F250/Cummins Swap

biggy238

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Aug 3, 2008
Messages
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I bought a 3976999 locking dipstick and the corresponding tube.
The issue now is that I'm not entirely sure how it is intended to fit in the block casting it was made for, and it won't fit the dodge 6.7 that I have now. I'm completely fine with machining this block to accept this dipstick tube, but I need to be sure how it was intended to seal before I do that. The small end it 0.375", and the minor bore in the block is also 0.375", but that leaves me with that step and the collar on the dipstick to accommodate.

I don't think it calls for an oring in the parts breakdown, but I don't know that for certain.

If any of you guys can tell me what's up I would appreciate it.

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If they are the same size as you mentioned I would suggest freezing the end of the dipstick mount and heating the block then slipping the dipstick into the block and they will be pretty much joined for life...

You can use dry ice in a stainless steel bowl packed around the end, then heat the block with a torch around the dipstick hole and it should drop right in place...

This is how we did my axle tubes when we rebuilt the housing to lengthen the tubes. We packed the dry ice in the end of the tubes to freeze them and heated the cast housing with a torch. They were machined to have a 0.010 interference fit so they would not at all fir together at room temp. But after the heating and cooling they literally dropped into place it was pretty cool to watch!!!
 
If you want to be able to remove it later buy a reamer .001 larger than the dipstick tube and use loctite sleeve retainer to secure it. That stuff is pretty magical.
 
You guys pretty much hit on the two means all of us in the shop arrived at. Interference fit or ream and sealant. I don't forsee a need to remove it. I have an induction heater and liquid nitrogen. I would **** a brick if that poly line became brittle and snapped though.

I should have snapped a picture of the recess in the block. That collar on the tube won't fit down into it far enough to flush. I will get a picture tomorrow.

All of my freeze plugs have retaining compound on them.

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If it leaks, I will be thoroughly surprised.

I drilled the bore to 3/8" to accommodate the step, oring for added protection, and loctite 620, in addition to the interference fit.
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Part numbers 397-6999 and 397-7000. My dipstick had to come from offshore due to lack of availability.

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I had a kink in my coolant bypass line when I received it (used), so I decided I would do this.
Vibrant performance fittings I picked up from the gents at Kingspeed
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That CAT o-ring will make that Cummins leak......

And, I'm sure you'll make sure the dipstick measures the level correctly for your application and not just take it for granted it's right.
 
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That CAT o-ring will make that Cummins leak......

And, I'm sure you'll make sure the dipstick measures the level correctly for your application and not just take it for granted it's right.



Phhhsss other way around maybe! Cummins is the devil!


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That CAT o-ring will make that Cummins leak......

And, I'm sure you'll make sure the dipstick measures the level correctly for your application and not just take it for granted it's right.
It's description stated ISB 12qt capacity. It will be checked for accuracy.

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Dang. I didn't even think to do my coolant bypass like that. Much nicer than the hose bending around the back edge of the head.

Thanks for sharing.
 
Dang. I didn't even think to do my coolant bypass like that. Much nicer than the hose bending around the back edge of the head.

Thanks for sharing.
I hope it and the dipstick are useful for others.

I need the square cut oring from the water neck adapter. Not sure whether to get it locally or just order it from fleece.

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If you are talking about the bypass kit, it's in the cover on the rear block.

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Ha, I know where trash panda comes from, I like long bed trucks. Cool, when you gonna start a build thread?
I missed this. I lost the drive I had photos backed up to. I have a few more things to work out with converting from vac to hydroboost, clock angle on the transfer case, along with swapping to a dodge Tcase input. The wiring will be a big to-do. I grenaded a 6.7 harness and have to converting it for the 5.9 ECM.



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