[EXTERNAL] [C400] Impeller Change


Ken
 

Stefan,

I was referring to galvanic corrosion within the end cap assembly.  I don't believe Rydlyme or Barnacle Buster would have much of an effect on the dissolution of metal.  The link is attached this time hopefully.


Stefan Damstrom
 

I watched a YouTube channel today on using Barnacle Buster (1:4) with fresh water and routing the raw water hoses to a small bilge pump in a bucket with this solution.  By running this for an hour, the mild acidic solution was able to clean the heat exchanger and I water, it would likely make it easier to remove in the future. 

 

Agree Ken that it should be a regular maintenance item including making sure each of the tubes is clear.

 

Ref: https://www.youtube.com/watch?v=cUBRAgGz3As&t=1s

 

From: Ken
Sent: Monday, June 28, 2021 3:28 PM
To: C400@Catalina400-445.groups.io
Subject: Re: [EXTERNAL] [C400] Impeller Change

 

Since Nick raised the subject of avoiding removing the end caps on the heat exchanger as a bonus, allow me to be a Debbie Downer for a moment.  I'm a firm believer in removing the Yanmar end caps every 2 years when you change coolant.  That heat exchanger end cap assembly was installed dry, meaning no galvanic protection paste was applied to any of the parts. Warm sea water, copper, aluminum, bronze, nickel and steel are in that mix.  In this forum I've read a few times how hard it was to remove the tube stack, had to use a hammer and a block of wood to remove...your periodic maintenance is lacking.  That tube stack should slide right out.  But typically the aluminum casting on the end of the heat exchanger is the first to go.  Here's an article on the subject from Tony Athens, a Cat diesel guru, but the concept and materials of construction are the same.

 


--
Catalina 400 MKii #190
Bellevue, WA 


Ken
 

Since Nick raised the subject of avoiding removing the end caps on the heat exchanger as a bonus, allow me to be a Debbie Downer for a moment.  I'm a firm believer in removing the Yanmar end caps every 2 years when you change coolant.  That heat exchanger end cap assembly was installed dry, meaning no galvanic protection paste was applied to any of the parts. Warm sea water, copper, aluminum, bronze, nickel and steel are in that mix.  In this forum I've read a few times how hard it was to remove the tube stack, had to use a hammer and a block of wood to remove...your periodic maintenance is lacking.  That tube stack should slide right out.  But typically the aluminum casting on the end of the heat exchanger is the first to go.  Here's an article on the subject from Tony Athens, a Cat diesel guru, but the concept and materials of construction are the same.


Frank Falcone
 

Hi Nick:

 

…GREAT INFORMATION! Thanks so much.

 

Regards,

Frank,

SILVER EAGLE, #247

 

From: C400@Catalina400-445.groups.io <C400@Catalina400-445.groups.io> On Behalf Of nick walker via groups.io
Sent: Monday, June 28, 2021 10:09 AM
To: C400@Catalina400-445.groups.io
Subject: Re: [EXTERNAL] [C400] Impeller Change

 

Hi all,

 

A few years ago, I opened the pump and found several blades missing so went looking.  I found them all, plus many more from POs losing blades all lodged in the inlet the oil cooler at the rear of the motor.  That's the first restriction after the pump and is before the cooling water exchanger.  Much easier to check by taking the hose off there rather than the end cap of the main heat exchanger too which is a bonus.

 

Cheers,
Nick.

Divided Sky, #232


From: C400@Catalina400-445.groups.io <C400@Catalina400-445.groups.io> on behalf of Frank Falcone <frank.falcone@...>
Sent: Monday, 28 June 2021 9:32 PM
To: C400@Catalina400-445.groups.io <C400@Catalina400-445.groups.io>
Subject: Re: [EXTERNAL] [C400] Impeller Change

 

C400 Colleagues:

Yes, replacing the impeller on the C400 is a 'task from hell'. Every time I do it, I wonder who and how this 'set up' was designed and approved. Although, the Speedseal Cover makes removing and replacing the cover easier, it does not help in the  removal and replacement of the actual impeller. I use a set of 'hose pullers' to remove the old impeller. This year, I had to find a long stainless steel rod to use, with a hammer and block of wood to install the new impeller. It did not go on easily.  Contortions and 'boat yoga' were on full display. I know of no other way to change the 'set up' to make this routine maintenance procedure easier in the future.

BTW, if a couple of vanes (arms) were missing on your impeller, they're probably logged in the heat exchanger somewhere. ...might become an overheating problem in the future.

...any thoughts from others?

