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-   -   Clack-clack-clack noise? (http://forums.pelicanparts.com/porsche-911-technical-forum/771275-clack-clack-clack-noise.html)

nene 09-13-2013 08:03 AM

Clack-clack-clack noise?
 
Recently, I have noticed that when starting my 86 Carrera from a cold start, I hear a clacking noise (which sounds like the valves) on the drivers side of the valve covers area. It appears that once the OIL hits that area, the sounds goes away (yikes)!!:confused: Any suggestions gents?

Thanx,

T77911S 09-13-2013 08:09 AM

pull the valve cover and check it out. could also be a clogged hole in the spray bar

nene 09-13-2013 08:15 AM

Thanx, I will look into it once I dive in there to do the Valve Job!

Bob Kontak 09-13-2013 01:39 PM

Just talking here. Any change in oil viscosity from the heavier stuff the cars should use?

nene 09-13-2013 07:43 PM

Bob, I did recently did and oil change, but I don't think it's too thick.

Bob Kontak 09-14-2013 07:29 AM

New cars use pretty thin oil.

I don't know enough about oil to advise you. But if you did put oil in yourself and you don't know what the viscosity is, then you might want to replace it with the correct viscosity oil to be sure. That will cost you $75 or so with oil on sale as you probably know.

If you asked what you needed at the parts store and they told you, there is a very good chance it is fine.

Dodge Man 09-14-2013 08:38 AM

Valve Adjust?
 
Since you have to drain the oil to do a proper valve adjust/inspection, you may want to at least see if the rockers have small jiggle(proper crank position required) to see of any valves are too tight. This can be done while you are inspecting the oil sprayers. Do you have start-up smoke? Best of luck. :)

nene 09-14-2013 03:53 PM

Dodge, I do have some smoke on start up. Can loose or tight valves cause smoke (besides tired engine)?

Ronnie's.930 09-14-2013 04:17 PM

Horizontally opposed cylinder engines smoke at startup even when brand spankin' new (it's the nature of the design and has nothing to do with valve lash settings).

Hunt3R 09-14-2013 05:08 PM

Quote:

Originally Posted by nene (Post 7656579)
Dodge, I do have some smoke on start up. Can loose or tight valves cause smoke (besides tired engine)?

My 3.2 over time had started to blow out a white cloud of smoke on cold starts and for the first couple minutes driving off down the road I could see faint black smoke coming around the car as I would slow down to idle at a stoplight. Then I did a valve adjustment and now there's absolutely no smoke at all, none at all when starting up and none at all at idle when warming up. Changed the way my engine sounds now too.

So I'm gonna say yes. And make sure you're using a thick weight oil too like a 20w50. What oil did you put in?

hcoles 09-14-2013 05:24 PM

I have an 89. No smoke at startup or other times.
If the rockers, cam and valve stems are in reasonable shape and adjustment the sound at idle will be like a well oiled Singer sewing machine. Something like that, if you are hearing "clacking" you have some sort of issue. IMHO.

boyt911sc 09-14-2013 07:05 PM

No smoke at 146K miles.......
 
Quote:

Originally Posted by Ronnie's.930 (Post 7656608)
Horizontally opposed cylinder engines smoke at startup even when brand spankin' new (it's the nature of the design and has nothing to do with valve lash settings).

My '89 Carrera with 146K miles does not smoke during cold starts. But my other '78 SC does. And my son's '87 Carrera does not either too. So with my Subaru Impreza.

Tony

lonewolf 09-14-2013 07:22 PM

Quote:

Originally Posted by nene (Post 7655508)
Bob, I did recently did and oil change, but I don't think it's too thick.


Clacking on startup can also be from low oil.
If you did a change recently and before you go taking everything apart make sure you have the proper amount of oil in the engine.

Bob Kontak 09-14-2013 07:55 PM

Quote:

Originally Posted by Hunt3R (Post 7656651)
Then I did a valve adjustment and now there's absolutely no smoke at all, none at all when starting up and none at all at idle when warming up.

Let's think about this for a little second.

The valves move up and down all the time in the valve guides the height of the lobe on the ol' bump stick. That can be measured in fractions of an inch - I don't know, a quarter or three eighths?

You adjusted them this way or that a very few thousandths of an inch in the same direction the cam moves the valve.

I am not seeing any reason why a valve adjustment could cause an improvement in oil seepage through the valve guides.

I am thinking you are merely in the cosmic grace period before the next fog. (See Ronnie's post)

Also, from my experience, blowing smoke on start up is a hit or miss thing. I can go for weeks, even months, with no smoke then it fogs the neighborhood. Like, I should go to jail smoke. Maybe it has to do with where the engine stops?

Ronnie's.930 09-14-2013 08:29 PM

Bob, that is my experience with start-up smoke as well - no visible smoke for weeks, and out of no where, a juicy burst of it. I've experienced this with every opposed cylinder engine I've ever been around (including the Type IV in a 914 I drove for years, and the aircraft engines I've worked on). Of course, none of this with the glorious Opel lump! :D

nene 09-14-2013 08:36 PM

I don't know boys, back in the high school days (1986 or so) I bought my first Porsche (yes in high school) a 1975 911s with 86k miles on it and that thing never smoked and it even had a broken stud (which I thought was a leaking exhaust). Now this car that I have (picture) mainly pumps out smoke on start-up and generally smell the stench when coming to an intersection or stop!

Bob Kontak 09-14-2013 08:39 PM

Quote:

Originally Posted by Ronnie's.930 (Post 7656848)
Of course, none of this with the glorious Opel lump! :D

LOL - For those that never owned an Opel GT like Ronnie and me......... If you have to ask you wouldn't understand. http://forums.pelicanparts.com/suppo...leys/freak.gif

nene 09-14-2013 08:47 PM

Quote:

Originally Posted by nene (Post 7656856)
I don't know boys, back in the high school days (1986 or so) I bought my first Porsche (yes in high school) a 1975 911s with 86k miles on it and that thing never smoked and it even had a broken stud (which I thought was a leaking exhaust). Now this car that I have (picture) mainly pumps out smoke on start-up and generally smell the stench when coming to an intersection or stop!

http://forums.pelicanparts.com/uploa...1379220427.jpg

lonewolf 09-14-2013 09:55 PM

smoke on startup can also be caused by slow closing /sticky the odd time injector or another fuel source.
The tiny bit of fuel washes the cylinder and hence the smoke on startup.
That's why it only happens every now and then .

also if say you started the car but only let run a few secs to maybe check something and then it was off for couple days . it could smoke on startup for a few secs.

As an old pro engine builder told me many years ago ,if it doesn't happen all the time .dont worry about it.

Ronnie's.930 09-14-2013 10:18 PM

Quote:

Originally Posted by lonewolf (Post 7656894)
smoke on startup can also be caused by slow closing /sticky the odd time injector or another fuel source.
The tiny bit of fuel washes the cylinder and hence the smoke on startup.
That's why it only happens every now and then .

Sorry, but this is not at all accurate. It takes far more than a "tiny" amount of fuel to result in cylinder washing (more like a grossly rich running condition, or a water/methanol injection system that is not working properly) and if oil was washed from the cylinder(s) when the engine was not running, then there would be no oil there to burn when the engine is started, and therefor, no startup smoke. The reason that the startup smoke is intermittent is that, due to the cylinder layout, "sometimes" oil, enough to result in visible smoke, travels past the rings, and into the combustion chamber, when the engine is not running.


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