Pulled the Cam/Valvetrain: Results
Melting Slicks
Joined: Feb 2003
Posts: 3,053
Likes: 4
St. Jude Donor '03,'11
Originally Posted by norvalwilhelm
It's not alot of BS crap. The cam is 180 degrees out of time .
On the first time the marks are at 6 and 12 and the first revolution of the crank they are at 12 and 12. How is there any other way to do it.
He's got 200 pounds of compression.
Melting Slicks
Joined: Jan 2004
Posts: 2,672
Likes: 1
From: New Cumberland PA
Originally Posted by norvalwilhelm
Jimbo you are right as before. The cam is 180 degrees out of time. 
If the crank is at 12 and the cam at either 6 or 12, then its correct. The only thing that could be 180* out of time is the distributor.
There is a huge difference between a cam being 180* out of time versus the distrubutor being 180* out of time.
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Originally Posted by turtlevette
I don't see how the cam can be 180 out. As long as the timing marks line up every other rotation of the crank its installed properly.
On the first time the marks are at 6 and 12 and the first revolution of the crank they are at 12 and 12. How is there any other way to do it.
He's got 200 pounds of compression.
On the first time the marks are at 6 and 12 and the first revolution of the crank they are at 12 and 12. How is there any other way to do it.
He's got 200 pounds of compression.
He has 200pounds of compression??
Have to rethink what I have be thinking.
You win this round turtlevette
Racer
Joined: Jan 2002
Posts: 293
Likes: 2
From: Warrensburg, MO
The cam is 180 out with the distributor if he's trying to fire #1 with the cam at 12 and the crank at 12 (like his posts indicate). Put a sprocket on an old cam and look at the lobe profile with the timing mark at 12. The exaust just closed. He'll still get compression, but firing after the exhaust stroke. All he needs to do is put the #1 plug wire where #6 is now, and move the rest of the wires in order.
Jimbo
Jimbo
Team Owner
Joined: Jul 2001
Posts: 61,415
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From: Here to make friends
St. Jude Donor '11, '16-'17
Originally Posted by mandm1200
That's almost impossible. For the cam to be 180* out of time, the crank would have to be 12 and the cam at 3 or 9.
If the crank is at 12 and the cam at either 6 or 12, then its correct. The only thing that could be 180* out of time is the distributor.
There is a huge difference between a cam being 180* out of time versus the distrubutor being 180* out of time.
If the crank is at 12 and the cam at either 6 or 12, then its correct. The only thing that could be 180* out of time is the distributor.
There is a huge difference between a cam being 180* out of time versus the distrubutor being 180* out of time.
It's impossible for the cam to be 180 degrees out of time, if it was installed with the mark at 6 or 12.
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Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
To drop a distributor in I slowly turn the motor over while watching the number one valves. I watch the exhuast open close, the intake open and close and then bring it to about 10 degrees before TDC. I already have the distributor housing marked where number one plug goes so I install the distributor body with the rotor pointing to #1 mark on the housing,
Instructor
Joined: Jul 2000
Posts: 173
Likes: 0
From: Pumpkin Center CA
I read in awe the knowledge shared in the Forum. I am also pleased to see two very fine contributors accept another's solution and own up to their occasional lapse. Thanks to all contributors who also force me to think these things through. I cannot possibly contribute more to this issue than has already been said, but I continue to learn and offer my respect to all.
Thread Starter
Melting Slicks
Joined: Apr 2000
Posts: 2,145
Likes: 1
From: Ft. Walton Beach, Fl USA
I have a question for you guys that say the cam is 180 degrees out. The question is: If the motor was running fine and I had a starter kick back (from too much initial timing) and it ran after that but got progressively worse until it wouldn't start again, how did the cam get 180 degrees out if the motor was running?
Also, when I took it apart and reinstalled it I put the #1 piston at TDC and installed the timing chain at 12 crank and 6 cam. Why would that make the cam 180 out?
I'm not being a smart aleck but ya'll are confusing me. I've taken my Vette motor apart several times and installed the timing chain in the same manner and it runs like a champ.