Regards,
Frank, SILVER EAGLE, #247

-----Original Message-----
From: C400@Catalina400-445.groups.io <C400@Catalina400-445.groups.io> On Behalf Of Andrew Massey via groups.io
Sent: Sunday, June 27, 2021 10:38 PM
To: C400@catalina400-445.groups.io
Subject: [EXTERNAL] [C400] Impeller Change


>> Finally got motivated to change the impeller on my Yanmar which I had been hesitating to do because of the location. All I can say is whomever designed this deserves a special place in hell. Getting the cover off wasn’t too bad but the lack of visibility and leverage that seemed to be mutually exclusive made a 10 minute job on previous boats into a multi hour ordeal with my arms battered looking like I had defensive wounds. The impeller had a couple arms missing and I replaced and used a Speedseal cover kit I had bought previously for the occasion which should make future changes easier (together with a good dousing of grease on the spline). Runs about cooler 5 deg  with the improved flow and a potential problem averted
>>
>> I may well do an access port for easier access as a future mod










nick walker
 

Hi all,

A few years ago, I opened the pump and found several blades missing so went looking.  I found them all, plus many more from POs losing blades all lodged in the inlet the oil cooler at the rear of the motor.  That's the first restriction after the pump and is before the cooling water exchanger.  Much easier to check by taking the hose off there rather than the end cap of the main heat exchanger too which is a bonus.

Cheers,
Nick.
Divided Sky, #232

From: C400@Catalina400-445.groups.io <C400@Catalina400-445.groups.io> on behalf of Frank Falcone <frank.falcone@...>
Sent: Monday, 28 June 2021 9:32 PM
To: C400@Catalina400-445.groups.io <C400@Catalina400-445.groups.io>
Subject: Re: [EXTERNAL] [C400] Impeller Change
 
C400 Colleagues:

Yes, replacing the impeller on the C400 is a 'task from hell'. Every time I do it, I wonder who and how this 'set up' was designed and approved. Although, the Speedseal Cover makes removing and replacing the cover easier, it does not help in the  removal and replacement of the actual impeller. I use a set of 'hose pullers' to remove the old impeller. This year, I had to find a long stainless steel rod to use, with a hammer and block of wood to install the new impeller. It did not go on easily.  Contortions and 'boat yoga' were on full display. I know of no other way to change the 'set up' to make this routine maintenance procedure easier in the future.

BTW, if a couple of vanes (arms) were missing on your impeller, they're probably logged in the heat exchanger somewhere. ...might become an overheating problem in the future.

...any thoughts from others?

Regards,
Frank, SILVER EAGLE, #247

-----Original Message-----
From: C400@Catalina400-445.groups.io <C400@Catalina400-445.groups.io> On Behalf Of Andrew Massey via groups.io
Sent: Sunday, June 27, 2021 10:38 PM
To: C400@catalina400-445.groups.io
Subject: [EXTERNAL] [C400] Impeller Change


>> Finally got motivated to change the impeller on my Yanmar which I had been hesitating to do because of the location. All I can say is whomever designed this deserves a special place in hell. Getting the cover off wasn’t too bad but the lack of visibility and leverage that seemed to be mutually exclusive made a 10 minute job on previous boats into a multi hour ordeal with my arms battered looking like I had defensive wounds. The impeller had a couple arms missing and I replaced and used a Speedseal cover kit I had bought previously for the occasion which should make future changes easier (together with a good dousing of grease on the spline). Runs about cooler 5 deg  with the improved flow and a potential problem averted
>>
>> I may well do an access port for easier access as a future mod











Frank Falcone
 

C400 Colleagues:

Yes, replacing the impeller on the C400 is a 'task from hell'. Every time I do it, I wonder who and how this 'set up' was designed and approved. Although, the Speedseal Cover makes removing and replacing the cover easier, it does not help in the removal and replacement of the actual impeller. I use a set of 'hose pullers' to remove the old impeller. This year, I had to find a long stainless steel rod to use, with a hammer and block of wood to install the new impeller. It did not go on easily. Contortions and 'boat yoga' were on full display. I know of no other way to change the 'set up' to make this routine maintenance procedure easier in the future.

BTW, if a couple of vanes (arms) were missing on your impeller, they're probably logged in the heat exchanger somewhere. ...might become an overheating problem in the future.

...any thoughts from others?

Regards,
Frank, SILVER EAGLE, #247

-----Original Message-----
From: C400@Catalina400-445.groups.io <C400@Catalina400-445.groups.io> On Behalf Of Andrew Massey via groups.io
Sent: Sunday, June 27, 2021 10:38 PM
To: C400@catalina400-445.groups.io
Subject: [EXTERNAL] [C400] Impeller Change


Finally got motivated to change the impeller on my Yanmar which I had been hesitating to do because of the location. All I can say is whomever designed this deserves a special place in hell. Getting the cover off wasn’t too bad but the lack of visibility and leverage that seemed to be mutually exclusive made a 10 minute job on previous boats into a multi hour ordeal with my arms battered looking like I had defensive wounds. The impeller had a couple arms missing and I replaced and used a Speedseal cover kit I had bought previously for the occasion which should make future changes easier (together with a good dousing of grease on the spline). Runs about cooler 5 deg with the improved flow and a potential problem averted

I may well do an access port for easier access as a future mod