Can someone walk me through replacing the impeller on a merc 233. Ford block.
Id like to replace them before dropping in in3 weeks.
Impeller replacement
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Impeller replacement
1974 f32 Sedan
Twin 233 Mercruisers
Twin 233 Mercruisers
- P-Dogg
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Re: Impeller replacement
Good info here: http://bfy.tw/Mpo4
I needed a less expensive hobby, so I bought a boat!
- prowlersfish
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Re: Impeller replacement
Can you get to the back plate easily ? I will try and describe the replacement . Its not hard but some times you have to pull the pump ( always mark up and down . )
Boating is good for the soul
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat

- prowlersfish
- 2025 Gold Support
- Posts: 12723
- Joined: Sat Nov 05, 2005 6:56 pm
- Location: Lower Chesapeake Bay ,Va
Re: Impeller replacement
I have done hundreds of times , 233 mercs used 2 style pumps , I am going to assume yours is the type with the flat rear cover . Remove the rear cover (on or off the engine as needed) after you get the cover off , note if all blades of the impeller are there ( if not you need to find them ) spry something like WD 40 in the center area . it may help t spray the impeller too . If you have a impeller puller great if not . Carefully with 2 screw drivers try and pry the impeller out , using care not to damage the sealing/gasket area . Watch for a key that may fall out ( some are splined not keyed) . inspect the pump for wear . To reinstall make sure the key way is installed (if it has one ) lube up the new impeller , I like dish soap . turn / twist the impeller lining up the key to install . Reinstall the cover with a new seal/gasket . reinstall the pump if removed .
One note do not worry what way the impeller blades are turned . As soon as you turn the engine over they will flip the right way .
Boating is good for the soul
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat
