85 720 4x4

[Seven20LAliving]

I just brought a 720 4x4 and it needs the timing chain replacement (due to making a lot of noise). I took in to get a price for the repair and was quoted $500 total. Just want to know what's the typical price for this repair? 

[datzenmike]

If it includes the parts which include new guides and a tensioner, I guess that's what a mechanic will want.

 

 

Maybe the valve lash needs setting? Feeler gauge and a wrench or two set all to 0.012" on a hot engine. Takes less than half an hour. But do it yourself. See if that fixes it.

 

There's also an old saying that 720s like to tell you when they need an oil change. I've heard a couple of owners say the engine got quiet right after an oil change. 15w40 Shell Rotella T4 and a WIX or NAPA Gold filter. Don't use today's oils, get a light diesel oil like Chevron Delo 400

[MaxChlan]

8 hours ago, datzenmike said:

There's also an old saying that 720s like to tell you when they need an oil change. I've heard a couple of owners say the engine got quiet right after an oil change. 

This! Instead of an automatic service interval like on modern cars, my truck tells me every time it needs an oil change with small changes in engine sound. 

[datzenmike]

The Z and L series are almost the same internally except for the heads and displacement. Haven't noticed this on them.

 

Valve lash, now that's another story. That can cause a lot of clatter and should be checked.

 

If oil is clean I wouldn't worry about... if it's black and you don't know when it was changed last I would change it.