KitCarlson
Well-Known Member
Since the thrust is up front, cast would likely no longer drive oil pump nor distributor. Seems the twist in the steel would make the bearings tight, and squeel like a pig. But the key would shear before a twist.
Only runs 40 Degrees advanced
- Thread starter mr65cuda
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It's green.
67Dart273
Well-Known Member
LISTEN TO THIS GUY
Things you MUST DO (and have not) from the sounds of it..........
1....Check timing mark accuracy (TDC) with a piston stop
2....Check cam timing preferably with a degree wheel. IF YOU are using "dot to dot" be damn careful you aren't off a bit (easy with parallax) or that you have a multi key sprocket (they are not "gears") and that you are using the wrong marks
3....Bring engine up to the timing marks on compression stroke. There are only two ways that are practical. One is stick your finger in no 1 plug hole, bump the engine and feel for compression. Now wrench the engine that last part of a turn and put the timing marks WHERE YOU WANT THE TIMING that is about 15 BTC.
The second way is if you have either rocker cover off, rotate the engine until the marks on on TDC. Now determine if no1 or no6 valves are both closed. Whichever cylinder has both valves closed IS THE ONE which will fire. If no 6 rotate the engine 1 full turn so the marks are back up, and that will be no1 ready to fire
4...Now drop in the dist. Where the rotor points is not important, put the body of the dist so the vacuum can has rotational clearance from the manifold and firewall. Rotate the dist. body CW (retard). Slowly rotate back advance (CCW) until the points open or until the reluctor is in the middle of the pickup coil. YOU CAN CHECK TIMING ON THE STARTER with a timing light. "I'd go" for about 10-15* on a mild 340 type cam, more if a "hot" cam
With the timing marks "up" on the no1 compression stroke, plug the no 1 wire in wherever the rotor is "just coming to" going CW and feed in the rest of the wires
5....START IT UP
yellow rose
Overnight Sensation
The OP keeps saying he checked the dot to dot. I don't know if he doesn't know that doesn't mean **** or he is just stubborn, but for the infinite time every cam needs to be degreed. Period. If you can't do it, you have no business assembling an engine. Period.
I also explained how to check valve opening at crossover to see if it's even close on cam timing. Takes all of 2 minutes max.
If he didn't degree tha cam he needs to do it now.
was the compression test good ?if so cam is not twisted you would have different reading because of late valve opening events. run a leak down test on engine to check for slightly bent valves. I DID PULL A FERD ENGINE THAT HAD A MISS ON LAST 2 CYLINDERS THE CAM SNAPED BUT RAN JUST FINE.
67Dart273
Well-Known Member
I have never heard of a cam "twisting." Most cams are cast iron, and are brittle, and will simply crack and break. Only some exensive billet steel/ forged cam would twist, and if that happened, there WILL be other damage........stuck/ spun bearings, broken parts, valves, etc
Me either. This will be a first.
69_340_GTS
Well-Known Member
Besides, if it were somehow off 40° on even a couple cylinders, that engine would be running very rough no matter what you adjusted the ignition timing too. And from what I have read, it seems to run O.K.
67 gt
A boy who loves his Mopars !
All was needed was to remove the pump relay which is on the main harness as it won’t drive fuel into the unit and cause flooding every time you turn the key.
67 gt
A boy who loves his Mopars !
On your hand held what have you selected as in your ignition typehttps://documents.holley.com/199r11...vAtulklYm48CvHpNZ0IE9RwPmZJUmq0uyx8JaYkuJLY_E as you have been swapping to different distributors but are you changing your preferences on your hand held ? Page 38
KitCarlson
Well-Known Member
It runs ok, put it in gear, it dies.
Is the cam cast iron or cast steel?
Metal has memory. If you bend the crankshaft on your push mower when you hit a big rock you can hit the crankshaft with a big hammer back into place.
Why does it have to shear the cam key? The key is tightened to the gear and cam with a bolt.
Only in Deliverance do you have to squeal like a pig.
Not saying the cam is Twisted just saying there is a possibility.
KitCarlson
Well-Known Member
If the cam could be twisted, it may not stay perfectly straight, it would bind in the bearings, and squeal, as bearings tear up. A high pitched noise.
Key metal might be softer, bolted surface area may be limited. It is all theoretical.
I am stubborn, like to see cam stuff check ok, put that to rest. Then get to trouble shooting basic ignition problem.
IfItsGotWheels
XS Tech-Anything worth doing, is worth doing in XS
Just throwing this out there, but is it possible that when it locked up, that the cam key snapped and the cam gear spun on the cam??
67Dart273
Well-Known Member
I spose, but if the OP had degreed the cam this would have shown up in quick order. There are likely HUNDREDS of articles and videos on the www about degreeing a cam, and an inexpensive kit from Summit or others is somewhere around 80-100 bucks. Degree wheel, dial indicator, and some hardware doo dads
Entirely.
I would have thought he would have found that when he check the cam chain and put the chain tensioner on it.
And I "wouldda thought" he'd checked TDC "right off the bat".
When you were letting the Sniper control timing did you have distributor locked out and adjustable rotor that was set at 15 degrees on rotor? Did you change that back when you stopped Sniper from controlling timing?
67 gt
A boy who loves his Mopars !
He wasn’t using it to control timing.
IfItsGotWheels
XS Tech-Anything worth doing, is worth doing in XS
Not necessarily, unless he actually checks the key & slot, he might never notice. The dots on the gears would still line up, but the cam would be out however much the gear turned on the cam
There was a thread about a 5.7 hemi that did this very thing. I mentioned it on pg 1. If key or pin sheared chain /gears would still line up. Wouldnt know unless cam and crank gears are both checked.but if im not mistaken it was checked.
B'cuda
Well-Known Member
I would want to replace the components that were involved with the lock up, and in the chain of events that would include the cam and chain set.
On another note somewhere a cloyes set was mentioned. One with different key slots?
On another note somewhere a cloyes set was mentioned. One with different key slots?
KitCarlson
Well-Known Member
My posts about variable reluctance pickup polarity are not valid. I found that the dual sync, and hyperspark are both hall effect distributors. OP is not aware. I found on the Holley Sniper forum a question about difference between dual sync vs hyperspark distributors. Dual sync has cam type sensor too, an indicator for #1 sync for sequential efi and direct fire cop without rotor. Dual Sync vs HyperSpark
The OP started with dual sync, broke that, then purchased hyperspark. I think problem lies in step up, of distributor, wiring, phasing rotor. The link above suggests nobody knows....
The OP started with dual sync, broke that, then purchased hyperspark. I think problem lies in step up, of distributor, wiring, phasing rotor. The link above suggests nobody knows....
I thought that possible that’s why I pulled the timing cover and check the keyways and made sure it was still set up dot to dot like I put it in 4 years ago
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