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Discussion Starter #1
So, I've got a 12v donor from a 94 ram, that im looking to swap into my 78 f-250.

While the engine is out, I'd like to replace every seal and gasket i can get too, except for the head gasket.

The engine has about 285k miles on it.

I found a guy online selling both Cummins oem upper & lower gasket kits, for $285 +tax altogether.

This seems like a good bargain. Seems like vendors are selling each kit by itself for that much or more.

Is there anything else i should get to replace on this engine? I know about the KDP.
 

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With 285k I suggest you pull the head and get a valve job done. If it is the original head gasket it needs to be replaced with the new style anyway.
 

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Discussion Starter #3
With 285k I suggest you pull the head and get a valve job done. If it is the original head gasket it needs to be replaced with the new style anyway.
In my research, I read from more than one person that at this mileage, as long as the engine was running fine (it was running great), and as long as you weren't turning up the wick too much, that it was recommended to just leave the head on, until such time it needed to come off.

Is there a specific risk to using the old style gasket? I don't know if it's ever been replaced, but I would assume not.

I was simply avoiding taking the head off, to save money on the swap. If I take it off, then I'm tempted to put arp studs in, to help "future" proof it lol. At the same time, I didn't figure on having a head gasket either.

I know you know these engines well GAmes, so if you insist it I will likely follow your recommendations.
 

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It's totally up to you. A man I know who was a pioneer in souping up Cummins 12 valves recommends doing a valve job at about 3k. The old head gaskets have a history of leaking near the t-stat housing. Mine started around 195k. An upper kit will come with one, so you might as well use it. That also gives you a chance to check the cylinders and piston tops. If you don't know the history of the engine you could find the PO burned waste motor oil and the engine is full of carbon.
 

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Discussion Starter #5
Very well.

If I'm taking the head off, i want to go ahead and put studs in. Not sure that i "need" them, but I'd hate to have that limitation later on.

Can you recommend a head stud kit, part number, or link? I assume ARP is the recommended brand.
 

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Using milage to determine engine wear is relatively useless.

If the engine smokes after sitting and smells like oil it need stem seals and probably a valve job.

My 97 has over 300,000 miles pushing snow and pulling and large bumper pull travel trailer most of its life and it does not burn oil, nor does the head gasket leak. Am I jumping up and down waiting for a valve job? No.

I would do front and rear main seals, tappet cover, a re-seal on the vacuum pump (if applicable), and oil pan. With the oil pan off you can look inside; cylinder walls, camshaft surfaces, and if you feel motivated you can pop a bearing cap off and see if the engine is hammered. Oil analysis is also a very cost effective health check too.
 

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Using milage to determine engine wear is relatively useless.
Maybe, but to discount mileage is foolish. The engine is out of the truck. It isn't nearly the same chore to pull the head as it is when the engine is installed.
 

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Very well.

If I'm taking the head off, i want to go ahead and put studs in. Not sure that i "need" them, but I'd hate to have that limitation later on.

Can you recommend a head stud kit, part number, or link? I assume ARP is the recommended brand.
I recommend you save that money. If you end up with the modifications down the road that would require them they can be installed one at a time. I estimate that 90% of the members who have them don't need them but instead installed them because saying "I have headstuds" sounds cool. The gasket set will come with a gauge to measure the head bolts from the engine for stretch. More than likely they can be reused.
 

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Discussion Starter #11
I use these. https://www.genosgarage.com/product/cc2525/oil-filters, but I buy them from a supplier who sells in bulk.

Many others use Blackstone labs. I believe they send you the sample bottles and you pay them whenever you send in a sample.
Thanks, I'll check that out.

And you're right, the head will never be easier to remove, so I should do what I can right now while the engine is out.

Another question: since the head is likely coming off, with valve work, should I invest in stronger valve springs? I planned on eventually putting in a 3k or 4k GSK. I know I don't strictly need stronger springs, as long as I'm not redlining it. But at the same time, it would be nice peace-of-mind to not worry about putting my foot in it so irresponsibly.

Is there any issue with running the stronger springs, where it would be recommended to keep factory ones if I didn't need stronger ones, that I'm not aware of?
 

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60 pound springs are relatively inexpensive. I have them on the exhaust because I have an exhaust brake and on the intake because the box had 12 in it.
 

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Discussion Starter #13
I recommend you save that money.... "I have headstuds" sounds cool...
...should I invest in stronger valve springs?...
Believe it or not, I am trying to save money, and only spend it smartly.
But I also hate doing the same job twice if I don't have to.
 

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Head studs have little to no value unless you are going to sink a bunch of money into the build. Replacing 26 year old valve springs makes sense to me, especially if the engine has been sitting awhile.
 

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Using milage to determine engine wear is relatively useless.
Maybe, but to discount mileage is foolish. The engine is out of the truck. It isn't nearly the same chore to pull the head as it is when the engine is installed.
Yeah but an unnecessary head gasket, deck grind and valve job would significantly impact the beer budget...
 

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I agree.

If the head gasket isn't blown, torque each factory bolt to 135 ft-lbs, keep timing below 16, and buy beer with the savings. 120 ft-lbs is what I do for the short bolts, apologies for omitting to add this info in this post.

$100 for twelve +60 white stripe valve springs, the pedestal head bolts come off anyway, set valve lash on a cold engine to 8 thou/18 thou, and call it good.

If you ever find the need to do a valve job, buy a fully loaded head for $400 and that's that. Re use the #60lb springs.
 

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I meant head surface, i definitely said that wrong
 

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If the head gasket isn't blown, torque each factory bolt to 135 ft-lbs, keep timing below 16, and buy beer with the savings.
I disagree. The factory tq specs are different for the long bolts than the shorter bolts. I wouldn't touch them, but if I were inclined to I'd do the 66/89 plus 90 degrees.
 

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I do 135 on the regular bolts & 120 on the short bolts (missed typing the short bolt value in my previous post).

I prefer a straight torque method as an equalizer, as the 66/89 + 90 degree isn't as consistent, given even new bolt variations, used bolts, different stretch, differing hardness, fatigue etc.

I've measured different breakaway torque on 2 pedestal bolts torqued right after each other with the torque + 90 degree method.

I disagree. The factory tq specs are different for the long bolts than the shorter bolts. I wouldn't touch them, but if I were inclined to I'd do the 66/89 plus 90 degrees.
 
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