The Rebuild

     It took a little while for us to get the motor and all the parts needed back from the machine shop, but when we did, we got to work. The first thing that was done is the motor was completely masked off and all the paint was stripped off the block, oil pan, accessories, and timing cover. Once it was all stripped we cleaned out the block just to make sure no paint chips or dust got into oil passages or bearing surfaces. Now the motor had new sleeves installed, new pistons on the rods, and no paint, it was ready to go back together.

When assembling the motor and checking all tolerances we realized that, because of the machine work, our head and pistons had -.044 in. of clearance (meaning they would collide). All this means is that we had to special order some MLS head gaskets that were .120 in. thick to archive the desired head to piston clearance.

It's a good thing we caught that because a clearance issue like that could cause some serious damage to the heads, pistons, bearings and even the crankshaft if it was run long enough.

Once fully assembled, the heads, valley, and any exposed area to the inside of the motor were masked off to prep for paint. We decided to go with the same color it that it came in with, bright red.

After the motor long block was assembled, the customer wanted us to run the motor and set timing on a run stand before the motor went into the car. While installing and tuning motors is no challenge for us here, we have never run an engine on a stand before. We didn't even have a run stand!

Some clever design by one of the mechanics here allowed us to temporarily convert a regular engine stand into a stand to run a motor on. All that was done is a support was made to reinforce the front of the motor to prevent it from rotating and possibly even falling over.

In order to ensure that the motor had proper cooling, we had to run some sort of coolant while it was on the run stand to prevent the motor from overheating. Now this flathead has a very interesting design, it actually has two water pumps! One for each side of the block. This is because there is no way for coolant to cross over between the sides of the motor. 

As seen in the photo we achieved proper cooling by simply looping both sides of the cooling system. A very simple solution that worked long enough for us to set timing and make sure everything is running as expected. This, however, was not enough to keep the motor running for much longer than around fifteen minutes due to there not being enough surface area to cool the motor.

After everything was running correctly and we had timing where we wanted, it was time to install the motor in the car! Catch that part of the story in the next post.