MOS2 for HEUI Powerstroke

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I have a 2002 7.3 powerstroke that I bought 2 years ago. When I first got it it hardly started in the 20s unless it was plugged in. The oil used was Rotella T5 10W-30. The HEUI system requires good oil flow to the injectors to get them to fire. If the injectors hang up a bit till oil is flowing thru them real good--well then you'll be cranking for quite while and draining the batteries. The first winter I upsized the glow plug relay and put REV X in the oil. REV X is supposed to clean injectors and leave a lubricating film on them to aid in the dry starts on HEUIs. The two things together made a huge difference and it started pretty good after that even without being plugged in. The 2nd winter I again used the T5 but put 2 cans of Lubro Moly MOS2 in the oil instead of REV X. Its cheaper and I'm thinking there may be more overall benefits and less risk. I think REV X uses a lot of boron. I'm not big on oil additives but I am big on reliable ignition in cold weather without long cranking or requiring a plug in. The truck is a hunting truck so it needs to start reliably in cold weather without a plug in. At home its always plugged in to save wear on the engine and batteries. But again when out hunting it needs to start in cold weather with no difficulty to be reliable. So last winter I put the moly in the oil and every time I'm out hunting and it has a cold start it fires right off. One night in January they were calling for negative temps so I unplugged it to see if it would start the next morning. It was -4 F next morning -- I cycled the glow plugs twice and turned it over. It fired right away and idled smoothly till warmed enough to drive. Again I'm not a fan of additives, but this MOS2 really seems to help the HEUI on cold starts. Is there any possible downside to running 2 cans of MOS2 in the oil thru the winter? I realize this is not a tested combo, but it really seems to work well in the winter. Thoughts?
 
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JHZR2

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Wow, the oil makes the injectors work? Seems like a convoluted system... I'd start by looking at your sump size and treat rate. I think the mos2 bottle is only good for 5-6qts, and I bet you have more. So just to get 'spec' levels you may need to dope it a bit...
 

T-Stick

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HEUIs systems have been around for a while and are used by Navistar and CAT. I use 2 bottles of MOS2 which is good for 12 quarts of full dose. I have a 15 quart capacity, so another bottle would be too much and you don't want to overdose. This summer I ran 15w-40 Mystik JT8 since it has 50 ppm of moly just try to keep the moly plating potentially preserved. Since the winter moly treatment, the truck's engine and injectors are significantly quieter than when I bought it with much better throttle response. However I can't find information on where anybody else is using it with HDEO.
 
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Lubri-Moly of Germany makes both a MoS2 additive and a motor oil with it as an additive prominently featured on the label. I used the additive for OPE and I like how it made the engine run.
 
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Don't those engines shear oil due to the high oil pressure at the injectors? It would be interesting to see if the oil shears less with mos2 in there.
 
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Originally Posted By: T-Stick
HEUIs systems have been around for a while and are used by Navistar and CAT. I use 2 bottles of MOS2 which is good for 12 quarts of full dose. I have a 15 quart capacity, so another bottle would be too much and you don't want to overdose. This summer I ran 15w-40 Mystik JT8 since it has 50 ppm of moly just try to keep the moly plating potentially preserved. Since the winter moly treatment, the truck's engine and injectors are significantly quieter than when I bought it with much better throttle response. However I can't find information on where anybody else is using it with HDEO.
I have been adding a can of Mos2 to all of my engines. These range from 4.5 qts to 7qts. It says 50ml per QT of oil, which is 1 can treats 6 quarts. I haven't seen any negative effects from adding a whole can into a 4.5qt sump unless someone has some results that over dosing it a little is going to hurt something, I don't see the harm? I know there are VOA of it out on this site, and can't remember exactly what the results were, but if I remember correctly the ratio of 1 can to qts of oil would put the Moly level at around 300 ppm??? Is a little more really going to hurt anything?
 
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Yeah those injection systems are kinda cool. It's basically using the oil as hydraulic fluid. Remember when you change the oil to change the oil that is left in the system as well. There is quitr a bit that doesn't come out of the pan.
 

