71/72 105hp Propeller Clearance Issue

[EvanB88]

I have a 1972 Chrysler 105, purchased with a cracked lower unit due to leaving it tilted up in winter without draining water.

I bought a used lower unit listed for a 1971 105. Installed it and everything bolted up. I had to get a longer bolt for the rear of the exhaust snout as the 72 used a short bolt instead of the 4-1/2ish for the 71. I used the old (13x17) propeller and after firing it up find out it hits the exhaust snout.

Measuring the clearance to the front of the exhaust snout recess on the old one I get 4-1/8". The new one that I mounted measures about an inch shorter.



I'm assuming there has to be a propeller that will work with the less clearance on the 71 lower unit but don't want to buy them randomly on hopes it will work out. Is there something specific I should look for to get a propeller that will work with this setup?

 

[Nordin]

Did the "new" LU come without the exhaust snout and you put the one from you cracked LU on it?
I know there were two different snouts and the later LU from mid 70:es hade a snout which was shorter and had a steeper shape.
When I check in my parts catalogs there are different part numbers.
A438116-2 (newer) and A369116 (older), check with Franz at Franz Marine Service he will figur it out for you.

 

[jerryjerry05]

When they went to the one piece lower unit they also changed the props.
You'll need to find the older style for it to fit.

 

[EvanB88]

They are both 2-piece lowers. I did use the exhaust snout from the cracked unit on the replacement. Looking at images the earlier part number is different than mine and appears that it may give the clearance required.