1971 mercury model 1150 thunderbolt 115hp

[wbeckelman]

I recently received this engine on a 17ft shallow draft hull . got little or no info concerning it's condition.It's been sitting for two years,but engine ran prior to owners death 2 years ago says his son.
I have performed a compression test and all cylinders are at 120 lbs.
have replaced all spark plugs and all get spark so secondary ignition appears to be functioning .
electric choke wiring must be faulty because I applied 12volts to the choke
and it functioned properly so i need to add some wiring.
I'm replacing a lot of the wiring because there's a lot of insulation dryrot.
Question: is it possible to show water pump impeller condition When just cranking engine ? should i get a water exhaust indication by just cranking the engine ? The lower end of engine is submerged in a water tank.
I have downloaded a repair manual for this motor so it will help a lot.
my experience has been with 4stroke auto engines and i know i'm dealing with a new animal.

 

[latin monkey]

Re: 1971 mercury model 1150 thunderbolt 115hp

not knowing the condition of the impeller, i would replace it first. after sitting that long it should be replaced anyway and you don't want to send pieces of it up through your motor

 

[wbeckelman]

Re: 1971 mercury model 1150 thunderbolt 115hp

can I remove lower end and rebuild the water pump with the engine mounted on the boat transom ?
thank you, bill B.

 

[emckelvy]

Re: 1971 mercury model 1150 thunderbolt 115hp

can I remove lower end and rebuild the water pump with the engine mounted on the boat transom ? thank you, bill B.

You certainly can, it's easier that way anyhow. Just tilt the motor up to gain clearance for removing the lower unit.

Don't shift the remote control box once you have the L/U removed. It must be in the same position (whether that's Fwd, Neutral, or Reverse) for reinstallation.

Don't mess with the shift shaft in the lower unit, either. As long as you don't disturb the position of the shift shaft while you're working on the pump, you'll ensure that the upper shift rod is properly aligned with the L/U shift shaft upon reassembly and you'll have all your gears as before.

HTH........ed

p.s. don't forget about the hidden bolt under the trim tab. The trim tab bolt is accessed via a hole directly above the tab.

 

[wbeckelman]

Re: 1971 mercury model 1150 thunderbolt 115hp

Thanks ED.
Bill B.
What new parts should I have available when replacing empeller and can you suggest a reasonable source for these parts?
I'm in northern california, near Redding.

Bill B.