Strange Engine Noise

niall · niall's Garage

Hi

I had a recent once off event with my 3.2 1986 engine. The engine is a good reliable motor, starts first time every time and runs smooth.

Recently I parked the car on the street for an hour and when I came back the motor started no problem, but there was a quite load rattle / knocking noise from the right bank, I could not tell if it was piston of head related but it a very disturbing noise (sounded very expensive). I noticed it once I was just underway and I pulled over asap popped the hood and listened it lasted about 2 minutes.

But just a quickly as it appeared it faded away and the car was back to its usual reliable self again, weird. And since then It has been out a few times with no issues.

Any comments would be helpful, as I'm still puzzled.

Niall

Paulporsche · 10-14-2008, 02:00 PM

When the chain tensioner fails, the noise it makes is usually described as chains rattling in a garbage can. Did it sound like that? If you search you may find a sound clip.

niall · niall's Garage

The chain tensioner did cross my mind, because the noise started after being parked up and went away shortly after start up. It was quite a chaotic noise when the engine was idling. But as it has not happened since I can only guess.

I did have the car parked on a hill facing upward, I wondered could it have been something to do with oil draining from the tensioner but dismissed that as unlikely.

3.2 CAB · 10-14-2008, 02:47 PM

Do you have the original style tensioners, or the pressure fed Carrera style?

ben parrish · 10-14-2008, 02:58 PM

86 has Carrera tensioners.
Watch it carefully. Perhaps chance the oil and look to see if you see any metal...check the filter also by splitting it.
Ben

niall · niall's Garage

Will do, good idea.

3.2 CAB · 10-14-2008, 03:49 PM

I asked about what type of tensioners from what I saw in the signature. Was not sure what car had what?? O-well.

hcoles · 10-14-2008, 04:34 PM

check tensioners (not really sure how) I guess pull the covers, remove and see if they hold pressure.. I would also check that all the rocker shafts are in place and don't look like they have moved lately.. might as well check head bolts while your in there..and valve clearances.. but that's probably ok. If you were pulling the tensioners I would suggest adding the Jerry Woods slugs/spacers inside as a layer of insurance..