470 swap to 4.3

[Winterd03]

I was advised by others to join this thread as there have been lots of information of swapping a 190 to a 4.3. Based on discussion I’ve heard it can be fairly straight forward as it should pair with the outdrive and the stringers on my ‘85 Chris craft scorpion 215 “should” along to hold the v6. The hull/boat is in great shape and I think it is an opportunity to put in a little more power. Looking for advise/tips/ links to prior conversations regarding this topic - thanks in advance. I will also be interested in where to locate a remanufactured engine and a mechanic in the Midwest that would consider this project. Cheers

 

[dubs283]

Is there a problem with the 470?

You can always get home with the kicker

Cool boat, btw

 

[Dubed]

Glad you took my advice and joined D.
These guys are great and will certainly help you with all the info needed to make your decision. I decided to rebuild the old 190 but you may make a different decision.
Good luck

 

[Winterd03]

Thanks for the welcome - yes the 470 (190) is blown. The mechanic I am working with is actually advising to scrap the boat but it is very hard for me to do. I’d be willing to put money into it especially if there is an opportunity to put in a somewhat newer motor/refurbished into it with more power… it has potential to be my dream boat when done. However I am no mechanic and everyone seems to have different advise so it’s been hard to follow. Thanks in advance!!!!!!!

 

[Scott06]

What is the condition of transom and stringers given age of boat there is significant risk for strucutral rot. Not that these cant be fixed just would likely push he cost to the point where it likely wont make $ense.

michigan motorz sells new and reman engines, probably could do the swap for you.

 

[Winterd03]

What is the condition of transom and stringers given age of boat there is significant risk for strucutral rot. Not that these cant be fixed just would likely push he cost to the point where it likely wont make $ense.

michigan motorz sells new and reman engines, probably could do the swap for you.

The transom was repaired the previous owners. I suppose I will have to take a closer look at this but I believe the stringers are good. What is the best way to confirm this on a fiberglass boat

 

[Scott Danforth]

Hey... @nola mike

 

[Scott Danforth]

The transom was repaired the previous owners. I suppose I will have to take a closer look at this but I believe the stringers are good. What is the best way to confirm this on a fiberglass boat

Core test drills is the only way to verify rot or no rot

I would look for a 1996 and later bobtail

 

[ROY WILLIAMS]

Thanks for the welcome - yes the 470 (190) is blown. The mechanic I am working with is actually advising to scrap the boat but it is very hard for me to do. I’d be willing to put money into it especially if there is an opportunity to put in a somewhat newer motor/refurbished into it with more power… it has potential to be my dream boat when done. However I am no mechanic and everyone seems to have different advise so it’s been hard to follow. Thanks in advance!!!!!!!

my 1978 MCM470 a carb 2barrel 170HP.. I bought it in 1986 ...I winterized it now .... the engine oil is 15-40 wt ... I put sn plus 4OZ in the oil ... and I used 93 octane gasoline with the marvel mystery oil 2 oz in 10 gallons ... the engine runs great . no damage , also the flat tappets have no noise ..
did you over heat the 470 engine ? also the timing is around 4 degree ..
the new engine oil is lower zinc ..... the valves, damaging ,then reduce your timing ....

 

[Eric 3.7LX Alpha 1]

Thanks for the welcome - yes the 470 (190) is blown. The mechanic I am working with is actually advising to scrap the boat but it is very hard for me to do. I’d be willing to put money into it especially if there is an opportunity to put in a somewhat newer motor/refurbished into it with more power… it has potential to be my dream boat when done. However I am no mechanic and everyone seems to have different advise so it’s been hard to follow. Thanks in advance!!!!!!!

Blown as in a rod is sticking out the side of the block? Or a blown head gasket?

