My Universal M4-30 has a tube-in-shell heat exchanger and I keep 1/8" wooden dowels in my spare kits to rod out the tubes occasionally. IIRC use a 9/16" box wrench to remove the single bolt holding each end cover and push the dowel through to the other side. There is a zinc screwed into one end to protect the engine and I change that each year, and rod out the heat exchanger. It's handy to setup a small wet vac to clean up the water and scale that falls out. The dowels break easily so buy several from the art supply store or WalMart craft department and cut them in half (18") so you can store some aboard for future.
I would rod out the heat exchanger before acid cleaning, to clear all the passages, and maybe blow them out with air, to make it easier for the acid to do it's job and ensure it has equal time to clean all the surfaces. Chuck Scheaffer Resolute 1989 C&C 34R, Pasadena Md > On 01/13/2021 9:37 AM Joel Aronson via CnC-List <cnc-list@cnc-list.com> > wrote: > > > I've heard of using rifle cleaning kits or wood dowels too. > Joel > > On Wed, Jan 13, 2021 at 9:33 AM Della Barba, Joe via CnC-List < > cnc-list@cnc-list.com mailto:cnc-list@cnc-list.com > wrote: > > > > > > If you take the end caps off the heat exchanger, you can see the > > tubes the raw water flows through. Flushing and replacing the coolant does > > not touch the inside of these tubes. To truly clean out the heat exchanger > > you need to remove these caps. I stuck mine in a tub of hot water and > > detergent, which worked OK for mild cleaning. I could seen into the tubes > > and there was nothing but a little slime. More robust measures are needed > > to remove scale and barnacles. > > > > Back in the day it was common to get car radiators boiled out at a > > radiator shop. If any shops are around that still do this that will clean a > > heat exchanger too. > > > > > > > > Joe > > > > Coquina > > > > Thanks to all of the subscribers that contributed to the list to > > help with the costs involved. If you want to show your support to the list > > - use PayPal to send contribution -- https://www.paypal.me/stumurray > > Thanks - Stu > > > > > > > -- > Joel > > Thanks to all of the subscribers that contributed to the list to help > with the costs involved. If you want to show your support to the list - use > PayPal to send contribution -- https://www.paypal.me/stumurray Thanks - Stu >
Thanks to all of the subscribers that contributed to the list to help with the costs involved. If you want to show your support to the list - use PayPal to send contribution -- https://www.paypal.me/stumurray Thanks - Stu
