[richardbradford]

Hi,

For the first 30 seconds or so after morning first start there is an intermittent impact 'bang' from the belt side of the engine. It's not regular and clears after the short period but is quite heavy.
Suspect the power steering pump, it moves at least 1cm in-out on its axis but not sure and going to have a closer look tomorrow. More nastily it could be something in one of the heads or on the cambelt but if there would have expected it to be more regular.

Any ideas?

Richard

Alfa 164 Super 3.0 24V

PS. The water pump is also suspect.

 

[goats]

pull the pass tire, fender liner, and remove the serp belt. Then start the car and see if it happens. Banging is not good typically -- I can not imagine a Power steering pump with 1 cm axial play -- how is this possible?

 

[eric_h]

"Banging is not typically good"...amen to that!

Richard, is it *only* on cold starts with no sounds at all when started warm? Perhaps you could have someone else start the car while you listen from up front.

Does the engine idle roughly after a cold start? How old are the motor mounts?

 

[richardbradford]

Thanks guys.

1cm might be an exageration but it is not far off.

It only seems to happen on the first start after a cooler night. Idle is fine. Power is fine. Clears after 30 seconds or so and doesn't seem to return for the rest of the day.

First started a month ago and from inside sounded like driving over a loose manhole cover. Only noticed it as something else as started with window open today.

Potentially could be something sticking internally (valve maybe?) as slight 'butter' colletion inside oil filler from short journeys - suspect slight head-gasket weep. Going to gve it an oil change tomorrow - use Magnatec 10w/40 and have done for last 10 years.

 

[richardbradford]

Don't think its an engine mount issue.

Thanks.

 

[144]

With the engine off rock the engine fore and aft as hard as you can. Look at the dogbone mount and see if it's loose.

 

[richardbradford]

Hi,

engine mounts fine, thanks.

As it only happens at first morning start on cool days it must somehow be temperature related. 95% definite not happening after first minute of running as loud enough to hear it from driving seat when does. There is at least a 3 second gap between the bangs, which is also odd with the engine idling about 1,000 rpm.

Maybe the oil change I'm giving it today will make a difference? Apart from power steering pump or one of the other ancilliaries playing up it must be engine based - maybe a sticking/gummy valve of something like that?

Any ideas?

 

[Alfisto Steve]

The 24v engine does have oil fed hydraulic valve tappets now whether your noise is from one of them that needs to pump up on cold start who knows?

 

[richardbradford]

pull the pass tire, fender liner, and remove the serp belt. Then start the car and see if it happens. Banging is not good typically -- I can not imagine a Power steering pump with 1 cm axial play -- how is this possible?

Hi,

took the serpentine belt off this morning before the cars first start. No bangs/thunks.
Pulled/pushed on power steering pulley and it made the same kind of banging sound I've been hearing. Think the axial play is so great it becomes an intermittent impact issue as it turns. Would explain why the bangs are not regular.
Ironically, put the belt back on and still no banging, last night was warmer than the night before, but am now confident it is power steering pump issue not engine issue - which is nice

Thanks to you and everyone,

Richard