3.4 V-6 275 Corsworths Info

[INXS]

I've got two of them that are in very good shape, fresh water use. One will go on my 24' Banana boat. I here you should only turn 5700-6000K rpms. OK then what if I put about a 18" setback, I think the new Banana's use 24" with a 250 E-Tech? I'm thinking 18" cause this motor weighs more? Anyway I'm thinking that at that set back the motor will work less hard, spin with less load?, and that it will allow me more, higher propping?, so that I'll get more speed with less stress on the motor?
Along with this is there any simple way to get more, aka reeds, compression, jetting? Also if I don't beat on it that often could I spin around 6300 rpms for say short one min spurts?

[Capt.Insane-o]

I would'nt spin them more than 5800, they are NOT an RPM motor and parts are very scarce these days. But do as you will.

[INXS]

I'm sure that's what I'll do. I paid 1850 for the two and If I get two yrs out of them I'll be happy. By then I'll probably have a modified 300 or a newer 350. I like to do this restore and repower at my own pace, I'm thinking 13K total and the boat. motor trailer should be all nearly as good as new, which in Banana $$$ equals 65K!

[INXS]

BTW, cool gun, I had an org., first yr production, mag 10!!!!

[Capt.Insane-o]

It's the having sex with a supermodel version of a shotgun.

I've been searching the bushes for a cleanish version of a 3.4. There are a half dozen I still service for guys, and when used as advertised they are a great motor.

[Dave S]

Have seen the insides of different year 3.4s and the later ones have the best parts. Big rod bolts, rubber reeds,Alluuummminum flywheel, and tappered wrist pins. If ya cleaned up the ports and cut the piston hole ya might get a bit more.;) I got one and I plan to make it a hand greanade.:thumbsup: Also put more crankcase bolts where needed.;)

[INXS]

It's the having sex with a supermodel version of a shotgun.

I've been searching the bushes for a cleanish version of a 3.4. There are a half dozen I still service for guys, and when used as advertised they are a great motor.

If you could e-mail or post the parts I need to get, to be ahead of possible problems I would appr. it!

I've heard that their's a plastic shift linkage that Merc still sells that may be needed. I've also heard that they no longer carry the water pump? The motors lok like they were hardly used so I'm thinking the starter, alt and other stuff should be OK, I hope.

[INXS]

Have seen the insides of different year 3.4s and the later ones have the best parts. Big rod bolts, rubber reeds,Alluuummminum flywheel, and tappered wrist pins. If ya cleaned up the ports and cut the piston hole ya might get a bit more.;) I got one and I plan to make it a hand greanade.:thumbsup: Also put more crankcase bolts where needed.;)

I may look into those things but I have heard that it's the main bareing that gives out on these motors???? If so I'm thinking that's why folks say to keep them under 5800 rpms?
If so I'll just use them for two or three yrs and shop around for a more powerful replacemnet, such as a 300XS or a modified, Wayne Taylor, OB. Lot's of options if you're patient.

[Capt.Insane-o]

The impeller is nla.. I should have two or three and I know where there is probably a dozen.

I'll look through Pro Marine and Sierra for what is still availiable. It's funny how Merc just totally abandons some engines. In the past few years they have lost a lot of customers around these parts due to NLA parts. BRP still offers parts for WAY back in the years, and these older motors are coming out of the wood work these days and are perfectly servicable units.

"If you can't get parts to service my motor why should I buy a new one and be in the same boat in a few years?"

Quote from a customer.

[Capt.Insane-o]

I may look into those things but I have heard that it's the main bareing that gives out on these motors???? If so I'm thinking that's why folks say to keep them under 5800 rpms?
If so I'll just use them for two or three yrs and shop around for a more powerful replacemnet, such as a 300XS or a modified, Wayne Taylor, OB. Lot's of options if you're patient.

They have a big rotating mass.

[mackeral5]

I would think sea-way has some of the obsolete 3.4 stuff, but I'm sure they want an arm and a leg for it...

[ChrisCarsonMarine]

Seaway has parts when i dont,we make good reeds for them,they are not high rpm motors,good work motors but heavy,the cosworths have updated top mains to solve the clogging problems common on the early 3.4's,[external oil line],all in all a good workhorse motor that mercury would like to imagine never happened,chris

[INXS]

I assume that to be on the safe side I should change the reeds?
Or with the prices I paid for the two motors, $1800, would it be best to just let them go as they are? I'm only thinking of using them, as I said, for two or so years. I've got no idea of the costs to change the reeds, maybe if I did it on the one I'll use and it costs only about $300 I'll go for it. I'm also thinking the new reeds would give the motor a better idle? Good thing it's winter and I'll have time to think this over. I still have to get the Banana painted!

[ChrisCarsonMarine]

Our reed set runs 220$,and will improve idle and midrange performance

[INXS]

Our reed set runs 220$,and will improve idle and midrange performance

Thanks, I'll check with my Mech. and I'll be in touch. BTW, are they rubber coatted and is there any jetting changes to be made?

[ChrisCarsonMarine]

The cages are rubber coated,no jet change necessary,chris

[Dave S]

You will need 12 cages and buy some reed gaskets .....you may need them.;)