sorting out my 12v

F

firemn260

New member
Joined
Feb 20, 2015
Messages
53
So I pulled the head and found what I was suspecting. Failed gasket between 3 and 4 cylinder. It was deteriorated from number 3 over to the head bolt hole then on to a water passage So I'm guessing that's why my coolant system was pressurized but no cross contamination between oil and water? I'm thinking the studs wernt either installed or tourqed properly.

Anyway I'm glad I caught it pretty early but I'm thinking the guy who sold it to me already knew what was going on.( truck wasn't running when I bought it so I took a chance)
Other than that the head looks good and so do the cylinders and pistons. Actually they look great for a little over 200 on the engine.

at this point now that I know that machining won't be required I decided I'm just going to install a stock gasket and forgo the o rings for now. Local diesel shop wanted 300 just to o ring wich I though was a bit steep.

only other thing head wise is I'm not sure about the valve springs. I was told they are heavier than stock and when I got the truck running it would rev past 3500. I'm going to check the clearance anyway should I just do new #60 springs while I'm at it? I'm guessing it has a 4k governer springs but then again I don't know to much about these mechanical y injected engines.

I was told the afc is gutted. I was reading that a well tuned afc is better than a gutless afc but then again I'm showing my lack of knowledge about these injection pumps. I have been searching forums trying to learn all I can and I'm leaning towards finding the parts to put back in there.

I'm sorry with all the noob questions s and long read. I'm just trying to find a good direction to proceed with my engine. The motor is sitting on a stand right now so it's not going back in the truck until I am sure I did everything right. Thank you so much for any advice.
 
Get som hamilton springs if you want (not the pac brake springs). Pax brake ones perform very similar to stock springs throughout the lift range. Get parts or another AFC to put on and tune to your truck. And O ringing a cummins head is usually anywhere in the $150 to $250 range in my experience.
 
That's if you bring the machine shop the bare head so they don't have to disassemble and re assemble it
 
Thanks. Is there anyway to tell what kind of springs are in it now? Is there a way to tell the differance between stock and aftermarket springs?
 
There's no way I'd forgo o-ringing the head if I had already gone through the trouble of pulling it off.
 
dieselracer07 said:
There's no way I'd forgo o-ringing the head if I had already gone through the trouble of pulling it off.
Click to expand...

I've been on the fence about it. But I guess I will just do it. I will call around. Would it be something that's pretty standard that any automotive machine shop could do?
 
firemn260 said:
I've been on the fence about it. But I guess I will just do it. I will call around. Would it be something that's pretty standard that any automotive machine shop could do?
Click to expand...


Any good machine shop should be comfortable cutting O ring grooves and installing them. They may want a gasket to measure off of or for you to supply the dimensions for it though if they have never done a cummins head.
 
stubz616 said:
Any good machine shop should be comfortable cutting O ring grooves and installing them. They may want a gasket to measure off of or for you to supply the dimensions for it though if they have never done a cummins head.
Click to expand...

I found a diesel performance shop that is going to do the orings. They seem to be a bit pricey but at least I know the have experience working on diesel heads.
I've been scouring this forum for info on the torque process for my arp studs. Seems like there are a lot of different opinions on how much torque and the way you do it. I've heard 95 lbs all the way to 150lbs. I'm kinda confused.
The studs are stamped with 2000 which from what I've been reading are the same as 425? Unfortunately the studs were on the motor when I bought the truck so I can't be sure they we re torqued properly in the first place.
 
take them to 125 ft lbs, in three steps. start truck let completely warm up, shut off, do a hot torque back to 125, reset lash, drive 1000 mile, retorque and reset valves. drive like it is stolen..
 
Make sure you have the ability to check the protrusion after the shop does it. I had one HD diesel shop up here do a head for me. They had the fly cutter cocked when they cut the grooves, where it was out .008" difference front to back on each cylinder. I ended up sending it to a more reputable shop 1200 km away to fix it all.

ARP 2000 studs (incorrectly called 425's) are spec'd at 125 ft-lbs.
 
95cummins5.9 said:
take them to 125 ft lbs, in three steps. start truck let completely warm up, shut off, do a hot torque back to 125, reset lash, drive 1000 mile, retorque and reset valves. drive like it is stolen..
Click to expand...

thank you I know the subject has been beat to death. This is using the arp lube correct?
 
95cummins5.9 said:
yes, definitely use the arp stuff.
Click to expand...

Thank you so much for the quick replys. Coming from years of experience on powerstrokes I'm learning as I go on these 12valvers and I'm really enjoying working on it so far.

I'm bringing myself up to speed now on adjusting valve lash. Next is learning the injection pump. I'm told the afc is gutted so I'm thinking I'm going to find the parts and start there with tuning.
 
You must log in or register to reply here.
Top