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RH 454 crusader timing

"Okay from what I see on this

"Okay from what I see on this thread...

Since I have a Delco EST on my 454s, I would be better to not time as per the shop manual (idle timing with electronic advance disabled and 10 BTDC).

I would not want to use a timing light with a digital advance, but a real time light and timing tape decal applied to the harmonic balancer.

I would match the RPM and the correct marking on the tape with the spark plug advance curve graph from my shop manual. I would take the readings at every 500 RPM.

Would it be better to do the total timing with a load on the engine?

PS Anyone know the diameter of the harmonic balancer for the 1991 454CID?

PSS I think the job would much easyer with this as it must be reliable and has tach built in to make the total readings easyer...

http://buy1.snapon.com/catalog/item.asp?P65=&tool=all&item_ID=86056&group_ID=138 8&store=snapon-store&dir=catalog"
 
"Scott, get a feel for what so

"Scott, get a feel for what some of the other guys have to say on this as well.

I have no issue with the tachometer built into the light! This can be useful!

You will still take your ignition into BASE mode to set BASE. It's the TA that we want to concern ourselves with. That is the spark lead that can/may cause damage if incorrect!
It can/may also limit performance if incorrect!
If a BASE of 10* BTDC gives the correct TA, then all is good.

Yes, for me, I'd use the standard mode for checking TA and curve if so inclined!
Every 500 rpm would lend you a good reference.

Load or no load should give you the same results unless tied into a ECU/ECM that receives data that could effect this.

Best, IMO, to measure your balancer yourself. You will eliminate any error or unintentional misinformation this way.
The decal degree markings are very specific to diameter."
 
"I think 7" but could be 8

"I think 7" but could be 8"; like R said, measure to be sure...definitely NOT a 6" diameter.

Don't think you have a PCM, so all timing control is in the module and should be based solely on RPM.

You can set initial timing and verify full advance OR you can set full advance. If the module is working right, you should have same result either way.

With my TB-IV setup, I set it at full advance (no-load) and live with whatever the module provides as initial. With no startup issues, hot or cold, it isn't an issue."
 
Hello I'm updating you on

Hello I'm updating you on my stb. engine troubles or maybee port as well?? I took the carb and intake man. off to see the shape of cam and lifters to my suprise looked real clean and not much sign of where but I pulled to lifters out of #7 cylinder pushrod spots when fishing out 1" piece of pushrod with maganet and invertently pulling out two lifters as well. I finally put everything back together and it ran great however after runing it for a few minitues on plane I got it up into 4000 rpm and had quit a bit off vale chater probable didn't get them exactly set right even the second time around. The boat ran great for first halh hour then valves seem to chater a bit more and then less power and rpm. Do the rocker arm nuts go bad or losen asw they get older 1967 reminder and sould I repace tem with roler rocker arms while replacing nuts and ball?
 
"I would not change out the ro

"I would not change out the rockers for roller. Use new Dorman nuts, #693-022, if there is not good friction with your existing.
Your oil pressure was good at 4000 rpm?"
 
I would suggest you check the

I would suggest you check the oil to see if it has a gasoline odor and looks thin and/or the oil level on the dip stick shows high.

One time in my 22 year history with my 454s I had a diaphram break on the fuel pump and leaked gasoline in the engine. The valve tappets sung like a singer sewing machine.

Just a thought.

Chuck Hanson
 
"Dave my oil pressure gage was

"Dave my oil pressure gage was at about 50 psi.I'm not sure if I have the rocker arms set at the right tenssion. We set them while running made rattle by losening then slowly tightened until it stoppped rattle then a half turn to lock nut is this proper way of tightening. Its hard to tell if they will be tight enough when at higher rpms under more pressure.
Chuck after I put everything back togerther we changed oil cause water from intake man. The oil apeared to be a litte thing but lot of vales didn't work with rocker arms side ways. We ram out 10 miles and back yesterday and the oil still looks good, clean and thick."
 
Chuck I'll have to check a

Chuck I'll have to check again cause first time I changed oil It did smell a litte gas fumey. Thanks Rafe Sackett
 
""We set them while runnin

""We set them while running made rattle by losening then slowly tightened until it stoppped rattle then a half turn to lock nut is this proper way of tightening. "

I believe that to be an unusual way of setting hydraulic lifter lash. I know it is done with some other engines. Do this again, but with a cold, non-running engine. There are two crank positions required to do all 16. The rocker nuts should be loosened up before starting. Work on only the fully closed valves. While spinning the push rod with one hand, tighten the nut with the other, until you can't spin the rod, then another turn on the nut. A search may provide more detail on this, but basically that's it. Do 8, then spin the crank 360 and do the other 8. I don't have the intake/exh./cylinder #'s in front of me right now, but you should search to find that."
 
