1974 D300 360 fresh rebuild will not start

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Do yourself a favor. Forget all the 'O'clock" references that are thoroughly mixing you up.
Prove your balancer TDC mark is TDC on #1 or #6 whichever is easier.
Then put #1 piston to TDC on it's compression stroke.
Remove the Passenger side valvecover, and
Go find Split overlap on #6 valves, as best as you can. Both valves should be similarly open.
If they are, then your cam-timing is close enough to run. And close enough to make satisfactory Leakdown numbers, and should post far better Compression test results

If your Compression Tester is reading 60psi on all cylinders, leaking into the CC, and split overlap is where it's supposed to be,
then ;
#1 install new Schroeder valves in the tool, the correct ones recommended by the manufacturer, which are NOT THE SAME as car or bicycle Schroeder valves; and
#2, repeat the test, cranking as many revolutions with a fully charged battery achieving about 300rpm or more; as it takes to get two consecutive same-psi numbers. This could take between 5 and 12 cycles. The fewer the better, but do not stop until you get two consecutive same or very near to the same numbers.
If you have previously poured gas into the intake, then you will have to either let it evaporate, or pour oil into the cylinders to wash it out. If you have oiled the cylinders, you will have to crank the engine long enough to distribute it , and pump the excess out. And yes, it will make a huge mess. The rings have to seal to the cylinders, and also to the ringlands.
As long as the rings are the correct diameter, the correct thickness, and not installed upside down, then the gaps of new rings, are not gonna be a big deal.
Like others have said; if 60psi is truly all that you have,
and the pressure by LeakDown test, is ALL going into the CC,
and split over lap is anywhere close to being correct,
then you got big trouble.
I would be pulling that hummer apart to see where I goofed.

PlantJesus said:
Adding air to #1 at TDC does not leak past valves, but does past rings. WHY!??!?
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Are you talking full compressor psi, often regulated to 120 or more psi? The answer to that is easy. It only takes milliseconds for that pressure to blow all the oil into the pan. Then the air is free to go where ever it wants, as fast as it able to.
At TDC in a worn bore, the gaps are opened up by .0031416 per .001 increase in bore size. The wear up there is often .020 or more, so the gap is increased from say .027 at the bottom of the bore to .090 at the top. And that is a superhiway for pressure loss. This is complicated by the new rings not sealing to the worn ringlands. And by the very real possibility of the cylinders, at the top of the bore, not being even close to round anymore. So there are at least 3 places the air could be scooting on by the rings.
 
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Just to sum up; your timing chain sprockets are incorrectly timed. Slide them off and install them with the crank sprocket pointed up [12 0'clock] and the CAM sprocket pointed down. Check with a straight edge using the center of the cam hole and the center of the crank [eyeball it]. The marks should line up. Assemble. Note the harmonic balancer timing mark. It should be on zero.

Cyl. #1 on compression stroke, dist. shaft gear slot pointed to left front intake manifold bolt, dist. rotor pointed to front of car [#1 spark plug]. Add oil and fire it.
 
Cam at 6 and crank at 12 will be timed on #6. (Easier to line up because the marks are close together) Turn 1 full revolution and it will be at 12 on the cam and 12 on the crank timed on #1.( Cam turns once to the cranks twice)

timing chain.jpg
 
George Jets said:
This is exactly correct. ^^^^^
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Line it up like you would a Chevy and turn the crank 1 revolution. Drop the distributor in with the rotor pointing towards #1 and you will be close enough to get it started. You can static time it to get it right on.
 
toolmanmike said:
Line it up like you would a Chevy and turn the crank 1 revolution. Drop the distributor in with the rotor pointing towards #1 and you will be close enough to get it started. You can static time it to get it right on.
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PlantJesus said:
Hi, everyone. First post here, long time lurker.

My 74 Dodge started making some horrible noises about 5 months ago, and I thought I had spun a rod bearing. Two weeks prior, replaced the flywheel and clutch, and installed a pilot bearing (there wasn't one???). After teardown.... Pretty sure what happened was I sheared an engine mount, and the other one was missing the nut to hold it in place :/ This thing sad for 13 years before I got it, it's been a work in progress. A year ago I fit an edelbrock intake and 4 barrel to it, which made a world of difference. During the tear down, I scrapped the old headers and went with a cheap pair of Hedmans.

So, engine already torn down, time to replace all relevant parts. All bearings, (pistons looked fine) new rings, lapped the valves by hand, did minimal 'porting' (removed the worst of the casting blemishes). Assembled engine, cam indicator at 6, crank at 12, 1st cylinder TDC. Spent 100 hours hunting down electric gremlins, wasted S*&t tons of money replacing the ICU, ICU plug, ballast resistor, dist, etc.... :/ Completely bypassed my wirewall connections and wired to a brand new ignition. Got my cranking voltage to at least 10 (from like, 6). Spark indicator shows voltage to the plugs, but.... I'm only showing 60 PSI compression when cranking.

