Printable View
Boat motors live a HARD life, that's why boat motors get all the best parts. Be carefull where you scrimp on parts. I had a jet boat with a 455 olds, and I would have to spin it to 4000 RPMs to back it away from the dock. Those motors have to be able to live at redline for sustained cruising while enduring a full torque load, and flashes of RPM when the prop unloads on waves. Good luck, I would build the best motor I can for my piece of mind.
Thanks,
I would agree with building the best you can in most cases (Especially a jetdrive), with a $300 125k 350 I know I'm rolling the dice. But with my job future uncertin (I'm blue collar / factory / production) this one is gonna be a bare bones Economic Crisis bottom dwellers motor. Our core business has dropped 50%+ this year, they cut 500 jobs last Friday, more cuts will be made if things do not pick up soon. http://www.nbc12.com/Global/story.asp?S=10321265
The competitoin ski boat (think Master Craft) is often called a ski tractor, it cuts the water, and the prop should never be air borne. If the water is that ruff then we are not skiing. This is not a pleasure boat and not a go fast boat. All will happen with in a 5 miles stretch of the river in the narrow upper most navigable section. Here I can make a call or walk home if necessary, most of the river is shallow. We will not be traveling far ~ just skiing and pulling the kids around, just enough to get out and play. I doubt we run much over 10 hrs per year.
your not going to see any hp parts or top shelf part in low hp inboad boat engine s less it past 300hp the older 350 were cast pistons cast cranks nothing much dif then you would see in a chevy truck they had a marine cam s . iron hi rise intakes oil pans and wind trays brass block plugs .that about it . but when i check in used boats if it had a car engine in a used boat that cut the resale in 1/2
I got the new cam bearings installed in my block with the crank rods pistons in place. The owner of a top area machine shop actually came outside in 95 deg heat and installed them while the engine was on the stand on my car trailer. WOW!!!! He didn't want my dirty engine in his clean shop. He checked them with one of his cams and made slight adjustments to #2 & #5 with a 3m flap strip on a rotory tool. He charged $50 + bearings = $80... I tipped him + $20 for the drive thru service. I was greatfull as (2) other shops turned me down saying they were not interested.
He also gave me an education about the new style hardened aluminium bearings, as my old ones were the grey / brass (grey was slightly worn thru on the drive side 4/5/6 o-clock).
Now I need spend some time with my family ~ to earn more shop time... So It might be a while before I can get back to wrenching.
well here is how i see it ...i done them in the block with crank in .that job is not on top of my list but is ez on the sbc for the 360 groove bore . as for your old cam bearings well they do have 125k on them .every one that has put cam bearing has some tune up tools:D .there is some cam bearing prep that i do that helps about better 90% of the need for the tune up tools . as for the hard alum cam bearings i use the durabonds they are a lead babbitt bearings they will take deflection and anti-seizure when loaded on engines and emdebability it can be a big deal. when your running big springs on the heads like a 455 buick you can push the babbitt. i never done it but it a oil deal as well .i never have seen a durabond do it on a bbc or mild sbc . not a big deal on bbc i used the stock ch12 in roller engines with very hi lbs springs for years .i have never had any thing go south to were i would move up to a harder babbit. it is more of a builder choice i used both . i do care what ones i use in a stock build . were i do care is i like a tube shell and not a rolled shell backer some guys think the lead babbitt is to soft it takes time to put them in they nick ez so a hi speed shop may like the harder babbitt alum bearing s .you do not have to be so ez with them but the harder the babbitt is it can grab the cam and have seizure:eek: were the lead will move some the cam should run on oil:HMMM: if the bearing get in the way i would like the bearing to move .there not much give on a hard babbitt bearing if they can not move they can over heat start to come apart and very bad things happen .but on your build you will never see it all out race engines you can and at that point you bore your block out for bbc cam bore or go roller bearings
Cool stuff ~ Thanks!
Now i've got to find a trick for the odd angle intake bolts...
(Made a new post on this one.)
Just took out 16 stuck lifters by catching them with vice grips, raising them until you can see the groove, leave them stuck there, get some Seafoam deep creep, shoot the lifter nice nice then rotate, deepcreep gets rid of the varnish built up on the lifters with a twisting motion in seconds. worked fantastic.
Engine cleaned and painted, Lifters swapped, and valves adjusted.
The original boat motor looked like it had only 200 hrs on it (inside). Everything looks brand new. Previous owner had installed a set of crane roller rockers on it (bonus). Too bad they were on the junk 1980's low flow emission heads that crack when you sneeze.
Set the valves using tech inspector's tip ~ zero lash + 1/2 -3/4 turn. Counter rotation motor makes it a little more confusing (crank spins backwards / cam spins forwards) but as long as you use the backwards firing order things work out the same.
Just need to finish modifying the early gen 1 intake for the late gen 1 heads and button up the small stuff. Should have the boat ready to go by winter...