1975 440 sr

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goodaaydave
Posts: 4
Joined: Wed Dec 05, 2012 5:01 pm

1975 440 sr

Post by goodaaydave »

a new owner of a 1975 440 sr,won,t start,have spark ,compression 150,and fuel to cylinders,electric start,single carb,
Mercury
Posts: 225
Joined: Mon Sep 30, 2002 1:39 am
Location: USA

Re: 1975 440 sr

Post by Mercury »

Pull block drain bolts make sure crank area is not full of fuel.

Do you have spark under compression of just when the plugs are sitting on the cylinders?

With Gas off see if it will pop with some starting fluid.
goodaaydave
Posts: 4
Joined: Wed Dec 05, 2012 5:01 pm

Re: 1975 440 sr

Post by goodaaydave »

Mercury wrote:Pull block drain bolts make sure crank area is not full of fuel.

Do you have spark under compression of just when the plugs are sitting on the cylinders?

With Gas off see if it will pop with some starting fluid.
pulled vacuum hose of carb and yes gas came shooting out,will try some quick start tomorrow
Mercury
Posts: 225
Joined: Mon Sep 30, 2002 1:39 am
Location: USA

Re: 1975 440 sr

Post by Mercury »

You want to get all the gas out of the sump.

There are 2 10mm bolts, that act as drains, at the lowest point of the block. These should be removed. The engine should be pulled over several times with the key off to push the gas/water out of the block and then let sit with the bolts out overnight. Reinstall the bolts and give it a little squirt of starting fluid and see if it pops.

It is not uncommon for this to occur. Gas is leaking through the carb and filling up the crankcase. You need to rebuild the carb. If the feed line is still attached you will continue to fill the crankcase...to the point where it may empty the fuel tank. The fool proof method to eliminate this is an on/off inline valve in the fuel line before it links to the carb.

Bill
goodaaydave wrote: pulled vacuum hose of carb and yes gas came shooting out,will try some quick start tomorrow
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