Looking to re-power my 342. Who and what would you go with?
Wildboating
Member Posts: 957 ✭✭✭
As the title says, I am thinking it is time to repower my 350 Mag Mpi engines that currently have 500 hours on them. This was not on my todo list but Last year i had to rebuild the heads due to tuliped valves at the tune of nearly 7k and now i find myself with problems again.
As many of you have, i have been counting down the days to launch the boat which came for me yesterday. Unfortunately for me, within 10 minutes on the water i knew something wasn't right. We put new props over the winter because the boat wouldn't turn over 4000 rpm previously. We went from 24p 3 blade to 20p 4 blade at the suggestion of hill marine after walking through the characteristics of my motors and our end goal results. After a nice warm up cruise i started to throttle up and found the boat would list to the port side heavily. I worked with the trim tabs to level the boat out and cruised up to 4500 rpm at which point i noticed the starboard motor peg the oil pressure. I promptly returned to idle and lifted the hatch to a knock sound in the motor on the starboard side. I shut it down and limped to my dock on one engine. My mechanic came down and fired the motor which knocked for a few seconds then cleared up at idle. If you rev the engine up to about 1600 rpm the bottom of the motor starts to chatter horribly which left him and another mechanic with the same consensus that I had spun a rod bearing. I am being told that i will cost about 3k or more to tear the motor down, replace or repair to get us back up which now puts me at 10k in motor repairs and still left with 500 hour motors and who knows how long the other will last.
So back to my original statement, I'm thinking it makes better sense to replace my 350 mag mpi motors with new 6.2 stroker long block motors which will give a nice 140 total horsepower boost and a nice amount of torque. If you were in these shoes would you keep repairing or just replace and be down with it? I should be able to sell my one good engine off and the other for repair and get a few grand out of them which will help bring the cost down. Im thinking i can do the complete swap and repower from the 350's to 6.2 for about 10g after selling my engines off. Would you do the same, any companies you suggest for picking up the 6.2 long blocks?
As many of you have, i have been counting down the days to launch the boat which came for me yesterday. Unfortunately for me, within 10 minutes on the water i knew something wasn't right. We put new props over the winter because the boat wouldn't turn over 4000 rpm previously. We went from 24p 3 blade to 20p 4 blade at the suggestion of hill marine after walking through the characteristics of my motors and our end goal results. After a nice warm up cruise i started to throttle up and found the boat would list to the port side heavily. I worked with the trim tabs to level the boat out and cruised up to 4500 rpm at which point i noticed the starboard motor peg the oil pressure. I promptly returned to idle and lifted the hatch to a knock sound in the motor on the starboard side. I shut it down and limped to my dock on one engine. My mechanic came down and fired the motor which knocked for a few seconds then cleared up at idle. If you rev the engine up to about 1600 rpm the bottom of the motor starts to chatter horribly which left him and another mechanic with the same consensus that I had spun a rod bearing. I am being told that i will cost about 3k or more to tear the motor down, replace or repair to get us back up which now puts me at 10k in motor repairs and still left with 500 hour motors and who knows how long the other will last.
So back to my original statement, I'm thinking it makes better sense to replace my 350 mag mpi motors with new 6.2 stroker long block motors which will give a nice 140 total horsepower boost and a nice amount of torque. If you were in these shoes would you keep repairing or just replace and be down with it? I should be able to sell my one good engine off and the other for repair and get a few grand out of them which will help bring the cost down. Im thinking i can do the complete swap and repower from the 350's to 6.2 for about 10g after selling my engines off. Would you do the same, any companies you suggest for picking up the 6.2 long blocks?
2003 Rinker 342 Fiesta Vee, 350 Mag MPI, Bravo 3 2.20:1 w/ 22p 4 x4 props
Comments
The 350 MAG MPI when propped correctly should be fine. That is my set up.
PC BYC, Holland, MI
more hp and $$$$ equal to maybe a few mph gain. Added stress to the boat and drives. Also would mean another set of props. Torque would help with hole shot and plane speed but that's about it.
unless your rpm Gages are off there is a possibility you reeved to high but most boats will hit the rev limit and let you know.
So I don't think that's it. I would stick either with reman power plants you have now or look up to see what your year offered for power. Also look what drive and gear came with bigger motors.
Go Steelers!!!
My '03 with the 350/B3 package would cruise all day at 30-32 mph, and top out above 40. I once got it on plane with 12 people aboard. If your boat wasn't doing that, don't blame the engine size ... something was wrong with your engines, your props or both!
You could also look at remanufactured small blocks from Mercury as well.
u like to smell like diesel
it smells good
Al has noted on here before to run 22P with the 350 MAG MPI.
If you were only getting 4,000rpm WOT, that sounds like an engine issue. 1" of pitch = 200 rpm change, you would have to drop from a 24P to an 18P to get the rpm to ~5,200 WOT. No way, that is too small a pitch.
The 6.2l takes up more room as it is closed cooled too. Be big $ to swap with all the correct MPI stuff too. If your 342 is an '03 or earlier, no room for anything but the 350 or 6.2l anyways. 2004+ has a bigger engine room.
PC BYC, Holland, MI
over heat, or water intrusion. Engine Tare down will tell the story.
PC BYC, Holland, MI