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  #1  
Old 07-21-2021, 01:33 PM
Deckie27 Deckie27 is offline
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Default Ticking and smoke

Hi

Been lurking for a while now.

My Volvo 760 dtic is giving me bother
It has developed a ticking noise
And gone very smokey

Please see video below any pointers on where to start.

Thanking you

https://youtu.be/4rRMW-UZz6M
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  #2  
Old 07-21-2021, 03:12 PM
RedArrow RedArrow is offline
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It sounds similar to when I had an injector fail.

You can try GENTLY loosening the fuel hard lines, one at a time, to find which injector it is.
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Old 07-22-2021, 11:27 AM
Deckie27 Deckie27 is offline
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Cheers red arrow
Tried loosing the hard lines to the injector's near all cylinders effected the running.
None stopped the ticking noise but when I tried cylinder 6 or 1. (Closet to front of car)
When I loosened the hard-line the tone of the engine didn't change most of the smoke stopped. But ticking noise continued.
? ? ?
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  #4  
Old 07-23-2021, 06:51 AM
v8volvo v8volvo is offline
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An injector would definitely be the best first guess. But if the ticking continues regardless of injectors being disabled one by one, it also could be a failed cam follower (lifter).

Your engine is probably a late '80s or early '90s unit? So it would have the hydraulic self-adjusting lifters if so, unlike the solid mechanical shim adjusted lifters we have on the older early '80s US model engines here. The switchover to hydraulic valvetrain occurred in 1987 as best I remember.

The hydraulic lifters are a nice feature since they never need adjustment, BUT they can wear out with high miles and sometimes can suffer failures of the follower surface. See this thread that links pictures of how this can happen, on a slightly different but highly similar engine that uses the identical hydraulic lifters. https://d24t.com/showthread.php?t=2147

Since you did the first test of cracking injectors open to check them and didn't find the issue that way, I think the next step I would try is removing the valve cover and taking a close look at each camshaft lobe and each follower. Probably have to turn the engine over with a wrench a few times to see them all. Look for issues/damage like what the photos above show, OR for a lifter that looks OK in terms of its surface but doesn't seem to be holding pressure and is sitting visibly low in its bore even when the cam lobe is not in contact with it. Some people also like to gently press down or lever down on the lifters using some kind of soft tool (plastic) to check their function. They have internal seals and a piston that can wear out and fail to achieve full valve lift and timing, causing a miss and noise like what you're seeing.

Valve cover removal on your intercooled engine is a little more involved since you have to take the intake manifold extension off, but not bad otherwise.

Welcome to the board! Sharp looking wagon you have there.
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Old 07-23-2021, 12:46 PM
ngoma ngoma is offline
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Did the onset of the excess smoke coincide with the ticking noise?

Oftentimes a mechanics stethoscope can help pinpoint noise sources. Held on each injector. Also on each cylinder's exhaust manifold outlet, also intake manifold connections. One may sound louder, or sharper, or otherwise different than the others. If no stethoscope, a length of tubing, or long handle screwdriver pressed to ear (careful!).

Maybe unrelated but when I hear ticking I say don't overlook the vacuum pump.
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