Machine shop time, How many hours to prep case, crank, bearings? |
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Machine shop time, How many hours to prep case, crank, bearings? |
Phoenix914 |
Sep 17 2020, 06:21 PM
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#1
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Member Group: Members Posts: 389 Joined: 6-December 06 From: Oviedo, FL Member No.: 7,322 Region Association: South East States |
Greetings All!
I just recently dropped off my 2.0 (GA) case and 71mm crankshaft to get checked at a local machine shop in preparation for a rebuild. Today they called and said for align bore, decking the registers, polishing the crankshaft, and mocking up the assembly with fitted and numbered main bearings it would be 30 hours of work. Does that sound reasonable? It's honestly a lot more than I expected and will add $$$ to my budget for this rebuild. Should I look for another case, maybe a 1.7, that is in better condition or has already been prepped? I'm not an expert builder and some things are worth paying for, but man that's a lot of money! Thanks for any advice! |
mepstein |
Sep 17 2020, 06:30 PM
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#2
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914-6 GT in waiting Group: Members Posts: 19,142 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
Does it need all that stuff? Does it not measure to spec or are you asking to have it done just to be sure. When I worked at the shop, micro polishing a crankshaft was ~$200-250. We generally didn’t align bore or deck the registers on the aluminum cases unless they were out of spec and tried not to rebuild mag cases unless there was a strong reason too. We only worked on 6 cylinder engine.
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Phoenix914 |
Sep 17 2020, 06:58 PM
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#3
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Member Group: Members Posts: 389 Joined: 6-December 06 From: Oviedo, FL Member No.: 7,322 Region Association: South East States |
Does it need all that stuff? Does it not measure to spec or are you asking to have it done just to be sure. When I worked at the shop, micro polishing a crankshaft was ~$200-250. We generally didn’t align bore or deck the registers on the aluminum cases unless they were out of spec and tried not to rebuild mag cases unless there was a strong reason too. We only worked on 6 cylinder engine. When I dropped the case off, I asked to have it checked for needing an align bore and registers decked. Today, the guy told me it needed those services. I have to trust the shop and their expertise, but I'm wondering if their time estimate for the work is in the ball park. From what I've read, GA cases typically have fallen registers and have to be decked, so that's no surprise. The align bore...I don't know (IMG:style_emoticons/default/confused24.gif) |
Superhawk996 |
Sep 17 2020, 07:23 PM
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#4
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914 Guru Group: Members Posts: 5,673 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
Not that outrageous. Most machine shops price by the component job (line bore, deck, polish crank, etc.) not the hour. But on the whole, your talking about man hours just to do mock up work fitting, and measurement of bearings that you could be doing. The shop expects and deserves to get paid for their effrots.
Unless they do lots of setups for decking for example, you're goint to pay machinist time for a one off set up. You're talking 1-1 1/2 hour just to tram the head of the mill, put the case on the table. and get it mounted securely but yet without deforming the case that will then spring back when unbolted. Find the fly cutter, make sure it is set up well, and then do the cutting which is another 1/2 hour or so. Now unbolt that case half and do the other. You get the idea, it all adds up. |
Phoenix914 |
Sep 17 2020, 07:36 PM
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#5
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Member Group: Members Posts: 389 Joined: 6-December 06 From: Oviedo, FL Member No.: 7,322 Region Association: South East States |
Not that outrageous. Most machine shops price by the component job (line bore, deck, polish crank, etc.) not the hour. But on the whole, your talking about man hours just to do mock up work fitting, and measurement of bearings that you could be doing. The shop expects and deserves to get paid for their effrots. Unless they do lots of setups for decking for example, you're goint to pay machinist time for a one off set up. You're talking 1-1 1/2 hour just to tram the head of the mill, put the case on the table. and get it mounted securely but yet without deforming the case that will then spring back when unbolted. Find the fly cutter, make sure it is set up well, and then do the cutting which is another 1/2 hour or so. Now unbolt that case half and do the other. You get the idea, it all adds up. I certainly don't begrudge anyone getting paid for their work. I appreciate highly skilled people who can do work I wouldn't know how to start. This was just a sanity check, mostly. Thanks for your experienced input, gents! |
mepstein |
Sep 17 2020, 07:42 PM
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#6
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914-6 GT in waiting Group: Members Posts: 19,142 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
I would check around. Some shops do it often and can charge less compared to specialty, one off work. Plus, a 914 case is cheap and easy to ship. Wrap it up well and then ziptie in a yellow and black plastic crate from a home store.
