Mercury 700 1978

jschrift

Recruit
Joined
Feb 20, 2007
Messages
3
Hi all I am looking for some suggestions/help. I bought a Merc 700 last year off a guy for 200$ all he could tell me about it is when he last had it out it would rev really really fast and then when put into gear it seamed to die. I dont know a whole lot about engines but that didnt sound good but I am thinking of rebuilding it. Does it sound worth while? I just put a compressin tester in the spark plug holes and I dont know if I am doing something wrong because nothing is hooked up gas, water, ignition nothing. But I am only getting like 15lbs per cylinder. Two of the spark plugs appeared normal the third appeard brand new as if gas never touched it. I plan on tearing into this thing deeper and seeing what the pistons look like but I am just wondering if its worth it. The motor looks brand new was well kept and I just drained the oil out of the lower unit and it appeared almost perfect. I found a rebuild kit that appears to have about everything for 500$ is it just not worth it or could it be a worth while project. Thanks so much.

Jeff
 

crem1

Petty Officer 1st Class
Joined
Aug 30, 2005
Messages
365
Re: Mercury 700 1978

Hi!

Paying two hundred bucks for it sounds like a good investment. Compression check is a must, but I would do it with the battery attached and cranking it for couple of seconds. This might give you a better compression reading.
If the readings are still low then I would check the piston rings and cylinders.
Hope this helps

Alex
 
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