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THINKING OF ENGINE REBUILD SOON

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Old 12-06-2010, 07:15 PM
  #61  
Landseer
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You only live once. Practice your hobby, where you get enjoyment, at whatever level suits you.

Last edited by Landseer; 12-06-2010 at 08:50 PM.
Old 12-06-2010, 07:27 PM
  #62  
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Originally Posted by Rob Edwards
We do indeed, Luan. I am definitely guilty of putting parts up on the shelf for a rainy day! Parts prices aren't going to get any cheaper....

That said, I have to say that with all the stuff you've done in the last year or two (outlined in post #43) that I wouldn't be pulling that engine any time soon. The short block just doesn't need attention at 150K miles. You've already replaced everything that can be rebuilt with the engine in place!
Yeah, everyone here seems to think that these are "special engines" that last forever and ever. Ignore the fact that it has turned a minimum of 565,000,000 revolutions. Pretend that it is made from some sort of uber unobtainium metal and things never wear out, like in every other engine on earth.

Wait until something actually breaks...so you can then try and find a "matching number" engine block for your GT!

And when you do finally rebuild it, after God only knows how long...make sure you reuse all the gaskets and seals....

Look guys...some of these engines might go 200,000 miles...but the majority don't make it that long....and if you have an engine that is virtually irreplaceable...150,000 miles is probably enough.
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Old 12-06-2010, 07:40 PM
  #63  
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shhhhhhsh! my motor is going to hear you!

Originally Posted by GregBBRD
Yeah, everyone here seems to think that these are "special engines" that last forever and ever. Ignore the fact that it has turned a minimum of 565,000,000 revolutions. Pretend that it is made from some sort of uber unobtainium metal and things never wear out, like in every other engine on earth.

Wait until something actually breaks...so you can then try and find a "matching number" engine block for your GT!

And when you do finally rebuild it, after God only knows how long...make sure you reuse all the gaskets and seals....

Look guys...some of these engines might go 200,000 miles...but the majority don't make it that long....and if you have an engine that is virtually irreplaceable...150,000 miles is probably enough.
Old 12-06-2010, 08:37 PM
  #64  
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Originally Posted by GregBBRD
And those parts look like they are a list of the cheapest prices around. Getting a reputible shop to put an engine together without their profit margin on the parts is going to be very difficult to find. I've done it a few times and my accountant tells me I'm literally loosing money on those jobs....might as well give the customer a wad of money, when they first walk in, and send them away. That, my accountant claims, would be cheaper, for me.

The math is actually pretty damn easy. It costs me about $1000 a day to unlock the front door on the shop and turn on the lights. If I charge $120.00 an hour and work 8 hours....at the end of the day, I've lost $40.00, if I don't make money on parts!

Interestingly enough, as my shop and reputation has evolved...I find myself doing more diagostic operations on vehicles (that other shops can't seem to repair). When I do diagnostics, there is no profit margin on parts....so I end up loosing money, as I trace down people's nagging problems....and that is only if I actually charge for all the time it takes to diagnosis things...which is very hard to do.

A very recent example:

I just got down tracing down and repairing a miss-fire on an '86 928. It was a complex problem. It had low compression on all the cylinders connected to the left distributor cap. I replaced the coil, cap, coil wire, and rotor...all of which had visual issues. Replaced the spark plugs, when we did the compression test. We replaced the original spark plug wires (with the customer's supplied wires). Still missed. Installed a rebuilt airflow meter and replaced the "dead"
O2 sensor. We them "carbon cleaned" the engine to remove carbon and clean the injectors. Still missed, in the exhaust, but now ran on all 8 cylinders consistantly. The compression was improved. The next step was to pull off as much of the intake as we needed to repair 6 separate intake leaks. Put it all back together, reset the fuel mixture, and...it still missed, through the exhaust. We finally did a complete check on the injection system and found that the TPS was dead...along with the short wire going to it. Pulled the intake back apart and removed the throttle body and replaced the switch and the pigtail to it. Put it all back together, reset the fuel misture (again), and it finally ran great. No possible way to bill for the 4 days of work this took....so, in the end, I ended up billing for only part of the effort. Even so, the bill seemed stupid....$2800 in parts and labor...and he supplied the spark plug wires!

