Timing chain replacement?

1980-1986 Datsun 720 forums. All 720-specific topics and discussion can be found here.
marleyone
Posts: 8
Joined: Sat Nov 14, 2009 9:53 pm
Car: 1984 2wd Nissan Pickup

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I am in the midst of replacing a blown head gasket and wondering what more I should do while I have the head off.

Is there any way to tell if the timing chain should be replaced? I would think there is a way to measure link length to check for stretching but I haven't been able to find that info. And I've heard that chain failure is a BAD thing for these motors.

My truck has 210K miles but is on its second motor and I have no idea of this motor's history.

Thanks for the help!


dogred
Posts: 205
Joined: Sat May 16, 2009 10:15 pm
Car: 1983 D720

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When in doubt replace it.

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PEZi
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^ basically that

if you're in there already... there's no reason not to do it, HOWEVER, its not the chain that fails as often as the tensioner... your chain is probably still good... just replace the tensioner if you don't want to do the whole chain

flinterman2000
Posts: 1011
Joined: Mon May 04, 2009 5:32 pm
Car: 2000 Nissan Wingroad, 85 Datsun 720 Pick Up.

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PEZi720 wrote: HOWEVER, its not the chain that fails as often as the tensioner
Don't forget the ladders. They should be changed when changing the tensioner.

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bracktheron720
Posts: 202
Joined: Sat Oct 24, 2009 8:39 pm
Car: 1984 720 with 1980 datsun front end,1972 yamaha cs3

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so iv got the 84 z24 and and it sounds like its got a spray paint can in a paint shaker under the hood...lol well not that bad but i was told chain tensioner was going bad..anybody got any pointers on doin it??

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PEZi
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well... its more or less self explanatory once you get into it... but remove front cover (remove anything that blocks you from being able to do so) and then change

there's more to it involving timing etc but that's the basis of it

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turbojunker
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Joined: Sat Dec 19, 2009 8:51 pm
Car: 79 510, 81 720, 72 510-RIP

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bracktheron720 wrote:so iv got the 84 z24 and and it sounds like its got a spray paint can in a paint shaker under the hood...lol well not that bad but i was told chain tensioner was going bad..anybody got any pointers on doin it??
I'd check the valve lash before I tore into my timing cover.

flinterman2000
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Joined: Mon May 04, 2009 5:32 pm
Car: 2000 Nissan Wingroad, 85 Datsun 720 Pick Up.

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Turbojunker is right. Check the clearance on the valves before attempting to change the tensioner. But once its ok, set No1 at TDC. Then remove the fan and water pump, the crankshaft pulley, the rocker cover and the front cover. Taking a piece of wire, tie it around the tensioner and tensioner shoe. You can remove the chain in two ways; either by removing the master link or by taking off the camshaft gear and removing the chain whole. You can then remove the tensioner. Inspect the ladders which guide the chain before and after the camshaft gear. The ladders have a rubber coating and once this is worn the chain would start making noises. Installation is the opposite of removal.

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bracktheron720
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Joined: Sat Oct 24, 2009 8:39 pm
Car: 1984 720 with 1980 datsun front end,1972 yamaha cs3

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awesome!! thanks!! im very new to these little engines im an oldsmobile guy so this is by far the smallest and lightest thing iv ever owned!!give me a big block and im good but this thing im lost lol...im guessin i use a feeler gauge???to check the lash...no idea though and if so anybody got the specs for it??

flinterman2000
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Joined: Mon May 04, 2009 5:32 pm
Car: 2000 Nissan Wingroad, 85 Datsun 720 Pick Up.

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bracktheron720 wrote:im guessin i use a feeler gauge???to check the lash...no idea though and if so anybody got the specs for it??
Right on. Here in the Caribbean the largest engine we got was the L18 or SD22, so one of the americanos would have to give you that if its a Z22 or 24.

dlarsona
Posts: 8
Joined: Mon Dec 21, 2009 9:46 am
Car: 1981 Datsun 720 and 1984 Nissan 720 king-cab 4x4's

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You might not even have to remove your valve covers - check your timing first. If I remember right, the '84 z24 should be timed at only 3 degrees BTDC. Much more than 5 degrees and mine sounds like a paint can too....

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PEZi
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^ for a stock carb yes

mine is at about somewhere around +16 or +18 BTDC

Munkibishi
Posts: 3
Joined: Mon Mar 04, 2013 12:25 am
Car: 1985 Nissan 720 2.4l king cab

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Ok I am new to rebuilding this engine, and I know about the wooden wedge of grace, but can anyone help me with the 'trick' to getting the timing chain back on? Like how to get the tensioner on there and the timing cover and all, thanks

eastinthetinman
Posts: 1
Joined: Wed Oct 18, 2017 6:18 pm
Car: 1983 Nissan 720 4WD

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i took my timing chain cover off and i dropped the chain then the timing chain tensioner popped out and i can't get it to stick back in its hole it just springs back out when i try. If anyone has any tips on how to make it stay in that would be great.
1983 nissan 720 4x4


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