1970 383 Timing Chain

[mykers]

Hello All Happy Holidays,

Couldn't find/search anything on my question so edgeUmacate me please!

70 383 timing chain: Do I have a single bolt or a triple bolt? I want to do a chain refresh and want to know if im walking into a **** storm, which way the winds blowing...oh and for ordering purposes

Also, just to confirm a double-roller should be fine I imagine with the stock cover, correct?

As usual thanks for your help and Happy New Year!

 

[mykers]

Or from a different perspective do I have a single or three-bolt camshaft? Is there anyway to know without tearing down the motor?

 

[miller]

Stock 383 will have a one bolt cam. Lousy timing chain. Positively go double roller!

 

[Demonic]

^^ That's right. I was surprised that my 383 4 bbl had a nylon gear.

 

[Bill Monk]

Stock 383 will have a one bolt cam. Lousy timing chain. Positively go double roller!

double roller is the only way to go and correct on the one bolt.

 

[miller]

Also, just to confirm a double-roller should be fine I imagine with the stock cover, correct?

Yup, slap right in!

Perspective? How's this grab ya?

'Somehow' a friend of mine talked me into helping him on his early Toyota! Okay, for a friend. Suspected a timing chain, since the car had a quarter million miles on it! Wow. I actually thought it sported a timing belt.
Anyway, long story short, pulled the cover...lo and behold...stock with a double row roller. Still as tight as the day it was put on.

 

[mykers]

And bear with me because I’m back in the game after being out for 13 years, but I should need:

Tools:
Basic tools: sockets, breaker bars, wrenches, etc.
harmonic balance puller

Parts:
-Double roller timing chain with gears
-Gaskets: water pump housing, thermostat, water pump, timing cover, timing cover to oil pan gasket and is there a seal in the timing cover?
-Possibly new bolts
-Lube for chain? Or will mystery oil work?
-the usual coolant (does the oil need draining for this?)

Thanks for your help guys. Really appreciate it.

 

[Bill Monk]

And bear with me because I’m back in the game after being out for 13 years, but I should need:

Tools:
Basic tools: sockets, breaker bars, wrenches, etc.
harmonic balance puller

Parts:
-Double roller timing chain with gears
-Gaskets: water pump housing, thermostat, water pump, timing cover, timing cover to oil pan gasket and is there a seal in the timing cover?
-Possibly new bolts
-Lube for chain? Or will mystery oil work?
-the usual coolant (does the oil need draining for this?)

Thanks for your help guys. Really appreciate it.

Looks like you have a pretty good handle on it, there is a seal in the cover for the crank and I would replace it since you will have it apart. I just smear a good break in lube like comp cams on the sprockets because it's easier to deal with than oil dripping all over the place but any oil will work. You will need an oil pan gasket because that's what seals to the bottom of the timing cover so yes on the oil change. Also need a fuel pump gasket unless you are using silicone. Shouldn't have to remove the thermostat but I would so that you can get everything cleaned up good before reinstall. ALWAYS NEW GRADE 8 OR BETTER BOLTS. You can probably get by with not replacing the harmonic balancer to crank bolt because it's such a heavy fastener, just clean the threads well and oil it before reinstall.

 

[Daves69]

........and is there a seal in the timing cover?

Yep. I believe there is a timing cover seal kit that provides everything you need. For example........
https://www.pricefalls.com/product/...tent=PLA&campaign=278176230&ad=75728885230018

-Possibly new bolts

Depends on how the old ones come out after cleaned up and your desires.
I believe one WP bolt requires removal of a heater hose nipple to change. Could lead to more work for you.

does the oil need draining for this?

No, but it's a good idea to change it. As you remove the cover you will likely drop some gasket material into the pan. You may or may not be able to retrieve it. Easier to retrieve remnants if the pan bucket is set back.

Cover the radiator tubes with a piece of cardboard if you don't remove it.
Fill the oil filter at least half full and spin it on quickly if you're replacing.

 

[mykers]

Thank you for all the help! Anything else I’m forgetting feel free to add.

 

[mykers]

oh, another thought...this would probably be a good time to check my fuel pump push rod right?

 

[miller]

double post

 

[Bill Monk]

oh, another thought...this would probably be a good time to check my fuel pump push rod right?

sure, you will have it out anyway

 

[mykers]

Alright guys I got a question. I finally got around to dismantling my motor to replace the timing chain. I have done this before twice on an Oldsmo and Pontiac (years ago). Anyhow, I used a piston stop; clockwise and counter to find TDC.

Moving forward, upon dismantling I find the timing marks at 12:00 and 12:00. WTF?

Does this mean i miss-used the piston stop on #1 and instead managed to put #6 at TDC? I’m confused and have no more hair to loose

How do I proceed? Thanks guys for your help. Very much appreciated.

 

[PP1RT]

Your 180° off. Cam turns at half the speed the crank does. Turn the crank one more revolution with the chain still on.

 

[451Mopar]

On the cam, straight up or down is OK. If you want to roll the engine over to 6:00 cam and 12:00 crank, not a big deal for installing the cam, but I think that is TDC cylinder #1 overlap? I think 12:00 and 12:00 is TDC #1 ignition? With the rockers installed, make sure to turn the engine over with the timing chain attached so there is no piston to valve contact. Otherwise, remove rocker arms so all the valves are closed and just spin the cam to the 6:00 position if that is how you want to align the timing marks.

 

[miller]

Maybe too late?
Did you turn the engine over, by hand, to bring the timing mark to TDC? That's the first thing, that should have been done, before turning a wrench. Should have just been able to get TDC, just using the timing mark, not using a piston stop.
So you understand...with the timing mark at 0...puts #1 at TDC. But, like building a fresh engine, setting up crank/cam timing (for dot to dot on the timing chain) #1 is at TDC EXHAUST stroke. Both #1, and #6 are at TDC, #6 on compression stroke.
Confused yet? Hell, I am! The way it is.

Your just replacing the chain. Before pulling the old one, should take note where the gear dots are, and go back on at the same location. Is that what you did?

 

[IQ52]

Before installing the timing chain, place it in a motor oil bath for a few hours and stir it around in there a few times.

 

[mykers]

I haven’t replaced the chain yet. Old one is still on. So I suppose this brings two questions due to the screw up. First if I have to rotate the engine what’s the best way? Reassembly halfway? Or is there a way to turn the motor with the timing chain exposed/void of the damper. Second: if I replace the chain at 12:00 and 12:00 (or can I replace it this way) is that okay? Seems to me this would be fine since not a damn thing would be advancing and I’m putting it back 100% the way it came off at marks at 12 and 12. Advice?

 

[mykers]

Also should be noted that what I thought was TDC with the piston stop was also lined up with 0 on the timing chain cover