dieseldoc Posted October 24, 2009 Share Posted October 24, 2009 Had a customer ask me today if the newer 7.3 came with powdered metal rods. I honestly had to tell him I did not know for sure. However I was reading through the coffee table books and can not find mention of it anywhere. Anybody know for sure? Another theoretical question here. Customer has a 95 f350 with a 7.3 that is ready for overhaul. He got excited and bought an engine off of craigslist or something. The engine only has 20,000 miles on it and he wants to put this engine in the truck and came to me to put it in. Here is where it gets interesting folks, the engine is out of an 02 f-250. I know the injectors, low pressure fuel system, turbo, HEUI pump, cam is different. Will the base engine(block, crank, pistons, rods, heads) etc work? My thought is the block wont work unless we put an electric transfer pump on it. Or did he make a big oops. I really wish he had talked to me first before he shelled out 3500 bucks for this motor. Thanks for the opinions guys Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted October 24, 2009 Share Posted October 24, 2009 All 7.3L engines came with forged steel connecting rods. As far as putting that 2002 engine in a 1995 truck it should bolt right in but it is everything else like the harnesses, fuel system, intake system, modules... not sure what the goal is here but it smells like a can of worms to me. Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted October 24, 2009 Share Posted October 24, 2009 PMRs are, indeed, forged rods... I'm not a metallurgist and I don't understand the process.... but I suppose that they can be considered to be "steel"... But I am told that they aren't as strong as their old technology counterparts... From my inadequate standpoint, I understand that PMRs are similar to items made of CGI (compacted graphite iron... is this term familiar?). My research is (at this time) "immature" and I hope I'm not reading too much into some of this stuff... I'm glancing over it without the benefit of time to study it in depth... It was somewhere around 2000 or 2001 that the switch was made FROM forged rods TO forged rods in the 7.3.... After all... iron is cast.... steel is forged... but where does the difference come into play? When does iron become steel? Is iron really cast and is steel really forged? Here is where I play the dumbfuck high school drop out card.... "I dunno"... but I'm curious.... I ain't no engineer and I ain't no metallurgist... but I don't see anyone asking many questions.... A good old cast iron block from the 1950s was something to contend with. It was heavy... you had to make it heavier to make it strong enough... Thin wall castings.... in an effort to make things "better" they engineered the block castings to get more strength from less material... "back in the day" we had cylinders completely surrounded by coolant.... and then, to reduce weight, they discovered that they could "siameze" cylinders... adding strength, eliminating weight. Now... you gotta think about the ductility of iron or the malleability of iron or whatever the fuck you can imagine about iron.... but do NOT think that iron is simple .... some iron is flexible.... some iron ain't.... don't look at me for a university level course. Strong iron ain't flexible and flexible iron ain't strong.... Stew on this for a while... I'm going to a funeral on Saturday... I expect you guys to teach ME a thing or two when I get back... FWIW... in my endeavours I found this and THIS Quote Link to comment Share on other sites More sharing options...
GregH Posted October 24, 2009 Share Posted October 24, 2009 Well, I can't tell you the specifics of when certain engines made the change from one type of connecting rod to another - but I can define some of the terms... Iron is just that - the element Fe, number 26 on the periodic table. It is a flexible solid at room temperature, and is still referred to as iron if the level of impurity is below a certain amount. Steel is a generic term meaning an alloy of iron. Common alloys include the addition of carbon, vanadium, chromium and others. Alloying iron makes the material stronger. It's easiest to think of it this way - solid iron forms it's atoms into a lattice structure, basically cubes all stacked up nice an evenly. Left like this, the material can be deformed easily by sliding these cubes out of their nice, even alignment - much like a stack of child's blocks. These impurities that are added act like pins to hold the lattice stricture together, making it much harder to deform. Both steel and iron can be cast and forged. Casting is a method of creating the basic shape of a part by pouring melted metal into a mold and allowing it to cool. The mold is removed, and the part can be sent on to later production steps to finalize it's shape. The mold can be of a reusable type or non-reusable type. Most parts we are familiar with are cast in sand. One method goes like this: A plastic or wax form in the shape of the final cast is coated in a glue and dipped into sand. The sand covered form is then recoated with glue and dipped again until the layer of sand is built up. The glue is then cured, the