MC Chevy V8 Bravo 1 Crankshaft water pickup pump issues

[tank1949]

Boat sat in my driveway for about 4 years due to health issues. When I put it up 4 years ago it ran very well. Both motors were about the 150-degree temperature range during sea trial. I am very familiar with Alphas, but it looks like former owner may have skimped on the best water pick up pumps. I am not familiar with these Johnson Crank Shaft pumps, but flukes on the impellers have totally disintegrated. Do these pumps require priming other than attaching a muff to OD? Must I add a lubricant to impeller housing at the beginning of the season? The impellers are easy to replace, much easier than Alphas. Do they wear out faster than Alpha impellers? Any feedback will be appreciated.

 

[04fxdwgi25]

If impeller was trashed, means it ran with out water. Those pumps are more reliable than the Alpha, pump more water and are much easier to change / maintain.
Are there thru hulls for water pickups? Sometimes they get added when when a Bravo drive water passage corrodes and blocks up and the drive raw water intake is bypassed.
Do you have a sea strainer before the pump? If yes, it needs to be clean and 100% full, and if running on a hose, hose needs to be on full before trying to start.

 

[tank1949]

If impeller was trashed, means it ran with out water. Those pumps are more reliable than the Alpha, pump more water and are much easier to change / maintain.
Are there thru hulls for water pickups? Sometimes they get added when when a Bravo drive water passage corrodes and blocks up and the drive raw water intake is bypassed.
Do you have a sea strainer before the pump? If yes, it needs to be clean and 100% full, and if running on a hose, hose needs to be on full before trying to start.

THX!!!! No strainers. No thru hulls. Water come in via gills/holes on lower OD unit and up through transom assembly and then down to pump. I use a

Quicksilver 44357Q2 Through Gear Case Flushing Kit. It is a bit more difficult to attach than clam shell type muffs. But, it also appears to attach to OD, stronger.​

We may not have had water pressure set to "Full." Before installing new impellers, I am going to attach kit again, with max hose water pressure and see if water makes it to pump.

 

[Scott Danforth]

impeller rubber goes off of calendar years, not operating hours.

impellers are easy to replace. sometimes you need to persuade the impeller out of teh housing. a dab of KY jelly on the impeller is all the lubricant it needs on first start. it does need to have the hose on full on the muffs or fake-a-lake to get the water to the pump.

 

[tank1949]

impeller rubber goes off of calendar years, not operating hours.

impellers are easy to replace. sometimes you need to persuade the impeller out of teh housing. a dab of KY jelly on the impeller is all the lubricant it needs on first start. it does need to have the hose on full on the muffs or fake-a-lake to get the water to the pump.

Ordered impellers. Next time I will disconnect hose at pump's body to be sure water is getting up and through intermediate housing and down to pump housing. According to Iboat forum member history, other Bravo 1 users have had similar problems. We never check for water at housing and like you implied; they are old at sat waterless for 4 years. Double whammy!