Advice Needed - Can't Start Rebuilt 273

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I wish you were closer....I'd grab a 12 pack and head over to your house.
I hate to be whipped by a piece of iron. LOL toolman
 
Update Friday afternoon.

Well, I have to quit and go to bed for the midnight shift, but I think I discovered something wrong with my valve adjustment - as some have already suggested. At TDC for #1 cylinder, there is some preload on the exhaust valve. As I understand it, that should NOT be the case, right?

I performed the valve adjustment twice, but maybe the procedure I used is incorrect for a Mopar engine. It is based on "opposite" cylinders so it made sense to me. I first adjusted with the intake manifold off so I could see the cam lobes. I used the procedure where you adjust #1 exhaust valve with #6 exhaust valve at full lift, Adjust #2 exh w/ #3 exh at full lift etc... Don't tell me that is only a Chebby procedure!!!

Like I said, it's been 35 years since I've done this :)
 
I know there is a certain procedure for that but I just spin the motor over until
the intake valve closes. You will be on the power stroke and both valves will be closed. The stock specs for valve adjustment are .013" for the intake and .021" for the exhaust. These should be set hot but should get you started and then you can readjust them after the engine warms up. These specs are for a 1966- HP273 with a solid lifter cam by the way. I got the info from a factory service manual. Good luck! toolmanmike
 
toolmanmike said:
I know there is a certain procedure for that but I just spin the motor over until
the intake valve closes. You will be on the power stroke and both valves will be closed. The stock specs for valve adjustment are .013" for the intake and .021" for the exhaust. These should be set hot but should get you started and then you can readjust them after the engine warms up. These specs are for a 1966- HP273 with a solid lifter cam by the way. I got the info from a factory service manual. Good luck! toolmanmike
Click to expand...

Thanks very much toolmanmike! I'll try it that way tomorrow. I just looked through my 68 FSM and found no procedure for adjustable valves. I guess they were all hydraulic lifters by then.
 
I do everything by hand. Start by pulling all the spark plugs out. Turn the engine clockwise only, tighten, on the crank bolt. Add about .002" to both gaps because it is cold. My guess for gaps are .016" for intake valves and .021" for exhaust valves. Some cams call for a .028" gap hot. Anyway, that means you need a .018" feeler guage for the Intake valves and a .023" feeler guage for the Exhaust valves. Turn the engine over by hand and adjust the valves while they are on the base circle of each lobe. As you move through the lobes go back and keep checking the gaps of the other valves that are on the base circle and tighten or loosen as necessary untill you are confident that they are all gapped correctly. I've found the charts are not the end all. When this is done, screw in a compression guage into #1 cylinder and turn clockwise untill you start getting pressure. A finger in the spark plug hole works too. Keep turning clockwise untill your damper is at 0 degrees. You should be at TDC on the compression cycle. Always check TDC on the timing marks is TDC of the Piston. Mixed dampers and front covers? I've seen them way off. Now pull the cap on the distributor. The rotor should be under #1 spark plug wire terminal. You have Compression. You have Fuel. And you have Spark. The engine should fire right up. Adjust timing. Do your cam break in. Then, I make the final adjustment with the 016" feeler guage for intake valves and .021" feeler guage for exhaust valves with the engine running. Can you say messy? Readjust after about 5,000 miles and you should be good for almost ever.
 
I had the same problem, once , with 180 out. I think that is solved.
To adjust the valves, for sure; just for starting:plugs out.
Pull the covers, get #1 correct, then turn the engine over with a socket. Put a short piece of wire (solid #12) in the hole; watch the intake valve- as it closes, and the wire stops coming up, spin the crank a little more- you are on base circle; adjust lash. Repeat for all.
Then start it, with towels on the rockers, and final adjust.
 
I had a similar case with low compression and the engine not wanting to start. I checked the valve timing and it was out, I had installed the timing chain using the wrong indexes and it was a few teeth off. You can check the valve timing without removing the timing cover. If you have a factory service manual, follow the directions for checking the valve timing. Even if it`s not the problem it`ll rule out that variable.
 
godfatherofchry said:
dam i could have sworn i mentioned something of this afect about valves being to tight??
Click to expand...

