Refer to thread: http://ferrarichat.com/forum/showthread.php?t=193230 I updated the title for anybody doing a search in the future. Today I finally got to replacing the by-pass valves. Thanks 91TR for your help! After removing the front bypass valve, I tested it and it was leaking, always open. You should be able to blow in only one direction, mine was rusty, dirty and I was able to blow air in both directions. I did not attempt to clean it. The GM parts dealer recognized the bypass valve, but the thread did not match. The bypass in our Ferrari's are for early 80s GMs, The GM dealer I went to only carried parts from 1997 on. Napa, Kragen and PepBoys did not have the part in stock. Carquest had only two in stock, so I took them. The tube for the hose is slightly smaller than the original, but the clamp secures the hose tightly. These are the parts I bought, for the record. Valve Part number EC AV7. For the 90 deg bend hose, I used a water hose part number 28474 Fuel emissions hose part number 27010 For the clamps I used part number CHC 1012 Total cost: $60.63, including taxes. When installing the valves, I applied anti-seize to the thread. The rear valve was a pain to remove and reattach. The water hose I bought may not last as long, but it is in a relatively easy place to access. Carquest does not have fuel rated hoses wiht a 90 deg bend. The car now sounds great. It still has a small leak in the rear header that dispears when the engine is warm. Again, thanks 91TR! Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
I replaced mine a few months ago. Here are some pics of the old one. Image Unavailable, Please Login Image Unavailable, Please Login
Glad you got it sorted (and at reasonable cost ) Richard. Your model (with the pulse type air injection) is actually much harder on the check valves since they have to back seal hot exhaust gases continously during warm running -- on the earlier models, with a continuously running air pump, the check valves get better cooling during warm running and last a little longer. Joshua -- the part you show is actually the vacuum controlled cut-off valve, but your failure was also caused by bad check valves letting hot exhaust gas go back upstream and melt your (plastic) cut-off valve -- which just shows why it's important to have good check valves in place.
Richard, The part number is 147390 and is available at ricambiamerica: http://www.ricambiamerica.com/advanced_search_result.php?keywords=47390&osCsid=a9ff5a4ba1735d2e5d6bf5c38f646c17&x=0&y=0 Regards, Josh Ferguson
The Ferrari part is $80, the AC Delco, Walker and BWA are about $7, but I can't find them on-line. I'll try the parts store during the week. Here is a thread talking about the cross ref part numbers: http://ferrarichat.com/forum/showthread.php?t=142985&highlight=147390 I love this list! Cheers,
