Chrysler impeller housing question

[scotiany]

I'm trying to make 1 good LU out of 3 questionable ones. 2 of them have impeller housings with 3 mounting screws and 1 has 4 mounting screws. They all seem to fit into the LU. I just want to know if they are interchangeable. They all have the same impeller. The one with 4 screws is what I'd like to use because the drive shaft seal in it is available for replacement.

 

[eurolarva]

Re: Chrysler impeller housing question

Hey Scotiany. From reading your previous posts you know a lot more about chryslers than me. I dont know if this is useful or not. My 45 chrysler 1967 water pump has four holes in it however the lower unit only has three holes in it. It has been running good for me for over three years with only three screws in it. The plate below the water pump also has 4 holes in it. Ive got to think it isnt going to matter if you use the other hole.

 

[scotiany]

Re: Chrysler impeller housing question

Hey eurolarva , that's what I wanted to hear. Does yours have a seal for the driveshaft. If so, I think we can use the seal that comes in the LU seal kit. Just might have to buy 2 kits.

 

[Terry H]

Re: Chrysler impeller housing question

You can always drill and tap that 4th hole for the bolt...1/4" 20 thread...just a Thought

 

[eurolarva]

Re: Chrysler impeller housing question

Hey Scotiany. If memory serves me correct you have a 55hp chrysler. My Clymer shows a different water pump for your motor than mine(45HP). Mine has what is called a pump seal where the 55 has a drive shaft seal. I know they are different part numbers. You can check this web site. http://www.mercruiserparts.com/SelectModelType3.asp?class_id=2 <br />I think the part number for your drive shaft seal is 26-F474736 and cost about 5 dollars. The other difference is that the 55hp has a gasket under the back plate where mine does not. I am willing to bet who ever had the lu that has 4 holes instead of three drilled and tapped the fourth hole. Not sure why chrysler dosent use this hole but I doubt you will have a problem using this Lower Unit. As I mentioned mine has been around since 1967 and has been running on three mounting screws and not messed up

 

[scotiany]

Re: Chrysler impeller housing question

hey eurolarva , thanks for that info.I'm going to try the 4 hole pump first . Judging by what you say, I think I'll be OK. I checked another 55 lower unit- it had the 3 hole pump housing. I'm thinking it doesn't matter that much.