You certainly did :) Hopefully that is the final problem I have.

I was positive I adjusted the valves correctly by the method I chose, which I did. But I finally had to come to the realization that the METHOD was incorrect. I wasn't expecting that. Same with the distributor being 180 out. Again a lack of the CORRECT knowledge on my part. I did not know that the timing marks facing each other was #6 TDC instead of #1. All valuable experience I guess :)
 
Longgone said:
I had a similar case with low compression and the engine not wanting to start. I checked the valve timing and it was out, I had installed the timing chain using the wrong indexes and it was a few teeth off. You can check the valve timing without removing the timing cover. If you have a factory service manual, follow the directions for checking the valve timing. Even if it`s not the problem it`ll rule out that variable.
Click to expand...

Thanks, this is good to know! I have a 68 FSM. I'll see if it is in there. I am NOT looking forward to removing the timing cover should my valve adjustment not be the problem.
 
66fs said:
I do everything by hand. Start by pulling all the spark plugs out. Turn the engine clockwise only, tighten, on the crank bolt. Add about .002" to both gaps because it is cold. My guess for gaps are .016" for intake valves and .021" for exhaust valves. Some cams call for a .028" gap hot. Anyway, that means you need a .018" feeler guage for the Intake valves and a .023" feeler guage for the Exhaust valves. Turn the engine over by hand and adjust the valves while they are on the base circle of each lobe. As you move through the lobes go back and keep checking the gaps of the other valves that are on the base circle and tighten or loosen as necessary untill you are confident that they are all gapped correctly. I've found the charts are not the end all. When this is done, screw in a compression guage into #1 cylinder and turn clockwise untill you start getting pressure. A finger in the spark plug hole works too. Keep turning clockwise untill your damper is at 0 degrees. You should be at TDC on the compression cycle. Always check TDC on the timing marks is TDC of the Piston. Mixed dampers and front covers? I've seen them way off. Now pull the cap on the distributor. The rotor should be under #1 spark plug wire terminal. You have Compression. You have Fuel. And you have Spark. The engine should fire right up. Adjust timing. Do your cam break in. Then, I make the final adjustment with the 016" feeler guage for intake valves and .021" feeler guage for exhaust valves with the engine running. Can you say messy? Readjust after about 5,000 miles and you should be good for almost ever.
Click to expand...

Thanks for taking the time to explain this! I have never messed with adjustable rockers but I remember back in the day my dad doing valve adjusting with the engine running. I remember the mess :)
 
When you adjust your valves do as 66fs but instead of adding .002 to the cold tolerances you`ll want to subtract it.
 
I read what you did and this is {{{what you wrote.}}}AND WHATS WRONG

1)I pulled the left valve cover and found TDC for #1 by watching the intake valve just start to open. Then I backed up the crank a bit to get the timing mark right at zero.

2)At TDC for #1 cylinder, there is some preload on the exhaust valve. As I understand it, that should NOT be the case, right?

THE REASON YOU HAVE PRELOAD ON THE EXHAUST VALVE IS BECAUSE WHEN YOU WATCHED THE INTAKE VALVE OPEN AND THEN BACKED THE MOTOR UP TO WHAT YOU THOUGHT WAS TOP DEAD CENTER ,YOU ARE ACTUALLY IN BETWEEN THE INTAKE AND EXHAUST STROKE FOR THE ENGINE.
THINK ABOUT IT IN THE RIGHT ORDER FIRST

POWER \ EXHAUST \INTAKE\COMPRESSION

TOP DEAD CENTER IS AT THE BEGINING OF THE POWER STROKE AND THE MARK ON THE DAMPER ,WILL LINE UP ON YOUR TIMING TAB.,
BUT IT ALSO LINES UP ,ONE MORE TIME ,WHEN IN BETWEEN THE EXHAUST AND INTAKE STROKE.
(((THIS HAPPENS TWICE )))I THINK YOU BACKED IT UP TO WHAT YOU THOUGHT WAS TOP DEAD CENTER ,BUT ARE REALLY IN BETWEEN THE EXHAUST AND INTAKE STROKE.
THIS IS WHY YOU HAVE PRELOAD ON YOUR EXHAUST VALVE.

