318 Magnum first fire...timing?

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Furyus67

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I attempted to fire the 318 magnum for the first time on yesterday. Had a few setbacks. When I finally got around to starting it, it was dark. After it didn't start I didn't fool around too much to troubleshoot or make adjustments, but here's how it went.

I primed the oil pump first. The guy that rebuilt the engine said he primed it previously but that was about 8 months ago so I figured I needed to. I spun the crank by hand until it read TDC and the rotor was pointed toward the number #1 cylinder.
IMG_1857_rotor.jpg


Then I removed the distributor.
IMG_1860 (2)_pumpdrivegear.jpg


I took a picture of how the oil pump drive gear was oriented prior to removal. I inserted the 5/16 hex rod and spun with the drill. I was reading just under 80 psi. I replaced the oil pump drive gear in the same orientation as it was prior to removal. Replaced the distributor with the rotor pointed in the same direction, towards #1 cylinder.

When I attempted to start the engine, I cranked it 4 times with no fire. On the 5th crank there was a LARGE backfire that sounded like a shotgun blast.

I think there may be one of two issues.
#1 I am using MSD wires and a flame thrower coil. The rubber boot on the coil wire does not go onto the flame thrower coil easily. It seems as though the outer housing is too thick for the rubber boot. So maybe the coil wire isn't' fully connecting and I'm not getting spark.
OR
#2 My rotor is off 180 degrees. In my quick research I have read that a large backfire can mean it is firing on the exhaust stroke rather than the compression stroke.

To fix the 180 degrees out issue, with the crank spun to TDC as done previously, would I lift up the distributor out to where the rotor spins freely, spin it 180 degrees and then drop the distributor back down?

BUT WAIT THERE's MORE.

I noticed my freeze plugs were leaking coolant. After the large backfire we started packing up for the night. As I'm cleaning all the tools up I checked under the car and saw a couple wet spots. Come to find out, my freeze plugs are leaking. Just a steady slow drip.
IMG_1302_freeze plug.jpg


Can anyone tell if that plug is seated correctly? Why would they be leaking already!?! Is there a fix for this with the engine in the car. I don't particularly want to run stop leak in a freshly rebuilt engine.

Needless to say, it was a frustrating day. Any advice is appreciated.

If you'd like the watch the video of the backfire I uploaded it. Get a laugh out of my Dad jumping out of his shoes.



Here's a picture of what we're workin with.
IMG_1864_enginebay.jpg
 
Correct me if I'm wrong here guys but if the engine is at TDC, the rotor pointing at #1 cylinder, shouldn't the slot in the distributer drive gear be parallel with the intake? It looks off in the pic.
 
I attempted to fire the 318 magnum for the first time on yesterday. Had a few setbacks. When I finally got around to starting it, it was dark. After it didn't start I didn't fool around too much to troubleshoot or make adjustments, but here's how it went.

I primed the oil pump first. The guy that rebuilt the engine said he primed it previously but that was about 8 months ago so I figured I needed to. I spun the crank by hand until it read TDC and the rotor was pointed toward the number #1 cylinder.
View attachment 1715718841

Then I removed the distributor.
View attachment 1715718842

I took a picture of how the oil pump drive gear was oriented prior to removal. I inserted the 5/16 hex rod and spun with the drill. I was reading just under 80 psi. I replaced the oil pump drive gear in the same orientation as it was prior to removal. Replaced the distributor with the rotor pointed in the same direction, towards #1 cylinder.

When I attempted to start the engine, I cranked it 4 times with no fire. On the 5th crank there was a LARGE backfire that sounded like a shotgun blast.

I think there may be one of two issues.
#1 I am using MSD wires and a flame thrower coil. The rubber boot on the coil wire does not go onto the flame thrower coil easily. It seems as though the outer housing is too thick for the rubber boot. So maybe the coil wire isn't' fully connecting and I'm not getting spark.
OR
#2 My rotor is off 180 degrees. In my quick research I have read that a large backfire can mean it is firing on the exhaust stroke rather than the compression stroke.

To fix the 180 degrees out issue, with the crank spun to TDC as done previously, would I lift up the distributor out to where the rotor spins freely, spin it 180 degrees and then drop the distributor back down?

BUT WAIT THERE's MORE.

