96 TA

my vented opti's large check valve is clogged and needs replacement. The smaller one works fine but I can hardly get any air threw the larger one. Is there a part number for it or a popular replacement part for it? Thanks

Locruid

Can a optispark vacuum harness be made with parts from local autoparts store? - Corvette Forum


Look about the 4th one down. Otherwise only thing I know is ordering the complete line setup for $70.

Injuneer

The smaller valve it the check valve. The larger valve is a filter and flow reducer

http://shbox.com/1/opti_vacuum_hose.jpg

divineprime

I just want to make sure this is corrected. I dont want to be confrontational for my first post but it looks like Injuneer has the two backwards. The larger one is the one way check valve and the smaller one is the orifice filter. Nice pic though. lol See the youtube video of the buick LT1 breakdown of the ventilation system at about 10:00 minutes in: [autostream]http://autostream.com/camaroz28/?page_type=firebirdplayerthumbnail&framepage=200&t ransactionid=1362892346-711812145&posted_by=divineprime_www.camaroz28.com& youtube_video_id=lFCjaz6zHfc[/autostream]

I actually found a universal checkvalve in a blister pack for 5 bucks and it looks identical to the large one in question.

shoebox

That would be my fault and not Injuneer's. It's my pic. It will be edited. However, there is some discrepancy over what is said in that video and what the descriptions are in the factory manual. They don't agree on which is the filter. I am going to label them as the factory manual shows. You may have to refresh your browser page to see the new pic.

divineprime

Okay so you've found that the factory manual has a misprint. I already told you the big one is the check valve. Remove it and blow through it, it only goes one way. Ahha now you agree! The other smaller one is open flow with filter in it. Simply an orifice. No sense in perpetuating a mistake.

shoebox

That comes off as a little strong from someone I don't know, but I am all about the correct info. The factory manual did say the big one was a check valve (but also filter) and the little one a check valve once again. Surely two check valves are not needed. The video is probably correct.

divineprime

No worries didn't mean it that way. In that post I mentioned to the original poster that you can get them in a blister pack, wasn't sure if you read that. I'm sure you sat there thinking wait a minute I could swear... On that note they probably are partially right. I think the checkvalve upstream should have a pre-filter so it doesn't get clogged and lead to distributor damage or malfuct. The smaller one obviously appears to reduce the flow and looks like a basic emmissions filter to me. I am not breaking mine apart just yet to find out though, lol. I suppose we could remove the small one and verify it as a check valve also, that way we can all be sure about the correct info. Hey come to think of it the original poster wanted a part number anyways.

divineprime

I finally confirmed they both provide the check valve operation. Since the distributor is sensitive to vacuum I recommended replacing the entire unit as an OEM assembly.