I have this K/B 7.5 inboard with pipe had it for years never had fuel thru it.....somebody told me that these are no good that they grenade thoughts..

[DAVE MARSON]

 

[Wasted wages]

K/B = KaBoom !!

Best protection you can do is try to find someone that has a new RPM rod for sale... It's not a "bad" motor, but break a rod at WOT and bad things will happen.

Also a dot of blue lock tite on the case bolts is a good idea, K/B threads are pretty coarse threads
( unlike metric fine threads ) and have a bad habit of vibrating loose...

Also be careful of the head bolts...I would remove and keep them clean and lubed often...they are quite thin and are known to seize in place and snap off.. Don't lock tite the head bolts !!!

 

[FloridaScaleBoater]

Nothing wrong with the K&B 45 IB
Just use good quality fuel with at least 18% oil with some castor.
Ran them for years in Sport-40 & outriggers

 

[brad nichols]

If you compare it to other 45's it looks lite in construction and that could be the problem but they do run great and even better before they go KaBoom! Good fuel and oil will keep them happy but like all engines they wear out and bad things happen.

Brad

 

[Bill Gibson]

If they were junk i would not have offered you 100.00 for it on FB.........but if you dont run them just a tad rich and maintain them they will eat themselves up.......why do you think everyone calls them KABOOMS? LOL! And yes they are known for cracked lugs and cases!

 

[TJ Hammons]

If you compare it to other 45's it looks lite in construction and that could be the problem but they do run great and even better before they go KaBoom! Good fuel and oil will keep them happy but like all engines they wear out and bad things happen.

Brad

Sure seems like they all run their best right before they give up the ghost lol.

 

[DAVE MARSON]

If they were junk i would not have offered you 100.00 for it on FB.........but if you dont run them just a tad rich and maintain them they will eat themselves up.......why do you think everyone calls them KABOOMS? LOL! And yes they are known for cracked lugs and ca

If they were junk i would not have offered you 100.00 for it on FB.........but if you dont run them just a tad rich and maintain them they will eat themselves up.......why do you think everyone calls them KABOOMS? LOL! And yes they are known for cracked lugs and cases!

Bill......I have zero clue on nitro boat motors.....last time I ran nitro was 20 years ago in planes.........everybody assumes that everybody know all on thespages...YES I'm trying to get rid of it not because of what it is because I'm getting funds together for a gas boat........I don't have any online cash transfer so that makes it a bit harder to sell anything...TECHNICALLY I can't sell anything until I reach a giving amount of posts....sooooo

 

[Bill Gibson]

Bill......I have zero clue on nitro boat motors.....last time I ran nitro was 20 years ago in planes.........everybody assumes that everybody know all on thespages...YES I'm trying to get rid of it not because of what it is because I'm getting funds together for a gas boat........I don't have any online cash transfer so that makes it a bit harder to sell anything...TECHNICALLY I can't sell anything until I reach a giving amount of posts....sooooo

No problem Dave! You will get lots of good information on this site with any kind of power plant! Good luck with your endeavors, and have fun!!

 

[Rodney Rogers]

I ran the same engine with a RPM Rod in 1985 and 1986 in a Sightler deep vee I did very well 3 place in the Atlanta spring nationals .

 

[Alan Elzer]

If you want to race & be competitive get something newer otherwise install new bearings & go have fun

 

[Bill Gibson]

If you want to race & be competitive get something newer otherwise install new bearings & go have fun

Yes sir! Thats all I do with them! Just play around with them!

 

[Alan Elzer]

Great. Since just playing you don't need high nitro then. For fuel 25% is plenty 18% oil & have fun. Do you know how to change out the bearings for that engine?