10w40 Amsoil & 66 Mustang 289ci engine analysis

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Bob,

Just recently bought a 66 mustang with the stock 298 ci v8 with 86144 miles. From all indications the pan or heads have never been off. Did my oil change to Amsoil 10w40 and with about 25 miles on the oil pulled a sample for analysis with Analysts, Inc. Their results are as follows in ppm: Iron 29, Chromium 1, Nickle Tin Phosp 1299, Zink 1445, Calcium 3707, Barium S % vol 0.5, Fuel% 2.3. Request your analysis and recommendations as to rebuild. Am i correct in thinking that Lead= overlay of bearing material, Iron=cyl walls, valve guides, piston rings, oil pump & Nickle=bearing material. In your opinion does the ppm levels indicate my immediate attention? Thank you.
 
Just a well kept car, engine runs great. I am concerned with the iron and lead numbers. This i was thinking of pulling the pan for new rod & main bearings, oil pump, new timing chain and gears.
 
What are the units for water? Is that 0.1%, or 0.1/1 = 10%?

Iron and lead are very high for the miles. Those numbers would be borderline OK for 5000 miles on the oil. Has the engine been sitting for a long time? If so, you may want to do a couple short (100 mi) oil-change intervals with a cheaper oil than Amsoil (either a 10W-40 PCMO or 15W-40 HDEO) to clean it out.
 
The water analysis was presented like this: Water % 0.1. The car did a lot of sitting, will try and flush it out as you suggest.
 
Ok, since the water's just 0.1%, it's probably just condensation. If it was 10% I would have been asking about a head gasket leak.
 
Very interesting.

I, too, have a classic old 1966 Mustang 289 v-8, with about 78k miles on it (IIRC). Engine has never been apart. I run 10w-30 Rotella dino in mine. I'll have to pull another UOA here in a year or so and we can compare/contrast.

The wear metals in these old Windsor v-8's can be pretty high. The 289 was known to eat cam bearings, and then wear into the cam itself after the bearing material is done. My oil pressure is fine when running at driving speeds, but it's VERY LOW when idling; my cam bearings are on their way out. It's inevitible. But I look at it as an upcoming opportunity to do a teardown, and add a little spice to the engine someday when time/money offer the opportunity. Modern materials and better machining available today can make these engines last much longer, if a proper reman is done.


Does your engine need "immediate attention"? Probably not. But you might as well start saving up money for the rebuild; you cannot avoid it. You can prolong it a bit, but it's not avoidable.


In this case, using Amsoil isn't worth the money. Your OCIs are going to be short enough that syns won't make any difference. Use either a 10w-30 or 15w-40 HDEO dino. That will do as well for less cash. No oil is going to stop the pressure decay; it will eventually get so bad that you'll have to address it. When you cannot hold decent pressure even at driving rpm, it's time to tear her down.
 
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Good advice on the dino oil. Among other things i've been an Amsoil dealer for 27 years so i have some sitting around. I'll may drive it till i hear bad noises? This past summer one of our guys in the Mustang Club had a low mileage 289 from a Fairlane that i passed up. Then i may put in a crate 302 and be done with it? I've done the T5 conversion already and the 302 will bolt right up. I guess i'll put a few miles more on the oil in the spring and do another sample.

T
 
If that engine has been run with conventional oil its whole life, the Amsoil may have have done some cleaning that bumped the wear metals up. I'd stick with a conventional 15w-40 until you get a chance to investigate further.

How much do you plan on driving this car? If it is only taken out on occasion it may run for many years just the way it is.
 
The wear metals were very obvious when i drained the dino oil. Things are coming apart reference the oil analysis. I may just go ahead pull the pan and change the rod and main bearings before the crank is damaged. New pump and gears at the same time. It does not burn any oil so i may just stop there.
 
Like Rob Roy said, the Amsoil is just cleaning up deposits over the years, I wouldn't panic, I'd just go to a 10W-30 or 15W40 HDEO, and do some short changes.

Don't short-change the engine by planning a rebuild or replacement, if it runs well it will last years. My dad got around 150k miles out of a 1967 289 Mustang as a DD throught the 1970's, and it was driven hard.
 
I am aware that Synthetics loosen up deposits. However in this case there were excessive metals visible in the dino oil I drained before changing over to Sny. I'll run it awhile and change out the filter and drain some out of the sump when its cold before testing again. Thanks everyone.
 
A cheaper option for you, and may actually involve less effort is to find a late model roller 302 (87-95 Mustang, 96-2002 Explorer) and swap your intake, distributor....etc onto it. You could run an electric fuel pump or swap your old timing cover on to retain the mechanical one.

You'll make more power, get the superior HO firing order, and get a roller cam and lifters for your efforts.
 
Originally Posted By: NateDN10
Ok, since the water's just 0.1%, it's probably just condensation. If it was 10% I would have been asking about a head gasket leak.


doubt it, more of an indication he's over fueling. especially with 2.3% @25 miles. This engine is overfueling a lot. Surprised, I know analysts and they usually provide FTIR.
 
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