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sf49er

Hi all!

My '90 1.7 ie has started making a whistling noise. It's the vacuum tubing from the inlet manifold which ends in the fuel fumes carbon canister. At idle it's vibrating and I wonder if there is an easier fix than removing the cannister itself, which involves removing the wheel well lining.

Curiously enough I had the same noise gradually occurring in the last 3:rd gen 33 I had. Never bothered to troubleshoot it, however, since I knew I wasn't going to keep the car. This one, however, is a keeper and thus I need to silence it Smile

Suggestions?
_________________
Bo M. Hasselblad
Linkoping, Sweden
Secretary of Club Alfa Romeo Svezia
sekreterare@alfaromeo.org

gritsop · Posted: Sun May 27, 2012 6:11 pm Post subject:

Check to see the carbon canister valve which is under the coolant expansion tank.

It is a valve in orange color having 3 ports. From memory two are going to the distributor/intake manifold and one to the canister.
_________________
Thanassis Gritsopoulos
1991 Alfa 33 1.4 IE
2001 Alfa 147 1.6 Distinctive

http://www.alfa-restoration.co.uk
Parts Shop: www.alfa-restoration.co.uk/shop

sf49er · Posted: Tue Jun 12, 2012 11:44 am Post subject:

Thanks for the suggestion!

I found the valve (mine is partly orange and mostly black) and took it out. It apparently closes the connection between the cannister and inlet manifold when there is low or no vacuum on the "control" pipe that also connects to the manifold. When applying suction on the control connection it clicks and the vapour suction is closed when at rest. No leakage through the valve that I could find. I'll connect the two vapour tubes with a straight pipe to by-pass the valve to see if the noise disappears.

Otherwise, is there anything else I could do with the valve, other than clean the outside. It seems to be a sealed unit so can't dismantle it clean.
_________________
Bo M. Hasselblad
Linkoping, Sweden
Secretary of Club Alfa Romeo Svezia
sekreterare@alfaromeo.org

sf49er · Posted: Tue Jun 12, 2012 4:44 pm Post subject:

Took the valve out and connected the outlet from the canister with the corresponding inlet to the manifold and the noise is gone. Thus, obviously it is the valve that's the culprit. The question then remains, what do I do with it to make it work properly. It's no longer available according to ePER.
_________________
Bo M. Hasselblad
Linkoping, Sweden
Secretary of Club Alfa Romeo Svezia
sekreterare@alfaromeo.org

gritsop · Posted: Tue Jun 12, 2012 6:44 pm Post subject:

You are right the valve is out of production.

The valve is nothing more than a spring and a rubber membrane ... the membrane is torn apart so that why the valve whistles.

I suggest try eBay or Diffata brother in the USA. I had contacted them some months ago when I needed one and I recall them having an Alfa 75 breaking for spares with a valve like that.

http://www.difatta.com/

Regards
_________________
Thanassis Gritsopoulos
1991 Alfa 33 1.4 IE
2001 Alfa 147 1.6 Distinctive

http://www.alfa-restoration.co.uk
Parts Shop: www.alfa-restoration.co.uk/shop

sf49er · Posted: Tue Jun 12, 2012 10:27 pm Post subject:

I'll see if we may have a club member who has one and is willing to part with it. There are quite a few with both 33's and 75's so I may be lucky!
_________________
Bo M. Hasselblad
Linkoping, Sweden
Secretary of Club Alfa Romeo Svezia
sekreterare@alfaromeo.org

gritsop · Posted: Tue Jun 12, 2012 10:48 pm Post subject:

Hi

My 33 in its 21 years life span is on its 4th valve. Thats why it is good to have a pile of parts ready for any occasion.

Regards
_________________
Thanassis Gritsopoulos
1991 Alfa 33 1.4 IE
2001 Alfa 147 1.6 Distinctive

http://www.alfa-restoration.co.uk
Parts Shop: www.alfa-restoration.co.uk/shop