6.9 IDI Build

My .02. Talk to Hastings, see what their specs are before divulging your measurements and if their not in spec send them back. If they are in their spec run them. The consistency between them seems pretty good so it doesn't seem to be a manufacturing defect.

Dirtleg said:

My .02. Talk to Hastings, see what their specs are before divulging your measurements and if their not in spec send them back. If they are in their spec run them. The consistency between them seems pretty good so it doesn't seem to be a manufacturing defect.

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I could never get anyone to answer at Hastings. Maybe they took the week off for the holidays. I ended up running the oil rings since they were still within the spec. I doubt a few more thousandths will allow any noticable oil past.

I gapped the top ring to .018. I didn't want to use the minimum gap range here because of the cylinders being bored larger and the addition of the turbo. Second ring is at the minimum gap spec of .060. Thats plenty big for anyone's minimum gap.

Plastigauge showed all rod bearing clearnces to be about .002". Side clearance between rod pairs measured from .013 to .015.


Slugs in their new bores.

One thing that I am worried about is that as I was seating the rods onto the crank, the bearing lube kept getting on the machined mating surfaces where the rods and their caps meet together. I didnt see a way to keep them clean while still keeping adequate lube on the rod journals and bearings, so I just let it be. But I feel like if lube is trapped in there that it could add thousandths to the bearing clearance. Or maybe it could eventually work its way out leading to loose rod bolts. I used the red Clevite bearing assembly lube.

WarNose said:

One thing that I am worried about is that as I was seating the rods onto the crank, the bearing lube kept getting on the machined mating surfaces where the rods and their caps meet together. I didnt see a way to keep them clean while still keeping adequate lube on the rod journals and bearings, so I just let it be. But I feel like if lube is trapped in there that it could add thousandths to the bearing clearance. Or maybe it could eventually work its way out leading to loose rod bolts. I used the red Clevite bearing assembly lube.

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Attention to detail makes for a much better build, but don't worry about that. As long as everything torques up you will be fine.

Yep no need to worry about the assembly lube, if you really want to be **** about it you could plastigauge one main cap with no lube then add lube and see how much the tolerance changes, then use the difference to figure out where you want your tolerance to be.

Thanks fellas. That makes me feel a lot better now that you have said that.

Last night I made to solid lifters with washers as @IDIBRONCO had described. For me, four #6 washers at the bottom, in the spring cup, and five #10 washers on top of that, fit just right with the retainer clip barely fitting in.

Today I checked the piston to valve clearance with playdoh. I was nervous about what would happen if contact happened so first I tried without bolting the heads all the way down so they could lift if anything happened. But this doesn't work because the cam will lift the heads before it opens the valve springs. So I then tried with the bolts just snugged down, not compressing the head gasket on one piston. Plenty of clearance at .090 for intake and exhaust. So then I torqued the head down and checked all cylinders. Clearances were kind of all over the place with the intake ranging from .060 to .080. Exhaust ranged from .050 to .085. For the next head I used the same already compressed gasket and just snugged the bolts down. Intake clearances ranged from .075 to .095 and exhaust from .065 to .100. This side was probably larger because I didn't torque the bolts. Even torqed there would have been plenty of clearance.

At least you know that you won't have valve/piston lovin' going on!

Ok I've never rebuilt one of these engines-- what causes the differences in the valve clearances? Could it be your washers taking up slightly less or more space in the lifters or something else?

The_Josh_Bear said:

Ok I've never rebuilt one of these engines-- what causes the differences in the valve clearances? Could it be your washers taking up slightly less or more space in the lifters or something else?

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I don't think it was the washers. I only made two lifteers and the differences were all across the board. I don't have a proper tool to check the valve recession. I may buy one. The best that I could do was with a dial caliper and a straight edge and the biggest difference was about .010, with no way of telling if the dial caliper was measuring perpendicular to the valve.

I feel like pulling the cam to measure the lobes, but I also don't want to scratch the bearings. With the rotating assembly already installed it is harder to guide the cam through ever so gingerly. Since everything fits so far, I want to just leave it. It's just that darn OCD is nagging!

I would torque it down and measure it again, that’s a lot of variance

Edit, which cam?

The_Josh_Bear said:

Could it be your washers taking up slightly less or more space in the lifters or something else?

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When you modify the lifters, there should be no up and down play in them to make any difference. If there is, it defeats the purpose of doing the mod in the first place.

Thewespaul said:

Yep no need to worry about the assembly lube, if you really want to be **** about it you could plastigauge one main cap with no lube then add lube and see how much the tolerance changes, then use the difference to figure out where you want your tolerance to be.

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I was taught from my dad a auto machinist , had his own shop, that you don't check clearance with plastic gauge with oil . Because it will give an incorrect reading. Always did it dry. Also we only assembled engines with assembly lube and never assembly grease . Reason being with the grease if got a speck of dirt in it would not see it like you can with lube.

Don't believe I have seen it , but what year of 6.9 engine did you start out with. First or second series.

Ok where do you find the series years at for the 6.9 . I have seen it here. I have a 83, 84 core and a late model 86 in old blue.

Thewespaul said:

I would torque it down and measure it again, that’s a lot of variance

Edit, which cam?

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I may do that this weekend. But I still had a variance of .020 on the intake and .025 on the exhaust for the head that was torqued down. It is the newer Typ4 cam.

IDIBRONCO said:

When you modify the lifters, there should be no up and down play in them to make any difference. If there is, it defeats the purpose of doing the mod in the first place.

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Right. There was no up/down play. The retainer would barely fit in.

Randy Bush said:

Don't believe I have seen it , but what year of 6.9 engine did you start out with. First or second series.

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I'm not sure what year the motor is, but it is a later version with the bolt-in piston oilers. Comparing the serial numbers to a chart that I found somewhere on this website, it should also be the version that was upgraded in the crack-prone areas. The number is 69D U2 U310391.

Randy Bush said:

I was taught from my dad a auto machinist , had his own shop, that you don't check clearance with plastic gauge with oil . Because it will give an incorrect reading. Always did it dry. Also we only assembled engines with assembly lube and never assembly grease . Reason being with the grease if got a speck of dirt in it would not see it like you can with lube.

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Yes, everything was dry when I checked the clearances. What I was worried about was that the assembly lube seeped into the mating surfaces between the rods and caps during the final bolt up. I was mainly concerned that the lube might work loose over time, causing a loose rod bolt condition. But I really saw no way to torque it without the lube squeezing in there. I imagine that it must happen all the time.