I noticed my freeze plugs were leaking coolant. After the large backfire we started packing up for the night. As I'm cleaning all the tools up I checked under the car and saw a couple wet spots. Come to find out, my freeze plugs are leaking. Just a steady slow drip.
View attachment 1715718844

Can anyone tell if that plug is seated correctly? Why would they be leaking already!?! Is there a fix for this with the engine in the car. I don't particularly want to run stop leak in a freshly rebuilt engine.

Needless to say, it was a frustrating day. Any advice is appreciated.

If you'd like the watch the video of the backfire I uploaded it. Get a laugh out of my Dad jumping out of his shoes.



Here's a picture of what we're workin with.
View attachment 1715718845


Yep, pull the distributor and turn it 180 then drop it back in.
Also know that it is just too damn east to get plug wires 5 and 7 reversed. (Chk your firing order)

A person can put the engine on TDC but have it on the exhaust stroke instead of the intake stroke.
If for example you pull the #1 plug and and turn the motor over until blows a piece of paper towel out of the plug hole, then bring it up to TDC and you can be sure it’s on the compression stroke.

Your distributor drive gear is right the way it is in your pictures.
It really doesn’t matter where it is oriented anyway, as long as your distributor rotor is pointing at the #1 terminal on the cap with the engine at TDC on the compression stroke.
 
Correct me if I'm wrong here guys but if the engine is at TDC, the rotor pointing at #1 cylinder, shouldn't the slot in the distributer drive gear be parallel with the intake? It looks off in the pic.
Hopefully someone can answer this with a picture? Is it possible I need to go another tooth to clockwise?
 
Correct me if I'm wrong here guys but if the engine is at TDC, the rotor pointing at #1 cylinder, shouldn't the slot in the distributer drive gear be parallel with the intake? It looks off in the pic.

If it makes you feel better about the drive gear, here’s a pic of someone else’s that had the same question.
Distributor gear alignment question

94387C2B-5476-45FC-B795-9C6191D57876.jpeg
 
Oh, and lots of core plugs will stop leaking after a little run time. (Like by the time it’s actually timed and ready to drive.)
If it doesn’t stop put a 1/2 tube of Alumaseal in it and that will do it.
You can even drain and refill after the leaks stop if you like.
 
Oh, and lots of core plugs will stop leaking after a little run time. (Like by the time it’s actually timed and ready to drive.)
If it doesn’t stop put a 1/2 tube of Alumaseal in it and that will do it.
You can even drain and refill after the leaks stop if you like.
Can't thank you enough. Really appreciate your help!!
 
As far as the freeze plugs, the one in the picture is not far enough in. Looks to be just level with the block, you should see the taper of the hole. You may be able to pound the plug in further maybe an 1/8 of an inch or so. If it still leaks...new plugs and I would use Permatex Aviation Sealant.
 
Those look like the good, deep brass freeze plugs, although they don't look seated all the way to the edge of the chamfer.

Agree they may need a heat cycle to set.
 
As far as the freeze plugs, the one in the picture is not far enough in. Looks to be just level with the block, you should see the taper of the hole. You may be able to pound the plug in further maybe an 1/8 of an inch or so. If it still leaks...new plugs and I would use Permatex Aviation Sealant.

He has the deep brass plugs so flush is fine and really common.
He also mentioned the motor is already in, which means a pain to get to.
For the super minimal issue he has, I would advise to not mess with them or things could get worse fast.

If the motor wasn’t in yet it might be worth doing, but my experience says they will stop leaking pretty quickly as is.
 
Where does he say this..
.
This is correct deep or shallow plugs.

You/I can see that they are the deep brass plugs with the wide shoulder so depth isn’t an issue like with the shallow shoulder plugs.
I agree that a little deeper is (book) correct but under his specific circumstances he’s fine like it is because of the wider shouldered plugs.
 
This recent thread of mine has some good information-
Distributor Install for first start. Double check my work!

