Experience and CAUTION with old DEF in the tank

[brobox]

In a conversation with a member last night the subject came up about those that did not travel last year because of the pandemic.
On my 19 my DEF head failing was user error. The unit sat for year in storage before taking it to NIRVC to exchange for the 21. Before leaving, I changed the DEF, it was too late, the ammonia smelling DEF had already ruined the DEF sensor and it quit after changing the fluid.

We are seeing posts of coaches leaving on summer trips that are getting the DEF codes before leaving and are having to cancel travel plans. It is starting to sound like those that did not travel last year due the pandemic, might be having the same problem I did, the DEF turned bad while in storage. It might be worth it for others that are in that situation to purchase a refractormenter and check the DEF before attempting to depart. It won't guarantee the DEF head will continue to work, but may prolong the agony. https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[RonandDeb]

This brings up a great point. Should you periodically change your DEF like you do other fluids?

I agree that older DEF could certainly cause issues and it's mentioned a lot.

I haven't heard many people talking about changing their DEF. As for me, I have a small diesel puller and plan to change it every season whether it needs it or not.

[brobox]

DEF in the tank is very easy to check with a refractometer. I have a piece of 1/4 in tubing, put it in the DEF tank, held my thumb over it and removed and with more than enough fluid in the tube to check the quality. Much easier and cheaper than to randomly change the DEF fluid. Also the refractometer can check coolant concentration and Aqua Hot fluid as well.
After my experience, just kind of a heads of for those that stayed home last year and the DEF fluid may have aged out.

[RandyRich]

Originally Posted by brobox

DEF in the tank is very easy to check with a refractometer. I have a piece of 1/4 in tubing, put it in the DEF tank, held my thumb over it and removed and with more than enough fluid in the tube to check the quality. Much easier and cheaper than to randomly change the DEF fluid. Also the refractometer can check coolant concentration and Aqua Hot fluid as well.
After my experience, just kind of a heads of for those that stayed home last year and the DEF fluid may have aged out.

Has anyone tried this? comes with the hose to reach into the tank to check it. I also purchased the DEF Refractometer and will use both (I am paranoid, what can I say). BTW you guys are awesome, I learn so much from you all.

[fqberful]

Originally Posted by Cr8havoc

Has anyone tried this? comes with the hose to reach into the tank to check it. I also purchased the DEF Refractometer and will use both (I am paranoid, what can I say). BTW you guys are awesome, I learn so much from you all.

IMNSHO use a refractometer, you'll get more accurate ans consistent results.


Costs a few bucks more but will last literally forever. I use one that is for DEF only, I don't like the multi-fluid ones.

[Butte64]

Originally Posted by Cr8havoc

Has anyone tried this? comes with the hose to reach into the tank to check it. I also purchased the DEF Refractometer and will use both (I am paranoid, what can I say). BTW you guys are awesome, I learn so much from you all.

I have one but am a little dubious. I don’t know what/how it is checking. Also i think the tubing needs to be rinsed with distilled water to prevent dried DEF causing erroneous reading.

[brobox]

Originally Posted by Butte64

I have one but am a little dubious. I don’t know what/how it is checking. Also i think the tubing needs to be rinsed with distilled water to prevent dried DEF causing erroneous reading.

I do use the same bottle of distilled water to clean the tube and the refractometer when finished. Good point.

[RonandDeb]

Originally Posted by brobox

DEF in the tank is very easy to check with a refractometer. I have a piece of 1/4 in tubing, put it in the DEF tank, held my thumb over it and removed and with more than enough fluid in the tube to check the quality. Much easier and cheaper than to randomly change the DEF fluid. Also the refractometer can check coolant concentration and Aqua Hot fluid as well.
After my experience, just kind of a heads of for those that stayed home last year and the DEF fluid may have aged out.

It's a six figure coach. Why be cheap when it comes to changing fluids. You can use the turkey baster to check the DEF but it's so easy to get a false positive reading, so be careful.

With my little motor, it makes the most sense to change it altogether..so I'll stick to that method

[hdgoldie]

Originally Posted by Cr8havoc

Has anyone tried this? comes with the hose to reach into the tank to check it. I also purchased the DEF Refractometer and will use both (I am paranoid, what can I say). BTW you guys are awesome, I learn so much from you all.

We have both and Rick uses both. DEF in tank gets checked before trips and every bottle before it’s added. He’s a little paranoid too. OCD can be a good thing. [emoji6] We’re on our second DEF unit, hoping we won’t need a third.

[TXBart]

Originally Posted by brobox

In a conversation with a member last night the subject came up about those that did not travel last year because of the pandemic.
On my 19 my DEF head failing was user error. The unit sat for year in storage before taking it to NIRVC to exchange for the 21. Before leaving, I changed the DEF, it was too late, the ammonia smelling DEF had already ruined the DEF sensor and it quit after changing the fluid.

We are seeing posts of coaches leaving on summer trips that are getting the DEF codes before leaving and are having to cancel travel plans. It is starting to sound like those that did not travel last year due the pandemic, might be having the same problem I did, the DEF turned bad while in storage. It might be worth it for others that are in that situation to purchase a refractormenter and check the DEF before attempting to depart. It won't guarantee the DEF head will continue to work, but may prolong the agony.

My ‘14 Anthem sat for a year 2 different times before we sold it after 39,000 miles and 4 1/2 years. I used Walmart DEF most of the time. We never checked it and didn’t have an issue while we owned it. 2+ years after we sold it the new owner was still merrily running down the road with it.

Our ‘18 Cornerstone was moved twice in 441 days, once 126 miles round trip to NIRVC and another 15 miles to get it inspected for registration. Before we went on our first trip this year I checked the DEF for aroma and with a refractometer, both were good. We took a 500 mile, 3 day warm-up trip then went on a month long, 3,600+ mile trip. I used 6-8 jugs of Walmart DEF on the trip, checked every one with my refractometer before I poured it in the tank. My DEF head failed the first time I started the engine after we returned home. I checked the DEF in the tank with my refractometer and it still checked as good.

I have many years’ experience with high horsepower race and aviation engines. I have never heard of an engine being as “finicky” as they are trying to say our coach engines are with regards to DEF and I have refueled aircraft from some very sketchy tanks and drag cars and bikes from cans that have sat in the garage for a long time. I think it’s obvious Shaw designed a flawed system, whether it was mandated by the government or not. It’s not the government’s fault nor is it the owners’ responsibility.

[brobox]

Originally Posted by RonandDeb

It's a six figure coach. Why be cheap when it comes to changing fluids. You can use the turkey baster to check the DEF but it's so easy to get a false positive reading, so be careful.

With my little motor, it makes the most sense to change it altogether..so I'll stick to that method

Whatever people are comfortable with. Main thing is if people did not travel last season, check/change the DEF before leaving on a trip with what may be expired DEF. I learned that one the hard way and passing it on.
It looks like, from a few posts that have been made, a few have learned it as well. There have been posts of DEF heads going out "while getting ready for our trip" or "just started out". Good chance the DEF may have aged out.

[RonandDeb]

Originally Posted by brobox

Whatever people are comfortable with. Main thing is if people did not travel last season, check/change the DEF before leaving on a trip with what may be expired DEF. I learned that one the hard way and passing it on.
It looks like, from a few posts that have been made, a few have learned it as well. There have been posts of DEF heads going out "while getting ready for our trip" or "just started out". Good chance the DEF may have aged out.

Well said. It just stinks that something like this could strand you without warning.

I guess you could replace the whole motor every year and it still wouldn't be enough..