Man-hour estimate

[JHZR2]

Hello,

Having a discussion with a freidn regarding the time required to do substantial cleanup and rebuild of complex items. De-sludging of an engine was a good analog to the system we are interested in, so was hoping someone could help with an idea.

Let's say you have a high end engine, like an Audi RS4 or similar. Lots of complex parts, turbo, whatever else. Say it is massively sludged so everything needs to get taken apart, cleaned, brought to spec and then rebuilt.

What kind of a man-hour requirement is that?

Thanks!

 

[snapcrackle12]

46-50 hours

 

[bdcardinal]

Originally Posted By: snapcrackle12
46-50 hours


At least, there is a reason why a reman assembly is usually cheaper. Plus the warranty is usually better on an assembly versus a shop doing it themselves.

 

[snapcrackle12]

37 hours for long block

 

[snapcrackle12]

Like to do long blocks or assembly, better warranty with less overall cost to the customer

 

[JHZR2]

Originally Posted By: bdcardinal
Originally Posted By: snapcrackle12
46-50 hours


At least, there is a reason why a reman assembly is usually cheaper. Plus the warranty is usually better on an assembly versus a shop doing it themselves.



Sorry, need to clarify. This isnt really an automotive discussion. There is no real engine in place, no discussion of long blocks or remanufactured assemblies.

Im an trying to draw an analogy in man hours to another system that needs cleaning and refurbishment, so the actual man-hour estimate to truly tear down, clean out, and then refurbish and make like new for a high-end, high complexity engine is the interest to me.

I need hours, not whether a long block or remanufactured assembly is the right choice for a car. I need an idea of the time to fully refurbish a sludged up piece of complex equipment for a time estimate check on an entirely different (but similar in complexity) piece of equipment.

 

[snapcrackle12]

any complex system is going to be labor intensive. If it was easy everybody would do it.

 

[JHZR2]

Originally Posted By: snapcrackle12
any complex system is going to be labor intensive. If it was easy everybody would do it.


I get that. No kidding. Just trying to draw an analogy, which is why I requested an estimate of time.

 

[snapcrackle12]

happy to help

 

[rationull]

I'm used to doing estimates on software, where each case tends to be quite different from previous cases, but is it really possible to give on estimate on something like this without 100-200% variance given the lack of detail in the description?

 

[Scott_Tucker]

The actual desludging would not take that long if the shop had proper cleaning equipment. The labor would be in the tear down.

 

[Hokiefyd]

You're looking for hours, but won't say what the job is. If you can tell us exactly what the job is, we can probably help a little more.

 

[JHZR2]

Originally Posted By: Hokiefyd
You're looking for hours, but won't say what the job is. If you can tell us exactly what the job is, we can probably help a little more.


It is an adsorption process with a chemical reactor and a bunch of ancillary equipment, as well as sensors, controls, etc. that is so wildly different from an engine that it is tough to draw a relevance to it.

But my read on things is that rebuilding an engine via complete teardown, which Ive never done and is a massively complex task to do cleanly and correctly.

And sludge cleaning is going to be part of the job.

So my basis was going to be the man hours for a tear down, clean and rebuild for an advanced engine, would give me a basis that I would then scale by weight and volume to provide a rough estimate. I have no HAZMAT to consider in my case.

 

[Smoky14]

Find an HONEST tech and turn him loose, pay the price and move on. I've gotten into just what you describe and it takes however long it takes. How important to you is getting the job done.

Fair is fair....only you know how inportant it is to you.

 

[JHZR2]

Originally Posted By: Smoky14
Find an HONEST tech and turn him loose, pay the price and move on. I've gotten into just what you describe and it takes however long it takes. How important to you is getting the job done.

Fair is fair....only you know how inportant it is to you.


This isnt about techs or engines. it is about hour estimation of a job of similar complexity in an unrelated area, but where the complexity is analogous to rebuilding an engine.

This isnt a "find an honest tech" thing, the system is built and maintained by PhDs.

 

[mechtech2]

It depends on what cleaning facilities there are available to the guy working on it.
Fresh solvent in good tanks? Ultra sound? Old weak solvent in cramped conditions?
The cleaning is a huge variable. It can suck up the most the time.

 

[doitmyself]

JHZR,

If you end up hiring a woman for your project, will the man hour estimate still apply?

HaHa. Based on the difficulty people are having comprehending your request, I couldn't resist throwing in another misdirected post.

I wonder if a dedicated engine remanufacturer could help you out?

Take care and good luck.

http://www.jasperengines.com/index.php

 

[charmicarmicat]

Originally Posted By: JHZR2
So my basis was going to be the man hours for a tear down, clean and rebuild for an advanced engine, would give me a basis that I would then scale by weight and volume to provide a rough estimate. I have no HAZMAT to consider in my case.


I once built a model engine out of plastic in about 15 minutes. It weighed about 50 grams. If we assume the RS4 engine weighs 200kg, we can estimate (via scaling by weight) that it should take about 6 man-months to rebuild the RS4 engine. At least that is a basis you could use for your estimate.

I hope this helps!

But more on task, it can vary, a whole bunch. I've seen an L28 engine rebuilt in about 6 man-hours. Then again, jobs like rebuilding just the valves on BMW V8 engines can be tens of man hours, I think I saw 50 man-hours billed to rebuild the VANOS system on a 90s BMW V8. It can be all over the place.