1984 F250 6.9 IDI diesel

Status
Not open for further replies.
Joined
Oct 4, 2009
Messages
770
Location
Litchfield, Ohio
Here is the most recent uoa of my F250. Kinda disappointing. I changed my water pump during the previous run. The water pump is bolted to the front of the timing cover on this engine. While I had it apart I noticed the gaskets between the timing cover and block where questionable. I expected some coolant in the previous UOA because its impossible to change the water pump and not a get a little in the oil. Looks like I'm going to be tearing back into it
frown.gif
Oil pressure is good and I have no major coolant loss.

oilreport12.jpg
 
37 ppm of sodium (IF it is in fact coolant) is a VERY small amount of coolant over a run this length. I wouldn't jump to any conclusions based on this one report. I would change the oil and do another run of similar length and retest. Take the two reports under consideration then and decide on a course of action. None of the wear metals are high enough yet to be a cause for panic.
 
Concur with sodium, but thats 37 PPM with 5 qts of make up. I think that the numbers are really better than they seem because of the additional make up
 
Why all the makeup oil? That's ~1 qt/1200mi. At that rate of consumption, if it wasn't for the Na/Pb issues, you could virtually not even change your oil.

Charlie
 
I'm trying to remember here.... oil consumption on the 6.9's can be caused by a plugged breather. I remember cleaning mine. It was a valve or something for a crankcase breather that becomes plugged causing the oil consumption.
 
First let me qualify my statements by saying that I have an '86 F-250 with a 6.9L. Have owned it since '87 and it's had a Banks kit on it since '87. I was also a Ford tech trained in the era when our trucks were built. I also have a bypass system on my truck. It was a Racor LFS 801, 7u absolute, but now it's a Racor ABS, currently with a 10u element in it as it breaks in from an overhaul (mostly head work but I went thru everything... less than 0.001" taper in cyls. at 140K miles and perfect lower end). I will work it down to a 5u filter (Racor offers the ABS in 3, 5 and 10u). Anyway, on to your stuff.

Yeah, where is the oil going? A quart every 2500-3000 miles (especially in freeway driving) is more or less normal for a 6.9L. That's what mine did even as a new engine. A quart every 1200.... not so good, especially considering only 65K miles (and I thought my 140K truck was low miles!!!)

First question, how long have you owned this truck? I ask because there is a notorious issue with 6.9L engines and oil consumption. Forgive me for redundancy if you already know this but it may help another down the road. Between the "Add" and "Full" marks is two quarts. If you keep adding oil to bring it up from the midway point to "Full" it will appear to use a lot of oil. If you add one quart when it reaches "Add" it will use substantially less. There is no windage tray on this engine, so I can only assume that the cause of increased consumption with the splashing that goes on.

One of the bad points of having a bypass system on is that it masks things in a UOA. I don't know what the efficiency ratings are for the NTZ filters, but if it's a fine filter, it's going to be altering the UOA readings somewhat. You need to relearn what's "normal." As was said above, between the oil consumption and the bypass filtration, the reality of your situation may be somewhat worse than it looks.

The sodium is alarming but not overly so considering you have no coolant loss. I would press on and test again. If you didn't change the oil, maybe do so as a "cleanout" and start fresh. That eliminates anything from your water pump work.

Finally, don't expect a big drop in wear metals in a normal UOA just because you have a bypass installed. The spectrographic analysis ignores particle above about 5u. The one UOA I got after I had the bypass on but before I overhauled the engine showed only slightly lower metals. I did, however, do a before and after contaminant analysis on the oil and there was a remarkable drop in that area in only 569 miles (see below). This was the LFS not the more efficient ABS.

LFS-802
Before oil had 1,700 miles on it.
Elapsed miles from install to oil test- 569

ISO Codes:
Before- 18/15
After- 16/13



Here's mine before the overhaul:

F250HD2.jpg

Ford2MR.jpg
 
Ive had the truck since June 2008. I only add a quart when it hits the add mark. This does help greatly with consumption.

The truck does get run pretty hard every so often. By that I mean started and run hard for about 5 minutes or so. I'm a volunteer firefighter. This is when I notice the most oil use.

A lot of the guys that own trucks with these engines swear that they have noticed lower oil consumption when switching brands from rotella. Ive seen too many guys mention that their truck drinks rotella compared to the other brands. As much as I like rotella I'm going to try something different next oci. Currently running T6 5W40 and it seems to be going even faster.

I added the bypass filter to try and keep the oil cleaner longer. It was a cheap investment. The filter apparently filters down to less than one micron. No real efficiency rating on the thing.

