1972 140 HP inline 6

[karmrd]

I am looking at 1972 140HP inline 6 to replace 100ESL72 Johnson. Anyone have experiance with this model. I posted this on Johnson forum by mistake. Hope I don't get anyone mad. I am sure they will let me know I screwed up.

 

[phatmanmike]

Re: 1972 140 HP inline 6

i own a 76 inline 115. what a beast! i love mine to death, but i cant afford to feed her anymore, so she has been sold on ebay to a fella with deeper pockets.<br /><br />that inline is the lightest pound(270) per hp and also the greatest cubic(99) inch per hp, so mercury was onto somthing there, eh!<br /><br />there is a forum online, that talks strictly about the inline mercurys.... in outlook express, go to TOOLS>ACCOUNTS>NEWS>ADD<br />the server name is news.kraits.org and the forum name is bigweek.mercury-inlines<br /><br />the inlines have no cylinder head. this can be a plus or a minus, depends how you look at it.<br /><br />parts are everywhere and they are about simple to work on and last a long time. mines 30 years old and still kicking strong

 

[Clams Canino]

Re: 1972 140 HP inline 6

Pound for pound that critter will eat the Jonnyrude for breakfast. Make sure you get a manual, clean the carbs, and that the maximum advance is set for 21 degrees - NOT the 27 on the sticker.<br /><br />-W

 

[karmrd]

Re: 1972 140 HP inline 6

Sounds like my kind of motor. No cylinder heads? I think i'll check out online forum you turned me on to for some details about that. Never seen a piston engine without heads before. I need to take a look at that for sure. I'll post it's performance after a couple tanks of fuel. I'd better pick up a third fuel cell just for the return ride to the ramp. Any suggestions for performance prop in case I find myself in a good drag for pinkslips? Any long term problems running a tank of CAM2 fuel through her once in a while just for fun? Love that extra power boost it produces when I'm feeling the need for speed and the wife and kids are safe at home. And the smell it produces gives me goose bumps and leaves the slow dudes dazed and confused. I run only CAM2 in my 100cc cart motor and my super cool '76 RD400 street bike that I found at the scrap yard only minutes from death by crushing. I paid the man $15.00 and he laughed at me as I drug it more than a 100yds over piles of scrap metal and into my truck. Took me about 2 hrs to do it. (I quit smoking the next day). I haven't seen any signs of cylinder scaring or piston melt down in either one of those super high reving strokers and I push them way past the limits. Should be safe to use in the Merc I would think. Anyone ever try it when nothing else seems to satisfy that urge to push the limit a little harder.

 

[Clams Canino]

Re: 1972 140 HP inline 6

I have a 25 gallon tank in my boat, and can drink that easily in a day of constant ski + tube play.<br /><br />The heads are cast into the block - blind holes.<br /><br />To remove a piston you pull the intake off and pull the entire reciprocating assembly out.<br /><br />As for gas - mid grade is reccomended, not sure if anything over 89 octane will do much for it.<br /><br />Since they make up to 1.5 hp per cubic inch, they tend to run thermally on the edge and as a result are a little "piston happy". They evolved from a race engine design, porting is already optimal.<br /><br />Props vary, but the Mercury High Five stainless is a great overall driving prop. <br /><br />Because of the age, I reccomend taking it easy on them now. Redline is about 5500 and 6000 is about the limit with the 50/1 mix. Over 6000 you need to mix 40/1 and hope it's a tight one. They fall off sharply over 7000. <br /><br />In theory the CAM-2 would allow a bit more advance (like back to the original 27) without pre-detonation - but I'm not gonna try it.<br /><br />If you melt it down, you know where to find me...<br /><br />-W