sand mold then heated to melt out the form, and the empty sand mold is filled with molten metal and allowed to cool. Then the assembly is shaken to break up the sand, and the finished cast is sent on for more machining. An allowance for shrinkage is calculated when making the original wax or plastic form. Forging is when a part is formed without raising it's temperature above it's melting point. One variation is when a slug of metal is stamped in dies to progrssively shape a part into a rough outline. The shape after forging is not final, but closer than casting. Furthur production steps are required to finalize the part's shape. Powdered metallurgy is similar to forging. Instead of starting with a slug of metal, a quantity of powdered metal is used. This is placed in a mold, and the powder is compressed into it's final shape. The mold is then placed into a sintering furnace, and the powder self welds into a solid piece. The temperature at which the piece is sintered is below the metal's melting point, so the distribution and size of the grains in the metal are not disturbed. Once out of the sintering furnace, very little machining is necessary to finish the piece. Final productiuon steps are required for all these methods. In casting, the shape of the mold can't be very complicated because the pour cannot fill complicated nooks and crannies. In forging, more detail can be put to the piece - but not every detail. Working with powdered metal can return a very detailed piece, and only a few final production steps are typically required - in the case of a connecting rod, only the machining of the journals and cracking the rods are necessary. Each of the three methods have thier costs and benefits. Each method works better with some alloys than others. Each method has a different effect on the grain structure of the metal. Each method has it's own variations, too. Powedered metal is becoming much more common - mostly due to cost. Of the three methods, this one has the least waste material, fewer post-forming steps (and therefore cost), better (and easier) control of final grain structure, and the end results are more reproducable. Hope this gives a little background... Quote Link to comment Share on other sites More sharing options...
GregH Posted October 24, 2009 Share Posted October 24, 2009 Not really 7.3L related, but I couldn't help but think about this bit of absurdity while I was writing the above - http://www.adultswim.com/video/?episodeID=8a2505951ea6dcca011eb6fddf7201e1 The reference to the element mercury had me rolling... It's at the end of the clip... Quote Link to comment Share on other sites More sharing options...
dieseldoc Posted October 24, 2009 Author Share Posted October 24, 2009 I hear ya keith... He came to me with hard starting issue a while back. I checked it all out and found it is just plain wore out. It has 250,000 very hard miles if you know what I mean. The compression is vey low, the blow-by is very high, it consumes about a gallon of oil in 3,000 miles, the injectors are original and I am sure just plain shot. The topper on the cake is the air cleaner lid update was never done. I am sort of surprised it has made it as long as it has. This particualr customer is not a big maintenance guy. I asked him when the last time the oil and fuel filters had been changed response "i dunno" the sticker says 14,000 miles and a year ago. That sounds about right. I digress, I told him it was overhaul time. I explained the options and gave prices for each(this was three months ago). He calls me up and says guess what I have an engine for my pick-up can you put it in? Ugggh.......... Quote Link to comment Share on other sites More sharing options...
blown99 Posted October 25, 2009 Share Posted October 25, 2009 Somewhere around 2001 the 7.3 went to the pmr. The older engines all had forged rods. You can remove a pipe plug in the lower block and check out the rod and be able to tell if it is forged or pmr. (I don't remember the difference in appearance off the tip of my head) There was a topic on this a few years ago on ford truck enthusiast . com. The cams are the same. (all the international trucks used the mechanical fuel pump) Remove the plug in the valley of the engine and install the mechanical fuel pump. Heads are drilled to allow for more mounting bolts of the intake manifold. Intakes have larger hoses than the earlier engines. I am not aware of any block differences that would prevent you from installing the engine. Quote Link to comment Share on other sites More sharing options...
Aaron Posted October 25, 2009 Share Posted October 25, 2009 If I was a bettin' man, I'd bet the PMR has a split (read: uneven parting line) cap instead of a smooth machined cap. At least that's how things go on the GM smallblock. Quote Link to comment Share on other sites More sharing options...
Buddy_M Posted October 25, 2009 Share Posted October 25, 2009 Yep, PMR's are cracked whereas the forged are the smooth machined cap. The PMR's also use a bolt threaded into the connecting rod, and the forged use the nut & bolt to retain them together. Pictures of rod differences Quote Link to comment Share on other sites More sharing options...
