OldIHC

Ok, installing new spark plug wires. I know the firing order. Know it is CCW. The engine ran when I got it, but not so well and I only ran it a couple minutes just to move it around after it was taken off a flatbed trailer and that was it. The guy whom it was purchased from had told me he was not sure if the wires were right. Found 2 spark plug wires that had no rubber boots and were simply stuffed into the distributor cap holes.

I have the timing marks lined up at the crank pulley and engine pointer. Pulled No1 spark plug and inserted my compression tester. Turned the engine over by hand in order to line up the timing marks and watched the compression gauge needle. It never moved and I went around several full revolutions - so maybe too low a compression to show up on the gauge, hand cranking it is too slow, or the 30 year old gauge just ain't working no more?

In any case, have the timing marks lined up, but don't know if I'm on the compression or exhaust stroke. Most engine tune-up specs have a spark plug wiring diagram showing the cylinder number and the position of spark plug wires in the distributor cap. My service manual does not have any such diagram. As it stands now, my rotor appears to be lined up with the cap electrode at about the 4 o'clock position. As I recall, the old cap/wires had the No1 cylinder wire positioned at about the 2 o'clock position - but this may have been wrong based on the former owners tip that the wires might be wrong.

I know I can figure this out by seeing if the engine runs in one position based on my timing marks, and if not, rotate the engine around to bring the piston back up to TDC and reposition my wires on the distributor cap - trial and error method. Knowing where the No1 wire should be positioned on the distributor cap would just save me a little time.

Not ready to fire it up yet as I still have additional work to complete on the truck's electrical system to get it to the point where I can attempt to fire it up. So any suggestions as to where on the distributor cap No1 wire should be positioned?

Did you try the finger in the number one cylinder hole trick while you bump the starter? Add a little oil to the cylinder to see if you can raise compression?
Does your distributor have the tiny cap or the larger cap?
Maybe the lack of compression is the base reason for the no-start.
You've heard a million GOOD gas engines cranking...does this one SOUND like it has even compression on all cylinders or any compression at all?!?

So this takes two people but an easy way to tell if your on the compression stroke is to have someone hold the spark plug hole shut on number 1 with their thumb. Rotate the engine and when the thumb blows off the hole you are on the compression stroke. Line up the crank pulley and the engine pointer. Look at where your distributor rotor is and install number 1 spark plug wire there. Install the rest of the wires in the distributor following the rotation of the distributor and the firing order. 153624.

With #1 spark plug removed the intake vale should be closed on the compression stroke TDC. If the Intake is slightly open, exhaust stroke. The intake valve can be seen through the SP hole.

I did this on Thursday when I reinstalled the oil pump,

HTH

Were you timing the oil pump?

I had removed the oil pump and was reinstalling it. The OP gear is driven by the camshaft. The distributor is driven from an offset groove in the oil pump shaft. Once the pump is installed that groove SHOULD be positioned so that the distributor rotor is aligned with the #1 spark plug terminal in the distributor cap with the distributor installed.
(About "11 O'clock") So yes I guess I was timing the oil pump.

Marc

There is no number 1 spark plug position on the cap, there are six position any one of which can be used to fire any cyl. which cyl goes where is determined by how the dist is in relation to piston on compression. Place #1 on compression, somewhere around the timeing mark and look to see what tower on the cap the rotor is near, that is #1, then go from there.
If you want #1 to be in a specific position, then remove the oil pump and rotate until it places the dist rotor in that position.
The ign system fires 6 times in 2 revs of the crank, firing is evenly spaced, so it doesn't matter which is used to fire which, just that they fire in the correct order at the correct time.

If the oil pump hasn't been messed with the rotor should point about 11 o'clock like DOXIN posted,

but as CB posted it could be anywhere now since oil pump was R/R,

been messing with these GRD for 47 years, and most all were 11 o'clock for #1, unless muddled with,

Thanks all, GREAT INFO. Always learning here. Again, engine runs and did not smoke, just would not stay running (Zenith carb was in need of a complete rebuild and adjustment - which has been done by me, but not tested as of yet) and the engine had no power to it, but the carb was probably a big part of it and suspect a complete tune-up will improve things at this point. Going in stages here.

Monsonmotors - Never read of a "large/small" distributor caps used on these engine, but am definitely not an International engine guy (Yet, LOL). I used a new cap I bought at NAPA, #RR95 which looks like a small cap to me.

Well, my problem is it is just me working on the truck, no other hands to be had to help, so putting the thumb over the spark plug hole to "feel" for compression or cranking it over by myself is out. That was why I tried installing the compression tester I had. Yep, I am aware of adding a squirt of oil into the cylinder to aid in sealing worn rings - also a way to test ring condition using the dry/wet compression check.

I did watch a number of YouTube video's trying to pinpoint where the No1 wire plugged into on the cap. I did see several examples, but they were not consistent and was one of the things that prompted me to ask. The explanation provided by cornbinder89 makes sense and is great info. I do not know if the oil pump has ever been serviced in its lifetime. I did not know it could be "timed" with the distributor to position the No1 spark plug on the cap - which explains why I saw an assortment of No1 wire positions on the YouTube videos.

Thanks, DOXIN - I will try to look inside the No1 cylinder to see if I can spot the intake valve in relationship to the compression stroke. Sounds like a great idea and something that will work in doing myself. Did not think of that one. I may just go out and buy a digital inspection camera used to look inside an engine - its on my "to buy" tool list, so now I have an excuse and they are cheap enough (and I can get my brother to pay for it as it is his truck, LOL).

I think the above would be my best bet in getting the piston/timing mark exactly where it needs to be to fire. Then as cornbinder89 said, I can then use the position of the rotor to mark the No1 plug wire on my engine regardless of the oil pump if it has ever been R & R at some point in its lifetime. Odometer shows, as I recall, 44,000 miles on it which I am confident is original. bedrockjon - Where I have the No1 plug on the cap now, would be just about right if I moved it 180 degrees to the 11 o'clock position. However, I will get the engine itself in time and then use the rotor position to locate the No1 spark plug wire position on the distributor cap and go from there.

if it is 180 off you can pull distributor up a little rotate it to 11 o'clock, the tab/slot on the bottom to oil pump its not offset so it can go in either way,