What should I repower with??

[BPECK2500HD]

Tearing the motor and outdrive out of my boat....pretty sure main bearing is toast (exhaust gasket went and filled motor up.) thought i got it out quick enough but obviously not...so im taking it out so i can put something in that parts are available for and local boat shop will touch...

My question is what should I repower with?? id really like to use a 350 and a Mercruiser drive...does anyone know what Mercruiser outdrive matches the transom holes from the Yamaha??

and finally what am i getting myself into?? i understand its not gonna be direct swap- wham bam thank you maam...but what problems might the yamaha parts cause when switching over to merc?

 

[Gary H NC]

Re: Yamaha Sterndrive/ 4.3 for sale- What should I repower with??

Re: Yamaha Sterndrive/ 4.3 for sale- What should I repower with??

no Selling On The Forums!!

 

[BPECK2500HD]

Re: What should I repower with??

my fault i edited previous post

 

[HT32BSX115]

Re: What should I repower with??

Whew!!! Sure glad you got that corrected......


If it was a Cobra, SX, Merc, everything would just bolt right up.

You should probably go find yourself an inner transom plate to compare or get yourself a cutout template and see if it will directly fit.

A picture of the template is on pg 15 of the following manual. http://www.boatfix.com/merc/Install/gas/86419602.pdf

Someone here has probably done this and can tell you. If it doesn't fit or the hole is too big then you'll have to "fill the hole" and recut/drill it.


Cheers,


Rick

 

[BPECK2500HD]

Motor compatibility (Yamaha I/O to Merc motor?

Motor compatibility (Yamaha I/O to Merc motor?

Thank you for the info.

Ive read in a couple of different places of people with Mercruiser motors connected to other outdrives(only yamaha i saw was a 3.0merc with a yami leg but thats a GM too right?)

Does anyone know for sure if a merc 4.3 will bolt up to the yamaha bell housing? or better yet a 350?

Not too sure i can do any more than just swap out motor right now...i just looked at my bank account and compared it to the used stuff ive found

 

[BPECK2500HD]

Re: What should I repower with??

thank you for the info...i was just looking at some diff pics and was about to come to the same conclusion...what about tilt/trim & steering? i understand i will prolly need adapters... is there any other reason they wouldnt work?

 

[BPECK2500HD]

Re: What should I repower with??

ok so next option...would it be worth it to rebuild the 4.3 thats in it?

what happened:

Elbow gasket kicked the bucket...motor filled up with water...i immediately pulled the plugs and turned the motor over- popped water out of all the cylinders...checked the oil and it looked normal-NOT MILKY...went and got the new gaskets, got it all back together and ran it on the trailer with muffs- ran fine..revved up a little and sounded fine and dandy...put it in the water less than 24 hours later...ran fine for about 5 min...was cranking approx 3200 RPM and was trying to advance to about 3500 when the motor started squealing LOUD..backed off it and it slowly started knocking along with the squeaking...limped it back to the dock and shut it down...wouldnt start back up but turned freely...let me kno what ya think...

 

[mylesm260]

Re: What should I repower with??

You're block is NOT worth rebuilding, because you need to do a lot to you're motor to get it back up to snuff. You've likely damaged you're mains, which means line-bore which writes you're engine off right away.

If I were you, I would pull you're engine, and remove everything from it. The ignition, the starter, the alternator, the water pump, the frost plugs, everything.

Then get yourself a 4.3 vortec (google gm vortec engine wiki) from a running truck (call you're local wreckers) 1996-2001 seems to be the sweet spot for cams.

You will NOT have to change the truck cam, but you will have to change the truck head gaskets over to marine (unless you're engine is closed cooling, in which case, you could rock the truck gaskets)


I paid 250 bucks from a u-pull wrecker for my running 4.3.

After you get you're truck motor, you can rebuild it, if you like. Try to figure out the milage on the engine before you get it.

Rough rough outa my *** numbers

The 4.3 in a truck should go to about 120-150,000 miles. The 4.3 in a boat should do about 1000 hours. If you're doner motor has 60,000 miles on it, than consider it to have 500 boat hours.

It is much easier and less expensive to rebuild a running engine than it is to rebuild one that has already had a catastrophic failure.

4.3's are a dime a dozen, I would take all you're marine parts off it, and throw it away, Not worth you're time and money to try and rebuild it.

 

[wca_tim]

Re: What should I repower with??

You could also buy a reman longblock for around 1500 and have a warranty.... or even a new one for not a ton more.

 

[BPECK2500HD]

Re: What should I repower with??

Will the bolt patterns be the same in the truck motor?

The more i think about it, the less sense it would make for the pattern to be different on just a yamaha..seems like they would have to pay alot more money to get a special GM block...i will look into the truck motor thank you for the info Myles.

