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The compressed air pipes and passageways and fittings have been up sized to 5/16" and the air distributor has been modified to use ball bearings to lift each ball valve. This should decrease the ware noted on the brass cam. 

The coolant leak was hard to locate since no sign of leakage was noted at the head gasket. So I made plates and plugs to seal the cooling system and pressurized it with air and searched with soapy water for the leak and was not successful. So I poured aluminum paint into the cooling system and pressurized that and rotated the engine 360 degrees on the engine stand then drained the paint and let the engine set for a few days to dry. Then I removed the head on the left bank and noted that the #1 combustion chamber was painted aluminum. The trail also was evident. It was coming from the air injection port in the cylinder wall. The drilling was close to the top of the block but evidently there was not enough casting at the top on #1 cylinder and the hole nicked the cooling jacket. With a small wire hook I was able to confirm a small slit in the bottom of the hole. To correct the problem I made a new fitting to adapt the 90 degree air fitting to the block and extended it all the way through past the open slit up to the iron cylinder wall and put high temp sealer on the fitting. I then pressurized the cooling system with air and there was no leak now. 

During the road test I noted that the brakes were not up to par with the rest of the car as it required far too much peddle pressure to slow the car. Just looking at the size of the caliper pistons I had guessed that the ratio of master cylinder to caliper pistons was ok and maybe even a little over powered thus making the brakes touchy. But the opposite was true. I contacted Wilwood calipers and gave them all the measurements and they said my guess was wrong and the peddle to caliper ratio was wrong and I either needed to decrease the bore size of the master cylinder or add a brake booster.

I decided to install a brake booster system since the later MGB had a booster system. However, this required a different peddle box and peddles. I was lucky to find a peddle box and peddles at a local British car restoration shop in Nashville called "JD's".  It took some modifying to fit it to this older body.

The booster required a vacuum chamber to draw from so I had to tap into each intake runner in my manifolds and pipe that vacuum to a vacuum chamber. This vacuum chamber was needed anyway to operate a MAP sensor for the direct ignition system plus it was impossible to read manifold pressure on my gauge due to fluctuations of the needle at low RPM as I had taped it into only one runner of the manifolds.

Two major problems showed up when the four link hood hinge hit the master cylinder reservoir. So I had to make a remote reservoir. A second problem was that the clutch master cylinder reservoir cap could not be removed and the master cylinder could not be relocated nor was the body able to be modified in that area. So I drilled a hole into the side of the reservoir and inserted a tube for filling the reservoir.

As soon as the engine is back into the car I can road test it again to see if there are any more problems that need addressing.

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