I didn't change the bypass element after the water pump work witch makes me think it may still have some coolant in it. But I would still figure the sodium would drop after adding 10 fresh quarts of oil plus the 5 makeup. I dunno
21.gif
Its getting changed next oil change.

I'm wanting to change the timing cover gaskets in the next week or two and see if that cures the sodium issue. I have about 2000 miles left before I reach the 5000 they recommend. Of course doing this would probably raise the sodium levels even higher but at least I would only have to wait one more oci to see if things improve.
 
I haven't tried every oil in mine. I originally ran a Pennzoil 10W30 SF/CC back in the '80s. By the early '90s, I had upgraded to 10W30 Rotella. That got hard to find in the mid-90s where I was living, so I went to 15W40 Rotella or Delo 400 15W40. I never noted any difference in oil consumption between them, except from the Pennzoil (it used a little more). I now am back to 10W30 Rotella and will switch to the T5 after the break-in. I do think the truck uses less on the more modern oil formulations and looking back at the older specs, you can see why.

Here's a tip. In the mid '90s, I noted an uptick in oil consumption. At the same time, I noted an external coolant leak from one head gasket. Apparently, that was common in my era but most of them happened when the truck was under warranty (lucky me, huh?) and they had a better head gasket (it was external leakage only). I pulled the heads to do the gaskets and noted the valve stem seals were pretty sorry. Replaced them while the heads were off and my consumption went back to normal.

Anyway, try some different oil but if it doesn't change, it's likely the stem seals. I doubt the filter is holding any coolant. Does NTZ use anything like the new Racor ABS elements, that can absorb water.

TIP: when you do the front cover, plan on doing the pan. IMO, you get a better seal at the cover/seal interface points if you mate the pan up to a solidly mounted cover rather than trying the goober on a bunch of RTV and jam the cover down on the pan. Look carefully at the damper seal surface... they are often grooved. A Speedi-Sleeve is available and they work well. When I think about it, dropping the pan (easier on your 4x2 than on my 4x4), you could take a peek at the lower end. Maybe drop a cap or two on the mains and rods and look for the source of your lead issues.

Keep us (me at least 'cause I have a vested interest ( : <) posted.
 
Originally Posted By: Blaze
I'm trying to remember here.... oil consumption on the 6.9's can be caused by a plugged breather. I remember cleaning mine. It was a valve or something for a crankcase breather that becomes plugged causing the oil consumption.
It's called a CDR valve, sits on top of one of the valve covers, can be cleaned with gas or another solvent and shake to break the crud loose. To the OP-keep an eye on your rear main seal as well-I have intermittent trouble with my '89 7.3 when I let it idle a lot-but it doesn't leak going down the road. A stuck CDR valve can also increase oil leaks due to pressure building up in the crankcase (acts like a PCV valve).
 
Originally Posted By: bullwinkle
Originally Posted By: Blaze
I'm trying to remember here.... oil consumption on the 6.9's can be caused by a plugged breather. I remember cleaning mine. It was a valve or something for a crankcase breather that becomes plugged causing the oil consumption.
It's called a CDR valve, sits on top of one of the valve covers, can be cleaned with gas or another solvent and shake to break the crud loose. To the OP-keep an eye on your rear main seal as well-I have intermittent trouble with my '89 7.3 when I let it idle a lot-but it doesn't leak going down the road. A stuck CDR valve can also increase oil leaks due to pressure building up in the crankcase (acts like a PCV valve).
Thats it! thanks! just could not remember it.
 
An interesting observation (to this oil geek anyway).

I have Racor ABS bypass system on both my trucks, the '05 F-150 gas and the '86 F-250 diesel. I was reading in the Racor literature that you can pull the caps off the canisters to look at the media as a diagnostic because it will stop everything there at about 45u... so it's visible. You can also read if you have been running significant amounts of water through. So I pulled the covers of both.

I have about 200 miles on the Ford diesel after the overhaul and expected to see a lot of junk. Not so... just a very few very small flakes visible (supposedly the human eye can see objects 40u and above). I looked with a magnifier and saw a few more. Conversely, I saw lots of junk on the F-150 filter. Granted, it's run 1,000 miles longer but....

Oh wait, I just though of the difference. The bypass on the F-150 is plumbed to divert oil before it goes to the primary filter. On the F-250, it's plumbed to receive oil after it's been filtered by the primary filter so, of course, most of the big junk will be caught there.
 