T-Stick

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That aspect has been discussed quite a bit but the consensus is: If you want to, you can change the oil in the HPOP, but this oil circulates with the sump oil and is mixed with the newly changed oil. Ford does not ask for the HPOP oil to be changed and would take that into account in the service interval. Back to the MOS2--I find the engine and injectors running noticeably smoother with moly either added to the 10w-30 oil or by running a 15w-40 Mystik JT-8 oil in the summer that has some moly in it. I want to run 10w-30 in the winter and don't know of a readily available 10w-30 with good doses of moly therefore I add it. However even with the perceived benefits I'm still a bit skeptical of top treats upsetting the chemical balance and potentially causing other issues. This is why I'm asking if anyone else has used the MOS2 with a 10w-30 HDEO.
 
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Don't worry yourself with changing the HPOP system as its not needed. I do agree with the moly in the add-pack as I also think it helps to keep the system in top working order. The Deere Plus 50 II 10w-30 that I use has a good dose of moly in it. I don't believe in additive supplements either as I believe they can disrupt the add-pack also.
 

T-Stick

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How many ppm of moly is in the Plus 50 II 10x-30 that is CJ-4? I can't find a VOA anywhere. I also checked locally at one Deere dealer for Plus 50 II and they only carry the 15w-40.
 

T-Stick

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I just noticed over 300 ppm on one of your UOAs after 7300 mile so yes, that's plenty of starting moly. I need to look for some Plus 50 10w-30.
 

T-Stick

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Talked to a Shaffer's salesman and asked about adding their moly to other engine oil. He said it should be fine as they generally don't view moly as upsetting the critical chemistry, it just not a tested product when its added, so it can never be guaranteed to be fine.
 
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I hate to throw this wrench in, being a fan of the PSD engine since 1994.5 I'm going to tell you you fixed your hard start issue by replacing a bad glow plug relay. The 7.3L must have a good functioning glowplug system. And if so it will start with aunt jimimas pancake syrup in the oil system. Might be "sticky" but it will start at 0*F.
 

T-Stick

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The glow plug relay was replaced with a significantly larger one--not OEM. I've never known a glow plug relay to quiet injectors or stop cold romps ... course I never knew you could use Aunt Jemima's for that either ... but then again I may not have as much experience in the kitchen ...
 
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Op The moly in mos2 and the organic moly found in engine oil share only the name moly and that's where the similarities end. And they work differently too,so the organic moly in the oils additive package doesn't plate or layer like mos2 does,so keep that in mind. They act differently and your logic is a bit off combining them like you are. Anyway after reading your post I suggest you do some digging to inform yourself of the different types of moly used,because it appears to me that you believe that organic moly and mos2 are the same because they've shared the word moly,when the reality is that they are in no way alike,other than having the word moly as part of the name.
 

T-Stick

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I know that there are different types of moly. I know that I don't know all there is to know about their chemical compositions. I think chemists are still experimenting some with that. I did convolute the different types in some of my posts. However there are some basic shared characteristics of moly types--they reduce wear and they have good lubricating qualities. I noted the MOS2 seems to work well for cold weather starting because of the plating-- essentially making pre-lubricated surfaces. Shaffer's moly treatment also plates so its not just the Liqui Moly MOS2 that does this. I also noted that Moly, whether added in MOS2 or as an engineered oil additive, quiets the injectors and the motor significantly. I know this from using CJ-4s with and without moly. So I'm concluding that moly in oil is a benefit to the HEUI engines for starting and running smoothly. There is a noticeable difference. What I don't know and was asking is if there is any downside to running MOS2 in an HDEO?
 

T-Stick

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Well I think I did the right thing ... I found a local Deere dealer that carries JD plus 50 in 10w-30 and it was only $18.75 per gallon. Based on the 500 hour spec (or changing once a year for time) of this oil--it essentially equates to 25-30k of driving time averaging 50-60 mph. No wonder the UOAs for this oil look so good at 7.5k.
 

T-Stick

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It doesn't run any differently now. The test will be in cold weather starting.
 
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