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Superhawk996 |
Sep 17 2020, 07:51 PM
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#7
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914 Guru Group: Members Posts: 5,673 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
I certainly don't begrudge anyone getting paid for their work. I appreciate highly skilled people who can do work I wouldn't know how to start. This was just a sanity check, mostly. Thanks for your experienced input, gents! Hopefully I didn't imply that. Certainly didn't mean to. I do as much of my own machine work as I can. I have a a sense of what it would take me, but, I'll readily admit I'm not as efficient as a professional machinist that does machine work all day, every day. Even then, I don't have the tooling to do something like a line bore (yet . . .). So may be a bit high, but not outrageous. I'd assume that will run you about $3k in labor. As a benchmark you can look at a Raby engine at $20K and see why he's getting paid that amount . . . all realted to the man hours and machine work that it takes to build an engine like that. You're at $3k and you've only laid the foundation but haven't even put in the man hours to assemble, mock up, check fits and geometry, set up on dyno, run it in, etc. In a mass produced world of cheap labor, it's easy to overlook how long it takes to do things. I do it all the time when I tell my wife it will take an hour and then I spend 3 on any given task. |
Jake Raby |
Sep 17 2020, 08:18 PM
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#8
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
I started prepping an engine last Friday.When I started, I had previously completed the dynamic balancing, which added another day onto things.
Just today I had all the work done for assembly, which will start tomorrow. I don't even keep track of the hours, because I don't bill by the hour. I propose the whole job as a flat cost. The time doesn't matter. This one is a stroker, so that adds one day onto my work, generally speaking. 30 hours for a machine shop sounds about right, IF they are blueprinting the assembly, and also balancing the components, along with the other items that you posted. Today it's a lot more than just building these engines. It's a full restoration effort, at the same time. If you have attention to detail, time to do these tasks can easily dip into the triple digits when it comes to hour count. That's why I don't keep track of it, I don't want to see the fact that I've been doing this for 28 years and I still don't make more than minimum wage. This post has been edited by Jake Raby: Sep 17 2020, 08:22 PM Attached thumbnail(s) |
mepstein |
Sep 17 2020, 08:39 PM
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#9
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914-6 GT in waiting Group: Members Posts: 19,142 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
We always used to laugh about the 40 hour book time to build a six. They must start the clock with all the shiny parts sitting on the bench, measured and pre-fitted.
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Jake Raby |
Sep 17 2020, 09:51 PM
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#10
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
We always used to laugh about the 40 hour book time to build a six. They must start the clock with all the shiny parts sitting on the bench, measured and pre-fitted. I spent more than 40 hours cleaning my last six.. Attached thumbnail(s) |
BillJ |
Sep 17 2020, 10:06 PM
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#11
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Senior Member Group: Members Posts: 1,078 Joined: 4-March 13 From: charlotte, NC Member No.: 15,610 Region Association: None |
You missed a spot. Lol. That is purty.
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Superhawk996 |
Sep 18 2020, 06:15 AM
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#12
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914 Guru Group: Members Posts: 5,673 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
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Phoenix914 |
Sep 18 2020, 08:45 AM
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#13
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Member Group: Members Posts: 389 Joined: 6-December 06 From: Oviedo, FL Member No.: 7,322 Region Association: South East States |
I started prepping an engine last Friday.When I started, I had previously completed the dynamic balancing, which added another day onto things. Just today I had all the work done for assembly, which will start tomorrow. I don't even keep track of the hours, because I don't bill by the hour. I propose the whole job as a flat cost. The time doesn't matter. This one is a stroker, so that adds one day onto my work, generally speaking. 30 hours for a machine shop sounds about right, IF they are blueprinting the assembly, and also balancing the components, along with the other items that you posted. Today it's a lot more than just building these engines. It's a full restoration effort, at the same time. If you have attention to detail, time to do these tasks can easily dip into the triple digits when it comes to hour count. That's why I don't keep track of it, I don't want to see the fact that I've been doing this for 28 years and I still don't make more than minimum wage. Jake, thanks for your input on this. I added emphasis to your statement above because there was no balancing of components included in the estimate I was given. I'll call the shop again today and talk some more about the overall project. This one is a 2056, so no special clearancing needed. They also might be overestimating so I don't get sticker shock at the end. |