 

[Winterd03]

Cylinder seized

 

[Scott06]

Cylinder seized

Here is a 205 hp 4.3 https://www.ebay.com/itm/2347677813...Bl7QiqNuMLNmfYV8skb139PBYf|tkp:Bk9SR4TTjr2KYQ

would need some odds and ends like a wye pipe but should bolt up to your outdrive

 

[Winterd03]

Here is a 205 hp 4.3 https://www.ebay.com/itm/234767781338?hash=item36a9400dda:g:JMAAAOSwx~RjZtiO&amdata=enc:AQAHAAAAsE+Hpnwg271OphGEsONEBZGNN/gBO+YpVRk3bmDkd8/8HMoRqfThQRp59ikPlcR4HhEORjlRVEgnAEhcCAeLsf3FSKiF3Erk5EWwrfGE+QrS7lT27eQw4XlJ9vr+/3rzT9xpBy/7d0BMq04vKhb2HJMNBZx9wJAyS/dQtfACtDYGKMt8q57CYGBx0QN7TK07h+wNX1RwT6DYGPdNDyBl7QiqNuMLNmfYV8skb139PBYf|tkp:Bk9SR4TTjr2KYQ

would need some odds and ends like a wye pipe but should bolt up to your outdrive

 

[Winterd03]

I did see this - is this one that you are selling? Curious what shipping would be to wisconsin

 

[Scott Danforth]

I did see this - is this one that you are selling? Curious what shipping would be to wisconsin

Check with green bay propeller. The have a boat salvage yard

Scott just posted a 4.3 that he found

 

[Winterd03]

Check with green bay propeller. The have a boat salvage yard

Scott just posted a 4.3 that he found

I called Green Bay prop regarding a 305 I saw they had listed online… no 4.3’s…. I’m not sure if that would even be an option but would be nice to have the hp. Are you from wi? Any recommendations on mechanics I could reach out to for this kind of work? As mentioned a few I spoke to we’re not to thrilled about it….

 

[Scott06]

I did see this - is this one that you are selling? Curious what shipping would be to wisconsin

No I am not selling, just one I saw. Would figure $300-400 shipping depending on where you are in WI.

I called Green Bay prop regarding a 305 I saw they had listed online… no 4.3’s…. I’m not sure if that would even be an option but would be nice to have the hp. Are you from wi? Any recommendations on mechanics I could reach out to for this kind of work? As mentioned a few I spoke to we’re not to thrilled about it….

Would second green bay prop, not sure of they would do the work too?

If you have the room in engine bay given size of boat a 5.0 or 5.7 would be a good power increase.

 

[Winterd03]

No I am not selling, just one I saw. Would figure $300-400 shipping depending on where you are in WI.


Would second green bay prop, not sure of they would do the work too?

If you have the room in engine bay given size of boat a 5.0 or 5.7 would be a good power increase.

Would the 305 use the same outdrive, wiring, and transom bracket? Anything else I would need to consider? It sounds like I just need to find a mechanic who has worked on more engine swaps…. I certainly don’t know but I am lead to believe it is more work/money than it’s worth…. Yet I was given a quote to do it. Hard to make that call.

 

[ROY WILLIAMS]

Cylinder seized

the engine is the wrong timing ... cylinders pistons are like a fire piston then it is seized ... hot !!!

 

[Scott06]

Would the 305 use the same outdrive, wiring, and transom bracket? Anything else I would need to consider? It sounds like I just need to find a mechanic who has worked on more engine swaps…. I certainly don’t know but I am lead to believe it is more work/money than it’s worth…. Yet I was given a quote to do it. Hard to make that call.

Outdrive, yes but you would need to go up in prop pitch. I did a 4.3 to 50 swap, went from 19” to 21” pitch
wiring, you need the correct harness for your engine but it will plug into your boats harness and work fine.
Transom housing yes, but you need the exhaust wye pipe for a V engine.
likely be more $ to repower than the boat is worth. What was the quote $ ? The boat i have the PO cracked the block, he tapped out when he was given a $10-11 k quote to install a merc reman bob tail. That was seven years ago…
it made sense to me because doing the work my self i was in it for a out $5-7k less than a comparable working boat. If you are paying someone to do all the work you may spend more than getting a new to you boat.
would define verify the stringers and transom are solid by drilling test holes. As long as someone did a decent job replacing them…