old 115 inline 72 or 73

I Don't Know Anything A Bout Old Mercs, But I Acquired A Good Running Old 72 Or 73 Merc 20 Inch, Thunderbolt Ignition It States. Serial Number 3114309. Is This A Good Motor Performance Wise, Or Just An Old Fishing Motor That Will Be Riddled With Issues? It Is Really Clean.

If It Would Be Decent On A Performance Boat, What Weight Of Boat, What Kind Of Topend, And What Did It Compete Against Back Then? Did Merc Have Bigger Motors At That Time (150?)?

Trying To Figure Out If This Is Worth Throwing On A Little 15 Foot Padded V For The Summer. They Look So Good.

Thnaks A Bunch.

Ronny
410 394 9000

Yes, in 72 the biggest motor was 140 and in 73 150, so the 115 is the little brother. Your serial number is a '71. Does it have red decals or blue?

Older inline Mercs have problems with decaying insulation on the internal wiring harness and corrosion on the water cooled exhaust divider.

On a very light boat with a good prop you should be able to see 50 mph, but speeds in the 45 mph range are more common.

i got 67 mph on a gps with an old flatback 115 crossflow. should i see similar top end with the 1971 115 inline or not?

also, two "old school" mechanics told me something that was a little different from the other. one said to run 89 octane and no need to touch the timing. the other said to run 93 and back it down a couple degrees. any thoughts? where do you get new decals for these things or do you use paint? thanks guys. really enjoying this site, especially compared to some other sites. this one is my favorite. it has less fluff.

If your boat is light enough to go 67 with a V-4 you should be OK with stock settings if you go over plane very quickly with the inline. I'd use the 93 and never let it labor going over plane ... use a tach and keep it propped to turn 6,000 instead of 5,500

Whether the inline 115 goes as fast as the V-4 probably depends on the year of the V-4

it was a 76 115, nothing special, $200 motor. flatback, totally stock.

is it worth adding the 135 carbs? friend of mine told me that is an easy 3-5 hp. any truth to that? where do you get those carbs?

Unless you replace the 115 reed blocks with 135 blocks, I don't think you will notice any difference with just the installing 135 carbs.

Anyone Know The Weight Of These? Wheres The Best Deal On A Wiring Harness On This? Thanks

The weight is around 300. CDI has wiring harnesses