I sat down, this Saturday, and figured this all out. I literally lost $1,400.00 doing this job. When the car came in the shop, I could have handed the guy $1000.00, sent him away, gone out and sat in the sun for 4 days, and I would have been $400.00 ahead! WTF?

Back to the internet parts problem:

I asked around, a few weeks ago at a bunch of shops, and asked how they handle the "internet parts issue" ("I have my own parts and want you to use them, on my repair"). The results of my informal survey were very interesting. Most all shops refuse to use anything they don't supply. I did find two shops that allow people to bring in their own pieces, but they add on the percentage that they would have made on the parts, directly to the bill. Of course, they can't warranty any of the customer's own pieces, so that pretty much defeats any logical reason for the customer to bring the pieces in, in the first place.

I found no one that would take a big box of parts and install them. The general consensus was that the people that get their parts from the internet had better be prepared to install those pieces, themselves.

Most all of the shop owners that I talked to explained it like this:

"When I go out to dinner....I don't bring my own steak and ask them to cook it, serve it to me, and then only charge for the labor of doing that."

Actually, some restuarants will allow you to bring your own bottle of wine...but they charge you a "corkage fee"....even if you open it and serve it yourself. Note that if your bottle of wine sucks...they still bill you the "corkage fee".

So, the shop owners that add their profit margin into the bill when people bring in their own parts perhaps are not all that stupid. They are just adding a "corkage fee".

I know this:

Something has to change, at my shop. Working on old 928's is challenging and interesting. It is not very profitable. I could literally, for the past several years, worked at Home Depot and made more money! And my wife would not have had to been there to run the office...for nothing!

First, a lot of shop cut down their operating cost by having many mechanics. Last shop I went to had 5 mechanics working full time... and yet they charged 68$ per hours! (The job was good too)

As for cash off parts... I agree, and desagree. If you are making cash off your parts, it's maybe the rest of your shop isn't balancing out correctly. I know every shop make cash off the parts. But I'm kinda against that. Charge me more per hour, but leave the parts alone. How is the people suppose to know how a part really cost if some shops do a x2 or x3 on the cost? If I get charge 300$ for a bearing, but on the net I get the same for 100$? Of course, as a client, I feel cheated seeing that. I paid for what? The guy pressing a button on his computer to get the part? He may had it in inventory!

As for internet parts... Our 928 offer a special problem. There's some part that are not made by any real supplier anymore! What am I supposed to do with an engine harness? Find someone that would help outside a real shop?
- Hey! I would like you to change my engine harness.
- Sorry, we can't get that part off our chain of supplier.
- Ok... I got a specialist who can make a new one.
- Sorry, it's not a part from us or our supplier, we can't install it.
/facepalm
In the end, with that harness, I needed the help of a real shop as I had wire problem between the inside of the car and the harness plug. Unlike you, the mechanic had no problem charging me for the 10 hours he passed poking around to find the problem, and seriously, I don't mind since the job was well described, problem found well explained and solution well made. He pointed me the stuff that would need to be changed with real parts later. It's all clear, and I'm happy.

I can't stand shop that their bill is like "Change a part... 20 hours... 2000$". Doesn't take a day to write a real list of work done and explain exactly what was done.

If you worked 4 days on a car, charge 4 days.

But don't work 4 days like that changing random part! Communication! I love when a mechanic call me and explain me exactly what's happening, why, where. Here, the law requires the mechanic to get approbation from the client before any parts are changed. Of course, I've meet lot of mechanic who don't give a f***. And in the end, they all gave me terrible work result at terribly high price. (And surprise, the Porsche dealer/mechanic was one of the worst. 300$ for NOT doing a job.)

But I'm no mechanic... Just my 2 cents from a guy who had terrible and amazing mechanics.
Old 12-06-2010, 11:09 PM
  #65  
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Originally Posted by LightStriker
First, a lot of shop cut down their operating cost by having many mechanics. Last shop I went to had 5 mechanics working full time... and yet they charged 68$ per hours! (The job was good too)

As for cash off parts... I agree, and desagree. If you are making cash off your parts, it's maybe the rest of your shop isn't balancing out correctly. I know every shop make cash off the parts. But I'm kinda against that. Charge me more per hour, but leave the parts alone. How is the people suppose to know how a part really cost if some shops do a x2 or x3 on the cost? If I get charge 300$ for a bearing, but on the net I get the same for 100$? Of course, as a client, I feel cheated seeing that. I paid for what? The guy pressing a button on his computer to get the part? He may had it in inventory!