Phoenix914 |
Sep 18 2020, 08:59 AM
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#14
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Member Group: Members Posts: 389 Joined: 6-December 06 From: Oviedo, FL Member No.: 7,322 Region Association: South East States |
Hopefully I didn't imply that. Certainly didn't mean to. I do as much of my own machine work as I can. I have a a sense of what it would take me, but, I'll readily admit I'm not as efficient as a professional machinist that does machine work all day, every day. Even then, I don't have the tooling to do something like a line bore (yet . . .). So may be a bit high, but not outrageous. I'd assume that will run you about $3k in labor. As a benchmark you can look at a Raby engine at $20K and see why he's getting paid that amount . . . all realted to the man hours and machine work that it takes to build an engine like that. You're at $3k and you've only laid the foundation but haven't even put in the man hours to assemble, mock up, check fits and geometry, set up on dyno, run it in, etc. In a mass produced world of cheap labor, it's easy to overlook how long it takes to do things. I do it all the time when I tell my wife it will take an hour and then I spend 3 on any given task. I know what you mean about underestimating time. If days were 8 hours longer, I still would run out! The last thing I want to do with this rebuild is go cheap on prep - or anything really. I plan to buy a camshaft kit from Type 4 store, heads from Len Hoffman, and already have 96mm NPR pistons from the previous (1988!) rebuild. Considering how long it's taken me to get to this point, I don't want to do it twice. It just means I have to work more overtime (IMG:style_emoticons/default/blink.gif) |
Phoenix914 |
Sep 18 2020, 09:02 AM
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#15
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Member Group: Members Posts: 389 Joined: 6-December 06 From: Oviedo, FL Member No.: 7,322 Region Association: South East States |
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Phoenix914 |
Sep 18 2020, 09:21 AM
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#16
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Member Group: Members Posts: 389 Joined: 6-December 06 From: Oviedo, FL Member No.: 7,322 Region Association: South East States |
Just today I had all the work done for assembly, which will start tomorrow. I don't even keep track of the hours, because I don't bill by the hour. I propose the whole job as a flat cost. The time doesn't matter. This one is a stroker, so that adds one day onto my work, generally speaking. And thanks for the picture of all the prepped parts - it gives me an idea of how to lay everthing out for assembly when the time comes (IMG:style_emoticons/default/idea.gif) |
ValcoOscar |
Sep 18 2020, 09:53 AM
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#17
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Garage Life Group: Members Posts: 2,366 Joined: 19-November 13 From: SoCal Member No.: 16,669 Region Association: Southern California |
(IMG:style_emoticons/default/beerchug.gif)
Jake shipped me these two TWIN PLUG engines about 20 yrs ago.... (IMG:style_emoticons/default/aktion035.gif) Oscar |
Phoenix914 |
Sep 18 2020, 09:57 AM
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#18
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Member Group: Members Posts: 389 Joined: 6-December 06 From: Oviedo, FL Member No.: 7,322 Region Association: South East States |
(IMG:style_emoticons/default/beerchug.gif) Jake shipped me these two TWIN PLUG engines about 20 yrs ago.... (IMG:style_emoticons/default/aktion035.gif) Oscar (IMG:style_emoticons/default/drooley.gif) Looks like a big box of candy. |
mepstein |
Sep 18 2020, 10:05 AM
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#19
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914-6 GT in waiting Group: Members Posts: 19,142 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
(IMG:style_emoticons/default/beerchug.gif) Jake shipped me these two TWIN PLUG engines about 20 yrs ago.... (IMG:style_emoticons/default/aktion035.gif) Oscar WOW! |
Jake Raby |
Sep 18 2020, 10:50 AM
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#20
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
(IMG:style_emoticons/default/beerchug.gif) Jake shipped me these two TWIN PLUG engines about 20 yrs ago.... (IMG:style_emoticons/default/aktion035.gif) Oscar Man, that's a blast from the past.. One of them is still going strong, and was sold in a Speedster on BaT a few months ago. I am not sure what happened to the other one, do you know? These were twin plug 2.6L, and the last big bore 103mm engines I built with iron cylinders. We were testing Nickies back then, and didn't have enough time on them to be used in a customer's engine. Fast forward two decades, and I'm still doing them today, here's my current work bench..Now I do these for fun, to make extra coins to buy military vehicles. Attached image(s) |
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