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Discussion Starter · #122 ·
Would the repair sleeve be the same between the 3.9 and the 4.5? I tried surfing through Quickserve but I couldn't find a complete parts list. Going to their new parts website didn't return a whole lot either.

Seems like the most common sleeve is 3904166. The bore is right, but the length is the part that makes me worried.
 

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Good question. I see no reference to a repair sleeve on the specs for the engine block. In having been around shops that did that kind of work, the sleeve is normally a good bit longer than necessary. If I remember correctly, the 4.5 block deck is about 1/2" taller than the 3.9. Might drop Cummins an email inquiry and see what they say. Interesting that 3904166 from Cummins is around $120 and aftermarket replacements are around $20. Bit of price mark up there. LOL.
 

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Discussion Starter · #124 ·
Good question. I see no reference to a repair sleeve on the specs for the engine block. In having been around shops that did that kind of work, the sleeve is normally a good bit longer than necessary. If I remember correctly, the 4.5 block deck is about 1/2" taller than the 3.9. Might drop Cummins an email inquiry and see what they say. Interesting that 3904166 from Cummins is around $120 and aftermarket replacements are around $20. Bit of price mark up there. LOL.
Good idea asking Cummins. The stroke from a regular 4BT is 4.72" and on the 4.5 it is 5.39". We are talking about 2/3 of an inch in increased stroke. I will also call my machine shop and see what they think.

And to talk about the deck height, the push rods are not any longer than a regular 5.9 or 3.9. I have a bunch of them laying around. The rods are longer for sure and the crank is different. I believe that all Cummins did is increase the stroke by drawing it down farther in the cylinder, not adding it up top. Referencing this thread: Cummins QSB4.5 liter 4cyl???. Lots of loose ends on this engine.
 

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Interesting, the push rods are the same so that would indicate the block height should be the same as a regular 4bt. However, the 4.5 block has the following part numbers 3938366, 4089546, and newest number 5406591. Those numbers do not appear on any other 4bt engine which tell me there's something different about those blocks. Could it be possible instead of raising the deck height they lowered the crank location. They could also have moved the pin location in the pistons. These engines are just weird.
 

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Discussion Starter · #126 ·
Interesting, the push rods are the same so that would indicate the block height should be the same as a regular 4bt. However, the 4.5 block has the following part numbers 3938366, 4089546, and newest number 5406591. Those numbers do not appear on any other 4bt engine which tell me there's something different about those blocks. Could it be possible instead of raising the deck height they lowered the crank location. They could also have moved the pin location in the pistons. These engines are just weird.
Could be that, or the fact that these are similar to the STORM blocks that have different threads for oil galleys and stuff. They are definitely an abberation. Even the naming convention...you say QSB and people lose their minds when you tell them there is an 8 Valve QSB in existence. When I get it back from the machine shop, I will take some measurements.
 

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Discussion Starter · #127 ·
Here is the update: Machinist and I had a cross up. I am kind of frustrated over it, but nothing to do about it now except to proceed. I was under the impression that I was going to have the whole block sleeved but wound up getting one sleeve (cylinder 3) and he punched all holes out to .040 over/1mm over. That made it much more difficult to find pistons. This is only an issue because the 4.5 is pretty unique. So that's the story. He is waiting on me to get my new pistons so he can do the finish boring.

And of course, because it is more difficult to get those pistons, it is now taking 2-3 weeks for a kit to be assembled. I went to Heavy Duty Pros to get the kit assembled. I am doing the full Engine Overhaul kit and it wasn't cheap. $880 with tax, shipped.

Good news is my crank is still good everywhere and a polish should take care of it. I am going to bring the rods, wrist pins and new bushings in so they can be bored to size. I will be assembling everything else myself. Never done it, but I can follow directions well enough. I hope. Ha! I would imagine in a couple more weeks I will have everything back so I can get it thrown together.
 

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You didn't get hurt on the rebuilt kit price. The .040 over piston kit is part 4089621 and Cummins sells them for $289.71 each. So that would have been $1158.84 for the pistons and rings. Actual kits are 1.00mm overbore which is just a tad smaller than .040". Gasket sets for that engine are parts 3802375 lower for $475.47 and 4089648 upper for $296.33. So by the time you get the other tidbits such as bearings, etc. you'd be over $2000 in factory parts.
 

