ON THE RADIATOR FAN SHROUD Purchase a Haynes Manual from a parts house or bookstore. The investment will be well worth it as they make them for specific cars.
There should be a diagram of the vacuum lines on the passenger side shock tower.
You can find a 1986 Winnebago, with the Chevrolet 454 cubic engine, vacuum routing diagram at most Chevrolet dealerships. The vacuum routing diagram can also be found in most Chevrolet engine service manuals.
You can find the 1986 Chevrolet vacuum line diagram at most Chevrolet dealerships. The vacuum line diagram can also be found at most auto-parts stores.
the diagram you are looking for is on the fan guard connected to your radiator
Chiltons service manual
usually there is i sticker on the core support showing the vacuum diagram. If its not there then i would spend 20 bucks on a chiltons manual.
There should be a diagram of the vacuum lines on the passenger side shock tower.
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look on eBay for 1986 Nissan service manual
there should be one on a decal under the hood. otherwise look in the apropriate copy of "motor manual" or "chilton's" or a factory manual
The Chiltons/Haynes 72300 has the vacuum circuits divided into the emissions, Fuel and brakes sections of their manual covering each vacuum hose.
A local Ford dealer should be able to supply the needed diagrams for the vacuum system of 1986 Ford 351. They keep these items on hand or know where to find them.