Blueprint 102 - Measuring 4g63 Crankshaft Endplay

4g63's are famous for hosing crankshaft thrust bearings. This video illustrates the process of how to check the thrust bearing clearance whether the motor's in the car or not. Of course in my case the motor's on a stand for this video. Lucky for me! In cases where the engine is still in the car, the same procedures can be used so long as the indicator is attached to the engine block. The plunger can be set up touching either the inside of the crank pulley or by removing the clutch cover plate and contacting the flywheel. What the thrust bearing does, is prevent the crankshaft from having lateral movement in the main bearings. If a crankshaft develops excessive movement here, clutch engagement and hydraulic problems will begin showing up, followed shortly thereafter by catastrophic failure of main bearings, rod bearings, connecting rod failures, oil pressure problems, or even broken blocks, crankshafts and rods in extreme cases. It's important that every 4g63 turbo engine is within spec on this measurement. When the crankshaft aggressively wears through the thrust bearing developing lateral play, this is called "crankwalk". On some block castings, replacing the bearings will NOT fix the problem. An engine block that is prone to crankwalking can not be fixed. The only option in these cases is to replace the shortblock and rotating assembly with new or used parts that are stronger than the one you've unfortunately encountered. For the 2g guys, the best option for repairing this problem is to remove the 7-bolt turbo shortblock your car came with and replace it with a 6-bolt from a 89-92.5 production date turbo DSM. Non-turbo blocks CAN be used; however, the block will not have oil squirters that aim towards the back of the pistons. That stream of oil aides lubrication to the wrist pins, cylinder bores, and somewhat cools the pistons. All good things on a turbo setup. Aside from that difference, there are no other differences between the non-turbo and turbo blocks. The pistons and thus the compression ratios are different, but that's it. Oil squirters can be machined into the main galleries of a non-turbo block, but it's more trouble than it's worth unless you can't find a turbo block. There are tons of differing theories about what causes crankwalk. Nearly all of them are plausible and logical arguments. I will not get into those debates in this video in order to focus on procedures for testing and replacement. Please feel free to google "crankwalk 4g63" and read the volumes of information available already. The arguments and gathered data are older than the Eclipse itself and in abundant supply on the internets. Magnus, RRE, VFAQ, and many other parts vendors have lengthy write-ups on their own research and development. The bottom line is that the 6-bolt shortblocks are LESS likely to suffer from this. Next time you see someone with a video that looks like it was shot with a potato asking "does this sound like crankwalk", you can send them this video. There's a reason for every noise, rather than focus on the sound, focus on eliminating the real problem. KNOW if it's out of spec.

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Blueprint 103 - Connecting Rods
Connecting rods are the crux of the engine. They're responsible for carrying the force of the explosions that occur in the combustion chamber and using it to turn the crankshaft. Oil clearance specifications of the "big end" and "small end" are crucial to maintaining consistent oil pressure. In this video we take 3 measurements: Rod Gap Rod Journal (also called Crank Pin) Diameters "Big End" Bore diameter Using the Journal diameters and the "Big End" Bores, you can calculate your oil clearances of each bearing. The process is illustrated here. Anyone rebuilding an engine who doesn't know its history should check all of these clearances whether or not they're re-using the rods. If the crank, bearings or connecting rods are going to be replaced, it's imperative that you measure the new parts as well to ensure they're in spec.

Turbo Elantra Bearing Failure Diagnosis
I had time to look at this thing up close. Go through the oil system, and check out all the bearings. Looks like another good study for my oil system series because it's the opposite problem that my GSX experienced. High oil pressure can be remedied a number of ways, but left unchecked can actually take a toll on your bearings. The way your engine bearings work, the parts they suspend are supported only by an oil film layer, and flow needs to be right in order for it to work as an actual bearing. If the oil supply is insufficient, then it loses the ability to suspend the part causing it to crash into the bearing surface. If oil flow is too great, friction is increased, the flow becomes turbulent, and the oil film doesn't form properly. High oil pressure can float and spin rod bearings, and that's worst-case scenario. I had several un-favorable conditions going on inside this engine and that makes it a little bit difficult to link what my engine experienced to any one singular thing. I think it's easier to look at it like some sort of perfect storm. From sub-standard parts for how the engine components would be used, to oil pressure, to part fatigue, to part history to abuse... this thing's got a little bit of everything working against it and that's why it's such a hilarious car. It was given to me with one condition. "See what this thing will do, and see how long it goes before it breaks." My take on it is, the parts are still less than ideal, and they've still got life left in them. It's worth fixing. These parts are worthless as a race motor, and normally I'd have junked 'em, but it's the Hyundai.

Calculate Your Compression Ratio
This is everything you need to do to calculate your compression ratio. No foolin'. Every equation and process demonstrated. Find all your variables. Know your exact compression ratio in every cylinder. This is how you do it. Just because your service manual says your car is 7.8:1 or 8.5:1 compression doesn't mean that it is. Whenever there are casting irregularities, variations in piston height, parts that have been machined, non-OE parts, or changes to your head gasket selection, your compression ratio WILL change. It's highly probable that you're only CLOSE to spec if you've never touched your engine at all since it was "born", and that it doesn't MATCH spec. Even if it did, how would you know? This. 5 variables. V1 Swept Volume V2 Deck Volume V3 Piston-to-deck clearance V4 Piston dish cc's V5 Head combustion chamber cc's The ratio math: V1+V2+V3+V4+V5 = volume of combustion chamber at BDC V2+V3+V4+V5 = volume of combustion chamber at TDC The ratio is... (V1+V2+V3+V4+V5) ÷ (V2+V3+V4+V5) : (V2+V3+V4+V5) ÷ (V2+V3+V4+V5) or BDC ÷ TDC : TDC ÷ TDC First you fill in the variables, then you calculate volumes, then you add the volumes, then you reduce the ratio (fraction). It's that easy. Here are your magic numbers: 0.7854 = Pi quartered to the ten thousandth 16.387 = number of cc's in a cubic inch. If you divide any number in cc's by 16.387 it gives you inches. If you multiply any number in cubic inches by 16.387 it gives you cc's. Quartering pi lets you use the calculation: BORE x BORE x STROKE x .7854 = volume of a cylinder instead of... π x (BORE ÷ 2) x (BORE ÷ 2) x STROKE = volume of a cylinder Either way is right. You get the same result if you calculate pi to the ten thousandth. While I apologize for all the math, no I don't. I'm really not sorry. You actually clicked here for it whether you realize it or not. This is ALL the math, the tests, and the whole process to calculate your cylinder volumes and compression individually even if you don't know any of your variables yet. All of my numbers are present for those who want to calculate out the last 3 cylinders out of curiosity just to see how it affects cylinder volumes and compression ratios from one cylinder to the next. Why would I do that for you? Why would I deprive you of that practice? Just assume that all 4 of my combustion chambers are 41.75 ml if you do this. Clicking like share and subscribe helps a channel grow. It also motivates me. Don't sweat the camera. It's enough to know that so many of you care about what I'm doing here. From the bottom of my atmospheric dump, I thank you all! This gift horse's teeth are all over the place, but he sometimes poops gold nuggets. PS: Use ATF for your piston dish volume tests, not alcohol. Of course it's better just to use the spec sheet included with your pistons... but not everyone gets that luxury. Water is just fine for head combustion chamber tests. Dry and re-oil all parts that water touches.