Buddy_M Posted October 25, 2009 Share Posted October 25, 2009 Quote: The cams are the same. (all the international trucks used the mechanical fuel pump) Remove the plug in the valley of the engine and install the mechanical fuel pump. Heads are drilled to allow for more mounting bolts of the intake manifold. Intakes have larger hoses than the earlier engines. I am not aware of any block differences that would prevent you from installing the engine. Are you sure the cams are the same? IIRC, and I can check later when I go to my shop, I have a bad cam out of a 01 engine from a few years ago and it did not have the lobe for the fuel pump , and I thought that where the fuel pump went is now casted solid with the block, so there is no provision to remove the plug and install one. As for the intakes, certain 99MY and earlier engines used the 8 bolt intakes, while later engines used the 10 bolt, and I didn't think they were interchangeable without changing the heads due to differences in the bolt patterns? Another thing to think about would be PCM calibration effects on it running, since the existing PCM knows it should have AB code injectors, and the new engine should have AD/AE injectors, and they each have different fuel flow rates. Buddy Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted October 25, 2009 Share Posted October 25, 2009 I think Buddy's right here. There are DEFINITELY different cams, as our local IH dealer put in a reman T444E engine that came with a camshaft from a late 7.3 PSD, without the fuel pump cam lobe. They figgered it out after a couple of fuel pumps. There are definitely injector differences, too. It could probably be made to work, but there's no giving a quote on this one.... Good Luck! Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted October 25, 2009 Share Posted October 25, 2009 Yep, PMR's are cracked whereas the forged are the smooth machined cap. The PMR's also use a bolt threaded into the connecting rod, and the forged use the nut & bolt to retain them together. Pictures of rod differences Good find and info. I was looking in the service manual which made no mention of whether the rods were powdered metal or not, it just says forged. I am sure SOMEWHERE this is stated... I also can't remember the last 7.3L I have had out and apart but I assure you it was before the PMR's were being used. Awesome thread! Quote Link to comment Share on other sites More sharing options...
Buddy_M Posted October 25, 2009 Share Posted October 25, 2009 Keith, when I was in the dealership(wow, about 3 years ago now), the only other place I seen this stated was in the 7.3/diesel engine training in STARS and it listed the serial number break. I have also heard that it was not exact at that serial break, as there were some before that break with PMR's and after with forged. Buddy Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted October 26, 2009 Share Posted October 26, 2009 Not really 7.3L related, but I couldn't help but think about this bit of absurdity while I was writing the above - http://www.adultswim.com/video/?episodeID=8a2505951ea6dcca011eb6fddf7201e1 The reference to the element mercury had me rolling... It's at the end of the clip... Must have something to do with homeland security, Greg... Us lowly Canucks can't partake in any cross border sharing of that video... Quote Link to comment Share on other sites More sharing options...
blown99 Posted October 26, 2009 Share Posted October 26, 2009 I just ran out and checked my own truck, 02 7.3. I have a welsh/freeze plug in the valley of the block where the fuel pump used to go. (not casted over) My quick reference book I have only shows one cam?? Two different part numbers for the heads (depending on the intake bolt configuration). The ecms are different. I have recieved reman 444's with one bank of AB and hte other bank full of AD split shots. Thought the engine was going to jump out of the frame rails when it actually started, so yes the programming is diffrent between the two. Quote Link to comment Share on other sites More sharing options...
dieseldoc Posted October 26, 2009 Author Share Posted October 26, 2009 According to the coffee table book the lobe was eliminated in the 99 and up. To bad about the heads being different. This can of worms is most likely best left unopened. I have a correct 7.3 core at my shop, My best bet may be to offer a good deal on that engine and buy the one he just picked up. A buddy of mine has 02 with alot of miles that will need this engine sooner rather than later. I am glad I asked this question I have learned alot about these elusive powder metal rods. You would think there would be mention of it in the coffee table book or information only tsb or something. Especially if the powder metal rods are a fractured rod. Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted October 26, 2009 Share Posted October 26, 2009 Before anyone get's too carried away... let's remember that there isn't any apparent reason to get worried about having the PMRs.... unless you're dealing with power adders - once you get into that, all bets are off. I'm almost sure that there was some trepidation when the switch to PMRs was mandated... CGI engine blocks are one of the next logical steps in evolution.... consideration - a diesel engine with aluminium heads - does a CGI block offer better thermal compatability with the heads? Installing aluminium heads on an iron block introduces sealing nightmares.... installing aluminium heads onto something with 17 to 20something to one compression ratio and then adding forced induction.... One would think that the engineers have their bases covered... but why are my toes curling even before the engine reaches the street? Factoid.... I am unsure about modern practice. In the past, even the best engine blocks that Kieth Black and Ed Pink had to offer would have the water jackets filled with grout to add strength in fuel applications. (The last number I heard placed fuel consumption at 65ish gallons per minute) At this point in history (each moment we exist is doomed to become history very soon) the engineers have a pretty good handle on "!?@#%!'s !?@#%! and that's that". As long as we don't step outside of design parameters - either by design (a power adder) or by accident (a stuck VGT turbo in a modern engine)... we should be OK. But.... all the testing in the world (especially when it is done by folks that know engines) can't approach what the guy that lives down the street can do in the way of abuse... How many bottle rockets must a youngster try launching from the crack of their ass before they realize that God made Cape Canaveral for a reason? Quote Link to comment Share on other sites More sharing options...
