Overhauled engine v.s. New Engine

[steppinthrax]

Just curious, I read somewhere that when an engine is overhauled (properly) it will not have the same reliability as a New engine (from factory)?

My understanding is if you replace seals, gaskets, rings, bearings and any "soft" component, the engine should function with the same reliability as a new engine?

 

[JCH13]

Just curious, I read somewhere that when an engine is overhauled (properly) it will not have the same reliability as a New engine (from factory)?

My understanding is if you replace seals, gaskets, rings, bearings and any "soft" component, the engine should function with the same reliability as a new engine?

In theory-land, yes. In practice the engine better be rebuilt by a shop that "does it right" and doesn't cut any corners. There are a lot places to screw up when rebuilding an engine.

 

[Howard]

Cylinder bores too

 

[ghost recon88]

Also, if the right place is rebuilding it they will use parts that corrected factory flaws, namely gaskets and bearings.

 

[jagec]

Also, if the right place is rebuilding it they will use parts that corrected factory flaws, namely gaskets and bearings.

And higher-end parts in some cases.

I mean, if you're going to all the trouble of rebuilding an engine, might as well upgrade some components...forged vs. cast, etc.

I'd trust a GOOD shop rebuilding an engine with quality parts over a new engine.

 

[TakeNoPrisoners]

Overhauls done right are just as good as a new never used engine. Doing it right isn't always cheap; sometimes it is impossible to do a good overhaul job if the engine block was damaged beyond the point where it is repairable. As in the case where an engine was run for a long time after it threw a bearing.

 

[phucheneh]

Beyond the competency of a small engine building shop; A lot of very large reman facilities are quite terrible. Reusing parts that shouldn't be, mixing and matching bearing sizes (to correct poor machining), ect.

Ever seen an autozone remanned starter opened up? The motor usually looks like it was pulled from a junkyard. They just replace the solenoid and paint it. So I'm certainly not going to trust a company that remans engines for parts stores.

When talking about a rebuild at a local shop, one good question is WHY is the rebuild needed? If someone managed to trash a motor with, say, a lack of oil changes, I don't care who rebuilds it- throw that thing in a trash heap.

 

[phucheneh]

Overhauls done right are just as good as a new never used engine. Doing it right isn't always cheap; sometimes it is impossible to do a good overhaul job if the engine block was damaged beyond the point where it is repairable. As in the case where an engine was run for a long time after it threw a bearing.

Spun bearings are repairable, but the crank and any applicable rods need to be replaced. Thrown rods..well, you can patch the hole in the block with the some chickenwire and JB weld, I guess.

The stuff I worry about is little bits of metal, gunk, whatever that don't get properly cleaned out. To properly rebuild an engine, it takes COPIOUS attention to detail. Even if the facility tanks the block and does good machine work, every single oil passage still needs to be checked. Every cylinder need to be cleaned by hand to remove honing grit. Ect.

 

[HeXen]

Ever seen an autozone remanned starter opened up? The motor usually looks like it was pulled from a junkyard. They just replace the solenoid and paint it. So I'm certainly not going to trust a company that remans engines for parts stores.

don't they still have the lifetime warranty?

"Duralast starters are remanufactured with the most current technological improvements and triple tested to provide original equipment quality and durability.
Designed to deliver torque output for starting performance that meets or exceeds the original equipment on your vehicle
All wear components (brushes and bushings) are always 100 percent new
Every unit is triple tested (component, subassembly and end of line) to ensure quality and performance"

 

[Howard]

don't they still have the lifetime warranty?

"Duralast starters are remanufactured with the most current technological improvements and triple tested to provide original equipment quality and durability.
Designed to deliver torque output for starting performance that meets or exceeds the original equipment on your vehicle
All wear components (brushes and bushings) are always 100 percent new
Every unit is triple tested (component, subassembly and end of line) to ensure quality and performance"

Motor is not normally a wear component

 

[phucheneh]

^_^

Motor is not normally a wear component

Now, things may have changed. And also, I might be thinking of Advance starters. But I've definitely seen multiple 'remans' taken apart, only to find that it didn't appear anything had been done to them. I remain of the opinion that with a lot of these 'ultra-refurbished quadruple-inspected' parts, there is only one goal:

Fix what's broken, and resell it. Starter solenoid burned out? Slap a new one on it, paint it, sell it. Alternator have a bad voltage regulator? Slap a new one on it, paint it, sell it. Et al.

