just inherited a '71 merc 1350, trying to bring it back to life

519deputydog

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Aug 2, 2012
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Where do I start. My 17 year old son brought this boat home, No history on if it runs, when it ran last etc. etc. I looked on-line and the VIN number says its a 1971 mercury 1350. I thought we'd throw a few bucks at it and see if it runs. So far we rebuilt the fuel pump, and all 3 carbs, and replaced all fuel lines.

Last night it fired up and ran for 10 seconds at a time before quitting again. We had it run like this several times but wouldn't stay running. I have read several posts, and adjusted the idle screws to 2 turns out. I'll try again tonight, where should I look next?

Thanks,

Ken B.
 

Chris1956

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Mar 25, 2004
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Re: just inherited a '71 merc 1350, trying to bring it back to life

Ken, Take a compression test and a spark test. Now inspect the engine wiring for condition. If all is good, clean carbs and rebuild them with new parts. Initial setting is 1-1/2 turns open.
 

jimmbo

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Re: just inherited a '71 merc 1350, trying to bring it back to life

When you said 'rebuilt the fuel pump' did you mean both pumps? That engine has two, in series.
 

Faztbullet

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Re: just inherited a '71 merc 1350, trying to bring it back to life

If compression is less than 125psi per cylinder quit throwing money at it as its wore out. That motor new fractory ran 140-150 psi...
 

Chris1956

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Re: just inherited a '71 merc 1350, trying to bring it back to life

I recommended you rebuild the carbs. It has three of those. As long as the compression is the same on all cylinders, the motor is serviceable. Fazt seems cranky today.
 

wired247

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Re: just inherited a '71 merc 1350, trying to bring it back to life

He rebuilt the carbs already. Floats might be off. Don't listen to me though . I cant get mine to run even after a complete rebuild.
 

Team Skelty

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Jul 19, 2012
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Re: just inherited a '71 merc 1350, trying to bring it back to life

Where do I start. My 17 year old son brought this boat home, No history on if it runs, when it ran last etc. etc. I looked on-line and the VIN number says its a 1971 mercury 1350. I thought we'd throw a few bucks at it and see if it runs. So far we rebuilt the fuel pump, and all 3 carbs, and replaced all fuel lines.

Last night it fired up and ran for 10 seconds at a time before quitting again. We had it run like this several times but wouldn't stay running. I have read several posts, and adjusted the idle screws to 2 turns out. I'll try again tonight, where should I look next?

Thanks,

Ken B.

I'm currently in the same situation. Traded for a boat that had a '70 merc 135 on it. Will run for a little longer, but dies as well. HOWEVER, if I keep constant pressure on the fuel line bulb, it will stay running. My guess is , I /you have a leak in the fuel system. If it looses pressure, won't run since the mechanical pump setup doesn't pull enough pressure to feed it when there is a loss of vacuumm. Recheck all your fuel lines and the quick connect. At least that's where I'm gonna start....
 

519deputydog

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Re: just inherited a '71 merc 1350, trying to bring it back to life

OK, I spent the day fixing up the wire connections, corrosion, grease, etc. etc. I took your advice and looked into the fuel system. I missed a gasket on the top of the fuel filter housing and was sucking air. The connections to the tank looked a little shady as well. Fixed all that up, and it actually started and ran for a few minutes. I had to turn the key off to shut her down. I went to fetch my phone to capture it on video, since no one else was home. Then I couldn't get it to start up again, I think its flooded now...:facepalm:

I did notice gas was dripping out of the front face of the carburetors...Is that because i messed up the carb rebuild? or just because the idle screws are out of adjustment?

I didn't see any water coming out of the tell-tale hose, but I was trying to use muffs/garden hose and it wasn't working well. I'll try using a big pail tomorrow.

Thanks for the advice guys...I'll need some more yet, I'm sure...