Adam_Dodson Posted October 26, 2009 Share Posted October 26, 2009 Installing aluminium heads on an iron block introduces sealing nightmares.... installing aluminium heads onto something with 17 to 20something to one compression ratio and then adding forced induction.... One would think that the engineers have their bases covered... but why are my toes curling even before the engine reaches the street? The D-MAX has been using aliminum heads since 01, and with much less head gasket leaks then the 6.0. Have faith Jim! Quote Link to comment Share on other sites More sharing options...
Aaron Posted October 26, 2009 Share Posted October 26, 2009 You can't keep injectors in a duramax long enough to blow it up Quote Link to comment Share on other sites More sharing options...
Adam_Dodson Posted October 27, 2009 Share Posted October 27, 2009 oh i forgot how awesome the 6.0 injectors are Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted October 28, 2009 Share Posted October 28, 2009 Let's see... CGI block = lighter and stiffer = higher thermal loading per pound.... Old engines built with a bazillion pounds of old school, flexible cast iron could absorb thermal loads that would destroy a modern engine.. Newer engines have operating strategies designed to ameliorate cooling system failures. Let's call this one even. The 6.7 will have one extra head bolt per cylinder... I don't know where and I can't remember what the bolt diameters are... bolt length plays into the equation, too... Some 396 and early 427 "rat motors' had head gasket problems at as low as 11.5:1 static CR... these motors had 5 bolts per cylinder - two sharing... Staking the block deck around the short bolts seemed to help... and remember that these weren't TTY bolts (workshop manuals of the day recommended replacing headbolts after the second use). An extra head bolt you say? FWIW the 427 SOHC used 4 bolts per cylinder and 11:1 or 12:1 compression was ho-hum... I'm pretty sure some NASCAR teams were dancing with 13:1 before Bill Sr yanked the rug out from under the Hemi and the Cammer and cut the balls out of the rat. Mind you, the Boss 429 was likely the real catalyst in the move to sub 360 engines... and the Boss 429? Yep - 4 per cylinder - two sharing. Having faith is for you youngsters.... I've been a motorhead since I was "knee high to a grasshopper".... "Show me the time slip"... I hope the engineers prove me wrong... there ain't many people more "Ford" than I am.. But I've been around enough years to know that even modern day testing will fail to appreciate the stupidity of it's customers and the opportunity for failures to happen... One of the 6.0s biggest detriments is the lack of a waste gate. The VGT sticks - bye-bye head gaskets... The 6.7 appears to have a waste gate... a poor substitute for a positive VGT position controller/failure strategy... but better than what we had... Score one for the 6.7 Speaking of turbo.... ever watch heavy equipment working at night? Those with exposed turbochargers are.... nifty looking. While we need to keep an eye on the dirtymax.... it is the PSD that concerns us.... No sense in worrying about the chinese restaraunt if you are selling pizza... Quote Link to comment Share on other sites More sharing options...
Aaron Posted October 30, 2009 Share Posted October 30, 2009 I like Pizza. Quote Link to comment Share on other sites More sharing options...
LARRY BRUDZYNSKI Posted October 30, 2009 Share Posted October 30, 2009 I like Pizza. And Beer Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted October 31, 2009 Share Posted October 31, 2009 Originally Posted By: Aaron I like Pizza. And Beer So... are you guys done talking about basic food groups? Quote Link to comment Share on other sites More sharing options...
Aaron Posted October 31, 2009 Share Posted October 31, 2009 I don't like Chinese food. Quote Link to comment Share on other sites More sharing options...
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