Good Guys at SENDURE & Heat Exchanger Source & Flix

[Stu Jackson]

I was searching for a new 3 inch heat exchanger (HX) for our M25.  I had upgraded from the OEM 2 inch HX many years ago.  We had a persistent fresh water coolant leak - I use the more expensive non-toxic stuff, about $20!!!  Recently the HX bracket broke and we found evidence of continued leakage of coolant.  We found a new bracket at our local Universal distributor.  We replaced all the 7/8" fresh water coolant hoses on the engine (I'd replaced the hoses to the hot water heater a few years ago).   Turns out the broken bracket had let the HX rub against sharp edge of the broken bracket that was still bolted to the engine, and the HX had developed a small hole in the shell of the HX right where it rests on the new bracket - we could see the the coolant leak but the shell was resting on the rubber bicycle tubes I'd installed between the shell and the HX.

In searching for a new HX, I realized Sen-Dure made them and got in touch by phone with them.  If you know the Universal part #, Sen-Dure has a great cross reference system.  Ron was a pleasure and a great help.  I looked in the Universal manual, right here in our C34 Tech wiki section, and the Torreson website (www.marinedieseldirect.com) & (http://www.marinedieseldirect.com/catalogs/catalog_group.php?owner=mdd&page_ident=200142-49&model=M-25%20/%20M-25XP%20/%20M-25XPA&manufacturer=Universal&title=Heat%20Exchanger%20Group%20-%20New&quant_position=&catalog=200142&printparts=&printservice=&printoperators=&comment1=Part%20number%20299835%20is%20for%20the%20M-25XP.), and learned that there are TWO different 3 inch HXs.

Universal Part #302631 is the HX with two separated brackets welded to the shell.  It is used on M25XP engines.  The brackets are bolted to the back of the engine.  This is part #11B on the Torreson parts page.

Universal Part #299835 is the HX without the bracket.  It is used on M25 engines and those M25XPs that may, just may, have the HX that is held on by TWO HUGE HOSE CLAMPS.  There is a separate bracket that bolts on to the engine, is shaped like a saddle, and has a slot for the hose clamps to grip and then grasp the HX [this is Torresson Part #12].  The HX is part #11A on the Torreson parts page.  [Torreson Part #11, #299049 is the OEM 2 inch HX that came with the M25 engines.  Many of us have upgraded to the 3 inch HX for our M25 engines.]

Ron sent me the detailed drawings of both models, and I determined I needed the #299835.

The Universal prices are $860 and $761.  Yikes!!!  Sen-Dure is $456 + s/h & tax.  WOW!

If you need a HX, or other engine related parts, check their catalog on line.  Better yet, call 'em.

Please know that Ron is one of the Really Good Guys.


Ron Schaper
Sales Manager
Sen-Dure Products, Inc.
6785 NW 17th Ave.
Fort Lauderdale, Florida 33309
Phone 954/973-1260
Fax 954/968-7213
R.Schaper@att.net
www.sen-dure.com

[Ron Hill]

Guys : In case you might be interested there's toll free Tel # (800)282-0123.  Glen Mar Marine,    Ron

[DaveM]

For information found this alternative to the Sendure for the mid $300 made by Seakamp.  Quality looks good.  Will know about performance when I splash in early summer.

http://www.go2marine.com/product/97977F/universal-medalist-direct-replacement-heat-exchangers-oil-coolers.html

Good Winds
DaveM

[Mike and Joanne Stimmler]

Stu,Could you have had it repaired by a radiator shop?

Mike

[Ralph Masters]

Grreat information, thanks.  Have the replacing of the HX on my "to do" list.

Ralph

Ciao Bella

[Stu Jackson]

Stu,Could you have had it repaired by a radiator shop?

Might see if that'll work and save it for a backup, you know, for "next time!" 

[Ken Juul]

IIRC the heat exhanger body is brass.  Just about any welding shop should beable to patch the hole for you.

[Mike and Joanne Stimmler]

The radiator shop should also be able to pressure test it for you as well, both fresh and sea water sides.

[Stu Jackson]

New one in today.  Pictures to follow.  Agree with "fix the old one" and will do, thanks.

It all started out with a broken HX engine connection bracket.  Our M25 came with the bracket mounted on the engine and two hose clamps holding the HX to the bracket.  Newer M25XPs come with two brackets welded on to the HX.

Here's the broken bracket, and the new bracket installed with the old HX.  The rubber tube is chafe protection.  When the old bracket let go, the HX banged into the sharp edge of the remaining portion of the bracket left on the engine.

[Stu Jackson]

The pictures show:

-- Old & New
-- new elbow from 3/8" NPT at raw water pump to HX with new 5/8" hose to match the HX inlet port (our old hose and elbow was 1/2" while the HX was 5/8" so somebody cobbled it together wrong all these years!!!)
-- the gouges in the old HX
-- new HX installed showing clearance below the exhaust riser (better than Ron's Dollar Bill test!!! )

[Stu Jackson]

and

[Stu Jackson]

and

[DaveM]

Stu

That label looks just like the label on the Seakamp heat exchanger I mentioned

Good Winds
DaveM

[Stu Jackson]

Added to Engine tech wiki.

Dave's is a great, inexpensive source.

Ken, I think the body is copper, not brass (a non-marine-friendly material).

[Ken Juul]

Copper is even easier to fix.   Propane torch and solder.