rebuild on 360 not firing up, need help

[FullSizeJeeper]

Hello folks, its time to get some help, I've been working on getting my 360 buildup going and have hit a wall. Dropped it in my 82 FSJ last weekend. It's a AMC 360, .040 over, summit 8600 cam, crane roller rockers, MSD ingnition and disributor, edlebock preformer intake, timing chain, ceramic headers, 650 carb, port and polished intake, +.10 pushrods to correct value geometery.

1) I was not getting spark at the coil when I dropped it in last weekend.
2) had the MSD box and coil tested at High Pro, the box was bad.
3) got a new digital ignition from Summit, put it in this morning.
a) I now have very good spark at the coil.
b) checked the spark at all eight plugs and strong spark at all 8.
c) pulled the #1 plug, set before TDC and had wife crank it, compression pushed my finger out of the hole.
d) I am positive the timing gear was intalled correctly
e) I am postive the distributor is installed correctly
4) I have moved the distributor through about 40 degrees and still not catching
5) I have gas to carb, can hear it squirt when pump the accelerator
6) choke is a manual (adjusted using a bike cable, spring loaded to hold in open position, unless closed manually) I've tried throughout the range from fully closed to fully open
7) I rebuilt the carb and set everything to stock level, have made no adjustments yet.

This thing is turning and trying to start but it just will not catch and run. Any suggestions would be greatly appreciated!

[jeep_man_401]

Is it firing at all? Would love to hear a sound clip...guy could help alot more...sounds like you covered everything. How long did you crank it before you found out the first box was bad? What kind of lube is on the cam? Could it have flattened a lobe or two by now? Are you positive it is getting gas? Have you "dripped alittle" down the carb yet and it fired?
How did you check the spark? What dissy are you using, are you sure that is good?

I did the following on mine.

After I degreed in the cam I put marks on the cover for 0 and 5 and 10. I used a dampener with 360 degree marks. I finished the assembly without turning the motor from #1 firing. I hooked up the MSD and timing computer and left the dissy out. I then tested the spark by turning the dissy with the key on to make positive I had spark. Mesh the gears and hook the wires up accordingly.

Is there fuel in the fuel bowls? is the fuel pump working? Are all the vacuum ports plugged? Make sure the 'EGR' ports on the carb plugged.

Anybody else??

[FullSizeJeeper]

Yes, it is firing, several times it ran for several seconds, just cannot sustain. I primed it very well, when I pulled distributor, dizzy was covered in fresh oil, so oil pump is working well. I only cranked it a couple of times, could tell it was not getting spark. This was a used cam and lifter set. Coated it well with summit prelube that came with Cam.

Have tried the dribble gas trick, thats when it caught and ran the longest. Have a electronic fuel pump and timing cover is blocked off. Can hear gas squirt in carb when the accel in pumped.

I'm going to do a compression check this morning, advice from another site suspects low compression due to values not seating completely/ rockers too tight. I was very careful not to let this happen, but this is my first engine with Adjustable rockers.

All vacuum lines are new and triple checked, firing order trible checked. Pulled oilplug this morning, magnetic type, no sign of metal, so I think the cam is okay.

I'll update after compression check.

[fifesjeep]

I had a similiar problem with my build... My problem was that I was running out of room to adjust my timing... Sounds like you covered that problem... Once my 360 fired I had to stay on the gas in-order for it to stay running... After the break-in... I drained the oil etc.. Fired it, ran it at 1000 rpms and slowly turned the distributor until the rpms maxed and then I backed it off a little... I shut it off... hooked a vaccum gauge and a timing lite and I was shocked that where the timing etc was set at... I can't recall the numbers but... I do remember saying "wow"... I did have a problem with my carb... my floats weren't letting the bowls maintain a constant to sustain the needs of the engine... A quick tweak and "Walla". Now I need a hotter spark in-order to get a full burn.
Make sure you didn't wash your cylinders...
You can check to see if the valves are leaking by with a hose or scope... for the exhaust valve listen to the while you rotate the engine... then check the intake with the same method.. you'll hear a "Hiss" through the carb/intake... and if you lost the seal of the rings listen to the oil fill tube...

[Goose]

My vote is also 1. Check the timing first.. If I had a dollar for everytime I have been absolutely positive I had that distributor spot on correct only to find out that "aliens had moved it in the night" I would be rich.
2. fuel delilvery.. if you "dribble" and it runs.. you have found the problem.. "Hearing it squirt" is not the same as seeing liquid come out of those nozzles.. trust me..

and I am not being a smartass when I say this.. don't overthink this.. that engine is simple if it's got gas and it's got fire.. and they happen at about the right time.. it will run.. Unless it has 0 compression it would run..if it had a flat lobe it would still run..maybe not well but none of those things will keep it from running.. Fuel and fire and timing.. and a coffee can will run

[FullSizeJeeper]

Got it figured out finally. I removed the charcol canister from the vaccuum setup when I rebuilt it. I followed some advice I recieved and hooked the gas tank vent lines to the PCV loop. This was not good advice, it was throwing off my vaccuum and messing with the carb in addition. Plugged that and whoomm! She fired and ran strong. Timed it at about 18% BTDC, seemed to really like it about there.

Any ideas what to do with the tank vent lines? I put a ball valve on the return line so I could open adnd release pressure if it vapor locked

PS - I did do compression check prior to this (on 7 of 8 cyl, the last one by the heater core is a SOB). I was at 115-120 psi on all. That sounded a little low to me, but that was on the cold engine. Will check again tomorrow after seat rings. Unless- see below.

Now I have another problem, see the new thread, no power from tranny!

[Goose]

well thats a fresh engine also.. it wioll come up as the rings seat. Also the return lines come off of the stock fuel filter.. (I use it as a pressure bypass for the holley electric fuel pump)

[ironman_gq]

I just took a piece of fuel line and looped it from one vent nipple over to the other. took about 6 inches of line to do and it won't leak like some other methods.