Advice Needed - Can't Start Rebuilt 273

[MoparGarage]

Wow! I have been following your post hoping the next thing you try get's it started. May-be that 360 would be the best bet. I'm like you, I hate to give up.
With all the checks and adjustments you've made it should start and run. Who knows, maybe the prev. owner picked up a cam at a swap meet and it was a marine cam that runs backward. Good luck! It sounds like you've covered all bases. toolmanmike

Yeah Toolman, I feel like I covered all the bases twice, lol. I was thinking maybe they put a hydraulic cam in it or something. I don't feel like it has been a total waste of time because I have learned a lot while doing this. But it has gotten to the point that any addition time would be like unnecessarily banging my head against the wall.

 

[pettybludart]

Sounds like a mystery motor!You tried your best,now go with the 360 and cruise!Ha!:cheers:

 

[harvenator]

Did you ever check for air leakage around the intake or carb base?

 

[MoparGarage]

Did you ever check for air leakage around the intake or carb base?

No, but I did change to a different carb with new gasket. That didn't change anything.

 

[Small Block]

Read it all....and if you are dead sure the plug wires ran to the correct hole and came from the correct location on the distributor...then i'm dissapointed that we haven't figured it out. TDC #1, Rotor bug points to #1. Place that wire there. Get the book and look at where the next one is and follow through. Had this issue myself on a 318.
Small Block

 

[bigdemo1]

Have you tried putting a small amount of oil (1 to 2 capfulls)down the carb?

 

[66dartgt]

My .02 - check the vibration damper timing mark against a positive stop on cylinder #1. verify it is correct.

I just about tore my hair out before finding this problem on my motor. Car would not start and acted almost the same as you described. Bottom line - never assume - check everything. Wished I would have, would have saved an immense amount of frustration and time.

 

[Longgone]

You`ve pulled the timing cover and the gears are on correctly? It`s easy to get them off a few teeth without even realizing that you`re using the wrong indexes. It wasn`t long ago when I was at a friends house visiting. He had his engine on the stand and mostly assembled. I looked at the timing chain and he had installed using the wrong indicators. I had done the same thing and the car was acting like yours. The crank gear is easy to position wrong because people want to use the large mark that appears on the hub of the gear just above the woodruff key and not the small mark that appears on the tooth of the gear. You might check yours to see if it is done this way. Here`s a couple pics of the mark I used and then the corrected marks.

 

[MoparGarage]

You`ve pulled the timing cover and the gears are on correctly? It`s easy to get them off a few teeth without even realizing that you`re using the wrong indexes. It wasn`t long ago when I was at a friends house visiting. He had his engine on the stand and mostly assembled. I looked at the timing chain and he had installed using the wrong indicators. I had done the same thing and the car was acting like yours. The crank gear is easy to position wrong because people want to use the large mark that appears on the hub of the gear just above the woodruff key and not the small mark that appears on the tooth of the gear. You might check yours to see if it is done this way. Here`s a couple pics of the mark I used and then the corrected marks.

I did not know there were two marks on the stock crank pulley. I don't have a double row like in your pictures, but if there is a second little mark on a gear tooth, then I have missed it. That would be the problem then, but all of the pictures I have seen used the bigger mark on the crank pulley.

 

[Babyblue66]

I think this was mentioned, but I'd make sure your crank balancer and timing cover are correct. I know the older ones had a different timing cover.
It sounds to me that the timing is off, it should start right up if all was correct.
My 273 popped off with about two crank revolutions after the rebuild. I was very, very thorough in making sure it had timing marks correct, spark, and fuel.
I wouldn't worry so much about the compression readings. The rings need to seat.

 

[MoparGarage]

I think this was mentioned, but I'd make sure your crank balancer and timing cover are correct. I know the older ones had a different timing cover.
It sounds to me that the timing is off, it should start right up if all was correct.
My 273 popped off with about two crank revolutions after the rebuild. I was very, very thorough in making sure it had timing marks correct, spark, and fuel.
I wouldn't worry so much about the compression readings. The rings need to seat.

Thanks. After all of the checking I have done in trying to diagnose this problem, I am certain that the cover and damper are correct. I was hoping for the quick start-up as well. There is just something strange going on here. It just does not want to run. I am going to look for a second timing mark on the crank gear as Longgone suggested, but it sure doesn't seem like the timing is off anymore.

