Hi guys, possibly a question for any one with a mechanical knowledge. I have a ST 162, sweet as, it drives real well, but get to 3000 rpm and there is a noticable vibration. not a bad one just constant one that you can feel on panels and hear through to around 3500 rpm. any idea on the cause ? could it be a timing belt. or something like that ? when cruising last nite on new smooth section of freeway it gave me a good chance to hear it better when it started, I originally thought it was the exhaust covers rattling, so I removed them. when it starts, it vibrates the windscreen interior edge panels too, other than that, it's as smooth as under 3000 rpm. over 4000 rpm it's probably still there but it's lost with all the engine and exhaust sounds.
hmmm, could be either side engine mount , or could be any , does it change if you put your foot flat , or just ease the accelerator up , aka cruise along
You need to try and isolate the vibration. Try driving at 3000rpm and note the KPH you are going, then drop it down a gear but keep the same KPH. If the vibration is still there it is most likely drivetrain related as you have not changed the speed the half shafts are revolving at. If the vibration goes away then it is most likely engine / engine mounts. You can also try getting the car up to 3500 - 4000 rpm and then take your foot off the gas and press in the clutch and let it coast and see when the vibration goes away. If it goes away as soon as you press the clutch then it is probably engine / engine mount related. If the vibration remains as you coast it is probably drivetrain related.
check your wheel weights. ive lost one an it becomes a terrible vibration because the wheel is off balance now. My passenger wheel is still missing it, but it is a bearable vibration.
I've had this problem with previous car. I found that my tire was flat/going flat. I would wait for it to happen and then hit the gas station and fill it back up.
if it's just rpm based, like it does it without moving, then i would check the mounts and if they are all fine it's time to check the rods.
ok, thanks guys I do appreciate your help on this, I gotto solve it ! well I have tried just sitting in neutral and lifting rpm slowly to 3000rpm then it starts, it happens in each gear when driving at or around 3000rpm at 3000rpm in 5th gear it's going about 100kph, when I hit the clutch or put in neutral and coast it seems to stop. as I said any speed in any gear lower than 3000 rpm is smooth as ? the vibration is not severe just like (this is going to appear stupid,) going vvrrrrrrr through your lips, if that makes sense ? how do I check the mounts ? what do you mean check the rods ? tyres are all new and balanced, I know what an unbalanced wheel feels like and it's not that. could it be a timing belt as it could be due for a change ? engine revs freely through to high revs but with vibration over 3000rpm
don't freak out about this but i do know the problem. you have a worn rod bearing or wrist pin. my fe motor did this and it lasted 100K miles before it threw the rod.
mafix, thanks are you sure? how do I fix it, how do I tell which one it is ? is it expensive to fix if it is that? what do you recommend ? how can I check your idea of wat it is , to be sure before dismantling anything ? thanks
your motor should not be even running at 500 rpm idle should be set at 800-850 rpm shaking @ 500rpm probably 'cose it's about to stall ??? hehe !
yeah, but this is a 3GSE motor, Any other suggestions please, not liking the idea of having to break the engine down ! drives real nice if I'm under 3000 rpm, maybe I'll just drive it like Grandpa ? hehe it looks like it going fast, as all ST162 do anyway ! how do I check the mounts, when I had some work done recently on the front end bushes etc the guy said my mounts (except the very front one which was sagging a bit ) were fine. could it be this one that's the worrie ?
I have a similar situation with my HalfTrac...I was told it is the engine mounts. Getting 1-2 or even all new ones should fix your noise. A car being that old could probably use all new ones IMO. They do cost a pretty penny though. Anywho, hope that helps.
The front mount should be the 1 with the yellow arrow. you should be able to see it just by opening the hood. The center rubber piece with the metal tube in it likes to crack in the areas indicated by the yellow lines so really you just want to make sure that the rubber is in good shape