Beat my head around, realized my leakdown test was lying; I had a one way check valve in the hose I was using... So, realizing my stupidity and doing it again properly... it blows air out of the other three cylinders on that bank. Realize my more stupidity; I used RTV on the head gaskets. Minimally, but.... F me. Take it apart, scrape, clean, new gaskets. TDC, timing on point... 60 PSI cranking. I was a mechanical engineer dropout long ago, and fancy thinking I understand what's going on, but this has me completely tossed.

Adding air to #1 at TDC does not leak past valves, but does past rings. WHY!??!? I'm seriously at the end of my abilities here, it seems. Any wisdom, whomever helps solve this, will become my new messiah.
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I would start simple. Confirm your compression with another gauge before taking things apart. Next I would check the balancer zero mark v/s true top dead center. Pull the distributor cap and confirm the rotor end is under the #1 plug wire.
 
Hey everyone, thanks for all the useful tips and pointing me in the right direction. I haven't gotten a chance to tear her apart yet, I run a small business and I've been running around like a chicken with my head cut off.

When I checked the cylinders for leakdown I used a metered air source from my air compressor (which I also used to confirm that my gauge is right, unless they're both wrong and reading the same thing.... :/ -that would be my luck, seriously)

I'll get to work taking off the accessories so I can get to the timing cover, take some pictures and keep ya posted! Thanks again!
 
Here's how I would do it, on an engine not bored ;
I Line the dots up; pinch the chain so they can't move, then slide them onto the stumps any old way. With the crank-sprocket engaged with the key,I just turn the cam until the cam-sprocket slides onto the key.
Once the marks are indexed right; it does not matter where the crank is nor where the cam is, as long as the sprockets slide on to the keys and I have NOT allowed the chain to decouple from the sprockets.

After the front cover is on, I can set the damper on the timing tab "TDC" mark, which can only occur with two pistons at TDC; namely 1 and 6. I determine which one is on TDC-compression and stab the distributor in accordingly.
Immediately, if I have not degreed the cam, I check that split-overlap is in the ballpark.
Com'on this is not heart surgery.
Next I bolt the heads on and, and immediately, before the valve gear is installed,I do a LeakDown test. I do it with the pistons on the bottom. This has the additional advantage of proving that the cylinders are not cracked, and since at the bottom is the best chance to have round cylinders, I should get the best readings.
Under the ridge at TDC, is gonna make the worst readings; unfortunately, under the ridge is also where it is most important to capture as much pressure as possible on the compression stroke, cuz the fire has already been lit when the piston gets there, and the pressure is rapidly building towards many times atmospheric.
After the Valve gear is on I do a second LD test, to see how bad the tops of the cylinders are.
If a bunch of it scoots past the rings at or near TDC-Compression,
I got a sick sick engine.
 
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Welllll there ya have it, folks. #1 at TDC with the spark rotor pointing towards #1 spark plug, those dots do NOT look like where they should be.... :wtf::thankyou:
 
Re this photo:

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IF the dots are actually lined up that is EXACTLY where they will be for no 1 to fire. But the rotor is COMPLETELY OUT OF THE PICTURE because the dist gear can be "anywhere" and therefore the rotor.

You align the cam timing FIRST and THEN perform ignition timing.

As said ^^ You rotate the crank 1 turn they will likely line up. With the crank mark at 12 and the cam at 6 o'clock NO 6 cylinder is ready to fire. It is done this way because the marks are easier to line up "dot to dot"
 
Yes, assuming that the gearset and cam keyways are machined properly. Degreeing the cam would confirm this.
 
toolmanmike said:
Cam at 6 and crank at 12 will be timed on #6. (Easier to line up because the marks are close together) Turn 1 full revolution and it will be at 12 on the cam and 12 on the crank timed on #1.( Cam turns once to the cranks twice)

View attachment 1715583947
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So... I guess I am confused by this, since it contradicts my manual, seemingly. With it lined up in this position, your photo, and mine, my number 6 cylinder TDC combustion?

*edit* Turned crankshaft 360, cam dot is now facing 12 o clock, as expected... Number 1 is at TDC with valves closed, number 6 is TDC valves open, Rotor is pointing towards where my #1 wire is....
 
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PlantJesus said:
View attachment 1715586932 View attachment 1715586933

Welllll there ya have it, folks. #1 at TDC with the spark rotor pointing towards #1 spark plug, those dots do NOT look like where they should be.... :wtf::thankyou:
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That would account for the spark timing to be 180 degrees out but would not account for low compression, is there another dot on the back side of your cam gear? I'm not sure if they can even be installed backward but the timing dot on an OE gear is up on the tooth ring.
 
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PlantJesus said:
So... I guess I am confused by this, since it contradicts my manual, seemingly. With it lined up in this position, your photo, and mine, my number 6 cylinder TDC combustion?