As for internet parts... Our 928 offer a special problem. There's some part that are not made by any real supplier anymore! What am I supposed to do with an engine harness? Find someone that would help outside a real shop?
- Hey! I would like you to change my engine harness.
- Sorry, we can't get that part off our chain of supplier.
- Ok... I got a specialist who can make a new one.
- Sorry, it's not a part from us or our supplier, we can't install it.
/facepalm
In the end, with that harness, I needed the help of a real shop as I had wire problem between the inside of the car and the harness plug. Unlike you, the mechanic had no problem charging me for the 10 hours he passed poking around to find the problem, and seriously, I don't mind since the job was well described, problem found well explained and solution well made. He pointed me the stuff that would need to be changed with real parts later. It's all clear, and I'm happy.

I can't stand shop that their bill is like "Change a part... 20 hours... 2000$". Doesn't take a day to write a real list of work done and explain exactly what was done.

If you worked 4 days on a car, charge 4 days.

But don't work 4 days like that changing random part! Communication! I love when a mechanic call me and explain me exactly what's happening, why, where. Here, the law requires the mechanic to get approbation from the client before any parts are changed. Of course, I've meet lot of mechanic who don't give a f***. And in the end, they all gave me terrible work result at terribly high price. (And surprise, the Porsche dealer/mechanic was one of the worst. 300$ for NOT doing a job.)

But I'm no mechanic... Just my 2 cents from a guy who had terrible and amazing mechanics.
I always make sure that the customer knows why parts were replaced, but when you are dealing with a electrical issue, you can show them where the problem was, little harder to explain why it took you ten hours to find it, or why you can not give a quote to fix it.

I guess it really does not matter though, nobody in a sound frame of mind wakes up one day and says to himself "I think I am going to open a auto repair shop today" the ones that do that, don't last long.
Old 04-10-2011, 12:45 AM
  #66  
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Default CYLINDER WALL HAVE SCRATCHES

Getting ready to do a rebuild,well got the block back after honing and cleaning, crank polishing-oil fitting issue fixed to discovered that several of the cylinder wall have scratches-would that impede the the rebuild on this spare block? Martin will probably chime in on this as we will post picts soon-still have orig block in car and will have to pull engine to re-use the the later head....
Old 04-10-2011, 01:23 AM
  #67  
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Originally Posted by RED SHARK 1990
Getting ready to do a rebuild,well got the block back after honing and cleaning, crank polishing-oil fitting issue fixed to discovered that several of the cylinder wall have scratches-would that impede the the rebuild on this spare block? Martin will probably chime in on this as we will post picts soon-still have orig block in car and will have to pull engine to re-use the the later head....
tell us more.
Old 04-10-2011, 02:27 AM
  #68  
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I hope you misunderstood "honing". I took apart a 928 motor that had very low compression and high leakdown to find that the cylinders had been honed like an iron block on a recent rebuild. Anyway, I think you misunderstood that.

I just read GB's comments that these motors usually don't make it to 200k miles, although a few limp along beyond that, so that's awfully good support for your efforts. I've never heard him say that before, and I've been in the camp that thinks these motors are more durable than that if you can avoid doing a few horrible things to them. I know of some wear parts that are likely enough to give out before then that I would replace, but they don't require a motor overhaul. I'm thinking cam chain tensioner blocks, main seals, oil pump seals, valve guides and seals, maybe rod bearings, but after that I'm not sure what else, other than more routine maintenance parts like the cam gears. I don't believe in driving a car till it conks out, but at 230K miles currently, I'm still not seeing a reason to tear the motor out of my 89. I pulled the cam covers and did the tensioner blocks and checked the oil feed plugs a while back, I did a rear main seal when it leaked, but that's about it in terms of the motor. It gets prescribed maintenance, driven almost everyday, stored indoors, still has excellent compression and very low leakdown, and the motor still runs at least as well as the day I bought it 11 years ago. Maybe it's living on borrowed time and I'm about to learn an expensive lesson. I'll have to think more about this. Up until now, I've been pretty comfortable with the condition of the motor.
Old 04-10-2011, 02:53 AM
  #69  
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Engine block cleaned, checked, cylinder bores "honed". obviously not like standard steel liners. motorworks here in SD are experienced and understand the alusil process. there are two parrellel lines, one in each cylinder (#6 and #8). they did not seem so obvious before machine work. they just catch your finger nail towards the top of the cylinder. i'll get some pictures up tomorrow. i believe most everyone would run it as is. not many choices anyhow
Old 04-10-2011, 03:16 AM
  #70  
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Originally Posted by Bill Ball
I'll have to think more about this. Up until now, I've been pretty comfortable with the condition of the motor.
+1
I'm going to call my mother first thing in the morning and warn her not to drive her 160k mile Jaguar 1997 XK8 anymore, it might spontaniously combust at any moment. She hasn't even had the timing chains inspected since purchasing the car with 60k!!!!

