Bob's Component Resto, Part 36: Dusty gets a new motor, chapter two.

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cruiser

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Hello MoBros and MoSis':
Here's the latest with the Dart motor rebuild. Remember to check out chapter one if you need to get up to speed on this project. The block came back from the machine shop a week ago, as did the head. The head was completely rebuilt with new valves, springs, retainers, etc. - the full Monty. There was a lot of slop in the rocker shaft, but new bushings made it factory tight. This head, as you recall, is the factory original head that came with the block from the original December of 1973 build. Both the block and head passed their magnaflux checks with flying colors. This is always a concern with a full teardown of a core that you have little history on. In any case, all went well and both components were flawless aside from the usual wear of about 95K miles. I really like the block - high nickel content with additional side ribbing and well seasoned with a lot of heat/cold cycles - perfect for Dusty. The machine shop cleaned up the cylinders and didn't need to deck it. After its came back, both components went through two washings after being baked. I chased all screw holes, then prepped it for painting. (Note: Tim, the engine shop owner, allowed me to perform some of the unskilled labor items such as thread chasing and taping. Saved a lot of dough doing this stuff myself). We decided to go with Bill Hirsch engine paint which I've use before with excellent results. Very durable stuff, although they've stopped selling it in spray cans, so we had to have a quart of it put into cans at the local NAPA. Couldn't use a HVLP sprayer for several reasons which I won't go into. In any case, it came out great and we'll be powder coating the oil pan and valve cover (instead of painting them) for that additional durability. This brand of engine paint requires a two week cure time before you can put heat to it, but can be handled within two days to allow assembly of the motor. I've attached several photos of the painting progress.
So that's all for now. Chapter three will cover reassembly and dressing the motor, and break-in and driving impressions. Stay tuned!

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More progress this morning when we reconditioned the connecting rods. The first photo is of the #1 rod after being media blasted next to the #2 rod before blasting. The next photo is of the weighing table where we balanced up the rods and matched them with the pistons (photo#3) by weight. The final photo is a shot of some of the math that went into the balancing process. We got all three rod/piston assemblies to within three grams of one another, so I anticipate that this will be a very smooth running motor. Maybe too much info, but there it is for you detail oriented guys/gals. Enjoy!

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Just a quick update on the new Dart motor going into Dusty. I drove her to the shop this morning for the removal of the old engine. The removal and installation process should take about a week. As a reminder, the engine that came with my Duster when I purchased the car in April of 2019 was not the factory original engine. The factory motor was removed in 1988 and scrapped. In its place went a parts store crate engine, which is the engine with low compression that is presently being removed. The Dart engine is the newly rebuilt slant six (presently on an engine stand) that came out of a 1974 Dart. It is the correct casting number and has a cast date a bit closer (although not completely correct) for my October of 1973 build date of my car. The enclosed photo was shot this morning. This is the driver's side of the Dart engine showing the correct casting number (2806830) for a 1968 - 1975 high deck, forged crank slant six. The "-4" after the casting number refers to the casting pattern number used to cast this block. The 3353 casting date corresponds to Dec. 1, 1973. The letters "BH" to the right denote extra side ribbing. I'll post an update once the Dart engine goes into Dusty with driving impressions and installation noted. Until then, be well all!

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I was just wondering about this just the other day, Bob...

Glad to hear you're going to get the engine in before the snow flies, but are the guys at Huttner going to give you some extra warranty time to break it in? After all, winter is coming...

Or are they going to do this before handing the car back to you?

Regardless, looking good!
 
No, the engine will be broken in after installation into the Duster. So I'll need to put some miles on her before the snow flies. Thanks - BOB
 
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