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General Information => Troubleshooting => Topic started by: mtnbob on March 30, 2011, 11:08:08 am
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My 1.6TD is at the machine shop and they are telling me that it still has original standard size pistons in it but that they are going to have to bore it out to .040. They tell me that because of the high wear on the cylinder walls it is too close to bore it out to .020. They tell me that it may be possible to hone it to .020 but that it could take 7-8 hours and will cost a ton due to the time and the fact that it will wear out the honing stones. They also tell me that it won't be as accurate that way. They came highly recommended and have done quite a few VW diesels, I just want to run it by the VW gurus on here and get your thoughts on this. :)
Thank you
Robert
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that sounds like a big load of BS to me...
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so no cutting and straight into the hone? Did they say anything about being out of round or tapering?
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so no cutting and straight into the hone? Did they say anything about being out of round or tapering?
usually a used bore will be out of round, and tapered.. a hone job will not true up the cylinder..
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No, they did not want to hone it at all and discouraged me from that course, but they said that the only way to do it right was to bore to .040 oversize. I asked why they could not bore it out to .020 oversize and they told me that it was too close since it was pretty well worn, and that the only way to get it to .020 was to hone it and they didn't recommend it. Does that sound ok?
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It sounds like they do not know what they are doing. Or they are just lazy. A reputable shop will bore the worst hole until it cleans up and measure that, in order to know what oversize is needed. They are only going to get within .003" or so of the finish bore size anyway with the boring bar and take the rest with a CK-10 Sunnen hone (or equivalent). That is IF they are properly equipped and know what they are doing. Run from any shop that is hand honing their bore jobs, BTW. And make absolutely sure that they understand and follow the directions that come with Kraut pistons. They are a thing unto themselves and are not clearanced nor measured like the rest of the word. All those number on top of the pistons mean things that need to be followed and the pistons are not measured in the same spot as everything else so it is typical to get the bore size to larger than spec w/o realizing it. I have had high miles MB motors that rattled more after the rebuild than before.
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so no cutting and straight into the hone? Did they say anything about being out of round or tapering?
usually a used bore will be out of round, and tapered.. a hone job will not true up the cylinder..
thats a given but I have heard of a couple shops that try to trick you by saying they will save you money etc etc by just doing a hone.
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I've heard of quite a few STD. bore VWD blocks that had to go .040 because .020 wouldn't be enough to make all clean and strait.
And .030 is not an offered piston option for us.
Thats all they are really trying to tell you.
The hone deal was them being overally honest.
It 'could' be done that way with hone stones on a boring bar.
But its not most desirable or most cost effective.
Most of the blocks that can be cleaned and straitened at .020 - are the same blocks that most of us would just normally hone and re-ring STD. ourselves in our own garage.
There has been mention lately of .040 rings being hard to come by for some reason. I didn't read up on all of it. But check into what can be bought - get them in the hands of the shop - then have the boring done. DanCorey was having trouble with .040 stuff in his 83 TD build thread. And someone else.
Another option is re-sleeving to STD. if your pistons are really nice.
But i'd save that for after you wear out the .040 overbore.
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I would go to a different place that has done VW stuff before.
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How many miles/what kind of life did this engine have?? Did they happen to mention what the current measurements are??
Typically a .020 bore will clean em up, but if it's had a rough life (beaten, neglected, grandma'ed, etc) it isn't totally out of the question that it may take an .040 to clean it up... The abortion I've been trying to get together took an .040 bore. with just 200K miles.. The machinist and I batted it back and fourth for some time trying to decide if an .020 was gonna clean it up or not.. Since it's best to have your pistons on hand before boring I just opted to go .040 and be done.. My thinking was that it's going to go at least another 200K (probably much more this time), and by that time TDI's will be dirty cheap... ;D
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That is pretty much what I am thinking. The shop is the best around. And they weren't trying to get more money out of me they were just making what they thought was the best suggestion for the money. I didn't even know that you could re-sleeve the cylinder walls. :o
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That is pretty much what I am thinking. The shop is the best around. And they weren't trying to get more money out of me they were just making what they thought was the best suggestion for the money. I didn't even know that you could re-sleeve the cylinder walls. :o
IIRC they spray weld the sleeves and rebore and hone them.
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What does IIRC mean ???
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google my friend 8)
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IIRC = If I remember/recall correctly
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ok cool ty
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Well....this brings up an interesting point, indeed.
For years, I've quietly sat and read the tales of many of these guys who hone and rering these blocks and then state, "...oh ya...those rings really seated right up and no oil consumption....."
Funny thing...I have YET to see a used VW diesel block/engine come apart and CLEARLY not be out of round and genuinely require a fresh bore and set of pistons. This is on engines I personally ran and those engines which came out of tow-yard or abandoned/otherwise sold cars. And, THAT is either good ol' German cast iron (with a slightly higher nickle content) or not-so-good ol" Brazilian (God only knows what is in there...) cast iron.
Now, have I ever seen one so out-of-round that a 0.020 bore would not cure it's ails.....no. However, I think it is possible.
So....sorry to cast an extremely jaded eye at all of you "ringers" out there....but, I think there are a lot of long noses in the mix!!!!!!!!
EDIT: But, I DO believe it is possible to do a rering and "live." However, I think this needs to be performed "early" before the engine is hard to start or before oil consumption begins to come into play. In other words, while you legitimately still have a round bore to work with. Just me quiet take.....
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Sounds like a good machinist to me.
Mine explained that with very little metal left to remove;
the cutter can skip across the surface.
He has needed to hone to the next size on a couple blocks.
