"Knocking" on start-up??

944S Boyeee · 02-07-2002, 06:12 AM

Just had the car out for a spin (couldn't wait till summer) and noticed something I also noticed when starting the car prior to storing it. When the car is first started (when it was cold out), I can hear a "knocking" sound. It sounds like it's coming from the front of the engine. It only does it for about 2-3 minutes, till it warms up. It sounds like a "thumping" sound that could be air, but it is also "solid" enough that it could be something else.

Any suggestions as to what this might be???

944S Boyeee · 02-07-2002, 06:14 AM

Oh - by the way - the belts and water pump were done at 96,000 KLMS and the car now has 124,000 KLMS, a difference of about 30,000 KLMS, which is about 17-19,000 miles.

Roger Hall · 02-07-2002, 05:25 PM

probably just the mouse that crawled up into the engine and is now spinning aroud the alternator belt just kidding

engines can make strange sounds when sitting for awhile even if you dont drive it you should start it once a month start the engine and if the noise goes away change the oil and just drive it easy for awile and let me know if the noise returns

RaF944 · 02-07-2002, 05:34 PM

you shouldnt worry about it unless its a loud sound or an oil starving sound.... Did you check your oil?

Mine made a weird noise when it sat for 2 weeks but after that it went back to normal in about a minute.

mlue · 06:58 PM

Quote:

Originally posted by 944S Boyeee
Oh - by the way - the belts and water pump were done at 96,000 KLMS and the car now has 124,000 KLMS, a difference of about 30,000 KLMS, which is about 17-19,000 miles.

You could be getting some belt slap if the belt is too loose, it may be due for a retension. These engines shrink when they are cold and expand as they warm up, so if your belt is in need of tensioning, this causes the belt to slap against the timing belt cover or the cam gear cover until the engine warms up and the excess slack is taken up. Easy to check by starting the engine and putting you hand on the timing belt cover or if you remove the cover you will see the belt bouncing around.

Check this out: http://boerger.golden-tech.com/images/tbelts.html

Mark
'86 944NA

slevy951 · 02-08-2002, 06:21 AM

Could it be you have a lifter that isn't pumping up on startup?

944S Boyeee · 02-08-2002, 06:33 AM

If the lifter thing is the case - what else is going to happen I should look for??? Or how do I fix it???

slevy951 · 02-08-2002, 07:58 AM

How old is your oil? You may try changing the oil. Or there may be some crud that is stuck in the lifter. Or the lifter is just bad.

ch944 · 02-08-2002, 08:22 AM

A stuck lifter will give you more of a ticking sound, like the injectors but louder. Boyeee, are you anywhere near Shelburn? I think I spelled it right.

ch944

944S Boyeee · 02-08-2002, 11:43 AM

Thanks - the oil was changed about 5000KLMS ago (around 3000 miles). It is more of a knocking sound that seems to be coming from the rad area. Would belts that need re-tensioning cause this sound?? Like I said, it only does it when the car is cold.

Ch944 - I live not to far from Shelburne. Pretty much any place in my Province isn't that far away from me, as I live "in the middle". I think Shelburne is about an hour and a half away from me, maybe less.

ch944 · 02-08-2002, 12:00 PM

The reason I ask is I have a ship ( Green Reefer Lines) 10' off my office window and we r unloading it now. It came for Shelburne yesterday. Small world man.

ch944

944S Boyeee · 02-08-2002, 12:06 PM

It is a small world - I noticed you live in New Bedford. Oddly enough, the next town over from me is Bedford. Founded in 1712, so I'm not sure if it's the Original Bedford inwhich your hometown was named or if it's just that there are a lot of Bedfords around (?). Still cool that you live in a town that is similar in name to a town next to me and you have a ship not 10' from you that came from a place very close to my hometown. Very small world.