I can only image what's really going on inside my 200,000+ mile Audi Quattro that I take up to 7,000rpm as often as I can every time I drive it, even in snow storms.

Dear lord, I better park my entire fleet now and go buy a new Kia. Here I thought all this time German cars were a bit better than the domestic options like the 1991 Caddy I sold with 225k on the odo that would still burn the tires off the line and average 34mpg down the highway. What was I thinking.......

I'm sitting her next to Jim Page who is now paranoid about driving his 1996 Suburban home that still has the original water pump at 170,000 miles. Most of those miles were used as a vehicle tow vehicle, it's a basic 3/4 ton.

He's now reminiscing about the SAAB his customer purchased new and drove to 325,000 miles with the oringal timing chain before donating it (still running) to charity. That guy should have bought a lottery ticket.
Old 04-10-2011, 03:16 AM
  #71  
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Originally Posted by Shark_Week
Engine block cleaned, checked, cylinder bores "honed". obviously not like standard steel liners. motorworks here in SD are experienced and understand the alusil process. there are two parrellel lines, one in each cylinder (#6 and #8). they did not seem so obvious before machine work. they just catch your finger nail towards the top of the cylinder. i'll get some pictures up tomorrow. i believe most everyone would run it as is. not many choices anyhow
Answers my questions, sounds like you have a handle on it.
Old 04-10-2011, 03:21 AM
  #72  
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Yeah, I expect to see "lapping" (with felt and silicone paste) rather than "honing", and even that only after machining because it requires so much setup. Reading "honing" scared me just a bit.
Old 04-10-2011, 03:43 AM
  #73  
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There were no lines of any sort on the cylinder walls of this block when I pulled the heads. They were completely smooth, top to bottom. I ran my finger nails on every inch of them. I would find a new machine shop; whatever their reputation.
Old 04-10-2011, 03:50 AM
  #74  
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Originally Posted by Hacker-Pschorr
+1
I'm going to call my mother first thing in the morning and warn her not to drive her 160k mile Jaguar 1997 XK8 anymore, it might spontaniously combust at any moment. She hasn't even had the timing chains inspected since purchasing the car with 60k!!!!

I can only image what's really going on inside my 200,000+ mile Audi Quattro that I take up to 7,000rpm as often as I can every time I drive it, even in snow storms.

Dear lord, I better park my entire fleet now and go buy a new Kia. Here I thought all this time German cars were a bit better than the domestic options like the 1991 Caddy I sold with 225k on the odo that would still burn the tires off the line and average 34mpg down the highway. What was I thinking.......

I'm sitting her next to Jim Page who is now paranoid about driving his 1996 Suburban home that still has the original water pump at 170,000 miles. Most of those miles were used as a vehicle tow vehicle, it's a basic 3/4 ton.

He's now reminiscing about the SAAB his customer purchased new and drove to 325,000 miles with the oringal timing chain before donating it (still running) to charity. That guy should have bought a lottery ticket.
OK, OK! I'm going to replace the whole car.
Old 04-10-2011, 09:30 AM
  #75  
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Luan make absolutely sure to use 3 cans of brake cleaner on the crankshaft after it has been polished,
you will find that there is a lot of polish material inside the oil pathways, if this isnt cleaned out then your engine will self destruct shortly after you fire it up.

the best way to fix this is to remove the oil way plugs and tap and install new plugs after cleaning.

after cleaning then use simple green and very hot water to wash the crank off then spray with WD 40 so it wont rust be generous


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