...I guess I'm not exactly a trusting person.

edit: I kinda quoted the wrong person. Brushes are supposed to be the only wear component in the motor (plus bushings for the commutator (iirc that's what the spinning bit is called)). But in at least one example, I saw used brushes.

Protip: parts stores don't like doing 'returns' on things you took apart.^_^

 

[HeXen]

but if its fully replaceable warranty then it wouldn't really matter. I know it used to be years ago, if it broke you just swapped it for a replacement.

 

[phucheneh]

but if its fully replaceable warranty then it wouldn't really matter. I know it used to be years ago, if it broke you just swapped it for a replacement.

I never follow this logic. If you aren't paying labor/your time is worth nothing, then okay, put four starters on the car. Otherwise...

And honestly this isn't even limited to parts stores. It's a sad situation.

Ask me about the Volvo I put six starters on...Yeah, I think he should've popped on the 'new' model from the parts department, ludicrously priced as it was.

Every single starter was in warranty, but we could do nothing but replace it with another reman. I don't think he enjoyed his six dealer visits. And yes, it was the starter, not a battery/cabling/anything else issue. They bench-tested bad.

Advisor: "Well, can't something be MAKING the starter go bad? I can't just tell this guy that our parts are terrible..."

Me: "Then I guess you're going to have to start making up bullshit..."

I really need to post a thread about my dealer experiences, and why I now choose to work for myself...the auto repair industry is in such a laughable state of decline.

 

[thedarkwolf]

I put a brand spanking new Advanced master cylinder on my van and it died in 2 weeks. 2nd one made it 3 days lol. I went to Advanced and asked for my money back and all they did was offer me a 3rd to which I used some fowl language and told them to just keep it. Went across the street to Napa a got a reman unit and it worked fine.


I've rebuilt two of my own engines and didn't half ass anything on either. Had all the machine work done and upgraded to better than stock in several areas. One never gave me any problems the 2nd the block cracked in one of the cylinders after 20k miles. Probably just a defect in the block that finally showed up after 180k miles.

 

[HarryLui]

Here's a manufactured jasper engine story..

To sum up, they used the wrong key for the crank timing sprocket, damaged the crank.

http://www.turbododge.com/forums/f4/f15/405419-never-ending-cam-timing-problem.html

 

[bruceb]

The critical parts of a rebuild are properly sized and polished rod / crank journals, along with the proper size bearings. Along with an align hone to insure they are all in a perfect straight line. The rebore and cross hatching on the cylinder walls are critical to good ring operation. Ring gaps must be correct, as must crankshaft end play. Valve guides and valve seat angles are also fairly critical, as is a good cleaning of the entire engine block (including all passages) before assembly is done. As mentioned above, if the shop or you knows what to do, how to do it and does not cut corners, a rebuilt will be just fine and less than a reman motor in most cases. Best option is a new crate motor, but that will cost more.

 

[JCH13]

The critical parts of a rebuild are properly sized and polished rod / crank journals, along with the proper size bearings. Along with an align hone to insure they are all in a perfect straight line. The rebore and cross hatching on the cylinder walls are critical to good ring operation. Ring gaps must be correct, as must crankshaft end play. Valve guides and valve seat angles are also fairly critical, as is a good cleaning of the entire engine block (including all passages) before assembly is done. As mentioned above, if the shop or you knows what to do, how to do it and does not cut corners, a rebuilt will be just fine and less than a reman motor in most cases. Best option is a new crate motor, but that will cost more.

So... the critical parts of a rebuild are... everything?

 

[Pulsar]

We wash our blocks, interior, exterior, and all passages, with a washer that runs in the 5+ thousand psi and above range (not getting into specifics...). Afterwards the entire block is rinsed into a micrometer range set of filters and each filter is weighed to determine contamination levels.

It's pretty tough to get a reman / rebuilt block even close to a new one.

 

[Doppel]

I put a brand spanking new Advanced master cylinder on my van and it died in 2 weeks. 2nd one made it 3 days lol. I went to Advanced and asked for my money back and all they did was offer me a 3rd to which I used some fowl language and told them to just keep it. Went across the street to Napa a got a reman unit and it worked fine.


I've rebuilt two of my own engines and didn't half ass anything on either. Had all the machine work done and upgraded to better than stock in several areas. One never gave me any problems the 2nd the block cracked in one of the cylinders after 20k miles. Probably just a defect in the block that finally showed up after 180k miles.

