Cleaning, ring gaps, bearing clearances..

With the expensive parts taken care of, it was finally time to start putting this $2000 adventure together.

The first step was to clean, clean, CLEAN everything. Yes, the machinist cleaned the engine block - but can it ever be too clean?

First, I purchased a thread-chasing tap set from Summit Racing. I had to augment the tap set with a few regular 1/4"NPT and 1/8"NPT pipe taps. I chased every thread in the block. The tap was inserted, started by hand, and then turned in, then out, then back in again until I had removed all of the accumulated stuff from the threads.

With all of the threads cleaned, I moved to my rifle cleaning kit. I applied some cleaning solvent to the wire brush and proceeded to brush every oil passage I could access. I ran the brush down through the main bearing area and into the camshaft bearing oil feeds. I ran the brush into each of the side plug passages into the main oil galley. I brushed each of the lifter oil galleys. Later I discovered the machinist had never removed the front main oil galley plug (located just above the top and front bolt of a Scout II's motor mount bracket). Because of this, I never brushed the main oil galley lengthwise and this almost came back to haunt me.

After the thread chasing and passage brushing, I moved on to the cylinder bores. I stopped at every automotive shop in town asking for lint-free shop rags with no success. The autopaint store offered to sell me some rather expensive painting tack rags, but I didn't think that is what I wanted. Ultimately, I settled for paper towels which did an OK job but did require some special care to keep the amount of lint to a minimum. Initially I purchased some TIDE for the bore cleanings, but other friends suggested I simply use Brake Cleaner. I bought a dozen cans of brake cleaner to go with the paper towels and started the cleaning.

First, I sprayed the #1 cylinder bore with solvent. I then wiped the bore clean with the paper towels. Once clean, I dipped a fresh paper towel into motor oil and then wiped down the cylinder wall with motor oil. I then used another fresh paper towel to wipe the cylinder bore clean. I repeated this process a number of times on each cylinder until the paper towels always came back clean. This process took several evenings to get everything CLEAN. Once I would finish for the night, I would re-apply a coating of motor oil to each cylinder bore to prevent rust.

Once the block had been properly cleaned, I turned my attention to the camshaft. I quickly wiped the camshaft down with solvent and fresh paper towels to remove the shipping oil. I then used the small canister of camshaft lube provided by the camshaft manufacturer to coat the camshaft lobes.

With the camshaft ready, I made a mistake. I neglected to first install both lifter oil galley front plugs. I installed the driver's side plug, but missed the passenger plug, hiding behind where the distributor shaft would be. DO make sure to install BOTH lifter oil galley plugs into the block, and make sure the front main oil galley plug (located just above the motor mount bracket on the driver's side motor mount on a Scout II).

I then carefully slid the new Iskendarian Racing camshaft into place through each of the camshaft bearings. The rear camshaft retaining plate was installed with a new gasket and torqued to specifications and the front camshaft retaining key was attached to the block with the large allen-head bolts and red Loctite. I placed my dial indicator on the end of the camshaft and confirmed the end-play was within factory specifications.

Next I cleaned the crank. It received the solvent and rifle brush treatment first, cleaning out each oil passage. After the brushing, I wiped each journal down with solvent, then with oil, then a clean towel, then oil, then a clean towel a few times until the towels always returned clean.

With the crank clean, I soaked each main bearing in motor oil for a short while and then installed them, and slowly lowered the crankshaft into place, making sure to align the timing marks on the camshaft timing gear and crankshaft timing gear correctly. With the crankshaft in place, I installed the top half of each bearing and the main bearing caps. I torqued the main bearing caps to the factory specification.

With the crank in place, I then proceeded to remove the main bearing caps one by one and plastigaged each bearing surface. I would remove the main cap, wipe the journal of oil and wipe the bearing of oil, insert the plastigage, and then torque things down. Remove the main bearing cap and compare the line of plastigage to the lines on the plastigage wrapper. Once I had confirmed the bearing clearances were within tolerance, I gently removed what was left of the plastigage on the crank and bearing, re-oil the two, and then reassemble.

With the crank and camshaft installed, I rotated the engine to make the #1 cylinder easiest to work on. I re-cleaned the cylinder bore. I then test fit the piston rings to the cylinder bore. I used two methods of making sure the rings were in the bore "square" - one method called for a ruler of some sort to be applied to the corner of the block and the cylinder bore measured equally from at least four points along the ring from the top of the cylinder bore. The other method I used was to place a straight edge across the block and slide the piston ring up to contact the straight edge.

I checked each of the 5 rings for the #1 cylinder for proper end-gap and fitted the piston rings to the piston. I used a piston ring installer. My biggest problems were with the oil rings - they required some getting used to. The spring ring would try to pop out.

My friend Rich helping out

I fitted every set of piston rings to the cylinder bores and then fit the rings to the pistons before I began any of the major assembly work of the engine block. The ring end-gaps were staggered. Examining the ring box revealed an "up" and a "down" to each ring that I needed to confirm.

With the crank and camshaft installed and the rings fitted to the cylinder bores and then installed on the pistons, it was time to start making my pile of parts resemble an assembled engine.