Tim- That is probably my best option, but i just dropped 3 Grand to pay for the Police Academy, so that might be a winter project


Thank you both.

 

[BPECK2500HD]

Re: What should I repower with??

So I found a couple 4.3 motors...some decent priced, some not... about 200 from a u pull shop and right around a grand from a parts warehouse. A 350 was almost exactly the same price, give or take a hundred...I really am leaning towards getting a v-8 as the 4.3 had its work cut out, and i do alot of tubing/skiing.

Ive think im going to take the yamaha leg off. i found some good prices on complete alpha drives.

What do you recommend for a merc outdrive? looking for reliability and availability of parts.

 

[jaxnjil]

Re: What should I repower with??

are you sure all you have to change is the leg? sei is as cheap as you can get and they come new with 3 year no fault warenty.

i dont know any thing about yamaha drives but would be surprised to find out they use the same transom assambly as mercuriser and a alpha will bolt right up to one

 

[Bondo]

Re: What should I repower with??

ve think im going to take the yamaha leg off. i found some good prices on complete alpha drives.

Ayuh,... It appears you Don't Understand,...
You'll have to Remove, EVERYTHING that's Yamaha from your hull,...
And Replace it with Mercruiser stuff....

The Best, Quickest, Cheapest way to accolimpish that is to buy a Donor boat with the Driveline you Want,...
Junk it,+ Install EVERYTHING in Your hull....

 

[BPECK2500HD]

Re: What should I repower with??

i should have elaborated...i meant changing the whole deal...found a couple complete assemblies from donor boats...im done boating for the season, so im lookin to take baby steps... my financial situation says take baby steps also...ive found a few boats with complete setups with rotted floors/ hull damage/ trees fallen on them etc. i just want to get the most info possible before i tear everything out then end up with a big hole and nothing to fit in it.


Think insurance company will notice if it didnt run when it sank?

 

[Bondo]

Re: What should I repower with??

ive found a few boats with complete setups with rotted floors/ hull damage/ trees fallen on them etc.

Ayuh,.... Mid to late 80s to 91 will get you the Alpha 1 drives with whatever motors,...

Around 91/ 92 is when the Alpha Gen.IIs came out....

The Big difference is,... Any outdrive from Alpha 1 back will bolt to the Alpha 1 transom assembley....
Gen.IIs only fit themselves....

Not that it matters,... Both are Good Choices,+ are relatively Cheap....

 

[BPECK2500HD]

Re: What should I repower with??

Thank you for that info.


Back to the other question....if i left the yamaha stuff and just changed motors, it should bolt up, correct?

The yamaha stuff isnt a problem...it hasnt caused any problems for me..yet

this boat isnt anything special, and by the looks its gonna be a lil too expensive to change it all over...i just wanna hit the water...disregard my previous posts, Ive made up my mind to just change out engines, as long as a truck motor will bolt up to that yamaha bell housing, which i cant tell if is different.

I apologize for being a noob..this is my first boat, first sterndrive..just want to get as much info as possible, since my local shop laughs when i come in to ask questions bout yamaha sterndrives...thank you for the input

 

[jaxnjil]

Re: What should I repower with??

they are readily available for the alpha drives and you can get them right here on i-boats. i have heard all good and no complaints.
i don't think they make a yamaha replacement drive if thats what your asking

i think you will need all the stuff in this picture plus a trim hydraulic pump, top shifter and cable, and steering cable to fit the alpha. this is assuming your yamaha pump, shifting system, and steering are different form mercuriser.

i am swapping my alpha for a bravo3 and it was very easy for me because all the stuff in pic is alpha and the bravo stuff i needed to change are direct bolt in changes. the transom assembly in pic is alpha its just been painted white

 

[gadget73]

Re: What should I repower with??

This may be a silly question, but is there any reason he couldn't simply bolt the 350 in place where the 4.3 was? The bellhouse is the same as far as I know. Is the Yammie drive just not strong enough to handle a 350? I know nothing about their drives, never even seen one to tell you the truth. Manifolds and such would obviously be different, but thats usually not anything too hard to overcome.

 

[BPECK2500HD]

Re: What should I repower with??

that is what i would like to do, but i think the gearing is different between the 4.3 drive and the 350 drive....can anyone confirm this?

im heading back to georgia in a week from NY, i think i might have to go give Captain Ken a visit and be enlightened.

 

[jaxnjil]

Re: What should I repower with??

have no idea what the 4.3 runs for sure but the 350 will take a 1.50 to 1
i got the idea some where you had trashed your Yamaha drive to.
if its OK and your short on cash keeping it and doing a 4.3 might still be the best way to go. get it running and sell it and get what you want later