Thanks but when you get close, the old boy is showing his age a little more than I would like... and that's OK by me because so am I! ( : < )

Here are both the LFS and the ABS on the truck:

RacorLR.jpg

This is the original LFS system as installed. The arrow indicate the location of the filter and return.

Rac1LR.jpg

The new ABS canister, filter and bracket. This is a pre-production unit I was testing. The current ones have "Racor" cast into the body and no decal. No, it's not TP, though I imagine the TP filter was it's inspiration. The oil flows through 114 millimeters of a cellulose material with progressive density. Flow is up thru the center than down thru the media and out the bottom. The larger particles are trapped in the upper portions, where they can be observed as a diagnostic tool. Smaller particles are trapped deeper in the media where its more tightly packed. A major side benefit is the ability to trap up to 200 ml (6.7 fluid ounces) of water, as well as resins and “soft” oxidation residue before it turns into sludge or varnish. I think the filter shown is the 5u absolute. These are also preproduction filters so they are not marked the same way as the production ones.

Rac2LR.jpg

The ABS canister was almost a direct replacement for the LFS, so I mounted it in the same place and even used the same hoses. One majot difference is that the LFS, mounted upright, does not drain down, while the ABS, when upright, and with a bottom outlet, will drain back into the crankcase.

Rac3LR.jpg

The New ABS and older LFS side by side. The ABS is a lot more convenient to change due to the top lid. With the LFS, the bottom can unscrews and you need room below to drop the can. The LFS uses a string wound element of 8u nominal (about 10u absolute). Both these filters can be mounted in any position, though upright is the least messy when it comes to service.
 
Here is the latest. Still wondering if I have a coolant leak some place
confused.gif
I replaced the timing cover an water pump gasket on the previous oci. Didn't sample as I figured it would be a waste. Kinda figured sodium would be lower this time around as a result.

late2012oilreport.jpg
 
It's definitely coolant. Question is this: is intusion still ongoing or is this residual going to subside? Only the next UOA or two will tell for sure.

Good thing, as they noted, is that the wear metals are trending down, so no panic or other action needed. I'd stick to 5k miles for the next OCI for the sake of consistiency. If coolant improves, then extend. If coolant does not improve, seek the source or live with the potential consequences.
 
Last edited:
My 87 F250 only has 68K on it and it too is an oil burning fiend! I don't even keep track of it any more. just dump in a qt when it's down to the "add" mark.

I'm guessing valve stem seals. IMO It runs and starts too good to be sick. Well it runs as good as a non-turbo diesel will.

I have been playing with the timing some and that really woke it up. When I got it I would struggle to merge onto the fwy. Now I can merge @ the speed limit! No more downshifting on the smallest hills either, now I just power over them in 4th gear.
 
Originally Posted By: CDX825
Here is the most recent uoa of my F250. Kinda disappointing. I changed my water pump during the previous run. The water pump is bolted to the front of the timing cover on this engine. While I had it apart I noticed the gaskets between the timing cover and block where questionable. I expected some coolant in the previous UOA because its impossible to change the water pump and not a get a little in the oil. Looks like I'm going to be tearing back into it
frown.gif
Oil pressure is good and I have no major coolant loss.

oilreport12.jpg



Interesting UOA and good luck finding what might be a coolant leak, BUT why have Blackstones put a ? in the anti freeze line?? Also do you know what is in your coolant, because although a coolant to oil leak shows as increased Sodium it often shows as an increase in Potassium and that figure is still low.
Might be worth checking the head bolts are torqued correctly and because of the jump in PB from the main bearings, which could be just a particle streak, I would just do short OCI's but leave the oil filter in place for the full recommended interval and use a cheap oil until you have resolved the issue.
If you can't find the source, try a can of Liqui Moly stop leak in the oil and another for the coolant as you might get lucky because the coolant leak is very small at present.
The other figures seem good, so once the Pb and Na figures trend downwards I would guess this oil could be capable of 10K mile OCI's as the TBN was high, although the change in SUS figure would be a factor. Not an issue if this engine is also OK for a 30 grade. I like to start with an oil with a higher viscosity than required for long OCI's so that the oil is still good when it thins out.

PS. Some sealants can cause a spike in Sodium so I suppose there is a chance that if the coolant does not contain Potassium additives this is some excess sealant caught in the oil pick up strainer. Hard to tell with the question marks in the AF line.
I would vote in favour of a particle streal from the main bearings as the Iron would have jumped more if this was a more general wear problem, so the next UOA will be interesting in trend terms. If you take the cautious approach then doing a 3K mile OCI will allow a comparison with the previous 3K figure.
 
Last edited:
Status
Not open for further replies.
Back
Top