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TR2/3/3A TR3B Vacuum Line Route

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af3683

af3683

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I would appreciate it if anyone could please post a few photos or provide an explanation of the proper route for the TR3B vacuum line going from the distributor to the front carburetor. My vacuum line currently goes underneath the thermostat housing/hose but is a bit too close to the fan belt for my liking. It also has numerous bends in it from prior owners and may not be providing adequate vacuum. I'm thinking of replacing it and would like to make sure I route it the proper way. Based on my research it looks like some also route the vacuum line over the thermostat housing or between the thermostat housing and the valve cover. The TR3B vacuum line may also route a bit different that the TR3/A. Any help would be appreciated. Thanks.
Art
 
It should be the same as the 3a. There’s a clip on the front of the thermostat housing that holds the vacuum line and the fuel line “more firmly” above the fan belt. Hope these pics help. There is also a rubber bushing that holds both lines in the clip (Moss 680-755)
 

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Thank you very much. I don't seem to have that clip on the front of the thermostat housing that holds the vacuum line and the fuel line. Also, my fuel line is located in the space between the thermostat housing and the valve cover. Not sure if this was a change made with the TR3B/TR4.
 
My engine is a TR4 (CT…) and has the clip but my car is a bit of a frankenCar and have a TR4 thermostat housing and probe. BTW that red sheath is a flexible heat shield covering my fuel line from the pump to the carb and between the carbs.

The Moss or Rimmer diagrams are usually my baseline of what should be where.
 
There are at least 2 different clips that I have seen on TR3&4s. Both of them run the fuel line and the vacuum line under the thermostat housing.
Attached pics are of an original clip shown on 1/4" graph paper, in case you want to make your own.
Then the same type clip with the rubber insert for the 2 lines ( on a TR4).
And the second type which is on a TR3A is best described as a hanger that has a full circle ( about 1" in diameter) that the 2 pipes fit through.

The first type with the insert is the best type. But they both function to keep the 2 lines away from the fan belt and moving parts.
Charley
 

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