how this system works, it'll be easy for you to see how adjusting the ignition timing works. When you adjust the ignition timing, you are really just changing the position of the cam follower on the points in relation to the lobes on the distributor cam, causing the points open sooner (firing the spark plugs earlier in the combustion cycle) or open later (firing the spark plugs later in the combustion cycle).

rbbailey
01-21-2014, 12:36 AM
I watched that first video yesterday, so thanks, it was a good thought!

OK, I think the one thing you are getting at -- why change what isn't broke? And get the mechanical part of what to do under the front cover out of my head -- that simple statement pretty much clears up my confusion. I think maybe people thought that when I had said I was putting in a "new" engine, they thought, "Have you done the timing?" Which would make sense with a NEW engine. So I was looking up and getting advice on the whole process for an engine that has had internal work or a new cam or something put in.

This is just a simple engine swap. A working engine coming out of one car, going into another, but I'm using the ancillaries from the old engine.

As far as I understand it, I should stick with a working engine, assume it is timed right internally, tune the distributor to the working engine. NOT go back to square one and set the static timing, etc...

The videos and such give good details, but they also confirm that my previous research had given me the basics in understanding the theory of spark to the engine.

I'll have this thing running in four hours.... which is what I said about 8 hours of work ago. Keep running into little things that shouldn't take so long, but do. So I'll work on it an hour after work each day this week and get it running some time this week.

I Leak Oil
01-21-2014, 06:57 AM
Sounds like you're on the right track.
The joys of working on old vehicles! What should take an hour can sometimes turn into many hours of after work fun! Soak it all in, you'll be an expert on your truck before you know it!

jac04
01-21-2014, 07:09 AM
Moly grease -- how much moly in the grease is acceptable? Napa has a version, but it does not say any specifics about it?

I assume you are talking about the moly grease for the shaft splines. If so, you really want moly paste, NOT moly grease. I use Loctite Moly Paste #51048 for these splines - it is 65% moly. Don't over-apply the grease, a little goes a long way. I don't know your location, but I'd be happy to give you a blob of it. Otherwise, some motorcycle shops will have moly paste since it's commonly used on motorcycle driveshaft splines.

antichrist
01-21-2014, 09:32 AM
If the timing is right for the #1 cylinder the rest will be right, assuming the plug wires aren't crossed.
It's easier to get to TDC on compression before you install the engine. There's a mark on the flyhweel on the right side of the engine (as you face the flywheel). It's on the edge of the flywheel accessable beneath a cover plate.
With the distributor rotor pointing to #1 the mark on the flyhweel should be at the pointer. If it's not, rotate the crank 180 degrees.
Always rotate the crank in the direction of rotation as there is always a bit of slack in the timing chain.
If you don't know for a fact it was running before being taken out, you can make sure the distributor isn't in backwards by looking at the tappets to make sure they are both closed at TDC. You'll want the rocker cover off anyway to check valve clearance.