*edit* Turned crankshaft 360, cam dot is now facing 12 o clock, as expected... Number 1 is at TDC with valves closed, number 6 is TDC valves open, Rotor is pointing towards where my #1 wire is....
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That is right. Ur good there. Kim
 
Northern Grit said:
That would account for the spark timing to be 180 degrees out but would not account for low compression, is there another dot on the back side of your cam gear? I'm not sure if they can even be installed backward but the timing dot on an OE gear is up on the tooth ring.
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That picture isn't quite big enough to see, but I think they were off by a tooth, as well :/
 
Cam really should be degreed in.
I have seen it 4 separate times where the dot on the upper gear was on the wrong tooth(cam was retarded a tooth as a result in each case).
If you still have the old gear you could compare the two.

The 60psi cranking pressure is still the problem that needs to be solved.

As was mentioned, verify with another gauge.
Tested with all plugs removed, carb at wot, battery charger hooked up, test 4 pumps, and then again at 8 pumps.

If you are positive the gauge readings are correct, and are still only 60psi, then the cam timing really needs to be verified(degreed).

If the cam timing ends up being correct....... then I’d say it might need to come back apart.

That would be a situation I have never seen.........a re-ringed short block that has such bad ring seal it will only crank 60psi.
 
Poor PlantJesus is really confused now with all these different pictures and theories from everyone.

This does not have to be this hard, lets start over with the basic cam timing. This is the correct way to time it so that it will fire on #1 pictured below like you have it.

Cam at 12 O'clock
Crank at 12 O'clock
#1 up on compression stroke TDC

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Now that it is properly in time, you drop in your distributor here so that the rotor points to the #1 spark plug wire and lock it down.

OK Cam timed, and distributor is timed. Now to deal with low compression.

Always want to have the choke pinned open and throttle plates open when doing your compression check so it can get the proper air into the cylinders for the test.

Pull coil wire out of distributor and ground it so the car will not start during compression test.

More on low commpression causes, on the next post if compression test yields low.

,
 
George Jets said:
Poor PlantJesus is really confused now with all these different pictures and theories from everyone.

Now that it is properly in time, you drop in your distributor here so that the rotor points to the #1 spark plug wire and lock it down.

OK Cam timed, and distributor is timed. Now to deal with low compression.

Always want to have the choke pinned open and throttle plates open when doing your compression check so it can get the proper air into the cylinders for the test.

Pull coil wire out of distributor and ground it so the car will not start during compression test.

More on low commpression causes, on the next post if compression test yields low.

,
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You got that right!!! :p I do really appreciate everything, from everyone. Even when it's confusing. As a knowledge seeking mind, I like seeing the different ways people solve the problem presented.

I'm now confident I have the timing right... My choke is just disabled at this point; since I put the edelbrock intake and 4 barrel on it, (pre rebuild) I haven't had to choke it even when it's down to 15F. I'll make sure to open the throttle plates tho on the next compression test.

Got waylaid sealing together the poly for a water feature, and then... There's never enough to deal with at once :p ... My parents, while traveling to North Carolina to visit my new nephew got their fifth wheel (permanent home) broken into and robbed while getting serviced a few hours ago.

I'll try and finish up cleaning the gasket surfaces tomorrow after work, in between sending this months bills to clients :/
 
George Jets said:
Poor PlantJesus is really confused now with all these different pictures and theories from everyone.

This does not have to be this hard, lets start over with the basic cam timing. This is the correct way to time it so that it will fire on #1 pictured below like you have it.,
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Well I don't agree. The simple fact is it is MUCH easier to see if the dots are aligned when doing it by the book....AKA dot at 12 on the crank, 6 on the cam.

People need to LEARN this stuff. I first learned how to get no1 on compression sometime in the early 70's, "use your finger" or look at the valves. Or for Chris' sake, just time the God Damned thing on no6 how hard can it be.

Further, throwing the dist in as you describe DOES NOT set the ignition timing accurately.

By the way 'Chivvies" work the same way in regards to cam marks.
 
Well I don't agree. The simple fact is it is MUCH easier to see if the dots are aligned when doing it by the book....AKA dot at 12 on the crank, 6 on the cam.
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Just line up the dots as per normal...... rotate the crank one turn....... install distributor for number one.
Easy peasy.

However, I just use the “finger” method myself.

None of this will address the 60psi cranking pressure though.
 
PRH said:
Just line up the dots as per normal...... rotate the crank one turn....... install distributor for number one.
Easy peasy.

However, I just use the “finger” method myself.

None of this will address the 60psi cranking pressure though.
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PRH, let's let him do another compression test now that he has it in time.

Guessing he did not have the throttle plates open on the carb to allow the proper amount of air to enter the cylinders.

Makes a big difference having the carb butterflies open. Have done this myself, poor compression reading across the board with the throttle plates closed.

Think this is his next step, to open the throttle plates and compression test again.

Could be ficticous low compression by doing his test wrong. Hope so, then he can fire it up with some thin 5w30 engine oil and zinc additive.

Now he can start "Breaking In" those new rings on those smooth non-honed cylinder walls. Needs to get it up to temp and run it good for 2 to 3 hours , to set the new rings to the cylinder bores.

@toolmanmike
As you were talking about them building the engine without glaze braking or light honing the cylinder walls.

That was a poor recommendation by his machinist, especially with the new rings going into those used bores.

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