Which outboard to choose

I have an opportunity to buy two different outboards. Both are late 70s models of similar HP ratings and will be used on a 24 foot pontoon boat. One is a Mariner inline 6 and the other is an Evinrude V4. The Mariner looks to have been well cared for but the more I look at it the more the design scares me. The Evinrude I'm more comfortable with as I'm running a straight 3 now. I will be doing a test run (on the muffs only) and a compression check on both motors.

Assuming they both check out which brand, more over design, would you buy.

I'm positing this here to avoid the OMC forum saying the Evinrude and the Mercury forum saying the Mariner.

Difficult to answer from afar. The compression test should be your best guide - that with the best compression should be most considered. Also, a leak down test should be performed on each engine. As a general observation, the old Evinrudes have a good reputation if well maintained.

That is my sense of the Evinrudes as well. I have a 1977 70 HP on the boat now and after a bit of a learning curve I have it running really well I just want more power and the boat is rated for up to a 115. It'll be a back up motor when I get the new one.

The Mariner uses a distributor which is one issue that gives me pause, CD ignitions are just plain better other then the repair cost, but moreover the reed cages being installed on the crank bothers me. If I have a reed problem it's a complete tear down. Maybe that is a silly concern.

The inline 6 are a wonderful running motor.----The big concern is the cost of rebuilding one of those.----More and $$$$ parts are needed for the 6 cylinder compared to the 4 cylinder OMC.----------Cost of labour is the biggest concern if you have to have work done at a shop.

New guy here. I've run alot of 70's Johnson/Rudes and only had 1 over the years that had a mechanical issue. (stator and lower unit; repaired for $150)
I always put new CDI boxes (just me) on them and they were good to go.

Thanks for all the replies. I ended up buying the Evinrude last night. This one was close to me (the Mariner was 1.5 hours away one way) so I looked at it first and it checked out. Compression was good and the motor ran decent on the muffs. No weird noises, no blowing fuel out the carbs, shifted fine. Of course all that may change once it hits the water so we'll see.

The carbs need gone through and the it'll get a water pump and lower unit oil change. I hope it'll be a good motor. Bought the whole boat for 900. It's a 1977 Reinell that has seen better days, the hull is fine but the interior and all the plastic is shot. Not economical to save. I hate to do it but it'll be in the landfill here shortly and the trailer will go up for sale.