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Any truth in it? 1970 400 40 hp

haventaclue

Outstanding Contributor
"The '70-'71 400's were rogue engines & there is a story that Carl Kiekhaefer wanted to recall them all & crush them. True or not, who knows?"
I read this on another forum and I was wondering if there was any truth or even a smighin of fact in it.
 
Re: Any truth in it?

If you mean the Merc 402s, very possible. If you mean the 4 cylinders, no way!

Jeff
 
Re: Any truth in it?

It was a discussion on CMBA site in the UK.It was in relation to the 400 been called a crankbuster. A guy posted this and and give a very good explanation as to why they would break the crank,human error,wrong prop,under powered/too small a motor on the boat. It was the bit about "there is a story that Carl Kiekhaefer wanted to recall them all & crush them" I was wondering if there may have been a rumor to that effect over there.I'm just a nosy kinda fella.:)
But I would like to hear more about the problems with the 402,was this a 2cyl 40HP as the 400 was 4cyl.Just curious.
 
Re: Any truth in it?

Thought so! The 402 was big trouble. Later versions of the 35/ 40 hp twin were much better.

Jeff
 
Re: Any truth in it?

I've never heard that (specifically) myself, but like Jeff, saw this model, in all it's different versions as a "motor to avoid".

The 1970/71 model 400's (the 400 was only sold those two model years) introduced Merc's (new) 33.3 cubic inch, internal reed, 2 cylinder block.

The block itself stayed in production until 1989. Over that time it was used on the model 400, 402 and the 35 and 40 twins.

I never particularly liked these model 40's and Merc did play around alot with them trying to "get them right".

They started life with Merc's relatively new Thunderbolt 3 ignition (modular predecessor of the T4) and a sidebowl back-draft carb.

When they changed it to the model 402 they regressed and stuck on a phasemaker ignition.

In 1975 they upgraded that to the T4, but still retained the original carb.

In 1979 they renamed it simply the 40 Merc without making any changes.

For the 1984 model year they renamed it the 35 (which reflected the change from rating horsepower in BHP to SHP).

When the last 35 twin rolled off the line in 1989, it was still using Merc's oldest carb design.

But back to your original question - I checked the parts listings. The crankshaft for the model 400 sold for $390. The (new) crankshaft in the 402 first year of production sold for almost $800 - so either there was significant inflation between 1972 and 1973, or maybe there was some truth to what you heard :)
 
Re: Any truth in it?

..."For the 1984 model year they renamed it the 35 (which reflected the change from rating horsepower in BHP to SHP)."

Good point, Graham! Never thought about that before (even though I know the late, older design 60 hp triple was rated at 70 hp before re-rating).

Jeff
 
Re: Any truth in it?

Yes, by the 1986 model year all the (biggies) were rating in shaft horsepower. So in the mid-80's you ended up with some (weird) horsepower models - like a 185 Evinrude.

Only the 25 and 35 horse (in the twin cylinder models) survived the major model change in 86 (using the same block). The 18 horse was "tweaked" and became the 20 and the 25XD was rejetted to ensure the full 25 horses and the 35 simply reflected the SHP.

Thankfully they scrapped the 35 a couple years later, formerly the 40 which was resurected as the 4 cylinder model - probably one of the best powerheads of all time.

For anyone following along, the later model twin 40's were not the same engine in any respect to the 89/earlier models. The 40/30 "Marathon, Magnum (Merc/Mariner) or Sea Pro" twins that came out in the mid-90's were a very decent little motor.

They were relatively light for the horsepower (about 150 pounds - nearly 50 pounds lighter than the 4 cylinder models produced before this model run) had excellent carbs, a solid oil injection system, the best ignition system on the planet and the 39.3 cubic inch block was well suited to make 40 horses...
 
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