I cheaped out with an advance auto parts clutch slave cylinder. Original had lasted 7-8 years. The replacement started to leak within one. I replaced it and sold shortly thereafter, so no idea how the second held out. Saving a little money is good but most of the effort here is labor, not a few bucks on parts. It's just not worth it sometimes to save a little cash if you just have to redo it.

 

[phucheneh]

You know what's weird? I did a clutch for a buddy a little while ago, and used autozone parts. The idea was that he was giving his girlfriend the car, and if she smoked the clutch, we could just use their liberal warranty (difference between my prior stance- part not faulty, just abused). Although the clutch ended up being a pretty recognizable brand once you pulled it out of the Duralast box...Sachs, maybe?

Anyway, the surprise: The slave and master cylinders, priced competitively, were brand new. Car's been going for months with no issues. +1 for Autozone. Too bad the service in your store is still balls covered in shit.

We wash our blocks, interior, exterior, and all passages, with a washer that runs in the 5+ thousand psi and above range (not getting into specifics...). Afterwards the entire block is rinsed into a micrometer range set of filters and each filter is weighed to determine contamination levels.

It's pretty tough to get a reman / rebuilt block even close to a new one.

To be fair, even the OEM has to do a lot to make sure all the sand, shavings, ect is out of the block and heads. Plus cleaning the cylinders*. But they probably have some complex machinery that helps enable consistency and the VERY low failure rates seen in modern engines. That's one reason I worry about remans and/or rebuilds- in a time where an engine's mechanical components can EASILY last 300k miles, exactly what did someone do to this engine that sent it back for a rebuild?

*I mentioned it before, but this is soooo overlooked. It takes effort (or special equipment) to get all that grit out of the cylinder walls after honing. I weep when I hear of someone getting a block fresh from the machine shop, and just stabbing the new pistons right in it. So long, piston rings/crosshatching!

That's the big thing really- just having attention to detail. With common sense and a little instruction, engines are not very hard to build...they're just time-consuming. I've gotta be sure every little spec of crap is out of the engine, whatever that takes. Cleaning and measuring take WAY longer than assembling, and I simple just don't trust anyone other than myself to do that...shops are on a budget/timetable, reman factories are just another corporation trying to save a few bucks.

The only exception for me would be, like, a specialty engine shop with a REALLY good reputation...and REALLY high prices to go with it, because being thorough definitely costs a lot (of time and therefore money).

 

[Pulsar]

You know what's weird? I did a clutch for a buddy a little while ago, and used autozone parts. The idea was that he was giving his girlfriend the car, and if she smoked the clutch, we could just use their liberal warranty (difference between my prior stance- part not faulty, just abused). Although the clutch ended up being a pretty recognizable brand once you pulled it out of the Duralast box...Sachs, maybe?

Anyway, the surprise: The slave and master cylinders, priced competitively, were brand new. Car's been going for months with no issues. +1 for Autozone. Too bad the service in your store is still balls covered in shit.



To be fair, even the OEM has to do a lot to make sure all the sand, shavings, ect is out of the block and heads. Plus cleaning the cylinders*. But they probably have some complex machinery that helps enable consistency and the VERY low failure rates seen in modern engines. That's one reason I worry about remans and/or rebuilds- in a time where an engine's mechanical components can EASILY last 300k miles, exactly what did someone do to this engine that sent it back for a rebuild?

*I mentioned it before, but this is soooo overlooked. It takes effort (or special equipment) to get all that grit out of the cylinder walls after honing. I weep when I hear of someone getting a block fresh from the machine shop, and just stabbing the new pistons right in it. So long, piston rings/crosshatching!

That's the big thing really- just having attention to detail. With common sense and a little instruction, engines are not very hard to build...they're just time-consuming. I've gotta be sure every little spec of crap is out of the engine, whatever that takes. Cleaning and measuring take WAY longer than assembling, and I simple just don't trust anyone other than myself to do that...shops are on a budget/timetable, reman factories are just another corporation trying to save a few bucks.

The only exception for me would be, like, a specialty engine shop with a REALLY good reputation...and REALLY high prices to go with it, because being thorough definitely costs a lot (of time and therefore money).

I am the OEM =), and our robotic washers are ridiculous, with mag seperators and all sorts of fun stuff.