[Laust]

I can think of 3 reasons why the factory wound have installed the recirculation feature with a restrictor:

1. Reducing the fuel pressure (if the OE fuel pump produced a higher pressure than the carburetors are designed for).
2. Reducing the fuel temperature in the fuel lines, which have the following effects:
a. Reducing the risk of vapor locks.
b. Lowering the evaporative emissions from the carburetors.

Laust

 

[Laust]

Unfortunately I saw this (fuel tank connecting hose removal and installation) too late, but here is what I have recommended previously and since tried both in my Jalpa and in a Urraco:

It consists of:
1. Join the new hose to the old hose by drilling 4 to 6 transverse holes near the ends of both the old and new hoses and then thread either a nylon or steel wire through those holes.
2. Spray the installed hose through the available holes (if needed make new holes) with a lubricant (silicone, WD40, etc.)
3. Then “just” pull hard and persistently on the old hose, while a helper pushes at the other end.

The most difficult part is to get the old hose to move in the beginning, as it has conformed to the sharp turns in the conduit section.

Attached are two pictures from my Jalpa removal/installation. Actually the new hose shown had too small a diameter, but it was an easy process to use this to pull the correct (1” ID) hose through.

Laust

 

[Laust]

I have not put a scope on my Jalpa tachometer, but had an easy transition (tachometer-wise) when converting from the Bosch CDI box to Electromotive’s TEC3 unit, which I believe is a 0-12V square wave.

I had some trouble with my Espada tachometer, but found D&M Restorations Tachometer Repair and Restoration in South Carolina who replaced the internals, so it worked well with Electromotive’s TEC3r unit. I am sure they could be helpful to you too.

A small detail to watch out for on the Jalpa Tachometer is the OE plastic needle, which over time bends up to (and interferes with) the glass. It can be upgraded to a lightweight aluminum needle.