coldhammer said:
Check the "spider" (star looking bushing between the blower and drive shaft) as that is a maintenance item and is prone to wear and tear.
Armando
Finding a boost leak.
- Thread starter coldhammer
- Start date
Check the "spider" (star looking bushing between the blower and drive shaft) as that is a maintenance item and is prone to wear and tear.
Armando
What am I looking for in the spider?
coldhammer said:
Wear, some "gear lash" is normal, but if the spider is wore it might increase the sound. I would also check to see if the set bolt that holds the gear to the blower is on tight.
Armando
Hi guys just a quick idea I thought of today for finding a leak in a pressurized system. When doing construction with my dad the plumbing system in a house must pass a 5 psi pressurized test with no leaks for 15 minutes. The last house we built had a stubborn leak that we could not find. My dad found an electronic leak detector online. It consisted of a set of headphones connected to small box with a tube on the front setup to amplify high frequency sounds. it has a gain adjustment and also a volume control. we would just walk around the house putting the device close to all of the plastic pipe joints until we could hear the leak. It works really well, we found the leak in a few minutes. I will try to get the info on the device tonight. I think it cost about $125.
Well sometimes my stupidity amazes even myself. The noise was being caused by the pulley not being securely fastened to the drive shaft. I had forgotten to put the washer back over the pulley bolt. So that imediately fixed the noise problem.
Now its back to the boost problem. I had pulled off the pipe connecting the sc to the tb. Because I didnt have any couplers I replaced it. I drove the car to orlando last weekend and it was making 7 psi instead of the 5psi prior to removing and replacing the aluminum elbow.
Naturally I thought the problem was that i had a leak around the elbow somewhere and that the reason for 7psi instead of 8 psi was because i needed to replace the set screw on the paxton.
So i have replaced the set screw and put the elbow back on but alas I am only making 5.5 psi max. I have sprayed soapy water over all the connections and parts and there are no air bubbles forming. So I can not see that I have a leak anywhere. My mechanic orignally wanted to do a leak down test to check the pistons. However if I am leaking air around the pistons would that allow for fluctuating boost levels?
I am more inclined to believe i still have a leak somewhere. At this point thought the only other place I could think of would be if the BOV that comes with the kit is not working properly.
SO my two questions are
1) is there a way to test the plastic bov to see if its working properly.
2) Could a compression leak from the pistons allow the boost to run at 5psi one day and 7 psi the next?
Now its back to the boost problem. I had pulled off the pipe connecting the sc to the tb. Because I didnt have any couplers I replaced it. I drove the car to orlando last weekend and it was making 7 psi instead of the 5psi prior to removing and replacing the aluminum elbow.
Naturally I thought the problem was that i had a leak around the elbow somewhere and that the reason for 7psi instead of 8 psi was because i needed to replace the set screw on the paxton.
So i have replaced the set screw and put the elbow back on but alas I am only making 5.5 psi max. I have sprayed soapy water over all the connections and parts and there are no air bubbles forming. So I can not see that I have a leak anywhere. My mechanic orignally wanted to do a leak down test to check the pistons. However if I am leaking air around the pistons would that allow for fluctuating boost levels?
I am more inclined to believe i still have a leak somewhere. At this point thought the only other place I could think of would be if the BOV that comes with the kit is not working properly.
SO my two questions are
1) is there a way to test the plastic bov to see if its working properly.
2) Could a compression leak from the pistons allow the boost to run at 5psi one day and 7 psi the next?
Loose belt will also cause less boost.
Armando
Armando
I dont think the belt is loose. I have it so tight its starting to bend the little bracket on the altenator. Cant get it any tighter.
Yellow Rose
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coldhammer said:
1 - Yes. With a hand-held vacuum pump, you can reverse the tubing so that it applies pressure instead of vacuum. The gauge on the pump will show at what pressure the boost divert valve opens. These vacuum pumps are sold at auto parts stores for approximately $25.
2 - You are contradicting yourself......how can a compression leak result in more boost?
Having it that tight will cause you major problems in the form of an engine bearing failing on you. You shouldn't need that belt that tightcoldhammer said:
So after talking to MB today we came to the realization that someone had put the bypass valve on backwards. So that solved the bypass valve issue.
I asked the question about the compression leak because I don’t know. I was pretty sure that a compression leak would not allow for boost levels to vary but then I have been wrong about things that I was pretty sure of in the past. Thus I asked a question.
I had already eased up the tension on the pulley belt so engine bearing wear shouldn’t be an issue.
After correcting the direction of the bypass valve I did a run and logged it on the AEM. The AEM showed boost was up from 5.5 to 6.3. Still not 8 psi but a definite improvement.
I then tried fiddling with the elbow again to make it a tighter fit and made some more runs. My first run produced only 4.5 psi in 1st gear. I decided on a whim to go someplace where I could run it all the way through second gear. This time I made 7.5psi in first and got up to 7psi in second gear before the elbow popped off the volute. This is extremely strange to me as all I did was drive for about 15 minutes then made the second run. I did not touch anything.
The other odd thing I noticed is that during several of my runs my boost gauge showed 8psi while the AEM only showed 4-6 psi. I have heard that there is a discrepancy between what the AEM and a boost gauge will read. But that is a rather large discrepancy.
Any thoughts?
I asked the question about the compression leak because I don’t know. I was pretty sure that a compression leak would not allow for boost levels to vary but then I have been wrong about things that I was pretty sure of in the past. Thus I asked a question.
I had already eased up the tension on the pulley belt so engine bearing wear shouldn’t be an issue.
After correcting the direction of the bypass valve I did a run and logged it on the AEM. The AEM showed boost was up from 5.5 to 6.3. Still not 8 psi but a definite improvement.
I then tried fiddling with the elbow again to make it a tighter fit and made some more runs. My first run produced only 4.5 psi in 1st gear. I decided on a whim to go someplace where I could run it all the way through second gear. This time I made 7.5psi in first and got up to 7psi in second gear before the elbow popped off the volute. This is extremely strange to me as all I did was drive for about 15 minutes then made the second run. I did not touch anything.
The other odd thing I noticed is that during several of my runs my boost gauge showed 8psi while the AEM only showed 4-6 psi. I have heard that there is a discrepancy between what the AEM and a boost gauge will read. But that is a rather large discrepancy.
Any thoughts?
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