mercury identification

[kenmyfam]

I am at a friends house and am trying to identify his mercury 850. I am a Johnson 140hp owner and have never had a Mercury. Can not find an identity plate other than the serial number which is 7071593
Any help would be appreciated as we need to order water pump, thermostats if it uses any etc. Any help would be appreciated.
Thank You,
Ken

 

[Laddies]

Re: mercury identification

It's a 1976 Canadian built engine

 

[Chris1956]

Re: mercury identification

Ken, The waterpump actually impeller repair kit is pretty much standard and fits the 70-90s 4 and 6 cylnder motors. That motor also does not have a thermostat. The telltale water stream should not be warm at idle on the hose.

 

[kenmyfam]

Re: mercury identification

Ken, The waterpump actually impeller repair kit is pretty much standard and fits the 70-90s 4 and 6 cylnder motors. That motor also does not have a thermostat. The telltale water stream should not be warm at idle on the hose.

Thank You for that.
We ran it on the hose last night and the telltale was warm. I thought that was a problem so we shut down. Compression is good on all 4 cylinders and pretty even. Motor starts and ran well for the time we ran it. I guess I will tell him to order up a full waterpump / impeller kit and I will get busy on it for him. Unless anyone has any other ideas as to why ???
I will change the water pump stuff anyway but should I be looking at anything else ???
One more thing. He tells me when he did run it the once that he had it on his boat that it ran good for about 5 minutes and then dropped to an idle by itself. Does this motor have the "safe" mode and did it shut down to that to save an overheat ???
He is currently running his 65hp on his boat till we get this sorted out.
Thank You,
Ken.

 

[Chris1956]

Re: mercury identification

Kenny, That motor does not have a "safe mode". If the fuel pump(s) is not working properly, they will drop to idle. That motor may have a single fuel pump mounted on the lower cowl or dual fuel pumps mounted on the upper and lower transfer covers.

 

[kenmyfam]

Re: mercury identification

Kenny, That motor does not have a "safe mode". If the fuel pump(s) is not working properly, they will drop to idle. That motor may have a single fuel pump mounted on the lower cowl or dual fuel pumps mounted on the upper and lower transfer covers.

Thanks for that. I will be looking at this motor again later this week. Will report what I find.

 

[kenmyfam]

Re: mercury identification

One more thing. The outlets half way down the shaft were not putting anything out. On my Johnson 140hp they spray some when on the muffs and pour out when cruising. Should this Mercury do the same thing ????
Thanks for any and all info or advice.
He has ordered the water pump assembly and I should be installing this weekend.
Ken.

 

[Chris1956]

Re: mercury identification

Ken, Most of the cooling water will come out the gratings above the A-V plate, above and behind the prop. Some water will alos come out the prop hub. Water may or may not come out the holes at the base of the powerhead, on the muffs.

 

[kenmyfam]

Re: mercury identification

Ken, Most of the cooling water will come out the gratings above the A-V plate, above and behind the prop. Some water will alos come out the prop hub. Water may or may not come out the holes at the base of the powerhead, on the muffs.

Thanks for the info Chris. Hopefully the parts will be here for the weekend and we can get this done and tested. I have no Mercury experience whatsoever so all the info is a great help. Are there any other items I should be checking while I am over there doing this ???
Thanks again,
Ken