The way you have it installed looks correct. I set my harmonic balancer to 10 BTDC on the #1 compression stroke, then installed intergear and distributor just like you have yours shown and it worked for me, instant start for break in. It sounds like youre probably at TDC of compression stroke on cylinder #6 (180 out). I would pull the intergear/distributor, prime it again (make sure you rotate the crank so that both heads get oiled), and reinstall the intergear/distributor as you have them, but make sure youre at TDC of compression stroke on #1 and your plug wires are oriented correctly. Easiest way for me to find TDC is to hold my thumb over the spark plug hole while turn the crank with a racthet. You will be able to hear/feel the pressure build in that cylinder. My intergear was clocked towards the drivers side front intake bolt like yours.
 
My 340 spit out a freeze plug right after break in. Put in another and happened again while driving. Used permatex when installing had it banged in flush. Finally I put a rubber expandable type in that one plug.
 
...and in all my years I've never had a properly seated deep brass plug need any sealant unless the hole was gouged.
 
The issue with not driving them in far enough is that it creates a ledge for crud to settle on and can cause premature corrosion of the bottom of the plug.

Much more of an issue with steel plugs, though.
 
Hopefully someone can answer this with a picture? Is it possible I need to go another tooth to clockwise?
It doesn't matter to the engine, where the drive is pointing; after you re-install the D,and re-synchronize the reluctor to the pole-piece, all that happens is the rotor moves to a new tower. So then you swap your wires over to the proper tower, and away it goes, same-old/same-old.
Where the rotor points to, at #1TDC compression only matters, when you end up with one too-short plug wire, or when it doesn't align with a cap that has a specifically numbered #1 tower. But any good mechanic will figure that out in a few seconds.
You can advance that drive gear to any tooth you want to, and you can still make it run no problem, and the timing lite won't know the difference. In the end, the only thing that changes is which tower becomes #1.
 
Definitely 180 degrees out of time. I had the exact same backfire 2 weeks ago on my first start. I was sure I had #1 on the compression stroke, but didn't actually test it with my thumb. Once I did that, pulled the cap and the rotor was pointing to the back, pulled it out and rotated it 180 degrees to point to #1 and she started up just fine.
 
In the video, it sounds like it's trying to start, so then the D is probably installed at least close to correct. When the D is out by 180*, the engine usually just winds up and sounds like the ignition is dead, with no fires whatsoever; because every plug is firing on the end of the exhaust stroke. I suppose it would be possible to have an afterfire in the exhaust with a big enough cam, but it has never happened to me.

It sounds to me, like the AFR is just not close enough. A cold engine wants a lotta fuel. Not to get the gas exactly, but to get the small droplet size that will support combustion; and this is also why the gas in the floatbowls needs to be fresh, because the fresh fuel contains the VOCs that aid in starting. Once the VOCs are gone, your gas is stale and becomes hard to light-off.
The big drops just puddle in the intake, or stick to the runner walls, like rain sticks to your windshield at speed. That fuel will get sucked into the chambers after the engine starts, and after the intake warms up a lil. Some of those gas molecules need to get up to close to 400* before they boil, whereas the lightest VOCs flash in the 90s..

At this point, your engine may be flooded.
When that happens, it often washes all the oil off the cylinder walls and you end up with poor cranking pressure.
So what I do is, on first start I mix the bowl fuel with 2-cycle fuel at about 5%.
But at this point, just to rule out flooded, I would pull the plugs, disable the Coil, and pump the gas out of the cylinders, and then put a squirt of oil in each hole, roll the engine over one turn, and inject another squirt, then walk away for 30 minutes.
When you get back, that oil will have, by capillary and creep, found it's way to the rings or cylinder walls etc. and you can pump the rest out. Yes it will make a mess, so prepare your engine bay.
Ok so pump it out with just a few revolutions, and re-install your plugs.
Then, assuming a flat-tappet cam;
Prove your timing is set to at least 15* advance.
Install the V-can hose.
Engage the choke in relation to your ambient temperature,
make sure the PCV system is installed correctly,
clamp the booster hose if you don't know it's history, and
start over.
As soon as it fires; get it up to 2200,and look for fuel leaks. Finding none; pull in all the timing she'll take, without regards to the actual numbers, until more timing does not produce more rpm. Then reset the Rs to, in the range of 2200 to 2500, and then take out a tiny bit of timing. Finally, let her alone for 20 minutes, watching for leaks.
By giving the engine all the timing she wants at 2200/2500, the required throttle opening will be less, so she will be burning less gas, making less heat, and keeping that heat in the top of the cylinder, thus helping to prevent overheating.
After the break-in, you will have to work out your timing ; do not leave the timing all pulled-in like I described. But before you change it, check it, because whatever it is, it will be close to what your engine will want, to cruise the hiway with, for best fuel-economy.
 
