How much preload?
06-19-2006, 03:51 PM
#1
TECH Veteran
Thread Starter
iTrader: (12)
Join Date: Dec 2004
Location: Rockville, MD
Posts: 4,354
Likes: 0
Received 0 Likes
on
0 Posts
How much preload? ok, PRC duals and Crane rockers. 1 1/4 turns is too much. im thinking maybe a 1/4 turn...half a turn max. what do you think?
06-19-2006, 04:21 PM
#4
Buy one for $20. Not worth guessing when it comes to your valvetrain.
Just saw your other post on not starting.
Definitely make sure what length pushrod you need. What do you have in there now for a pushrod?
If when you measure you find out you need a 7.325, PM me as I have a set here.
I was in the same boat a year ago, had too long a pushrod and car wouldn't turn over. Measured and bought the correct pushrod, all is well.
Just saw your other post on not starting.
Definitely make sure what length pushrod you need. What do you have in there now for a pushrod?
If when you measure you find out you need a 7.325, PM me as I have a set here.
I was in the same boat a year ago, had too long a pushrod and car wouldn't turn over. Measured and bought the correct pushrod, all is well.
06-19-2006, 04:27 PM
#5
You have stock heads, head gaskets and Crane rockers? Which rockers, 1.7 or 1.8? Why is 1-1/4 too much, that is right about where I would set them to get 0.080" of preload. Are you sure you got zero lash correct, that is where most people make the mistake with these rockers.
06-19-2006, 04:33 PM
#7
When you lifted the rocker, (this is going to sound queer 
) were you gentle? It is very easy to rotate the nut and actually preload the lifter with your fingers. I had this problem really bad when I did my Morel lifters, because the plungers would just go down and you couldn't even feel them. It took me a long time to get it setup right.
) were you gentle? It is very easy to rotate the nut and actually preload the lifter with your fingers. I had this problem really bad when I did my Morel lifters, because the plungers would just go down and you couldn't even feel them. It took me a long time to get it setup right. Trending Topics
06-19-2006, 04:33 PM
#8
TECH Veteran
Thread Starter
iTrader: (12)
Join Date: Dec 2004
Location: Rockville, MD
Posts: 4,354
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Viper
Buy one for $20. Not worth guessing when it comes to your valvetrain.
Just saw your other post on not starting.
Definitely make sure what length pushrod you need. What do you have in there now for a pushrod?
If when you measure you find out you need a 7.325, PM me as I have a set here.
I was in the same boat a year ago, had too long a pushrod and car wouldn't turn over. Measured and bought the correct pushrod, all is well.
Just saw your other post on not starting.
Definitely make sure what length pushrod you need. What do you have in there now for a pushrod?
If when you measure you find out you need a 7.325, PM me as I have a set here.
I was in the same boat a year ago, had too long a pushrod and car wouldn't turn over. Measured and bought the correct pushrod, all is well.
06-19-2006, 04:35 PM
#9
TECH Veteran
Thread Starter
iTrader: (12)
Join Date: Dec 2004
Location: Rockville, MD
Posts: 4,354
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by vettenuts
When you lifted the rocker, (this is going to sound queer ) were you gentle? It is very easy to rotate the nut and actually preload the lifter with your fingers. I had this problem really bad when I did my Morel lifters, because the plungers would just go down and you couldn't even feel them. It took me a long time to get it setup right.
) were you gentle? It is very easy to rotate the nut and actually preload the lifter with your fingers. I had this problem really bad when I did my Morel lifters, because the plungers would just go down and you couldn't even feel them. It took me a long time to get it setup right....it was never this hard with sbc;s...
06-19-2006, 04:36 PM
#10
Pushrods are fine, I think you just have an adjustment issue likely your zero lash setting. You can also use the old SBC method, but it takes more time. Its the way I had to do my Morels though.
Were these new lifters or ones already run and pumped up before you took the car apart?
Were these new lifters or ones already run and pumped up before you took the car apart?
06-19-2006, 05:16 PM
#12
TECH Veteran
Thread Starter
iTrader: (12)
Join Date: Dec 2004
Location: Rockville, MD
Posts: 4,354
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by vettenuts
Pushrods are fine, I think you just have an adjustment issue likely your zero lash setting. You can also use the old SBC method, but it takes more time. Its the way I had to do my Morels though.
Were these new lifters or ones already run and pumped up before you took the car apart?
Were these new lifters or ones already run and pumped up before you took the car apart?
06-19-2006, 06:40 PM
#16
TECH Veteran
Thread Starter
iTrader: (12)
Join Date: Dec 2004
Location: Rockville, MD
Posts: 4,354
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by vettenuts
Congrats 
What did you do?
What did you do?
oil pressure is about 25-30psi at idle all is well.
06-19-2006, 07:59 PM
#17
What's the cam, mine is pretty small and I was getting misfire errors as well. Need to shut off the idle and low speed misfire detection.
As for the adjustment, kind of hard to explain, but once you figure it out it is easy. Any problems loosening the adjusting nuts? How did you get them loose? My studs backed out when I tried to loosen mine, but I needed them out anyways so it wasn't and issue.
As for the adjustment, kind of hard to explain, but once you figure it out it is easy. Any problems loosening the adjusting nuts? How did you get them loose? My studs backed out when I tried to loosen mine, but I needed them out anyways so it wasn't and issue.
06-19-2006, 08:23 PM
#19
Launching!
iTrader: (1)
Join Date: Mar 2004
Location: Pennsville, NJ
Posts: 200
Likes: 0
Received 0 Likes
on
0 Posts
Each 1/4 turn of the Crane adjusting nut creates .015 of preload (I measured with a dial indicator). So your 1 1/4 turns should equal .075 of preload from zero lash.
