BretWayne Report post Posted November 16, 2012 I recently bought a Diesel Pusher with a 3126 Cat (1999). I see that it has no water filter. Being in the trucking business for over 30 years I'm aware that the 3406 engines of that time had a water filter to dispence a DCA treatment to prevent electrolysis from pitting the liners . I have not been able to get a good answer as to add treatment such as Nalcool or add a water filter. Any advice would be good. Share this post Link to post Share on other sites
wolfe10 Report post Posted November 16, 2012 BretWayne, Welcome to the FMCA Forum. The chassis maker decides whether to fit a coolant filter. The Caterpillar engine in our Foretravel has one, many chassis with the same motor do not. As you know from your OTR trucking background, SCA's can be added as a liquid or by changing the coolant filters (they come with different amounts-- called UNITS of SCA). My first question, if this is a recent purchase is how old is the coolant in there now and as importantly what coolant is it? At 13 years old, it is unlikely to be the original coolant chosen by the chassis maker (we sure hope not). It could be another "low silicate for diesel with added SCA" coolant, or it could be one of the new generation OAT-based coolants. If you don't know for sure, were it mine, I would replace the coolant now so you know what is in there and that it is properly protecting the cooling system. Brett Share this post Link to post Share on other sites
BretWayne Report post Posted November 16, 2012 Thanks Brett, I plan on changing it just to be sure. You confirm what I have read-- that the new coolants with the SCA added would give sufficient protection. Share this post Link to post Share on other sites
wolfe10 Report post Posted November 16, 2012 Actually I am a big fan of the new generation OAT-based coolants. 6 year life, no SCA testing or adding! If you do your own labor it is less expensive than the three year change with standard diesel coolant. If you pay to have it done, it is a LOT less expensive (little more than half the labor over a 6 year period. Share this post Link to post Share on other sites
BretWayne Report post Posted November 19, 2012 Even though I do my own work the 6 yr life sound good. That's what I'll do.Thanks so much for the advice. Share this post Link to post Share on other sites
wolfe10 Report post Posted November 19, 2012 Here is a step by step description of the process. Very low tech, but it does take time (on the Diesel RV Club Technical Forum-- an FMCA Chapter): http://forum.dieselrvclub.org/index.php/topic,6653.0.html Note on Edit: Link Updated 7/14/13. Share this post Link to post Share on other sites