Ken
 

519deputydog

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Aug 2, 2012
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Re: just inherited a '71 merc 1350, trying to bring it back to life

OK, I spent the day fixing up the wire connections, corrosion, grease, etc. etc. I took your advice and looked into the fuel system. I missed a gasket on the top of the fuel filter housing and was sucking air. The connections to the tank looked a little shady as well. Fixed all that up, and it actually started and ran for a few minutes. I had to turn the key off to shut her down. I went to fetch my phone to capture it on video, since no one else was home, and they wouldn't believe me. Then I couldn't get it to start up again, I think its flooded now...:facepalm:

I did notice gas was dripping out of the front face of the carburetors...Is that because i messed up the carb rebuild? or just because the idle screws are out of adjustment?

I didn't see any water coming out of the tell-tale hose, but I was trying to use muffs/garden hose and it wasn't working well. I'll try using a big pail tomorrow.

Thanks for the advice guys...I'll need some more yet, I'm sure...

Ken
 

Charlie61

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Jul 27, 2011
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253
Re: just inherited a '71 merc 1350, trying to bring it back to life

sometime it hard to get the card just right I had to redo two of mine the flow where leaking gas : where not closing. do not forget to rebuild water pump motor over heat very fast
 

519deputydog

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Aug 2, 2012
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Re: just inherited a '71 merc 1350, trying to bring it back to life

OK, it runs for a few minutes then quits and wont restart. Almost like when it warms up, something bad happens. I was assuming fuel problems, and seen spark on the outside of the coil when it was running. Today I unhook the coil to inspect, and find its in 10 pieces, complete with scotch tape from the PO holding it together. Obviously I need a new one but its a $200 part. hmmm any advice....

Ken
 

wired247

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Re: just inherited a '71 merc 1350, trying to bring it back to life

Its a coil. a $35 parts store coil does the same thing. Mines got ONE of those little $25 Johnson V4 coils on it fed by 200V from the switch box. Goes sparky, sparky just like one of the huge factory coils does. I even tried one of those fancy MSD coils on it once. Went sparky sparky too.
 

Chris1956

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Mar 25, 2004
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Re: just inherited a '71 merc 1350, trying to bring it back to life

Deputy, Those coils are more like $25 and are avail from sierra and others.
 

519deputydog

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Aug 2, 2012
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Re: just inherited a '71 merc 1350, trying to bring it back to life

Thanks, I priced one website at $180 plus shipping. You guys are already saving me precious dough. Next question. How about spark plug wires? Do I need mercury spec marine plug wires, or will car type wires do the same thing?

Thanks,

Ken
 

519deputydog

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Aug 2, 2012
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Re: just inherited a '71 merc 1350, trying to bring it back to life

I need to get at the water pump and see what's going on in there. I have no water coming out when it does finally start. I read somewhere here to put the motor in reverse gear before dropping the lower unit, to avoid messing up the shift mechanisms during re-install. True or false?....any other advice?

Ken
 

519deputydog

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Joined
Aug 2, 2012
Messages
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Re: just inherited a '71 merc 1350, trying to bring it back to life

I need to get at the water pump and see what's going on in there. I have no water coming out when it does finally start. I read somewhere here to put the motor in reverse gear before dropping the lower unit, to avoid messing up the shift mechanisms during re-install. True or false?....any other advice?

Ken
 

Chris1956

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Joined
Mar 25, 2004
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27,030
Re: just inherited a '71 merc 1350, trying to bring it back to life

Put the motor in neutral before dropping the gearcase. Tilt the motor all the way up. There is a hidden bolt under the zinc anode. Replace the inpeller, wearplate and two gaskets. Inspect the upper pump cover stainless insert for scratches. Replace if you find them.

Merc spark plug wires screw into the dist cap. They are stranded stainless connectors. You can get replacements for $6-8 each on the web.
 

519deputydog

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Aug 2, 2012
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Re: just inherited a '71 merc 1350, trying to bring it back to life

OK, now what?

I pieced together the old coil just to continue with the troubleshooting and lo and behold it runs. runs good too. Just for laughs I put it in forward gear, no problem. When I tried reverse, it made an awful sound, and now its stuck in reverse gear. Obviously something broke. How do I free it up, to remove the lower end to have a look.

Thanks guys!

Ken B
 

Mi duckdown

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Apr 14, 2007
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2,575
Re: just inherited a '71 merc 1350, trying to bring it back to life

Remove the Lower end drain and vent screws and REPORT what comes out.
 
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