Engine/Transmission (1994 - 1998) in-truck engine refresh?

[Forrest Nearing]

the '97 is using a little oil... ok, it's using just shy of a lot...



truck still runs awesome, and I don't feel "unsafe" driving it or anything, it's just got a fair amount of blow by... so I'm just looking ahead at my options...



the engine runs smooth, good oil pressure, etc. I'm assuming it really just needs a set of rings. truck only has 212k on it, but I have no idea what kind of life it lived before I got it... I got it from an 18 yr old kid, so who knows...



around town it isn't so bad, but on a long trip under steady boost and with my extended road draft tube, it puts a nice coat of oil mist on the tailgate, rear bumper, under the truck, etc. enough to leave multiple substantial drips on the concrete after 4-500 miles at highway speeds.



I would LIKE to assume that the cylinder walls still look good, but who knows, it may need a hone job too...



I guess my main question is who has done an in-truck ring/bearing job? how bad is it? the #6 hole looks like it might be tough to get a hone into... is pulling the pan a major PITA? I've heard the transmission and adapter plate have to come out?



I'm just exploring all my options... my favorite right now is to buy a decent core and build it up w/ notched pistons, DD cam, tap the block for a 2nd oil return boss, etc. etc. but I've also got to explore the budget options, ya know?



many thanks in advance,



Forrest

 

[blacksheepdiesel]

My bet is it would be much easier to pull the engine and rebuild/replace rather than try an in-frame. On a big truck it is possible because the engine bay is much larger and it is a farther distance from axle to bottom of engine.



Trent

 

[gitchesum]

I think clearance is gonna be your enemy here. There just aint' enough room under the cowl to pull those pistons. That's not to say it can't be done, but I would go ahead and pull the motor and do a full rebuild.

 

[DSiemens]

I would explore some options first. With your mileage, the block should be fine, but the valve guides and or valve seals might be shot. I recently pulled my head and after 400K the block still showed the factory "hatchmarks". A leakdown test will show whether you need rings or valves.

 

[crabman]

Oil Drips

Just some info on the oil drips/mist on trips coming from the breather tube. If you want to eliminate that problem put a small plastic bottle on the breather tube. Drill holes across the screw top and thread a zip tie through the holes and slide onto tube. Pull tight!!

Try vitamin bottles as they come in different sizes.

Just a idea but alot less work that a rebuild.

crabman

 

[Forrest Nearing]

well, I'm losing ~1qt per thousand miles, so I'd be willing to bet that'd have to be one HUGE pill bottle!!



after I first noticed the oil mist, I extended the road draft tube down to where it's only a few inches off the ground... I've been wondering if maybe it's actually DRAWING more oil with it being down in the airstream down there, but there's no breather, so I guess that doesn't really hold air.



I'm surprised that it runs as well as it does and uses as much oil as it does, but I've read somewhere that Cummins spec for "acceptable" oil usage is something rediculous like 1qt/500 miles! try that with a gasser... gotta love a diesel!!



I really can't afford the down time involved with pulling/refreshing/reinstalling, so I'll probably just buy a spare engine and build it up on the side... only problem with that is I've got a feeling that once it's built, it'll probably find its way into a Ford crew cab.



Forrest

 

[cartman]

hi forrest are you sure that all that oil is comeing out of the breather tube, because there were a few engines that the camshaft oil plug on the back of the block they would leak and some would fall out leaving that oil mist under your truck, good luck write back

 

[Forrest Nearing]

well, I will definately check it out, but when I dive under the truck with the engine running, I can see a nice stream of oil vapor coming out of the blowby tube, and just visually "connecting the dots" it sure looks like all of the oil under there is eminating from the tube...



where exactly is the camshaft oil plug? is it just a traditional allen headed pipe plug?



thanks,



Forrest

 

[thaile]

You might not actually need a full rebuild of the truck. It could be that You have a messed up head that is either cracked or is just plain wore out and if that is the case like with a cracked head all of the compression that would be leaking out is going right into the crankcase and is probably pushing the oil out of blowby tube with the buildup of all the compression in the crankcase. When you first start the truck does it have a lot of blowby.

 

[Forrest Nearing]

the only way I can really check blowby is by laying under there and seeing what's coming out of the tube... not much comes out of there, but the oil isn't up to temp either...



it's not pulsing like it's one cylinder, it's a steady stream like it's all cylinders...



Forrest

 

[cartman]

hi forrest the plug is a thick welsh plug you put locktie on it put the plug in place and use a drift and hammer to pound it in place when it bottoms out you wack it once more to push the center in.

on the truck i put the plug in when the first plug bottomed out there was room for more so i pounded a second plug in the hole then filled the rest of the hole with mopar silcone you know that black stinky stuff but it works real good. that was at least 6or7 years ago and no more leaks

 

[Coalsmoke]

What is the expected price?

 

[Forrest Nearing]

looks like a refresh kit is in the $500-600 range (rings/bearings/seals/gaskets/etc. )



I can get a good rebuildable core longblock that just needs rings/bearings for ~$1000-1200... still deciding if I want to mess w/ the downtime or if I want to build something up on the side... I'll probably just do the latter as I can take my time, and like I said, this thing still runs awesome...



Forrest

 

[krs]

Hi Forrest,

Can you compare your dipstick to another one to eliminate the chance that you're overfilling?



Is there any sign of milkiness , white goo, in your oil that could indicate a head gasket leak or a cracked cylinder wall?



Is there any puffing from the oil fill hole with the cap removed, engine running? That would be a pretty sure tell for blowby I'd think.



I've never done a Cummins but I've done a few Navistar 6. 9 (same as Ford 6. 9/7. 3) and the most frequent failure was cracks. Cracks in the head most anyplace, and cracks in the cylinder walls internally or in the water jacket right side externally.



There have been a few messy Cummins show up in here with coolant or oil loss problems that were related to running hot exhaust temperatures. #6, or back three, piston meltdowns, either thru and thru or partial seemed to be more frequent than others. This just from threads here to the best of my miserable and failing geriatric memory.



Spend the time needed to diagnose this, even tear it down, before you spend bucks on engine parts. You might not have a rebuildable block.

 

[Forrest Nearing]

no head gasket problems... there's always going to be oil vapor visible in a hot engine (oil filler) but there's no puffing to indicate that the problem is located at one (or two, etc. ) cylinders



like I said, the truck runs great. I have confidence that it's rebuildable.



Forrest

 

[DMC]

Pressure test the radiator. You may be surprised at what you find. Run it up to about 16-18 Psi.



I recently replaced my radiator. I was constantly worrying about the blow buy. Even had Cummins check it, they said it was in spec. Since the radiator install I haven't seen near the blowby that I previously had.



Might be worth a look.



Good luck



DON

 

[Forrest Nearing]

wow, I have no idea what the radiator would have to do with the oil condensation under my truck...