7.5 HP Mercury question

Spillman1979

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Hello guys, My question is is this engine worth keeping and rebuilding? I'm not sure of the year of this if you guys can help that's great, and what is the availability of parts for this? The serial number is 3279038. Thanks and any info is appreciated , also what is kiekahfer mean?
 

racerone

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?---------Carl kiekheafer was the man who founded the company in 1939.
 

tpenfield

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It is a 1972 . . . I just rebuilt my 1969 7.5 HP.

IMG_9530B.jpg

Most of the parts are available. Some are new original stock (NOS) and some are just plain new.

For my rebuild, I bought . . .

- All the gaskets for the powerhead (new)

- Piston Rings (NOS)

- Main roller bearings (new)

- Upper Needle bearing (new)

- Trim Pin (new)

- Tiller Pivot Bolt (NOS)

- Decal Set (reproduction)

For the parts that are no longer available (NLA), you can always check eBay.

The thing that you might want to try to do (if not already done to the motor) is replace the carbon steel driveshaft with a stainless steel version. Mercury switched to stainless steel in 1979 +/-. I got a drive shaft from a 1980 motor to replace the one in my engine.
 

Spillman1979

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I was looking to replace ignition parts, I have spark on one cylinder, and wires from the stator are all ate up.
 

tpenfield

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The stator and the coils are available . . . You can re-make some of the simple wiring. The 1972 models went to the stator and coils whereas the earlier models had the magneto. It would be best to figure out what you need and price the parts out accordingly.
 

Yegboats

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?---------Carl kiekheafer was the man who founded the company in 1939.
Just wanted to add a little more to this b/c it ties in with your 1972 model. Mercury merged with Brunswick (yeap the bowling company) in 1961 Carl Kiekheafer stayed on until he resigned 1/31/1970 Mercury officially changed their name to Mercury Marine division of Brunswick in Nov. 1971. Since the 1972 models were already in production they still said Kiekhaefer. After 1972 and the name change they no longer said Kiekhaefer. For 33 years mercurys had Kiekhaefer on them.
 

tpenfield

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I was looking to replace ignition parts, I have spark on one cylinder, and wires from the stator are all ate up.

An additional thought . . . depending on how good you are with wiring, soldering, etc. . . . if the wiring from the stator is chewed up, the issue may just be with the wiring and not the parts themselves. You could try the replace the wiring by splicing/soldering in new wires as needed.

The ignition parts are a bit pricey, so this approach could save some $$$ if the parts themselves are good.
 

Spillman1979

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Wiring looks pretty bad, not sure if I can get into the plastic where the wires start. Does anyone know if that's possible? If not I will just buy new if I can find a part number.
 

racerone

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So many folks want to start with buying new parts.---------Do a complete evaluation of the motor before spending a single dollar !
 

Spillman1979

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I have done a compression check of both cylinders and they check out at 120 psi, I had great spark on 1 cylinder but not on the other probably due to those wires being bad. The lower end looks good also, I figure a carb kit, fuel pump kit and new stator , water pump and she's going to be running great. I could be wrong and this engine is not worth doing any of that. I will tell you I have nothing in this motor, I found in my dad's garage who recently passed away from cancer. I just want something for my 14ft smokercraft and this seemed like it would do the job.. I am open to any ideas.
 

tpenfield

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I would take the flywheel off and get at the stator and associated wiring. From there you can probably better tell what needs fixing. Anything can be done from a DIY perspective. If you start buying parts, you will probably over spend, and not really be worth it. You'll have $500 invested into a $300 motor.
 

racerone

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If this 45 year old motor has never been apart it will need new seals on the crankshaft.-Replace upper and lower seals for best idle performance !
 

Spillman1979

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Ok, guys came to the conclusion, after looking at rebuilding this motor and realized these parts are to expensive. I don't think I want to put this much money into it. Money would pron8be best spent towards a newer motor. What do you guys think?
 

tpenfield

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If you don't think you are up to it, then yes, sell it as a parts or repairable motor and put the money towards a working motor.
 

Spillman1979

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Do you guys know if I can find the white insulator blocks, for the stator on this engine.
 

60sboater

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I have a '73 9.8hp and replaced most of the ignition(all but the capacitor and trigger coil). It's a points/electronics system;in 74 they went to all electronic,CDI. CDI's site has t-shooting information. Don't throw parts at it if possible. As stated,try to find the cause of a particular problem....save money.

Make sure the wiring insulation can handle the high voltages.
 
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