The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 11-27-2011, 03:49 PM   #1
kris's66lwb
resident wrencher
 
Join Date: Dec 2006
Location: ramona california
Posts: 720
Vaccum leak!?

So I replaced my fuel pump the diaphragm tore Or so I thought. At idle it's runs like hell And higher rpm it's fine indicating vacuum leak I covered up the carb mouth and ts still ran anther sign of leak. Crab sprayed the intire intake and all th vac lines no noticeable blip in revs up or down. I checked the modulator. No leak what am I missing help please
Posted via Mobile Device
kris's66lwb is offline   Reply With Quote
Old 11-27-2011, 05:01 PM   #2
ozark
Registered User
 
Join Date: Jan 2008
Location: Eureka Springs AR
Posts: 179
Re: Vaccum leak!?

You'll think I'm crazy. I have found some vac leaks that would not show up by spraying carb cleaner by using a length of 3/8 fuel line like a doctors stethescope. You will be amazed how much the hose will amplify the sound. Just run the end of the hose along the carb and intake anything else that takes vacume while holding the other end to your ear.
ozark is offline   Reply With Quote
Old 11-27-2011, 05:21 PM   #3
kris's66lwb
resident wrencher
 
Join Date: Dec 2006
Location: ramona california
Posts: 720
Re: Vaccum leak!?

Your not crazy iv seen that b4 I guess on Tuesday I'll grab my electronic stehoscope from work it's just a big muff leak. And intermitten too is seems. Like I'll come down from wot. And itll idle fine which is werid seing as how right after letin of wot there the highest vac then itl run like crap for a bit and be fine the plugs are good he wires ok the.Cap and rotor are fine too the diss is new. So I'm ruling out ignition unless ts a coil I'm getting plenty of air flo. So idk If it's not a vac leak
Posted via Mobile Device
kris's66lwb is offline   Reply With Quote
Old 11-27-2011, 06:33 PM   #4
rs72z
Registered User
 
rs72z's Avatar
 
Join Date: Oct 2011
Location: Emory TX
Posts: 900
Re: Vaccum leak!?

Quote:
Originally Posted by kris's66lwb View Post
Your not crazy iv seen that b4 I guess on Tuesday I'll grab my electronic stehoscope from work it's just a big muff leak. And intermitten too is seems. Like I'll come down from wot. And itll idle fine which is werid seing as how right after letin of wot there the highest vac then itl run like crap for a bit and be fine the plugs are good he wires ok the.Cap and rotor are fine too the diss is new. So I'm ruling out ignition unless ts a coil I'm getting plenty of air flo. So idk If it's not a vac leak
Posted via Mobile Device
Is this the same one that in a diffrent thread you said it had gas in the chracoal canister?

If so you need to pull the top of the carb and see if it has any of the charcoal out of the cannister in the carb. I've seen it many times. The charcoal will get in the jets and make it run like crap.
rs72z is offline   Reply With Quote
Old 11-27-2011, 07:16 PM   #5
kris's66lwb
resident wrencher
 
Join Date: Dec 2006
Location: ramona california
Posts: 720
Re: Vaccum leak!?

Ok I'll try that
Posted via Mobile Device
kris's66lwb is offline   Reply With Quote
Old 11-27-2011, 07:59 PM   #6
kris's66lwb
resident wrencher
 
Join Date: Dec 2006
Location: ramona california
Posts: 720
Re: Vaccum leak!?

Checked for charchol noting bit my access pump is all torn to he'll
Posted via Mobile Device
kris's66lwb is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 12:25 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com