Where the heck are the timing marks on my 427?
 

I thought getting the engine to TDC would be the easy part of pulling the distributo, but it ain't working out that way so far. I see the mark on the balancer, but I can't find the "pointer" on the block I expected to find to line it up with. I've got the chassis service manual, but it just shows a generic location for all '69 engines (driver side of the water pump), but by gosh I ain't go no marks there, though the truth is, I really can't see much of the block behind the balancer at all. Somebody wanna gimme a clue?

JB


[Modified by JB, 3:06 PM 6/1/2002]

Re: Where the heck are the timing marks on my 427? (JB)
 

TTT.

C'mon, somebody's gotta know. I jacked the car up and looked at it from underneath and I think I see a tab sticking out from the block more or less where the service manual said it would be, but so far as I can tell, there is absolutely no way that tab could be seen from up top as it is blocked completely by the water pump and some sort of idler arm. I'm not actually supposed to time the car from underneath am I?

JB

Re: Where the heck are the timing marks on my 427? (JB)
 

I am not sure on the big blocks but on the small block cars the timing tab ws made on the timing cover and would be just above the balancer so you can time it from the top.
If someone has changed the timing cover to an aftermarket cover or broke the timing tab off you can by a timing tab that bolts on with 2 of the timing cover bolts.
Hope this helps

Re: Where the heck are the timing marks on my 427? (candyapplevette)
 

Have you put a timing light on it yet? It can become more obvious when the dot is frozen by the strobe light. On the other hand, the tab should be visible from the top, tho somewhat obscured by paint and grease. Sounds like yours may have moved? If you dont get any better advise I can take a pic of mine in the morning. MJ

Re: Where the heck are the timing marks on my 427? (JB)
 

My L36 tab is located on the drivers side crank pully.

--Andy

Re: Where the heck are the timing marks on my 427? (andyg)
 

Andy--It's on the pully itself? I'm having trouble picturing that. Do you mean it's actually attached to or over the pulley in some way?

MJ, I'd sure appreciate that photo. Here's a rather crappy photo I just took of what I see looking down from the driver's side at the balancer. As you can see (sort of), I can only see about an inch of the balancer between the water pump housing and that idler pulley thingee just below it.

https://temp.corvetteforum.net/c3/jb//balan1.jpg

JB




[Modified by JB, 12:42 AM 6/2/2002]

Re: Where the heck are the timing marks on my 427? (JB)
 

TTT.

Still trying to get to TDC. I realize I can get there by pulling a valve cover and looking at the valves on the #1 cylinder, but I'd rather not do that. And I'd like to have the marks for setting the timing. One of you guys with a rat, is that tab with the marks behind that idler pulley in my pic, and do I need to remove that pulley to see it?

JB

Re: Where the heck are the timing marks on my 427? (JB)
 

Ok, how desparate are you? If you're getting frustrated, try this:

Pull the #1 spark plug, and stick a wooden dowel into the hole (make sure the dowel is long enough not to drop in). You can turn the engine over to find approximate TDC (if you want to make sure you're on the compression stroke, put your finger over the plug hole and get a helper to turn the engine over - when you feel the air pressure trying to push you finger off, you're on compression). Then your timing mark on the harmonic balancer can be used as a reference point to try to find the tab, or mount a new one if the old one's missing.

Re: Where the heck are the timing marks on my 427? (JB)
 

If you haven't removed the distributor yet, align the rotor with the #1 wire position of the cap. That will get your engine in the proper postion. That will also bring the mark on the balancer around to where your tab is (or where it once was) and help you know where to look. If you're reinstalling the same distributor, put a mark on it where the rotor is pointing and a mark on the manifold that aligns with a mark or some part of the housing. When you reinstall, if the engine hasn't been rotated, lining up the marks will let you know it's in the correct position and your timing should be very close to where it was before. If you're replacing the distributor, just make a mark on the manifold that aligns with the rotor. Install it with the rotor pointing at that mark and the distributor will be in the correct position. Rotate the housing until the rotor is aligned with the #1 position of it's cap and your timing should be close to where it was before.

Re: Where the heck are the timing marks on my 427? (JB)
 

As said elsewhere, the timing tab with timing marks is attached to the timing chain cover, above the crank pulley. (sounds like you can see it from underneath) It is visible from the top past the radiator hose and p/s pump. There is no "idler arm" of any sort above it on my L36. Your fan also looks not original, must be an aftermarket flexfan. Mine has the stock fan with the thermatic type of fan clutch.

The rearmost belt drives the water pump from the crank pulley directly without any idler or tensioner. If yours has these components, perhaps someone else here knows what they are about.

Good Luck!

Joe
69 427L36 M21 3.08 White Coupe

Re: Where the heck are the timing marks on my 427? (JB)
 

I'd take a picture, but my car is in the shop for tranny and t-arm rebuilds. The tab is mounted to the block behind the crank pully drivers side. I believe it goes in 10 deg in either direction with a 0 in the middle of the tab. I think the 0 is the only number on the tab. I have to look between the alternator and water pump to see it.

