mattyb Donating Members 1,097 Member For: 16y 5m 2d Gender: Male Location: Gold Coast, QLD Posted 13/12/09 07:33 AM Share Posted 13/12/09 07:33 AM (edited) Thursday arvo, I was heading to rocky with the wife and after overtaking a truck and hitting around 120kph (didn’t rev it much) and backing off the throttle heard a tinny ‘knock knock knock’ sound coming from the front end of the car. It stopped after about 3 or 4 knocks. I stopped the car and had a look under the car and bonnet before heading on our way again. A few Km’s down the road I eased the throttle on to overtake another truck maxing my speed at about 115 this time and again as I backed off the throttle the knocking sound returned, only this time it didn’t disappear.I’ve attached a video file that captures the sound pretty well and am wondering if you can give me your thoughts. 8 friends who are fitters and mechanics have looked and listened and so far I’ve been told everything from bearings, to rods, and rockers. The car runs fine, except for the noise from the motor, I know this as I had to drive it about 10 k's back to a roadhouse so it didn't tay stranded by the side of the highway, it doesn’t sound like its missing, and the exhaust smells fine, there is no water in the oil either. The only hints I can give you is that when we put a screwdriver on the block you can’t hear the noise (through the screwdriver), when you put the screw driver on the head you can hear the tinny knock really amplified. It also seems as though the sound is coming from the front half of the motor.Any help you can give me would be great. <object width="425" height="344"><param name="movie" value=" &hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src=" &hl=en_US&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object> Edited 13/12/09 07:36 AM by mattyb Link to comment Share on other sites More sharing options...
baf6 Member 139 Member For: 15y 6m 29d Posted 13/12/09 07:42 AM Share Posted 13/12/09 07:42 AM (edited) sounds like an exhuast manifold leek Edited 13/12/09 07:43 AM by baf6 Link to comment Share on other sites More sharing options...
millers Member 113 Member For: 16y 5m 15d Posted 13/12/09 07:48 AM Share Posted 13/12/09 07:48 AM sounds a lot like neos engine. we were convinced it was coming from the front of the head but it turned out to be 3 bent rods :( Link to comment Share on other sites More sharing options...
Ace blind leading the blind Member 3,657 Member For: 16y 2m 5d Gender: Male Location: Mt Alford, Queensland Posted 13/12/09 07:49 AM Share Posted 13/12/09 07:49 AM sounds like your missing a bolt out your exhuast manifold or turbo housing - well that is what mine sounds like when the bolt falls out the turbo once every 6 months Link to comment Share on other sites More sharing options...
gravelrash Member 211 Member For: 21y 10m 13d Gender: Male Location: Dalby, QLD Posted 13/12/09 08:12 AM Share Posted 13/12/09 08:12 AM matt, when we unloaded the car off my trailer at your house I stuck my hand down the Lh side of the block whilst running. about 3" back from the oil filter I could feel where the knock is coming from. I would say it has bent #3 or #4 rod and is just tapping the block, you may be lucky and get away with just a set of "BIG ASS RODS" and brgs so long as it hasnt fractured the block anywhere. OR a complete FG F6 short motor.that's my thoughts anyway...Larso:) Link to comment Share on other sites More sharing options...
Ace blind leading the blind Member 3,657 Member For: 16y 2m 5d Gender: Male Location: Mt Alford, Queensland Posted 13/12/09 08:19 AM Share Posted 13/12/09 08:19 AM man it must be a very different sound in real life then on the video cos on the vid if definately sounds like an exhaust leak for your sake dude I hope gravelrash is wrong (no offence intended) Link to comment Share on other sites More sharing options...
gravelrash Member 211 Member For: 21y 10m 13d Gender: Male Location: Dalby, QLD Posted 13/12/09 08:19 AM Share Posted 13/12/09 08:19 AM sounds like an exhuast manifold leek nah definately not an exhaust leak, its not easy to pick up in the video but its a mechanical tap-tap-tap sound. Link to comment Share on other sites More sharing options...
icer Banned 2,335 Member For: 15y 3m 29d Gender: Male Location: Aspendale, Vic. Posted 13/12/09 08:30 AM Share Posted 13/12/09 08:30 AM since when can you install sprinkler systems in our cars?!?!sounds like a piston/rod to me ;( any white smoke or fluid leaks? Link to comment Share on other sites More sharing options...
HI PSI Member 1,586 Member For: 18y 5m 22d Gender: Male Location: Central Queensland Posted 13/12/09 08:31 AM Share Posted 13/12/09 08:31 AM Dude.. That has gotta suck !!!! At least you haven't pt a leg out of bed like I did... It will be alot cheaper for you to rebuild it without repacing cranks sumps starter motors etc...... I now have a spare engine just in case that it happens again.... Good luck and keep us posted... Link to comment Share on other sites More sharing options...
mattyb Donating Members 1,097 Member For: 16y 5m 2d Gender: Male Location: Gold Coast, QLD Posted 13/12/09 08:35 AM Author Share Posted 13/12/09 08:35 AM the sound in the video is 99% the same as in real life. I'm doing a compression test tomorrow. that'll tell if it's a rod. Link to comment Share on other sites More sharing options...
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