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What's the vacuum boos. hose connected to? A Pic?

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When I start my car and she finally idles nicely. I get the old cartoon submarine burbling.
It is loud. It is embarrasing.
Sounds at times like the Yellow Submarine from the Beatles cartoon.
Prior owner is adament that when he installed a new alternator he must of somehow pushed the hose off from the V.B.
Could someone post a pic. Where this hose goes?
Working one step at a time and very slowly.
Lost some momemtum. Due to the angels have been busy elsewhere.
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· Wingless Wonder
1988 Esprit Turbo, 2005 Elise BOE Supercharged
7,019 Posts
The stock, OE mechanical vacuum pump has one vacuum - source inlet, and one outlet.

With the engine undertray removed, you can see the inlet hose. That one comes off towards the center of the chassis. A main hose runs up front to the booster for the brakes, and there is a tee that provides a smaller vacuum source for the heater controls and emissions equipment like the EBPV and throttle jack for the A/C. You can see all that with the undertray removed.

It is a normal thing for the vacuum pumps to get noisy with age as you describe. That doesn't mean they are no longer effective, just noisy.

You can muffle the pump noise by installing a small filter (like a fuel filter) on the outlet end of the vacuum pump hose, which is cable tied to the LH lower frame tube and ends under the transmission. I ran with a filter for 12 years without incident (or noise).

If you decide that you want to replace the vacuum pump, the new one will probably not have an "exhaust" outlet fitting, so the hose that Lotus used (and filter) is not needed.

Here's the vacuum tee, looking towards the front:

Here's a pic of my white "silencer":


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