Correct me if I'm wrong here guys but if the engine is at TDC, the rotor pointing at #1 cylinder, shouldn't the slot in the distributer drive gear be parallel with the intake? It looks off in the pic.
img_1860-2-_pumpdrivegear-jpg.jpg

yes it does look off, but I know for a fact that the hold-down bolt is on the passenger side, soooooo, it looks odd but the white stuff is the intake. IDK about you, but that shadow-line made my brain work overtime, for a bit

the second pic looks better;
94387c2b-5476-45fc-b795-9c6191d57876-jpeg.jpg


and if this is at NO1- TDC- compression; it looks pretty good;
img_1857_rotor-jpg.jpg
 
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Some "notes" on timing and the guys above know this

1....Learn to set timing. SET it. SET it correctly
2....The drive slot is not all that important BECAUSE some distributors do not have the tang aligned at same angle as others. Nobody seems to know why
3...As mentioned earlier, dist can be "180 out" or 1/2 turn out This is EASY to prevent

HOW TO SET THE TIMING FIRST TIME EVERY TIME

1.....along the build use a piston stop or other means to make certain the balancer timing mark is accurate. The outer ring can "slip" in the rubber
2....After priming oil pump and when installing the dist intermediate shaft, you can "walk" it up out of the helix with a screwdriver if you need to change it. Set the timing marks to TDC and see where you are. Should (in theory) point to the left front intake bolt hole

There are TWO ways to get the no1 cylinder on the FIRING/ COMPRESSION stroke.

A....If you have the valve covers off, bring timing up to the mark and look at no1 and no6 valve pairs. One set will be closed, the other both somewhat open. Whichever pair is closed is on the firing stroke. You can set the dist into no6 instead of 1 if this is the case, otherwise, rotate crank 1 turn

B...The most common way is to remove no1 plug and stick your finger in the hole.. Bump/ crank engine until you feel compression, then watch for marks and bring them up NOT on TDC but rather WHERE IT IS THAT you want the intial timing, say, 8-10BTC with a dead stock cam, 10-15 BTC with a hot cam. Now drop the dist in with the rotor pointing at no1 tower hole and with the dist. body "plenty of swing room" for the vacuum can. This is where the "slot" issue will show up if you have an "oddball" drive tang. The fact is, it simply does not matter. Either use a different tower hole for no1 or else "walk" the gear so the dist will set how you want.

Next, rotate dist CW (retard for a SB) and if you have breaker points, rotate slowly back CCW (advanced) while using a light/ continuity device to detect "points just opened"
If breakerless, rotate slowly until reluctor tooth is centered in pickup core.

YOU CAN CHECK timing while cranking on the starter (thanks Crackedback)

Now it's a simple matter of priming carb. If it won't fire right away, stop and find out why, as you can easily wash down the cylinders and foul the plugs. If any question, check the cranking spark.

THERE IS NEVER a good reason when starting an engine such as this that you should have to crank and crank endlessly. Five seconds properly setup and primed it should at least cough and try to fire. If it "jerks" and "kicks" it is too far advanced. if it seems to fire but just plain wont run, suspect that it is RETARDED. (Check the timing on the starter) Make CERTAIN your priming fuel is FRESH
 
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One of the guys here used to say "The distributor can point to china"

The fact is you can close your eyes and throw the distributor gear in, and throw the distributor in right after it and it will run just fine. Simply find compression/ no1 and pick whatever cap tower which the rotor is pointing to, and it will run just fine.

I tell you this in an attempt to de-mistify all the fal-de-ral about the drive gear the rotor and all of this.

My first car was a 57 265 Chev. I used to do that and had a service station jock tell me "it could not run" after I'd just drove up. "The wires are all in the wrong place." Ran fine............well as fine as a worn out 57 265 2bbl can run...........
 
While all is true enough number 1 tower can be any place and indeed it will run, but now put on your custom purchased sparkplug wires and tell me how well they fit. lol
 
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