Also, when I took it apart and reinstalled it I put the #1 piston at TDC and installed the timing chain at 12 crank and 6 cam. Why would that make the cam 180 out?
I'm not being a smart aleck but ya'll are confusing me. I've taken my Vette motor apart several times and installed the timing chain in the same manner and it runs like a champ.
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Cam can't be 180deg out only the distributor, that can be any amount out depending on where it is pointing when you at 0 deg on the balancer.
The crank gear is keyed and the cam gear has a hole that fits over the peg on the end of the cam. Forget about this 12 and 6 or 12 and 12 BS. It can be either way, if it is 12 and 12 the next time the cam comes around it is 12 and 6. The important thing is, when it is 12 and 6 make sure the dots line up everything else will take care of itself, it can't be on the wrong stroke etc. because of the keyway on the crank and the peg on the cam make it so everything lines up.
The crank gear is keyed and the cam gear has a hole that fits over the peg on the end of the cam. Forget about this 12 and 6 or 12 and 12 BS. It can be either way, if it is 12 and 12 the next time the cam comes around it is 12 and 6. The important thing is, when it is 12 and 6 make sure the dots line up everything else will take care of itself, it can't be on the wrong stroke etc. because of the keyway on the crank and the peg on the cam make it so everything lines up.
Burning Brakes
Joined: Sep 2004
Posts: 1,167
Likes: 2
From: Ft.Worth Texas
Originally Posted by nastee383
........ but got progressively worse until it wouldn't start again, how did the cam get 180 degrees out if the motor was running?.
Originally Posted by nastee383
Also, when I took it apart and reinstalled it I put the #1 piston at TDC and installed the timing chain at 12 crank and 6 cam. Why would that make the cam 180 out?
Nas, we aren't being smart either. We just want to see it fixed. If all the things have been like you have said in the past month or so something is slipping. Something like a bad crank key or dist. gear on cam or dist. Is your cam one piece or is the gear a seperate piece pinned on it? Have you removed the roll pin holding the dist. gear on to verify it is not sheered? Remove the dist gear and pull the shaft out and closely inspect it on Both ends. Do you still have the screetch sound when you crank it?
Race Director
Joined: Feb 1999
Posts: 16,978
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From: In Dreams There Is Truth Ohio
Originally Posted by MotorHead
when it is 12 and 6 make sure the dots line up everything else will take care of itself,
Race Director
Joined: Apr 2000
Posts: 17,676
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Originally Posted by GDaina
And that's when you drop in the distributor with the rotor pointing to the #1 plug wire. Then and only then everything will take care of itself....
When I said everything will take care of itself I meant, when you line up the 2 dots the cam and crank will be in the proper positions. Because of the keyway in the crank and bolts and peg on the cam you can't mess it up, it is idiot proof.
Race Director
Joined: Feb 1999
Posts: 16,978
Likes: 7
From: In Dreams There Is Truth Ohio
Originally Posted by MotorHead
That's true but most of the time it is not done that way. Look at crate motors with no distributors, or when you get a motor back from a rebuild etc. Most of the time you will still need to find TDC on the compression stroke for #1 then stab the dist. and yes magically under the timing cover the dots will be lined up
Le Mans Master
Joined: Jan 2006
Posts: 8,319
Likes: 7
From: Wilmington DE, Drive it like you stole it, 68 327 4 speed coupe
try this
with that much advance, you need to make sure that as you set mechanical lash on the valve train you do it with the intake and exhaust valves both closed, which will be 8 degrees off from TDC. if you set the valve at TDC your valve train will not be set right in some cases the valves will be set on the rising slope of the cam in other the falling. the result is i beleive what yoou are seeing. ive seen this proble before though is different circumstances. and the engine wont fire.
tim
tim
Thread Starter
Melting Slicks
Joined: Apr 2000
Posts: 2,145
Likes: 1
From: Ft. Walton Beach, Fl USA
Hasn't been much to post. I do have a date with the engine dyno scheduled for Feb 4th. I'll find out something right off the bat...whether its gonna start or not. If it does, I guess it something in the ignition/starter circuit on the vehicle.