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#61351 06/06/2006 1:45 AM | Joined: Aug 2005 Posts: 183 Wrench Fetcher | | Wrench Fetcher Joined: Aug 2005 Posts: 183 | I did a tune-up on my truck today and everything went pretty-good. We got to the vaccuum test but there was no vaccuum suction from the carb. I asked my dad what to do and he suggested I use q-tips to clean the opening and a copper wire to remove the blockage. I did that and still no vaccuum. So, now what do I do? Should I use the compressor and blow it out or do I need a new carb?
I'm still shooting for passing Aircare (emmission testing) in 2 weeks. How does no vaccuum affect the engine? I don't really understand how it works. The engine runs great but when we reduced the rpm to 475 in the manual it was not too happy so we put it back to 600 for now. | | |
#61352 06/06/2006 2:04 AM | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | I would not reccomend blowing it out, you may damage the carb internally. Instead, get an overhaul kit and dissasemblr the carb. that way you can inspect and clean it more thougholy. Also get a paint gun cleaning kit. These come with an assortment of small brushes(like a mini rifle brush) that can be used to clean the passeges more efficiently. Get a few cans of carb cleaner too, some parts houses and farm stores have it in quart containers as well as spray cans if you need to soak it. It sounds like you may have carbon buikdup in the throttle plate housing, that woud be a good place to start.
Bill Burmeister
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#61353 06/06/2006 3:52 AM | Joined: Mar 2004 Posts: 3,068 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 3,068 | Are you testing a manifold vacuum port or a ported vacuum port. Next time you hook up, see if you get any vacuum above idle,
Scott | | |
#61354 06/06/2006 6:11 AM | Joined: Aug 2005 Posts: 183 Wrench Fetcher | | Wrench Fetcher Joined: Aug 2005 Posts: 183 | In the shop manual they call it a "vacuum port on carburetor" which is located below the idle mixture screw "A". I thought there would be a vacuum reading at idle - the manual mentions it. Instead we got nothing. I didn't think to rev it a bit.
Longbox55 - thanks for the recommendations - swapmeet on Saturday so I know what to look for. | | |
#61355 06/06/2006 9:38 AM | Joined: Feb 2005 Posts: 469 Shop Shark | | Shop Shark Joined: Feb 2005 Posts: 469 | Do you have the right gasket between the carb and manifod? If it's a inline six the gasket should have two vacuum holes in it. | | |
#61356 06/06/2006 9:47 AM | Joined: Apr 2005 Posts: 641 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 641 | yes look at your mount gaskets they do have holes and can be mounted back wards or filled in with gasket sealer | | |
#61357 06/07/2006 6:04 AM | Joined: Aug 2005 Posts: 183 Wrench Fetcher | | Wrench Fetcher Joined: Aug 2005 Posts: 183 | So my next step would be to remove the carb and review the gasket? What happens if that all checks out ok?
Please excuse my ignorance - this was my first ever tune-up. The overhaul kit for the carb sounds like a good idea...or is it? So use the carb cleaner on the manifold side of the vacuum thing or only on the carb side of it?
Thanks everyone for your help & guidance! Appreciated! | | |
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