Beta 25 re-power: some plumbing issues

[Patches]

My new Beta 25 is in the boat, bolted down, and engine aligned.  Hooking up the plumbing now and there are some clear differences from the old plumbing for the M25-XP that it replaced.  In searching prior threads, nobody seems to cover these.  Among them:

1.  M25-XP utilized 5/8" raw water supply; Beta 25 utilizes 3/4".  This was solved for the time being by purchasing a new Vetus knock-off strainer with "progressive" barbs (1/2", 5/8", and 3/4").  I was able to keep the 5/8" intake from the thru-hull under the head sink but cut the "outflow" on the strainer to the 3/4" barb and ran new 3/4" hose to the raw water pump.

2.  On the back end, the M25-XP had a 5/8" hose going to the anti-siphon loop, and then 5/8" to the injection nipple in the 1 5/8" exhaust riser.  The Beta 25 has a 1" barb off the heat exchanger.  To accommodate the existing Catalina 34 wet exhaust infrastructure, this needs to be reduced down to 5/8" before the anti-siphon loop.  Again, nobody seems to have mentioned this.

3.  The exhaust flange on the M25-XP is 1 5/8" (OD), and on the Beta 25 is 2".  This required a reducer, and then a welder to cut and reduce the length of the 1 5/8" pipe coming off of the Engine exhaust flange (to accommodate the length of the reducer).

So there are some clear plumbing differences which need to be sorted.  The one I dislike the most is the reduction of the water supply from the the heat exchanger to the injection nipple on the exhaust riser (1"> 5/8").  Although I haven't actually fired everything up yet (I was sent the wrong alternator--I am set up for external regulation to my Firefly battery bank and was sent a 120 amp alternator with internal regulator) I'm thinking a wet exhaust overhaul might be in the future.

Hoping to post later with photos and modifications needed.

Patches

[waughoo]

So glad to hear you are this far along.  I was at Blakely Harbor for an overnight last friday/Saturday and was wondering about your progress on my way back.

[Ron Hill]

Patches : Just make sure that the hose from the vented loop to the riser nipple is made of Felixable NYLON and not wire reinforced!!  TOOOO hard on that nipple weld - from the engine vibration!!

A thought

[KWKloeber]

I'm thinking a wet exhaust overhaul might be in the future.

if so consider a water-cooled exhaust riser.

Wasn't the exhaust flange 1-1/4"?  The iron pipe heat riser OD would then be 1-5/8", which equalled the exhaust hose's 1-5/8" ID.

[Patches]

I ended up rebuilding part of the exhaust system to accommodate the new Beta 25 exhaust requirements.  I had to remove the the sink bowl in the head  to complete all of the work below.

1. I replaced the 5/8" anti-siphon loop under the head sink with the 1" loop supplied by Beta.  A tighter fit, but it fits.

2. The stainless steel exhaust riser I previously purchased from Catalina Direct was modified by a welder to accommodate a 1" injection nipple from the anti-siphon loop and a 2" (ID) exhaust outlet per Beta specs.

3.  I removed the old (original) aqualift muffler and replaced it with a new Vetus NLP waterlock muffler.  I can't recommend these mufflers enough because the inlet and outlet can be adjusted to accommodate just about any angle of entry from the riser and exit to the exhaust hose.  And they are relatively cheap ($225 at Fisheries Supply)  Two of the best upgrades I have made are to go with the Vetus raw water strainer and NLP muffler.

Removing the original Aqualift muffler is a bit of a pain, but doable.  In their infinite wisdom, Catalina decided to mount the muffler mostly under the aft cabin bed.  It is held down by 4 screws to a wood platform that is level and glassed to the hull.  Once removed, the new Vetus muffler would not fit completely on the old platform--due to constraints built into the exhaust riser location, beginning of the 17' exhaust hose run, and height and method of securing the new Vetus muffler. So I cut a second platform from 3/4" plywood and mounted it to the old platform such that it protrudes forward a little more forward into the head compartment.

From there it was a matter of getting all the angles right for the input from the exhaust riser.  I purchased two 4" hump hoses on Amazon and connected them with a 3" length of fiberglass exhaust tubing.  I think the cost was $20-25 versus the $$$ for the hump hose that CD sells.  The 8" length was perfect for the distance from the exhaust riser outlet to the new Vetus muffler.  Because of the way you can adjust the inlet and outlets on the Vetus muffler, everything lined up perfectly.  With the old CD hump hose and original muffler, things worked because of the flexibility of the hump hose, but they were always a little askew, or misaligned. 

4.  I kept the existing 1 5/8" exhaust hose because I had replaced it about a year ago.  So I purchased a Vetus progressive reducer to make the reduction from the 2" outlet on the new muffler to the existing 1 5/8" exhaust hose.

5.  I used a short length of 1" heater hose from Napa to go from the anti-siphon loop to the injection nipple. The Trident "Flex" was not flexible enough.

Overall, the system is much improved. 

Photos when I get a break from chartering--which is very busy right now.

Patches