---Andy

Re: Where the heck are the timing marks on my 427? (jyounane)
 

Vetterodder--if I do it that way it'll either be TDC or 180degrees off of TDC, so I guess I'd have a 50/50 chance. :D

Jyounane--the flex fan is definitely aftermarket, but my AIM manual shows the 427 having a "Pulley Asm--Idler" right where I've got one, on the driver's side & below the water pump (you can see it in my pic above). I'm thinking I'm just gonna pull the darned idler/tensioner thingee and if the belt flies off when I'm trying to time the sucker, why then it just freakin' flies off.

Thanks for the help, guys.

JB


[Modified by JB, 11:36 PM 6/2/2002]

Re: Where the heck are the timing marks on my 427? (JB)
 

JB, my L36 timing tab is right where your idler pulley is. It's a metal tab that sticks out about 1/4" above the balancer. If you took that picture on my engine, you would be looking right at the timing marks. If it's there, you'll have to move the idler to see it. The tab is pretty big, probably an inch wide and two inches long.

-Joe


[Modified by Flareside, 8:15 AM 6/3/2002]

Re: Where the heck are the timing marks on my 427? (Flareside)
 

Cool. Now, what I want to know is, does anyone else have this freakin' idler? Is this a part that tends to get "lost" because mechanics hate it 'cause you can't see the timing tab? Or is my AIM wrong and my car's got a bubba-toy plugged into the front of the block?

JB

Re: Where the heck are the timing marks on my 427? (JB)
 

Well, here are my pics. Better late than never I hope, but if you had a timing tab like this you would surely be able to see it. I have no idea if this is factory or added on later. I dabbed a little white paint on a couple of the marks to see them better.

Here is the view from the drivers side:

https://temp.corvetteforum.net/c3/mnjack//timetab1.jpg

If you can't quite make out the timing tab, here is the same pic:

https://temp.corvetteforum.net/c3/mnjack//timetab1a.jpg

Here is a closer look:

https://temp.corvetteforum.net/c3/mnjack//timetab2.jpg

And the same pic with the timing tab marked:

https://temp.corvetteforum.net/c3/mnjack//timetab2a.jpg

And here is a closeup:

https://temp.corvetteforum.net/c3/mnjack//timetab3.jpg


Darn it looks dirty in there!!! :eek: MJ


[Modified by MNJack, 1:09 PM 6/3/2002]

Re: Where the heck are the timing marks on my 427? (MNJack)
 

Nice pics, MJ. Thanks! You're right, though, might be time for you to break out the simple green and a toothbrush. Need that block to look as good as your wiper door actuator does now. :D

Doesn't look like you have that idler pulley, either. Does anyone but me have the thing on their L-36?

Re: Where the heck are the timing marks on my 427? (JB)
 

Follow up--got the idler pulley out of the way, and lo and behold, there's the timing tab. Bumped the motor to TDC, yanked the distributor and the manifold. Now the manifold is headed out to the machine shop to get that broken bolt out and to get bead blasted. :D

I'd still like to know why no one else seems to have that idler pulley.

JB

Re: Where the heck are the timing marks on my 427? (JB)
 

Idler=AC

Here is a jpg of the belt routing
http://members.bellatlantic.net/~and...lt_routing.jpg

If car was ordered with C60 option(AC) then belt routing was one of the lower two pictures. I have the upper right picture minus the AIR pump.

--Andy


[Modified by andyg, 7:20 PM 6/3/2002]

Re: Where the heck are the timing marks on my 427? (JB)
 

JB, nope. The distributor runs at half engine speed and, if it's installed correctly, the rotor only points to the #1 cylinder when it's in the correct firing position. By the same token, if the rotor points anywhere other than the #1 position, you'll know that it's has been installed wrong just by looking. If you pointed the rotor 180º from the #1 position, then you'd be 180º.

where is the timing tab?
 

I too have this retarded idler pulley on my 1970 corvette with a 454 stuffed in it....I was wondering the same thing I can not see the timing tab so if I pull off this ridiculous idler pulley assembly I will see it assuming its not broken off? I have 2 aftermarket chrome timing chain covers and they dont have timing tabs on either of them...I bought a billet pointer for my supercharged engine on my last car and it had a built in timing light and I got a piston stop bolt sleeve thing so I could locate tdc
​​​​​​​#1 from both directions and move the pointer to line up with the balancer mark though with a bds blower you lose the balancer and install a keyway billet hub instead and use a timing tape and like using a degree wheel you hit the piston stop bolt by turning the engine clockwise thrn counter clockwise and you have maybe 1/2 in between tdc from both directions so I marked it then peeled and installed the timing tape to find exact tdc #1 and set the billet pointer to that middle spot and the timing tape had its main center mark perfect and each time tge engine