 

[66fs]

Sorry to hear the latest. I have always been leary of some one else's "rebuilt" motors. I'm guessing, if you ever check it out, that the valves are not sealing or it has some goofy cam, poly? early hemi? or just plain bad. Best of luck, Dan

 

[MoparGarage]

Sorry to hear the latest. I have always been leary of some one else's "rebuilt" motors. I'm guessing, if you ever check it out, that the valves are not sealing or it has some goofy cam, poly? early hemi? or just plain bad. Best of luck, Dan

Thanks Dan. At this point I am content to never find out

 

[65Val]

I know I'm resurrecting a 4 year old thread, but I'm having these same problems starting my fresh '67 solid lifter 273 as well. It tries to start by backfiring through the carb and such. I have done the following...

-loosened all the valve lash to almost double the prescribed cold settings,
-new plugs, wires, cap, rotor, points, condenser,
-new dbl roller chain (timed properly w.marks...see pic below), new solid lifter 260*/.430/110* cam and lifters,
-also substituted Chrysler electronic ignition system with no change.

I have done all the things previously laid out in this thread, and I still can't get it to start and run.

I had a set of "302" casting heads redone locally, and am using them.

Anything else you guys can suggest I try to get this engine running?

Thanks in advance.
-

 

[66fs]

Are you sure you are firing on the compression stroke?

 

[67Dart273]

Are you sure you are firing on the compression stroke?

X2........How did you set the timing, exactly?

1----Even if you are absolutely ABsoLUTEly positive that you correctly installed the cam and distributor, things are possible.................

2-----You might have gotten a reverse rotation marine cam

3-----You might have a misground (rare) or mismarked cam drive, so check the cam timing independently of timing marks. You do this by checking at what rotational crank degrees the intake/ exhaust events occur. Even if you don't have a degree wheel/ timing tape or a degreed balancer, you can calculate degrees per inch around the balancer perimeter.

4-----Either by mismatched parts or "slipping" of the balancer, the timing marks may not be correct, so verify them with a piston stop


The FIRST thing I'd do is use a piston stop to be sure the timing marks are accurate, then go completely through distributor setup to be sure it is actually timed correctly.

http://www.forabodiesonly.com/mopar/showthread.php?p=1969786849

 

[65Val]

Are you sure you are firing on the compression stroke?

Pretty sure. I did the "Wire TDC" method described above and the rotor end is pointing @ #1 plug wire, and the 2 - #1 cylinder rockers are loose. I also pointed my timing light at the balancer and during cranking, #1 is flashing right at 0*.

Here's the cam card for the cam thats installed...

 

[67Dart273]

"wire tdc?" You mean poking a wire in the plug hole? This tells you exactly NOTHING.

Read through the link I posted above.

ASSUMING...................

the cam is ground correctly, installed correctly, and that the timing marks are correct, there are ...................

ONLY TWO ways to determine if you are on the compression stroke

1---If either/ both valve covers are off, bring the timing marks to TDC and look at the no1 or no6 rockers. If both no1 valves are closed, you are on the compression stroke. If both no6 valves are closed, you need to rotate one turn

2---You can bump the engine over while holding your finger in the no1 plug hole. As soon as you feel compression, watch the timing marks. As they come up towards TDC, that is the compression stroke.

 

[65Val]

"wire tdc?" You mean poking a wire in the plug hole? This tells you exactly NOTHING.

It tells you when the piston is at TDC. Several members stated in this thread they use this method.

ASSUMING...................

the cam is ground correctly

I would certainly hope so. Can't compare to anything now that its installed.

installed correctly

I posted a pic of the timing marks lined up. Is this not correctly installed?

and that the timing marks are correct

Again, I would hope so. Can't compare without pulling the front off the engine.

, there are ...................

ONLY TWO ways to determine if you are on the compression stroke

1---If either/ both valve covers are off, bring the timing marks to TDC and look at the no1 or no6 rockers. If both no1 valves are closed, you are on the compression stroke. If both no6 valves are closed, you need to rotate one turn

Yes both No.1 valves are closed Both rockers are loose. I said that above.

2---You can bump the engine over while holding your finger in the no1 plug hole. As soon as you feel compression, watch the timing marks. As they come up towards TDC, that is the compression stroke.

Done that. No.1 is on comp stroke. Again...said that above.

Just use the "Wire TDC" method to confirm damper marks. It works.

