Thread: Harmonic balancer on 454 has 4 timing marks.....

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Originally Posted by repoman3809

So it's in time. The pic with the marks is on #1 TDC.

turn it 180 marks will line up and it will be in phase

well let me know if you need any thing . the 330 hp as a 030 fresh bore very nice all new parts and first time rebuilt fresh 010/010 crank rebuilt rods with arp bolts speed pro hyper flat tops wiill be short block very soon. the other mark 6 roller engine is going to be a 489 with srp flat tops. i will very soon have a pair of 511s or 513s mark 4s they will be four bolt mains blocks i have. i will start on them next week , H beam rods .forged pistons 4340 scat cranks all new parts .i have one 489 I beam billet rod6.385. and scat cast steel crank .Icon pistons forged pistons all fresh machined short block on the E bay right now all done

Everything clear now, Repoman??

Everything clear now, Repoman??

I don't know anymore. Go back to the original post, I put my motor knowledge was 5 of 10, at best. Maybe I should edit that to 3 or 4. LOL

Ok so the crank and cam are in time with each other, but the dist is out. I need to set to cam@6-crank@12, reset dist to #1. And this would solve the hard starting, crappy idle and base timing issues. Right?

It doesnt solve the low compression readings, since cam and crank are in time. Unless the roller rockers are unadjusted or incorrectly adjusted. But likely isnt the whole problem, even if it is a problem. So I still need to do a leakdown and see just what it is causing the low reading. Then proceed from there.

IF, you want #1 cylinder to be the "lead" cylinder that you will set ignition timing by. Then you need to rotate the crank 1 more time.
With #1 cylinder at TDC, and both valves closed, the cam gear dot needs to be at 6 o'clock and the crank gear dot at 12 o'clock.
I would advise you to do this so that ALL OF US here are on the same page. What that picture shows is that cylinder 6 is the "lead" for timing the ignition.

I am using the term "lead" for lack of a better word. This is probably why your timing is shown so far off. Hope that helps...

Originally Posted by 34_40

IF, you want #1 cylinder to be the "lead" cylinder that you will set ignition timing by. Then you need to rotate the crank 1 more time.
With #1 cylinder at TDC, and both valves closed, the cam gear dot needs to be at 6 o'clock and the crank gear dot at 12 o'clock.
I would advise you to do this so that ALL OF US here are on the same page. What that picture shows is that cylinder 6 is the "lead" for timing the ignition.

I am using the term "lead" for lack of a better word. This is probably why your timing is shown so far off. Hope that helps...

Come on fellows, this is not rocket surgery. When you assemble the motor and put the dots together, cam at 6 and crank at 12, the motor is set up at that point to fire #6. You have to rotate the crank one full turn, so that the cam is at 12 and the crank is at 12 in order to fire #1. I have no idea why the engineers at GM marked the sprockets that way, but they did and we have to know to rotate the crank one full turn after we put the motor together so that we can fire #1. One more time, 12 x 12 to fire #1.

If it wasn't a science the poor OP would have a running motor by now!

I was under the impression 12 and 12 was to fire #1. 6 to 12 was to ease the installation of the cam, given that the dots were right next to each other. This would fire on #6 TDC. Then you rotate one turn to 12-12 and now your firing #1 TDC.

Techinspector1 seems to agree with this, so does the tech manual pic I found(top of page, post 46).

I guess I'll try and find a 454 Haynes manual.

In the meantime. Tomorrow I'll likely be pulling the valve covers, doing a leak down test. I think the proper way to do that is start TDC on #1, check valves r closed, test #1. Then move crank 90 degrees(to #8, next in firing order), make sure valves r closed, test. So on and so forth.

your making this way to hard here ?? who cares if 12 and 12 is tdc on 1 you do not need to know that. what you need to know if the cam timing is in phase with gear marks and when you degree the cam that the numbers come in to the sheet on the cam card or work out the numbers. honestly i could care less to were the chain is marked to what cylinder is at tdc when there marked as long as the cam is in phased . built a hell of alot of engines not giving it any thought . dumb ? there dumb thing that make engines fail like no piston to valve clearance . rods out of round. the long list of dumb thing. dwelling on this is not helping you. if the cam is in phase . the engine still has one low bank that has nothing to do with wasting time on why the marks should be at 12to 6 for #1 and not #6 you have ether bent valves/pushods on the one bank very will could be bent intake valve .or a wiped cam on one side. hard to think all holes are low on one bank less that head had wrong springs on that bank or adjusted so far down all valves are not closing . if you did wipe the lifters do not force many out if you do you will cut the bores up.

Originally Posted by pat mccarthy

your making this way to hard here ?? who cares if 12 and 12 is tdc on 1 you do not need to know that. what you need to know if the cam timing is in phase with gear marks and when you degree the cam that the numbers come in to the sheet on the cam card or work out the numbers. honestly i could care less to were the chain is marked to what cylinder is at tdc when there marked as long as the cam is in phased . built a hell of alot of engines not giving it any thought . dumb ? there dumb thing that make engines fail like no piston to valve clearance . rods out of round. the long list of dumb thing. dwelling on this is not helping you. if the cam is in phase . the engine still has one low bank that has nothing to do with wasting time on why the marks should be at 12to 6 for #1 and not #6 you have ether bent valves/pushods on the one bank very will could be bent intake valve .or a wiped cam on one side. hard to think all holes are low on one bank less that head had wrong springs on that bank or adjusted so far down all valves are not closing . if you did wipe the lifters do not force many out if you do you will cut the bores up.

