Vacuum Pump
Thread Starter
Racer
Joined: Aug 2012
Posts: 424
Likes: 3
From: Presently working under contract in Alabama
Hey Jer...........
I sure wish I had more time before your car was picked up for it's journey to it's new home, I could have checked out your vacuum system for you.
IMHO, are we sure the messed up hose routing has been corrected, the relay has been tested for proper function, and you're getting good control vacuum from the switches? I would like to see the results of these issues before I would even think about a separate pump. A decent hand vacuum pump tester is much less than more drastic measures.
If you would like, I can talk you through these, and get you a routing diagram if you don't already have one. Let me know........
Good luck my friend!
I sure wish I had more time before your car was picked up for it's journey to it's new home, I could have checked out your vacuum system for you.
IMHO, are we sure the messed up hose routing has been corrected, the relay has been tested for proper function, and you're getting good control vacuum from the switches? I would like to see the results of these issues before I would even think about a separate pump. A decent hand vacuum pump tester is much less than more drastic measures.
If you would like, I can talk you through these, and get you a routing diagram if you don't already have one. Let me know........
Good luck my friend!
I appreciate everything you did for me with this purchase. It is hard to find all these gremlins.
You remember way back when I bought the car. I drove it around the block and to the shop the next morning. I took it there to address this very issue. I decided to have it gone threw and address the years of neglected maintenance. The shop does restoration work, but they are far from Corvette specialists. They are working on the car in their spare time.
I printed out diagrams for them, but I am not sure that they have checked everything. The owner said that he spoke to another Vette owner with a big cammed engine and he had to add a vacuum pump. I have been going through Willcox and the net to get as much trouble shooting info I can find.
I am hoping to bury them with tech information on Monday to make sure that everything has been checked before I have to buy and add a pump.
http://www.corvette-101.com/vacuum.htm#hoses
http://forums.corvetteforum.com/c3-t...tem-works.html
Melting Slicks
Joined: Aug 2012
Posts: 2,548
Likes: 379
From: Woodinville WA
Yes, i would more think you have a leak instead of blaming your cam.
Your mechanic is a little questionable also recommending an unorthodox solution by suggesting installing a big ugly loud vacumm pump, instead of doing diligent troubleshooting and finding a cracked hose.
put a gauge on your canister tank and do a leakdown test after shutting off your engine.. after plugging the appropriate lines.
what else is there besides electric pumps? some hideous belt driven thing?
Your mechanic is a little questionable also recommending an unorthodox solution by suggesting installing a big ugly loud vacumm pump, instead of doing diligent troubleshooting and finding a cracked hose.
put a gauge on your canister tank and do a leakdown test after shutting off your engine.. after plugging the appropriate lines.
what else is there besides electric pumps? some hideous belt driven thing?
I have an air compressor one - never used it until my C3, it was sooooo easy finding the leak that was preventing my lights from lifting.
and I still have trouble with vacuum and have a canister - but you're right, make sure it's not a 1.00 hose needed rather than a $50.00 canister and a $130.00 pump
Pro
Joined: Jul 2010
Posts: 691
Likes: 25
From: Boynton Beach Florida
I bought an electric pump off eBay that is identical to the one sold by Comp Cams and it works great. I tried the canister but didn't notice any improvement. My engine makes 5-7" vacuum.
The pump makes 25" then shuts off and when it drops to 20" or so it turns on again. I put a second vacuum gauge on the pump since I run it solely to my brake booster and let engine vacuum handle PCV and headlights with no problems at all.
Lights really don't need a ton of vacuum provided all the components are working correctly without any leaks as others have mentioned.
The pump makes 25" then shuts off and when it drops to 20" or so it turns on again. I put a second vacuum gauge on the pump since I run it solely to my brake booster and let engine vacuum handle PCV and headlights with no problems at all.
Lights really don't need a ton of vacuum provided all the components are working correctly without any leaks as others have mentioned.