 

[67Dart273]

Correct cam-----No need to "hope", just check it. You have the cam card, and as I said, even if the balancer is not degreed, you can calculate degrees per inch around the perimeter of the balancer. You can verify cam opening/ closing events. Even the shop manual gives you this for a stocker to check for a slipped cam drive. You can even ESTIMATE, look at the cam card. Exhaust closes 8* ATDC. You can just look at the timing marks and guestimate that

Correct timing marks.------- No need to pull the balancer/ timing cover. Use a dammed piston stop. Forget this wire in the spark hole B.S.

You said you "did all this," so why won't it run?

If it's puking flame out the carb, either a valve(s) is stuck open, or is open at the wrong time, or the ignition timing is wrong.

 

[66fs]

"wire tdc?" You mean poking a wire in the plug hole? This tells you exactly NOTHING.

Read through the link I posted above.

ASSUMING...................

the cam is ground correctly, installed correctly, and that the timing marks are correct, there are ...................

ONLY TWO ways to determine if you are on the compression stroke

1---If either/ both valve covers are off, bring the timing marks to TDC and look at the no1 or no6 rockers. If both no1 valves are closed, you are on the compression stroke. If both no6 valves are closed, you need to rotate one turn

2---You can bump the engine over while holding your finger in the no1 plug hole. As soon as you feel compression, watch the timing marks. As they come up towards TDC, that is the compression stroke.

It sounds like you are on the compression stroke. Method 2 works well, and makes me think. Have you done a compession check yet? Cut the fuel to the carb and do a compression check on all the cylinders. You should also set the valves adjusted to spec plus .002 of an inch. Also Do Not use a valve lash chart and think you are done. Keep, turning the engine and checking the valve lash till you are satisfied that you have the lowest spot on the cam lobe at the correct lash. This thing should fire up, like right now with that small of a cam. I have seen cams ground on the wrong centers and timing set marks way off, and that was when parts were made in the USA. There are tolerances on every part you have in your engine. That is why some engines run real good and others just run.

 

[winstoninwisc]

loosen the valves up too i would do that first your hanging the valves open and its not going to pop if you were at 135 even but 90 your not closing it couldnt pop if it was timed right aar tony showed me that first when i was tryin to set my crane gold rockers
that was over the phone i had it real close just with his instuction enough to find my timing chain was worn out stretched after years of abuse like he said lube the **** outa every thing and dont turn backward to find tdc go around again i got done hit the key it fired right up i buttond it down and i could turn backward 1/4 to 3/8 thats alot of slopin the chain like some 1 suggested get those valves closed first turn by hand dont go bang make sure pluggs are out

 

[65Val]

66fs---I did a comp check. Here's the numbers...

#1 - 115 #2 - 145
#3 - 115 #4 - 135
#5 - 140 #6 - 145
#7 - 125 #8 - 135

All cylinders except #1 and #3 jump past 30lbs on the first pulse....it takes #1 and #3 about 3 pulses to get to 30lbs. Bear in mind, this is a brand new rebuilt engine, so that may affect the numbers.

winstoninwisc---the rockers are loose when that cylinder is at TDC...in fact they are probably double the correct lash setting at the moment. I don't think they're holding the valves open at all. Timing chain is brand-new dbl roller.


EDIT---Another thing I did was rotate the engine, by hand, so that each cylinder was at TDC according to the firing order and checked the respective rockers. They all check out being loose, intake and exhaust, so I believe the cam is ground correctly as all the comp strokes showed up at the correct time....not a reverse-ground or misground cam.

 

[KitCarlson]

It may not want to start with timing at 0, change it to 10 BTDC. Also recheck firing order, clock wise. Plug wires at #5 and #7 easily swapped.

 

[4spdragtop]

Hey Val, in your pic of the timing chain/gears, dot to dot is when #6 is on compression. One more full rotation of the crank would give you #1 compression.
Also I had big mixups with dads 273...my stupidity. We were going off the balancer and the marks were wrong on it for some reason. Use a piston stop, or your wire. rotate over till its at tdc. Mark the balancer, reverse the crank rotation, mark tdc AGAIN. You should have 2 seperate marks. Mark the middle of those marks, and that is TRUE TDC. We f'd around with it for sooool long, then did this TDC method(thanks to 67dart273) and it works aces! Your balancer might be off in the markings....good luck, keep us posted!