Mercury 850 re: Replacing complete lower unit assembly

[wguttrid]

Hi guys hoping someone might have the answer I am looking for.

I have an old Mercury 850 outboard engine (circa 73-77) and would like to replace the complete lower unit housing and assemblies.

Been browsing around hoping to come across and engine I can steal from but to expand my possibilities I was wondering if the lower unit for the 850 model might have been common with any other models.

Thanks again for all the help.

 

[wguttrid]

Re: Mercury 850 re: Replacing complete lower unit assembly

From what I gather is sounds like any 4 or 6 cylinder inline lower unit from early 70's to mid 80's will fit on my engine.

 

[Faztbullet]

Re: Mercury 850 re: Replacing complete lower unit assembly

The 4 cylinders are a 2.3to 1 ratio and the 6 cylinder is 2.1. It been posted that you can use a 2.1 on it and drop pitch to makeup for ratio but from what I have seen it makes them lazy on bottom end.

 

[wguttrid]

Re: Mercury 850 re: Replacing complete lower unit assembly

Faztbullet, thanks for the insight and help...going to try and find a Mercury 4 cylinder engine from 70's and mid 80's....will stay away from 6 cylinder all together.

 

[wguttrid]

Re: Mercury 850 re: Replacing complete lower unit assembly

Just got a line on a cheap Mercury 650 (1977')...hoping to look at it this weekend if I can fit the drive in schedule.

But here is what the owner is telling me about the lower end when I asked.
1.) Needs new prop and bearing.
2.) He thinks it is fine but looks like the shaft is pulled out might have a snap ring that came off.

He has offered me his garage and tools if I want to pull apart and check out.

Any thoughts, insights, things to look for? Or things to ask him?

 

[Chris1956]

Re: Mercury 850 re: Replacing complete lower unit assembly

I do not think that gearcase will fit your 850.

 

[wguttrid]

Re: Mercury 850 re: Replacing complete lower unit assembly

Ya....wondering the same thing....supposed to go look at it. Is cheap cheap so hoping it works as right now my current lower end is pretty much garbage..lol