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Discussion Starter · #1 ·
Working on a '77 Spider with a T255 Spica in it.
The TA tested fine on the stove, extending to 28mm at 175 degrees. I cobbled together a dummy actuator and set it to length. When inserted, the dummy closes down the pump gap to zero and then some. I turned the screw all the way clockwise. Still less than .019 so shimming the TA is in order.

It looks like I'll need 3-4mm shims.

Does that seem like a lot to have to raise the TA out of the pump?
 

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Discussion Starter · #2 ·
Plot Thickens...

Installed the T/A bot with, and without shims.

The pump gap never comes close to .019. Think the actuator is not strong enough. :(:(
 

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When you did the bench test on the TA, did you put some pressure on the piston to make sure it didn't push back in? Although, usually if the TA is bad it won't extend at all.

If you remove the lower part of the TA and push down on the adjustment screw in the pump with a screwdriver, can you make the throttle arm move?

As far as shims go, you want to bring it back to 27mm apparent extension, so a single 2mm washer is enough. That will bring back your cold start/running performance.
 

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Discussion Starter · #4 ·
When you did the bench test on the TA, did you put some pressure on the piston to make sure it didn't push back in? Although, usually if the TA is bad it won't extend at all.

If you remove the lower part of the TA and push down on the adjustment screw in the pump with a screwdriver, can you make the throttle arm move?

As far as shims go, you want to bring it back to 27mm apparent extension, so a single 2mm washer is enough. That will bring back your cold start/running performance.
I did not try to push the TA plunger in while testing. I can push the adjustment screw and close the gap to zero, no problem. I made a dummy actuator and set it at 28mm, so I can keep the process moving...
 

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The pump spec is [email protected] Technically the bench check includes a 4kg force against the piston as it extends. As long as the pump gap is .019" at 175F (long rod disconnected), going to zero as the engine reaches full ops temp, you're good. Cold starts/running may be a little harder with a fixed position dummy TA installed, but summertime it should not be significant issue.
 

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Discussion Starter · #6 ·
I'll pull it out this evening and re-test, this time applying force to the tip once it extends.
 

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Discussion Starter · #7 ·
Results

Shimmed the TA and adjusted to get .019 pump gap at 175-180 degrees.
Adjusted FCS, long and short links.

The car runs nicely and I have an even, light-tan color on the plugs. :):)
 

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Discussion Starter · #9 ·
Sure does run better.

Only issue left is that it takes a few revolutions to fire when cold. I verified the CSS is audible. May have to richen it (the solenoid) up a little.
 

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2-3 revolutions of the engine before firing is pretty normal for Spica. Remember, the pump has to build up pressure in the hard lines before the injectors will actually squirt fuel.
 
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