I really didnt intend on making this hard. I posted that pic and was told it was out. I didnt think it was, so when I seen that it might be. Well, I figured that was a lot of my problem. So it was focused on. I mean, I don't wanna go the rest of my life not knowing the proper way to set timing on a 454. While I didnt set this chain. I was always under the impression 12/12 was the final mark with dist in and on #1.

As for using a degree wheel, I have no clue. So maybe I need to switch back to stock cam, or learn to use it, or just hire a pro like you.

Again, I totally agree something is amiss with the 5 low reading cylinders. My intention is to figure that out and then go from their.

Also Pat, if valves and pushrods are bent. Whats my chance that the pistons made it though ok?

12 and 12 is nothing to care about i think i told you your 180 off from were the dots needed to be. not moving cam or chain just to turn the crank 180 to line up the timing dots so the cam was in phase so you could check if the cam was off a tooth or more as for not checking the cam this is were you start with dots 6:00 and 12:00 to see if the cam timing is off . for a cam thats not stock for dumping one in i check the events .no way in hell do i just stab them in seen them off 8 degrees off on the pin .it ran good ? i was thinking it never did ? still its one of them deal s were checking that cam in phase dot to dot .take valve covers off look at tops of rocker studs side to side even with. valve work.seat work . milling . the nuts all should be very close side to side .if the nuts are drove down a lot on that bank some thing is going bad. check by eye or machine ruler if any springs set lower it very well has bent valves

Repoman, seems to me you have a good handle on #1 at TDC now, or close enough to true TDC for the valves on #1 to be closed, and your step-by-step process should give you some more idea about exactly which cylinders have problems, and whether it's valves hanging open or not. It doesn't sound like you're planning to pull the timing chain, so talk about degreeing the cam or setting up the engine is not really of much value for where you are in the process, IMO. Now it may be that whoever installed that hot cam didn't degree it right way back when, but for now you're assuming that the engine was set up right because it ran right at one time. From what I've read you spent some money on what you were told was a good engine from your boat dealer, you're finding that it may not have been quite as good as you were led to believe, and now you're trying to understand just how bad it is before you decide to pull it out and either start fresh, or maybe have that one rebuilt. I would be doing exactly the same thing before I made a decision on several thousand dollars!

If your Saturday is going to be dedicated to this mystery I hope you have your answers early, and can then move on with a decision that gets you back on the water enjoying the boat. Best of luck to you!

Originally Posted by rspears

Repoman, seems to me you have a good handle on #1 at TDC now, or close enough to true TDC for the valves on #1 to be closed, and your step-by-step process should give you some more idea about exactly which cylinders have problems, and whether it's valves hanging open or not. It doesn't sound like you're planning to pull the timing chain, so talk about degreeing the cam or setting up the engine is not really of much value for where you are in the process, IMO. Now it may be that whoever installed that hot cam didn't degree it right way back when, but for now you're assuming that the engine was set up right because it ran right at one time. From what I've read you spent some money on what you were told was a good engine from your boat dealer, you're finding that it may not have been quite as good as you were led to believe, and now you're trying to understand just how bad it is before you decide to pull it out and either start fresh, or maybe have that one rebuilt. I would be doing exactly the same thing before I made a decision on several thousand dollars!

If your Saturday is going to be dedicated to this mystery I hope you have your answers early, and can then move on with a decision that gets you back on the water enjoying the boat. Best of luck to you!

Thank you! That's pretty much it in a nutshell.

When I posted that pic of the timing chain marks and was told it was 180 out. I looked though every book and every internet page I could find, with very little hard evidence of the correct marks(everyone differed). So it made me mad. I figured I needed get an outcome at least for next guy who may need to reference this thread for his/her problem.

And for that person, here goes. Please correct me if it's wrong, but this is what I've gathered from everything I've read(which was way too much).

Technically if your pulling your running, stock motor apart, you will find the marks at 12/12.

But if your building a motor 6/12 is right. Most articles will reference these points for easy cam installation, while setting up your timing chain and gears. The article then usually follows the rest of your motor build, before later getting back to installing dist and setting up base timing. It's here where it's likely not even mentioned, but those marks are moved to #1 TDC or 12/12.

Of course this is if your working with stock components, which I'm not. I have no business touching a degree wheel and given my cam specs(which Im still waiting on), who's know how far off I am.

BTW. Rain held me off this morning. So maybe tomorrow.

It's nice and sunny now, and I'm finished with the other stuff I wanted to do today. So I may get around to it after all.

That's what I'll do Pat. I line the marks, pull the covers and check the nuts. As well as a leak down. I'll keep posted.

I also did do any eyeball test on the stud heights. They all appeared close on each bank. I took a straight edge with me, the most I could see was maybe a quarter inch difference, really most where within an eighth though. I couldnt really tell on the springs, I was hoping to get a pic for ya Pat.

I did see some scarring on the outside of the #1 topside rocker(bronze color wore off, bare metal shows) . It looked as if it was rubbing the valve cover. I didnt see anything on the valve cover though. Also most rockers have the same type scarring on the around the stud and lock nut. I assume that is likely normal. But I don't know, you guys tell me.