88 4.0 rebuilt engine, blowing oil through cap

[fiddlermj]

Ok. Ive done everything I can to fix this. I rebuilt the engine, rings, piston heads, rod bearings, main bearings, seals, push rods, lifters, rockers, valve cover mods, oil fill cap mods, oil pump, vaccuum hoses, spark plugs, 

 

i drive this truck 5 miles….. its like weak. So i order from trevor waiting on new injectors. MY biggest problem is the 2-3 qts of oil blowing out the oil fill cap in just a 5 mile ride at roughly 45-50 mi an hour. Ive checked to see where its leaking from several times…. Its all from the cap. The ccv is not stopped up. I pull the hose and its sucking. 🤦🏻‍♀️😖. I had a friend do a compression test… he said everything was fine. Sooooooo, i will say the oil shoots 8ft literally from all the rockers. And I assume because of this its just hitting the hell outta that oil cap. Please help

[89 MJ]

What is your oil pressure when it’s running?

[fiddlermj]

Well, the gauge in it says 35-40….. but i think its higher than that

[89 MJ]

30 minutes ago, fiddlermj said:

Well, the gauge in it says 35-40….. but i think its higher than that

I'd agree that the oil pressure seems on the lower end from a fresh rebuild. Might want to check it with a mechanical gauge. Is it a geyser out off all of the rockers or just a few of them? 

[fiddlermj]

5 hours ago, 89 MJ said:

I'd agree that the oil pressure seems on the lower end from a fresh rebuild. Might want to check it with a mechanical gauge. Is it a geyser out off all of the rockers or just a few of them? 

It geysers out of all of them at 8 ft no joke

 

[fiddlermj]

I also want to say…. I put new cap on… still blowing out. Today. The video is pre oil pump, and the oil shoots higher than that.

[89 MJ]

27 minutes ago, fiddlermj said:

It geysers out of all of them at 8 ft no joke

 

Goodness, that's probably what Old Faithful wants to be when it grows up. At least its all rust proofed. 

 

So somehow, it seems that the lifters are getting way too much oil or possibly that the lifters are diverting all of their oil up through the pushrods. I'm betting the first option though. 

 

Does it sound like it has a lifter tick? 

Being that it did it with the old oil pump too, I think we can safely rule that out from being the cause. 

 

I found this on how the oiling system in the 4.0 works:

Quote

From the FSM:
LUBRICATION SYSTEM
A gear—type positive displacement pump is
mounted at the underside of the block opposite the
No. 4 main bearing. The pump draws oil through the
screen and inlet tube from the sump at the rear of
the oil pan. The oil is driven between the drive and
idler gears and pump body, then forced through the
outlet to the block. An oil gallery in the block channels
the oil to the inlet side of the full flow oil filter.
After passing through the filter element, the oil
passes from the center outlet of the filter through an
oil gallery that channels the oil up to the main gallery
which extends the entire length of the block.
Galleries extend downward from the main oil gallery
to the upper shell of each main bearing. The
crankshaft is drilled internally to pass oil from the
main bearing journals (except number 4 main bearing
journal) to the connecting rod journals. Each connecting
rod bearing cap has a small squirt hole, oil
passes through the squirt hole and is thrown off as
the rod rotates. This oil throwoff lubricates the camshaft
lobes, distributor drive gear, cylinder walls, and
piston pins.
The hydraulic valve tappets receive oil directly
from the main oil gallery. Oil is provided to the camshaft
bearing through galleries. The front camshaft
bearing journal passes oil through the camshaft
sprocket to the timing chain. Oil drains back to the
oil pan under the number one main bearing cap.
The oil supply for the rocker arms and bridged
pivot assemblies is provided by the hydraulic valve
tappets which pass oil through hollow push rods to a
hole in the corresponding rocker arm. Oil from the
rocker arm lubricates the valve train components,
then passes down through the push rod guide holes
in the cylinder head past the valve tappet area, and
returns to the oil pan.

 

This has me thinking that possibly the main oil gallery is either somehow larger than it is supposed to be or that the other oil galleries coming off of the main gallery are partially blocked. No clue how that is possible though. 

 

How did the main and rod bearings look when you changed them?

[fiddlermj]

54 minutes ago, 89 MJ said:

Goodness, that's probably what Old Faithful wants to be when it grows up. At least its all rust proofed. 

 

So somehow, it seems that the lifters are getting way too much oil or possibly that the lifters are diverting all of their oil up through the pushrods. I'm betting the first option though. 

 

Does it sound like it has a lifter tick? 

Being that it did it with the old oil pump too, I think we can safely rule that out from being the cause. 

 

I found this on how the oiling system in the 4.0 works:

 

This has me thinking that possibly the main oil gallery is either somehow larger than it is supposed to be or that the other oil galleries coming off of the main gallery are partially blocked. No clue how that is possible though. 

 

How did the main and rod bearings look when you changed them?

I'm reading this right now give me a minute, but yes. it has the sound of ticking again. The old ones were fine just worn down to the brass look. When i went back in… AGAIN…. (Yes i changed everything twice 😖🙄 long story tracking ticking, which eventually lead me to rebuild cause i found rings on 6 broke) they were fine.

[fiddlermj]

Right, so, i installed all the bearings, i pushed in all sliding around…. This is gonna be dumb….cause I'm pretty sure i know but i second guessing myself these days—-but the holes, journals, line up themselves do they not? I know….. i laid them out in order and put new ones back in just like i pulled them out. One goes top the other bottom. One half has the hole… the other doesnt. 