"Rollers work but aren't c

"Rollers work but aren't cheap. You have to change the valve covers or modify the stock ones to get clearance.

For setting the lifters while running, at idle, back off nut until 'clacking' starts, then tighten until clacking stops, then tighten 1/4 turn, let engine rpm stabilize, then tighten another 1/4 turn. (you can go to one full turn if desired.) Repeat for the rest.

If you want to adjust the rockers cold, set #1 to TDC, on the compression stroke. On a RH engine, adjust INTAKES: 1,3,4,8 and EXHAUSTS: 1,2,5,7, for zero lash, then tighten 1 full additional turn. Rotate crank one full revolution. adjust INTAKES: 2,5,6,7 and EXHAUSTS: 3,4,6,8.

The trick to doing the non-running adjustment is finding "zero lash". The running method is messier but subject to much less error."
 
"No offense, Mark, but IMO it

"No offense, Mark, but IMO it is best to use the 8 stop method for doing these statically.
Same basic procedure, but you do only two at a time, stopping the engine at 8 resting points!
You go right down the firing order once TDC # 1 C/S is achieved.
LH/RH engine makes no difference as long as correct rotation and firing order is used.
I find this to be more accurate, often causing no need to go back through them dynamically."
 
"No offense taken; I've no

"No offense taken; I've not had an issue doing these type of adjustments statically (eight at a given angle of rotation) or dynamically (one at a time).

from a statistical point of view, I'd be hard pressed to call that approach "best" without qualifiers. Accurate, high potential; many detailed steps with lots of room for error, yes.....I'd vote for the dynamic, one at a time method, especially if the background of the operator was unknown and someone else was cleaning up the oil that escaped the heads."
 
We tried the adjusting them th

We tried the adjusting them the running way twice and had it wose the second time lost power and top rpm. I had a couple of race care machanic friends tell me to do off cold by spinnig pushrod while tightening nut till arm stop spinning but how hard should I be turning push rod? Do turn it as hard as I can with fingers?
 
"This is the exact concern abo

"This is the exact concern about where human error occurs......

My perference is to back off the nut until the push rod spins freely between your thumb and forefinger. While spinning the rod, tighten the nut until you can feel increased drag on the rod. This is "zero lash". You should be able to press down on the rod (maybe via the rocker) at least 0.080" if the lifter has bled down...the additional turn is to center the plunger within the lifter's body.

You may want to invest in a vacuum gauge and a compression gauge and assess the current state of this engine once the valve adjustment is done. With that many hours, some wear is a given. You can waste a lot of time trying to tune up a 'tired' engine and not make any progress."
 
Oh so the pushrod can still sp

Oh so the pushrod can still spin but its at that piont where I can feel more drag on it that is "zero lash"? I was thinhing it wouldn't be easy to spin and probable would have over tightened.Thanks
 
"You only get to use your thum

"You only get to use your thumb and forefinger to spin the rod. It's really pretty obvious, once you do this once. A collapsed lifter will mess this up, however.
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And, these nuts are dented, and designed to provide quite a bit of friction. They need that friction to stay in place; if in doubt, replace with those Dorman nuts."
 
"What we are ultimately achiev

"What we are ultimately achieving is setting the depth of the hydraulically operated "plunger/piston" within the body of the cam follower (lifter).
That is ALL we are doing!
We are doing this so that rocker arm/valve takes best advantage of the hydraulic principle of the cam follower.
The average travel of this "plunger/piston" is anywhere from .080" to .100"+, depending on the follower manufacturer/engine manufacturer.

Do the math.... Rocker arm ratio X's thread pitch X's number of turns on the adjustment nut....... there is the amount that one rotation of the adjustment nut will cause a change to the plunger position within the cam follower!

Here's the kicker when doing this statically after an engine has been run:
The hydraulic chamber has now been filled with oil.
We will see little movement of plunger/piston..... it is now hydraulically locked, so to speak.

This is a good reason to set these before priming the oil system of a new or newly over-hauled engine. You can actually watch the plunger travel as you find ZERO lash. (intake manifold not yet installed!)