1)VALVES ARE CLOSED ON THE POWER STROKE
2)THE EXHAUST VALVE OPENS NEXT <<<< PRELOAD ON VALVE

:hello2:YOUR IN BETWEEN THE INTAKE AND EXHAUST STROKE

3)THE INTAKE VALVE OPENS
4)THE NEXT STROKE IS THE COMPRESSION STROKE {{ VALVES CLOSED}}

DO THE SAME THING YOU DID BEFORE BUT DONT BACK THE MOTOR UP , KEEP GOING 90 MORE DEGREES CLOCKWISE TILL TOP DEAD CENTER.

THEN CHECK THE DISTRIBUTOR AND MAKE SURE IT'S ON #1 ONE CYLINDER ON THE CAP.
PUT THE WIRES ON GOING CLOCKWISE [ 1-8-4-3-6-5-7-2-}

:thumrigh: DOUBLE CHECK THAT YOU DID THIS RIGHT (WHEN YOUR ALL DONE WITH THE WIRES AND DISTRIBUTOR )BY ROTATING THE ENGINE OVER BY HAND AND WATCHING THE EXHAUST VALVE \\\ IT WILL BE THE FIRST VALVE TO OPEN AFTER THE POWER STROKE
,AND SINCE THE WIRES WERE PUT ON RIGHT ,AND THE DISTRIBUTOR WAS INSTALLED CORRECTLY, IT SOULD FIRE UP.

GOOD LUCK:salute:
 
T67POWER said:
I read what you did and this is {{{what you wrote.}}}AND WHATS WRONG

1)I pulled the left valve cover and found TDC for #1 by watching the intake valve just start to open. Then I backed up the crank a bit to get the timing mark right at zero.

2)At TDC for #1 cylinder, there is some preload on the exhaust valve. As I understand it, that should NOT be the case, right?

THE REASON YOU HAVE PRELOAD ON THE EXHAUST VALVE IS BECAUSE WHEN YOU WATCHED THE INTAKE VALVE OPEN AND THEN BACKED THE MOTOR UP TO WHAT YOU THOUGHT WAS TOP DEAD CENTER ,YOU ARE ACTUALLY IN BETWEEN THE INTAKE AND EXHAUST STROKE FOR THE ENGINE.
THINK ABOUT IT IN THE RIGHT ORDER FIRST

POWER \ EXHAUST \INTAKE\COMPRESSION

TOP DEAD CENTER IS AT THE BEGINING OF THE POWER STROKE AND THE MARK ON THE DAMPER ,WILL LINE UP ON YOUR TIMING TAB.,
BUT IT ALSO LINES UP ,ONE MORE TIME ,WHEN IN BETWEEN THE EXHAUST AND INTAKE STROKE.
(((THIS HAPPENS TWICE )))I THINK YOU BACKED IT UP TO WHAT YOU THOUGHT WAS TOP DEAD CENTER ,BUT ARE REALLY IN BETWEEN THE EXHAUST AND INTAKE STROKE.
THIS IS WHY YOU HAVE PRELOAD ON YOUR EXHAUST VALVE.

1)VALVES ARE CLOSED ON THE POWER STROKE
2)THE EXHAUST VALVE OPENS NEXT <<<< PRELOAD ON VALVE

:hello2:YOUR IN BETWEEN THE INTAKE AND EXHAUST STROKE

3)THE INTAKE VALVE OPENS
4)THE NEXT STROKE IS THE COMPRESSION STROKE {{ VALVES CLOSED}}

DO THE SAME THING YOU DID BEFORE BUT DONT BACK THE MOTOR UP , KEEP GOING 90 MORE DEGREES CLOCKWISE TILL TOP DEAD CENTER.