[89 MJ]

You are correct. I get why you’re second guessing yourself, this is a super strange issue 

[AZJeff]

Oil blowing out of the fill cap would be due to crankcase pressurization.

 

Oil geysers from the pushrods would imply some serious blockage in the oil delivery system to the crankshaft, resulting in most of the oil going to the lifters, who, in turn, pump it up to the rocker gallery.

 

Did you clean out all the cross-drilled holes in the crank that feed from the mains to the rods?
 

Did you also make sure all the feed holes from the main oil galley that feeds the mains was clean?

[fiddlermj]

Yea, best i could anyhow, used air, even engine cleaner when everything was apart then air again. It has to be that tho. Lord mercy. Is there a way to do that without taking the whole thing apart…. Again. 

[fiddlermj]

I may just try another engine flush then. 😖. But alas. I have a ticking again so …. New lifters…. Which will open the block anyhow. 

[89 MJ]

I’d try dumping a can of sea foam in the oil and running it at varying rpms for a bit. Maybe 20 minutes or so. Maybe that’ll help, maybe it won’t, but it’s worth a shot. 
 

 

[fiddlermj]

Is there a pressure relief valve somewhere?!?

[89 MJ]

That would most likely be built into the oil pump

[fiddlermj]

1 hour ago, 89 MJ said:

That would most likely be built into the oil pump

So. I dumped whole can (yea i know) seafoam in…. Ran it for bout 30 minutes. Drained oil…. Metal shavings. Guess there is something to the bearings

[89 MJ]

That’s not good. Better than out on an adventure though. 

[Htchevyii]

Oh man, that's frustrating! Something really abnormal is going on, hope that you can figure it out.

[fiddlermj]

Well. I dropped the oil pan. Plasticgage all the bearings (except number 3)… all were .001” except when i got to #3 …. I noticed fore I did it that the bearing did not fit snug in the cap. There is “give” to the top edges.. do i need to get an oversized set… for this one or…..i will plasticgage in morn…. But just wondering

[AZJeff]

5 hours ago, fiddlermj said:

Well. I dropped the oil pan. Plasticgage all the bearings (except number 3)… all were .001” except when i got to #3 …. I noticed fore I did it that the bearing did not fit snug in the cap. There is “give” to the top edges.. do i need to get an oversized set… for this one or…..i will plasticgage in morn…. But just wondering

Your issues are more than just a bearing that is a bit loose.   (BTW, is that #3 rod, or #3 main bearing you are referencing?). If it’s a rod, it should be making a ton of racket when running if it’s as loose as you describe.  Additionally, a loose bearing can cause journal surface damage that would need to be addressed before slapping an undersized set of bearing shells in a given journal, so some careful inspection of that journal is warranted.

 

In addition, your description of streams of oil coming out of the pushrods/rockers would not be explained by this loose bearing.  In fact, if anything, a loose crank bearing, be it a rod or a main, would cause more oil to leak out around that journal, and thus LESSEN the amount of oil getting to the lifters, and in turn, less oil being pumped up the pushrods.

 

Further, have you done a DETAILED visual inspection of ALL the bearing shells and crank journals to try and find the source of the “metal shavings” you reported in your post on Sunday?

 

BTW, what do the lobes on the camshaft look like?  You need to roll the cam around and study them carefully with a flashlight for sights of pitting, scoring, etc.  They may be a source of metal shavings.

 

 

[fiddlermj]

I had a machinist friend come mic the crank its fine. The shavings were coming from the thrust bearing, after i checked the #3 rod bearings i pulled the mains to check and yea….thats the source of shavings. Sooooo. I'm brake cleaning the hell outta all the journals and shooting air thru em. The cam looks good. No ate up spots or pitting etc. i guess maybe the shavings clogged the journals to cause that geysering?!? 

[AZJeff]

53 minutes ago, fiddlermj said:

I had a machinist friend come mic the crank its fine. The shavings were coming from the thrust bearing, after i checked the #3 rod bearings i pulled the mains to check and yea….thats the source of shavings. Sooooo. I'm brake cleaning the hell outta all the journals and shooting air thru em. The cam looks good. No ate up spots or pitting etc. i guess maybe the shavings clogged the journals to cause that geysering?!? 

Wait a second.   Your answer raises questions.

 

1.  How do you measure the crank main journals in the car?  You need to drop the crank to get the micrometer on the widest part of the journal, and that’s not easy in the car.

2.  Thrust bearings don’t create shavings for no good reason.  Did you check the thrust surfaces on the crank for scoring, etc.?  Did you measure crank end play with the new thrust bearing installed?  Was the thrust bearing damaged during installation?  Did you remove the bearing to examine for damage to it and/or the thrust surfaces on the crank?

 

3.   If you have “shavings” that entered the oil passages, they are all over the engine after it was run, and just cleaning the journals isn’t going to remove all that stuff that is floating around the oil system.  Can you post a photo of these “shavings” (with something for scale) and describe exactly what locations in which you found these shavings.

[fiddlermj]

Yea its a good question on that micing. I wasnt there. Soooo….. I'm not sure. I myself didnt mic it. He just said its fine. But now you got me questioning. Yes it was scored. Ill take a pic of all of them in morning. Yea i found the shavings like fingernail clips in oil when i changed it, which is why i removed the bottom. There is a nick in the crank. Not bad that a polishing can't fix. Ive been brake cleaning and air blowing all day. But the thrust has a copper streak all the way. In morning ill post pics of everything 

[fiddlermj]

Ok i went to shop just now. And took pics. 20-30 mi on these bearings.