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440 back together but runs bad...

John Tipps

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I just replaced my stock heads, cam/lifters and are using roller rockers and followed(I thought) all the instructions on the components, made sure several times the timing was set and plug wires were delivering to new plugs TF recommended and it runs awful, the timing must be at least 20* advance to run but its shaky and on the road there's no power (or any more than before) and it cuts out while pulling at 30 mph. I've tried moving the dist gear both ways and of course it just got worse-could it be the rockers/valves?
Heres what I did...
Installed new cam and chain, made sure dots were at 12 and 12 o'clock
Measured before and cut 440 source pushrods so rockers were hitting middle of valve stem,
Shimmed roller rockers for side to side clearance
Rotated engine to get 0 lash on each valve and then 1 turn on each then tightened
Finished assembly and did the 2000 rpm for 30 min ( it was running badly but the rpm,s were up so it wasn't noticeable)
Any help would be appreciated, this has become an expensive nightmare and it shouldn't be
 
Sounds like you have timing issue.. and may want to start from the beginning again and degree the camshaft this time.. check rotor phasing in the distributor too when you get there
 
I degreed the cam when I had the timing cover off,it was 1/2 degree off so I didnt mess w it-I agree I think its the timing but but ive checked it several times and its allways dead on and the rotors allways on #1
 
Text Book; Engine Compression Test -- for EFI, but still useful info.
A well-sealed cylinder should make 50% of its total compression in the first stroke -- use a remote starter button, record 1st, and 4th strokes.
The minimum spec for most gas engines is 100psi. If you're at 100psi, you have problems. Verify your gauge is correct, and the test is consistent -- ALL plugs removed, cylinders dry, battery charged.

1. Charge the battery if the battery is not fully charged.

2. X Disable the ignition system. X

3. X Disable the fuel injection system. X

4. Remove ALL spark plugs.

5. X Turn the ignition to the ON position. X

6. Depress the accelerator pedal to position the throttle plate wide open.

7. Start with the compression gage at zero and crank the engine through 4 compression strokes, 4 puffs.

8. Measure the compression for each cylinder. Record the readings.

9. If a cylinder has low compression, inject approximately 15 ml (1 tablespoon) of engine oil into the combustion chamber through the spark plug hole. Measure the compression again and record the reading.

10. The minimum compression in any 1 cylinder should not be less than 70 percent of the highest cylinder. No cylinder should read less than 690 kPa (100 psi). For example, if the highest pressure in any 1 cylinder is 1 035 kPa (150 psi), the lowest allowable pressure for any other cylinder would be 725 kPa (105 psi). (1 035 x 70% = 725) (150 x 70% = 105).

• Normal — Compression builds up quickly and evenly to the specified compression for each cylinder.

• Piston Rings Leaking — Compression is low on the first stroke. Compression builds up with the following strokes, but does not reach normal. Compression improves considerably when you add oil.

• Valves Leaking — Compression is low on the first stroke. Compression usually does not build up on the following strokes. Compression does not improve much when you add oil.

• If 2 adjacent cylinders have lower than normal compression, and injecting oil into the cylinders does not increase the compression, the cause may be a head gasket leaking between the cylinders.
 
Prob not a issue but I like 6 and 12 for the cam gear and crank.
Compression test and what's the plugs looking like ?
Measure for coil bind ?
 
Are you sure you have enough valve lash?
 
If you installed the cam at 12 and 12 your way off! Crank at 12 and the cam at 6 is what it should be. I hope that is what you meant. Also is this a hydraulic cam? If mechanical youre going to need some lash added

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Prob not a issue but I like 6 and 12 for the cam gear and crank.
Compression test and what's the plugs looking like ?
Measure for coil bind ?
If you installed the cam at 12 and 12 your way off! Crank at 12 and the cam at 6 is what it should be. I hope that is what you meant. Also is this a hydraulic cam? If mechanical youre going to need some lash added
When I removed th timing chain the previous builder had the dots on the cam and crank at the top of each, being a chevy guy in the past I forgot and put the dots together crank 12 oclock and cam at 6 and it didnt work,I called a guy and he said BB mopars are at 12 and 12 like it was when i removed it-is this not correct?
 
No it’s not correct, it should be at 6:00 and 12:00 as stated. Based on what you are saying your cam shaft is 180 degrees out.
 
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It wont matter the crank turns 2 revolutions to one of the cam. One time the crank is at 12 and the cam at 6, give it one turn and the crank is at 12 and the cam is at 12. Main thing is degreeing it. The poster did and it was only 1/2 a degree off. That tells the story.
 
The cam runs at half the speed as the crank. You're on either TDC #1 or TDC#6.
Turn the crank one full turn and marks are now 12 and 6.
 
Holy crap! Well there goes another weekend...is there a way to correct this without taking the front of the motor off?
 
You said it runs rough... have you checked the firing order? It’s easy to swap a couple wires and then may run poorly. Distributer turns counter clockwise and firing order is same as a Chevy 1-8-4-3-6-5-7-2. And what’s the timing at? Have checked with a light?
 
If it's hydraulic then you likely set the lash with the lifters compressed. Then when they pump up you are holding the valves open.
 
For # 1 firing TDC the chain has to be at 12 and 6 for the power stroke! Understand what post 11 says!
 
Don't tear your motor apart. Read posts 10 and 11. It makes no difference.
Im a little confused, so if all my timing "appears" to be correct to me and I have the gear dots wrong could I just pull the dist and turn the rotor 180 degrees?
 
Set your motor to #1 TDC then put the cam in at 12 and 6 period. You set #1 to TDC then put the chain on wrong. This makes #6 TDC power stroke.
 
Im a little confused, so if all my timing "appears" to be correct to me and I have the gear dots wrong could I just pull the dist and turn the rotor 180 degrees?
Does it start? If so your not out 180. If it’s out 180 I’ve never seen one run. They just fart and usually blow fire out the intake.
 
You said it runs rough... have you checked the firing order? It’s easy to swap a couple wires and then may run poorly. Distributer turns counter clockwise and firing order is same as a Chevy 1-8-4-3-6-5-7-2. And what’s the timing at? Have checked with a light?
Yes several times-its correct
 
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