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Discussion Starter · #131 ·
Pistons are with the machinist and that means that he is going to get it sized completely. Then he is going to get the crank polished up as much as he can. I don't want him to turn it if possible. This isn't a race engine. I just want it functional.

One small issue I am having is that I need to replace at least one wrist pin bushing and he doesn't have the tooling to press out and press in the new tapered bushings. So I am going to have to figure something out there...
 

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Discussion Starter · #132 ·
I picked up the block and crank from the machinist on Friday. All looked good. Cost me $712 bucks to have one cylinder sleeved, bore all out 0.040, deck the head, polish the crank. I have no idea if that's a good price, but it is what it is.

To that end, I started on assembly. I popped out the old cam bushing and put the new one in. Really rather simple operation. I hesitated at first, but threw caution to the wind and went after it.

Then I moved on to the crank caps. Grabbed me some Lubriplate 105 and got everything nice and greasy. The manual I was using said to torque the feller to 44, 88 and 130 lbs. All the bolts took 44 and 88 no problems. Apparently, that doesn't work for this later set of bolts for this engine because I snapped the ever loving crap out of the middle cap's 2nd bolt. The good news is that it came right out no issue because it stretched in the middle and that's all she wrote.

So I guess I need some advice here. Should I be getting some 23mm bolts instead of the 18mm bolts and go back to the torque sequence above?
 

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Never heard of anyone having much issue with the crank cap bolts. Cummins doesn't recommend replacing those. Now the head bolts which are smaller are another animal. Are you sure of those torque numbers? A regular 4bt shows 44 lb ft, 66 lb ft, and then turn them 90 deg. However, there seems to be some discrepancy as to those numbers. Found another source that only shows a single step for a Cummins B series at 130 lb ft. Now the ISB and QSB engines show the multi step but I believe that is for the common rail block, not the style you have. Is that manual you have specifically for the QSB4.5-30 engine. The other QSB4.5 engines are a different block. You mention those bolts are 18mm. Was that the hex head size? According to Cummins they are M12x1.50x119mm Fracture Resistant Screw. Cummins part number 3927948.
 

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Discussion Starter · #134 ·
Never heard of anyone having much issue with the crank cap bolts. Cummins doesn't recommend replacing those. Now the head bolts which are smaller are another animal. Are you sure of those torque numbers? A regular 4bt shows 44 lb ft, 66 lb ft, and then turn them 90 deg. However, there seems to be some discrepancy as to those numbers. Found another source that only shows a single step for a Cummins B series at 130 lb ft. Now the ISB and QSB engines show the multi step but I believe that is for the common rail block, not the style you have. Is that manual you have specifically for the QSB4.5-30 engine. The other QSB4.5 engines are a different block. You mention those bolts are 18mm. Was that the hex head size? According to Cummins they are M12x1.50x119mm Fracture Resistant Screw. Cummins part number 3927948.
Well, the torque numbers came out of an Army manual for the All Terrain Crane which had a 6bt. "B Series, Shop Manual, 1991 and 1994, Certification Levels". That might be the issue. Or part of it anyway. I only have the Owners Manual fro the QSB4.5 and QSB6.7 and that's not even for my engine nor does it have anything other than basic maintenance. I am going to delete it. These engines are as rare as hen's teeth so getting any info is not fun!

As far as the 18mm, I was referring to the bolt head size. The manual called out 23mm. And I do have a set of those bolts from a 6bt I could use. But it kind of makes me nervous.

Are the service manuals on Quickserve? I do have my esn in Quickserve so that's useful for parts.
 

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Those QSB engines in that manual are the common rail units and have a different block that yours. Here is one listing for the manual on your engine. Cummins QSB3.9-30 / QSB4.5-30 / QSB5.9-30 Manual - Foley Engines It isn't cheap but I wouldn't expect it to be. I believe the Cummins part number for that manual is 4021398. If you go on Quick Serve, it shows a price of $82.50. Heck of a lot better than $125 which most sell it for.
 

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Discussion Starter · #136 ·
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