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To agree with Dakota and Fat, I had a hone and rering done to my 1.6 N/A a few years ago. The mech said that I might get 20,000 miles out of it, I might get 50,000. I am approaching 50,000 right now. ;D But it wasn't that bad when it was honed, and I used good rings.
And that is what they were basically saying at the machine shop about the lack of material left to do a proper bore if I tried to do a .020 overbore, I just wasn't sure how to explain what they told me. I feel better about the whole thing after hearing from a few of you, thanks. 8)
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Your sins are forgiven, my son. For panance say one Lord's prayer and........
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........I have to finish this rebuild by Christmas, so I can start on my 1.6 N/A rebuild ;D
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Bob, i forgot what this TD engine is going into ?
And is it Mech or Hyd ?
Is it the one you got from Ontario ?
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Yes it is the one i picked up from Tyler before he moved. Hydraulic head and head gasket looks almost like new, but the block looks like someone tried to just re-ring it and wore it out pretty good. It still had the stock size pistons in it when I got it. Awesome deal from Tyler BTW! He told me that I was taking my chances when I got it, and it is at least better than I expected ;D
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BTW this is what I bought last night 8) Not sure if I got it completely right, but it is a good start, and I couldn't beat the prices :o
KS Piston .040 OS w/Rings Item Number: VOL017560 4 $66.80 $267.21
CRP Oil Cooler O-Ring Item Number: VWW063734 1 $1.56 $1.56
Reinz Complete Engine Gasket Set Item Number: VWW008677 1 $52.56 $52.56
Elring Intermediate Shaft O-Ring Item Number: VWW004170 1 $0.96 $0.96
Mahle Air Filter Item Number: VWW089015 1 $5.81 $5.81
Meyle Fuel Filter Item Number: VWW082475 1 $11.40 $11.40
Mahle Oil Filter Item Number: VWW088971 1 $5.03 $5.03
Febi Flywheel Bolt Item Number: VWW042982 6 $1.63 $9.77
Febi Crankshaft Bolt Item Number: VWW047774 1 $1.72 $1.72
Glyco Main Bearing Set Item Number: VWW065914 1 $38.09 $38.09
Glyco Main Bearing Thrust Washer Set Item Number: VWW065916 1 $12.66 $12.66
Mahle Piston Pin Bushing Item Number: VWW008715 4 $3.07 $12.28
Mahle Rod Bearing Set Item Number: VWW048040 1 $11.24 $11.24
Meyle Freeze Plug Item Number: VWW079736 4 $0.46 $1.85
Reinz Cylinder Head Gasket Item Number: VWW008601 1 $25.18 $25.18
CRP Operating Shaft Seal Item Number: VWW056004 1 $1.18 $1.18
Sachs Clutch Kit Item Number: VWW055678 1 $86.08 $86.08
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You probably should have waited until you had the pistons installed and where able to measure the protrusion before ordering the head gasket.. If that's the 3 notch gasket you'll be okay as far as clearance but you'll have slightly less than optimum combustion going on.. IN all honesty, with a fresh engine you'll probably never notice, but just for the sake of knowing, measure the piston protrusion before putting the head on...
Otherwise the list looks good, 'cept you're forgetting the Giles pump on that list.. ;)
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Hmmmm I went with the same size head gasket as what was on there, a 2 notch. I have a Giles pump on my N/A motor and I love it, but I have a td pump that is supposed to be useable. We will see how it goes and what is left of my budget after all this stuff I am rounding up. Gotta see if I can get this Turbo cleaned up too!!!
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Measure to be sure.. You got a 1 of 3 chance it'll be right.. ;D Typically having the block surfaced is what changes this, but the new pistons could be a tad different and change it one way or the other as well.. From experience I've never had it happen, even with the prothe pistons, but valves smacking those shiny new pistons would suck....
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Thank you for the heads up. I am replacing original pistons with Kolberschmidts(spelling?) and not doing anything to the head at all. It was beautiful, no cracks between the valves, and looked like new.
http://www.flickr.com/photos/11904434@N05/5010545314/in/set-72157624712966321/
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Now, have I ever seen one so out-of-round that a 0.020 bore would not cure it's ails.....no. However, I think it is possible.
So....sorry to cast an extremely jaded eye at all of you "ringers" out there....but, I think there are a lot of long noses in the mix!!!!!!!!
EDIT: But, I DO believe it is possible to do a rering and "live." However, I think this needs to be performed "early" before the engine is hard to start or before oil consumption begins to come into play. In other words, while you legitimately still have a round bore to work with. Just me quiet take.....
Experience would suggest otherwise. I have ringed about 25 NA rabbit diesel engines and a smattering of 5000s and a couple of TDs. Every one that did not get wrecked by the next owner was doing just fine with reasonable oil consumption at 100K. Cast iron rings are just begining to have the compression drop off at that point. As long as the bore is just worn and not pitted or scratched too badly this is just a non problem. It does take reaming the ridge and a careful hone but not much else. That being said I have seen a couple of blocks that had clearly been run without air filters and had badly worn bores that made reringing a poor idea.
FWIW I have probably done 100 ring jobs on various vehicles and the only one with oil consumption problems is my '86 Ranger TD that has a goofy tapered compression ring on top and the ring lands appeared to be a bit worn. At least the new rings were pretty sloppy. The next one that I do will likely have the top ring lands cut for straight rings. (AFIK oversize pistons are not available for these)
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I put new pistons in my block,.. put it all together,.. just to find they didn't stick up high enough.
Had to take it all back apart and have them deck it.
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Yeah, my pistons were on the low side for 1 notch gasket. It is almost like they are planning for you to deck it and want to give you room.