Mark, the reason behind the 8 stop method (for me anyway) is that this places the cams (per cylinder) at the ultimate location for this adjustment. While a given cylinder is at TDC C/S, the followers are at the lowest section of their respective cams!
The other method works, I simply believe this to be more accurate.
And there is also less margin for error..., IMOO here.

."
 
"This is a good reason to

"This is a good reason to set these before priming the oil system "

I was with you until this. Do you mean to type "set these AFTER priming?" seems like you want to have the lifter filled with oil to resist movement during the adjustment exercise to prevent setting too tite.
 
"But, you don't want plung

"But, you don't want plunger movement during the zero lash process, correct? If the plunger moved in(down) then the system could be too tight.

I had always thought you needed the lifter plunger fully expanded at the point of adjustment, then the one full turn of the nut depressed the plunger by so many thou. Without it being full of oil, only the light spring is keeping the plunger extended."
 
"Well Dave, I understand you,

"Well Dave, I understand you, and this needs qualifying, I suppose!
And yes... Mark is correct... that's what I'm suggesting.
Not only does it move more easily.... it moves! LOL (I. E., not resting on a hydraulic cushion)

3 ways this can be done: (and I'm sure possibly more)

New Engine/New followers: Using the 8 stop method. Intake not yet installed. Engine oil system not yet primed.
This allows you to view the plunger/piston as it freely moves within the follower body.... (it can not do this once primed)
This is very easy as you can see the inner plunger/piston as it begins to move down from it's top retainer clip.
Much much easier and more accurate, and avoids any confusion as you can see from the conversation in this thread!
Again this is IMOO here! You guys do what works best for you.

Existing engine/Pre-oil filled followers: Whether 8 stop method or not, the follower is hydraulically pumped up (so to speak) now!
Now the procedure is slightly different and we are back to feeling the rocker arm, or spinning push rods... of which I would not recommend. I'd rather work with the tip of the rocker arm.

Engine whether new or not.... Setting these Dynamically: I.E., setting with engine running and warm!
Now we are listening to/for a clatter and stopping the clatter at a guestimate of ZERO lash. (unless you have a P&G dial-indicator valve gapping tool) Many of the Hot Rod guys do... well, in my days we did!
biggrin.gif

But this is a completely different approach.... and yet very accurate if you know what you are doing.
I have no issue with this method what-so-ever. Good method and it gets the job done!

My only point in the beginning was, that if done statically and correctly (prior to priming), you will find that you seldom need to go back through these dynamically.
I've been doing this successfully since the 60's. It works for me!

."
 
"Man, we need a "quote&#34

"Man, we need a "quote" feature here like v-Bulletin offers.

Quote:"But, you don't want plunger movement during the zero lash process, correct? <u>If the plunger moved in(down) then the system could be too tight.</u>

I had always thought you needed the lifter plunger fully expanded at the point of adjustment, then the one full turn of the nut depressed the plunger by so many thou. Without it being full of oil, only the light spring is keeping the plunger extended."

That is what this procedure is accomplishing. Setting the plunger to the desired depth.
Remember, the plunger/piston has anywhere from .080" to .100"+ travel within the body..... more on some. (Not valve travel... we're talking plunger/piston travel)

From there, any valve/rocker arm/push rod travel is done via the hydraulic cushion of oil.
This controls ZERO lash also.

."
 
"Al can tell you, the "fee

"Al can tell you, the "feel" required to find that ZERO lash spot is critical on the v-twins, especially give the service interval for the older ones.

I believe that one would want to use the inverse of the rocker ratio if you want to calculate the plunger travel (so divide by it instead of multiply by it)"
 
I'm confused do I (1 a

I'm confused do I (1 adjust cold before starting 2 start it for a minute and shut off while still some what cool 3 warm it up or 4 diff.) before adjusting rocker while spinning pushrod?
 
Do the valve adjustment with t

Do the valve adjustment with the engine cold.

ricardo - I think all the multiplicands are fractional so there are no whole numbers involved. Nothing in my posts infers whole numbers. where did "whole numbers" emerge from?
 
"OH boy.... this gets complica

"OH boy.... this gets complicated to explain. Do you really want to hear this?

I have to ask first....., did you not imply that multiplying a rocker arm ratio X's thread pitch (one revolution) would not equate to plunger/piston travel... given that the values of each are known? (ratio/pitch that is)

Remember... Division and/or Multiplication is a means of quantifying the inverse relationship between the two forms of mathmatics!

This will be fun, but I may have to do it late this evening or in the morning."
 
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