Quickie 2.0 Rebuild |
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Quickie 2.0 Rebuild |
McMark |
Oct 17 2016, 05:21 PM
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#1
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
One of my winter tasks is to build a stock 2.0 with my MicroSquirt fuel injection that I can install in my car and get it dyno tuned. That's been the missing piece of my MicroSquirt setup for the last few years.
Since there isn't much demand for a stock 2.0, I just plan on doing the minimum to build a solid motor. I plan on having the valves reground, cylinder surfaces machined and reringing the pistons. Regrinding the cam and rebuilding the rods and all new bearings as well. This should give me a motor that will last through the testing, and be worth something when I'm done to pass on to a new owner at a nice price. This thread does not represent my standard procedures for rebuilding engines. This is a special case and special circumstances. For those of you on a budget, but looking to refresh their motor should appreciate this writeup. Starting off with a core engine. The previous owner mentioned this engine had a 'knock', so I'll be on the lookout for what might have caused that. This is a 'GC' code engine with air injection ports in the heads. Attached image(s) |
DM_2000 |
Oct 2 2017, 05:34 PM
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#2
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Member Group: Members Posts: 217 Joined: 16-August 17 From: PA Member No.: 21,351 Region Association: None |
A few things on this thread. I've repaired / put together countless engines across many brands and have seen lots of damage tried various repairs to see what would happen when an opportunity presents it's self.
Building a "junkyard" motor is a good way to build a decent used engine that is sometimes difficult to find. ( Not all parts are to OE spec, some stuff is worn, attention is paid to crankshaft journals and bearings as these are a typical failure point. ) Piston rings are not used to center or support pistons in their bores. Pistons ( Aluminum ) expand a greater rate than iron bores so if rings supported pistons, they would either be too lose when cold or seize when hot. Piston skirts accomplish holding the pistons square to the bore, over a surprisingly small area due to skirts having an oval diameter and barrel shape lengthwise. For removing piston pins, a 3/8" socket extension dropped through the pin and a 2nd one clipped on works wonders as a drift. This way the "drift" does not walk on the end of the pin risking surface damage. Think valve guide driver / bushing driver. For dents in metal, I hammer them flat then scrape level to the surface. This way a minimal amount of material is removed. It is critical to remove any metal that is flaking off. I'd rather have a somewhat tight fit for keys than loose. Tightish keys help reduce fretting when a part is installed on a shaft. Crankshaft rotation on a 4 cylinder engine is far from smooth, some of this is each cylinder firing and the rest of it is camshaft. The fewer lobes on a cam the rougher the rotation is. Turn the cam and it will be difficult as a lifter rides up a lobe then it will snap as the lobe rides down the other side of the lobe. |
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