Impeller ISUZU 6BD1...Spring Maint. Question

[coolchange]

Hi all...Spring is on the way and I am getting ready.

I have, as stated above, an Isuzu 6bd1 and it has a Johnson raw water pump. The engine has only 190 hours since a full rebuild 2 seasons ago...going into the third with a pretty long trip up the B.C. coast on tap for the summer and don't want problems far away from home.

....how often are you all changing these impellers out?

...it looks like I need to move the Alternator then take off the cover plate to the pump (which faces to the stern)..but it also looks like it might be easiest to take the pump loose from its mount prior to taking the plate off.

Does anyone have experience with this engine and RW pump and if so can you give "best way" advice?

Thanks.

[whwells]

Coolchange: When do you expect to do the extended Puget Sound/BC run? I expect to do Port Hardy and Perhaps Desolation this year?
whwells "Howard"
2006 35te Sportfisher/Flybridge "Nibbles"
2004 Osprey Pilothouse 22 "Nest"

[coolchange]

Coolchange: When do you expect to do the extended Puget Sound/BC run? I expect to do Port Hardy and Perhaps Desolation this year?
whwells "Howard"
2006 35te Sportfisher/Flybridge "Nibbles"
2004 Osprey Pilothouse 22 "Nest"

Hi...should be leaving Belliingham in mid August for 3 weeks up to Broughtons..(most likely via Sunshine but maybe up the V. Island coast) then I will "dump" my cruise buddy on the way back and pick up my wife for another 2 weeks in SJ and Gulf Islands...

..We'll have to stay in touch

[jleonard]

Hi all...Spring is on the way and I am getting ready.

I have, as stated above, an Isuzu 6bd1 and it has a Johnson raw water pump. The engine has only 190 hours since a full rebuild 2 seasons ago...going into the third with a pretty long trip up the B.C. coast on tap for the summer and don't want problems far away from home.

....how often are you all changing these impellers out?

...it looks like I need to move the Alternator then take off the cover plate to the pump (which faces to the stern)..but it also looks like it might be easiest to take the pump loose from its mount prior to taking the plate off.

Does anyone have experience with this engine and RW pump and if so can you give "best way" advice?

Thanks.

I have a Lehman with a Johnson pump, but my answer is the same no matter what engine and what brand raw water pump.
I change my impellers every 2 seasons (once I went 3 seasons) no matter how many hours. I never had a failure and I don't want one. I believe that the raw water system is the most critical to engine cooling and health and the raw water pump is the heart of that system.
I have changed impellers both ways....sometimes by only removing the back cover, and sometimes removing the entire pump. It depends on the engine and your access, and maybe your ability to work somewhat blind with a mirror.
So I cannot advise you on that point other than if you feel the need to completely inspect the pump for seal leakage, etc it might serve you better to remove the pump.
Also it doesn't matter which way the impeller blades are facing when you put it in. They will properly orient themslves in the first revolution when you fire up.

[coolchange]

Tlhanks for the input...I found a "manual" on the engine and it says 3 years but I think I agree with you on the need for never losing the pump and will be doing it this Spring...by taking the pump out and over to a bench....looks like I have to almost take it off/apart anyway..and since I almost always drop something into the bilge this will likely be easiest.

[obertra9]

I have the 6BD1 in a 1990 A27 SC but the impellor is a Sherwood K90. I removed my entire pump assembly, glad I did because I found out I needed the major rebuild rather than the minor rebuild because the shaft and bearings were also bad. For me it was better to replace with a new pump (which I did) rather than do the major rebuild (which would have required access to a good arbor press). Caution, any air leak on the suction side will prevent pumping, so be sure your raw water strainer is also properly assembled.
Roger

[coolchange]

Coolchange: When do you expect to do the extended Puget Sound/BC run? I expect to do Port Hardy and Perhaps Desolation this year?
whwells "Howard"
2006 35te Sportfisher/Flybridge "Nibbles"
2004 Osprey Pilothouse 22 "Nest"

Howard: re the above ...plans now, and pretty firm, are that my wife and I will be coming to the "gathering" at Roche...then messing around in the SJs with a couple or friends who will be land based in Friday Harbor and then on the 17th my wife and his wife will ferry/drive back to Portland and Sid and I will take off for 3 weeks to head up to the Braughtons...working our way up via Vancouver and Sunshine Coast and returning through the Gulf Islands.

Any overlap??