THEN CHECK THE DISTRIBUTOR AND MAKE SURE IT'S ON #1 ONE CYLINDER ON THE CAP.
PUT THE WIRES ON GOING CLOCKWISE [ 1-8-4-3-6-5-7-2-}

:thumrigh: DOUBLE CHECK THAT YOU DID THIS RIGHT (WHEN YOUR ALL DONE WITH THE WIRES AND DISTRIBUTOR )BY ROTATING THE ENGINE OVER BY HAND AND WATCHING THE EXHAUST VALVE \\\ IT WILL BE THE FIRST VALVE TO OPEN AFTER THE POWER STROKE
,AND SINCE THE WIRES WERE PUT ON RIGHT ,AND THE DISTRIBUTOR WAS INSTALLED CORRECTLY, IT SOULD FIRE UP.

GOOD LUCK:salute:
Click to expand...

Thanks, I understand what you are saying. I am not really at TDC like I thought I was. I thought this was going to be an easy project, lol.

I may even have the wrong timing cover and damper as someone else suggested. I'd better stop assuming my timing mark is even relevant.
 
[When you adjust your valves do as 66fs but instead of adding .002 to the cold tolerances you`ll want to subtract it. ] No this is incorrect. As the engine heats up everything expands and your gaps shrink, even more on the exhaust valves. Also you can adjust the valves with the engine running by using a swivel socket on an extension if using stock 273 mechanical rockers. I've done it too many time to count. Some one suggested using wire in the spark plug hole to get close to TDC. Sounds like a fine idea if you don't have the right tools. Don't feel bad either. I have a scar under my chin from a breather cap after a crankcase explosion trying to get a 273 to start 180 degrees out.
 
ABodySickness said:
The gasoline is fresh and the 4 bbl carb is from a running 318. The 273 turns over nicely and occasionally tries to start. A couple times it started and ran for a second or two but did backfire through the carb or spit out raw gasoline.

I'm getting pretty frustrated. Any thoughts or tips from you experienced engine builders?

Thanks,
Bruce
Click to expand...

Don't want to steer you down a different path, but this happened to me and I offer it to you for consideration. Long story short, I had a rebuilt 2bbl carb for the Barracuda stored upside down in a box for months while I was rebuilding the engine. Then came time to start my new engine. After a few weeks of what you're going through, someone suggested the needle and seat could be stuck (you stated "spit out raw gasoline", mine did the same). Sure enough, I pulled the top off and it was stuck. Solved my problem!
 
66fs said:
[When you adjust your valves do as 66fs but instead of adding .002 to the cold tolerances you`ll want to subtract it. ] No this is incorrect. As the engine heats up everything expands and your gaps shrink, even more on the exhaust valves.

I apologize, 66fs is correct with your application, iron head/iron block. I haven`t worked with that combo and a solid cam for a while. The clearances are going to be different for every engine based a lot on block and head material. I find on my aluminum head 440 the hot/cold clearance varies about .007 so for example, if I want my exhaust lash at .019 hot, I set it at .012 cold. Probably the best way to set the lash would be to set it with .002 added to the factory specs (as 66fs said) and then run the engine until it`s hot (it`ll likely be noisy) and then measure again while the engine is still hot to see how close you are to the proper clearances. Here`s a link to a cam site to help you. http://www.cranecams.com/?show=faq&id=4
Click to expand...
 
SpeedThrills said:
Re-read this, too.
Click to expand...
That´s how I do it every time, never fails.

And when the piston is coming up at TDC, put a wire in the sparkplug hole, as the piston is at the top dead center check that the mark on the timingcover align with the mark on the damper. At this moment put the dist in with the rotor pointing at #1 cylinder sparkplug wire, (assuming that the mark on the timingcover align with the damper that is.)
Perform a maintenance on the carb too to check that everything is alright with it (needles, seats and floats)
Hope that all of these advices don´t make it worse, lol.
Just trying to help.
 
With all this cranking of the engine be sure you are not washing down the cyl bores. Best way to check is pull your dipstick and smell the oil. If it smells like fuel change your oil. Also, did you use an additive with your oil? are you using a fresh cam or the original?
 
I don't want to bring up the obvious, but he said that it ran for a minute. It wouldn't even fire if it was 180 out. I think he crossed plug wires somewhere. Just a thought. Good Luck
 
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