The Lotus Cars Community banner

1 - 20 of 35 Posts

·
Registered
Joined
·
57 Posts
Discussion Starter #1
Finished up the Katana install tonight but upon start up I have a hissing sound coming from the opposite side of where the vacuum actuator is mounted. I can cover the hole with my finger and the car idles great, but as soon as I unplug the port the car stumbles. Am I missing something simple?

The air is being sucked in at the port near the firewall on the top side of the blower.
 

·
Premium Member
Joined
·
1,307 Posts
Hi rapsquared. is the hole you are refering to surrounded by 6 threaded holes? If it is then it should have a plug like a freeze plug on the engine block. The bypass valve shaft runs from one side of the supercharger to the other. on one side the actuater is installed. In your case of the Katana it is underneath the blower housing when installed. The other side is I believe what you are refering to. This should have a metal cap. If it does not then you are sucking air under vacuum at idle and leaking boost under throttle. Here is a picture with the cap. Not sure where to source one but I will search.
 

Attachments

·
Premium Member
Joined
·
1,307 Posts
The best bet would be to email magnacharger.com and inquire about a plug for the bypass valve shaft. Not sure what else would work. A block off plate can allways be made with a piece of aluminum or stainless steel and drill the 6 holes and bolt it on with some gasket sealent as that port is not used. The shaft still needs to rotate so filling the hole is not an option. I will research in am for a source. It may very well be a staandard plug.. Turbophil probably would know exactly what this is called. Tommy
 

·
Registered
Joined
·
57 Posts
Discussion Starter #5
Well thats good news, hopefully an easy fix. Ill do some searching as well knowing for sure it should be plugged!
 

·
Premium Member
Joined
·
1,307 Posts
In thinking about it last night, I am usure if there is an internal seal on the bypass valve shaft. The side attached to the actuator has no cap but does not leak. I have never rebuilt a supercharger yet so I am not 100% sure of the internal mechanics of the bypass valve. I will try to call magnuson later. I hope it is just a plug used. Tommy
 

·
Registered
Joined
·
57 Posts
Discussion Starter #7
Just talked to Magnuson and there is a needle bearing that should be keeping that side from leaking as it moves around:(
 

·
Premium Member
Joined
·
1,307 Posts
Will they sell you one or tell you how to get one. I have searched all over and the only bearings I can find are for the front and rear of the rotor assembly not the bypass valve shaft. I imagine you can replace the bearing and there are several rebuild kits out there for the mp62 that include everything. It sucks that it is installed allready but I do not think this could be forseen without seeing it in operation before purchase. Let us know what you do as mybe we all should check for leaks at this location. I certainly never have. Tommy
 

·
Registered
Joined
·
57 Posts
Discussion Starter #9
They said it would require their complete rebuild service. I am wondering if the shaft has enough movement to replace just what needs replaced and then let it slide back in. Maybe sector can shed some light as well
 

·
Premium Member
Joined
·
1,307 Posts
Rick I spoke with Simon at Magnuson and am waiting on a call back from David. It is a closed end caged bearing that is used on that side. From the pic you sent me it looks like the whole bearing came out. Not sure how that happened. It is easy to source closed end bearings but need the dimensions from Magnuson. I will call you when I find out more. Here is a link that explains the type of bearing.
http://www.pibsales.com/pdf/rollerclutch.pdf
 

·
Premium Member
Joined
·
1,307 Posts
Thats great Rex! I hope it works out. When you get the bearing post what size or model number it is for future reference. Tommy
 

·
Premium Member
Joined
·
1,307 Posts
Thank you Rex for posting this info as it will help many in the future! We really are a small community and need to help each other. Its these things that are really important and was what this forum was about 1/2 decade ago. The uberpost is comprised of this type of knowledge! Not political bs that surrounds us. This issue will arise later and someone will be very thankful for your info. Whatever you decide to do there will be people here to help. Tommy


Sent from my Autoguide iPhone app
 

·
Premium Member
Joined
·
1,307 Posts
Post 14 has a link I believe. Unsure if any has changed. Been a while.
 

·
Tire abuser
Joined
·
772 Posts
I just found this thread. Any picture of the bearing cap and the bearing dimensions?
HK,

I have noticed a couple of posts you made today. It looks like you may be having an issues similar to mine. My car thew a code on Sunday that made me think there is an intake leak somewhere. While I was looking for it, I saw that the cap over that bypass valve shaft looked cracked around it's circumference. When I touched it, it stuck to my finger and then fell into the engine compartment somewhere. Well, there is a leak!

Earlier, I ordered a rebuild kit from Ebay. I plan to go through the whole SC and check it out. I have sent them a message asking specifically about that bearing and will let you know what I hear back.

Magnuson supercharger Complete Rebuild Kit SKF MP62 MP90 Eaton | eBay
 

Attachments

·
Registered
Joined
·
6,222 Posts
Some how the car has Vac Leak, but can't find it, we more than trible check all the hose, gasket & O rings. So tmr will try to check out this area.
 

·
Tire abuser
Joined
·
772 Posts
1 - 20 of 35 Posts
Top