Time to upgrade. Looking at 5.0 MPI w Bravo 3

[Pruno]

Good evening - After a few years of boating we decided it’s time to upgrade into something a little newer and bigger. I’m familiar with the carbed 4.3 and Alpha Gen 1. The boat I’m eyeing has 5.0 mpi and Bravo 3. I’m trying to do as much research as possible as I’m not familiar with either.
Anyway, I figured I’d do a compression test as long as the current owner will allow it. I know I want all the plugs out and no fuel or spark. I came across some internet info that says as long as the key is off I can jumper the start solenoid to spin the motor with no fuel or spark. Is this true, best and/or easiest way? Any other gotchas to know about this motor?
Owner states that he hit a rock and it took out the forward gear and that reverse still works normal. If it is just the forward gear do all of the metal shaving just migrate into the lower and take that out too? Is it possible and recommended to only replace the forward gear? Seems like a complete rebuild isn’t cheap by any means and probably not worth the investment in time, tools and parts? I think going into the deal I have to assume the whole drive needs to be replaced, but is there anything I can look for or test without being too intrusive to help determine the extent of damage and repairs needed?

-Pruno

 

[Scott06]

Good evening - After a few years of boating we decided it’s time to upgrade into something a little newer and bigger. I’m familiar with the carbed 4.3 and Alpha Gen 1. The boat I’m eyeing has 5.0 mpi and Bravo 3. I’m trying to do as much research as possible as I’m not familiar with either.
Anyway, I figured I’d do a compression test as long as the current owner will allow it. I know I want all the plugs out and no fuel or spark. I came across some internet info that says as long as the key is off I can jumper the start solenoid to spin the motor with no fuel or spark. Is this true, best and/or easiest way? Any other gotchas to know about this motor?
Owner states that he hit a rock and it took out the forward gear and that reverse still works normal. If it is just the forward gear do all of the metal shaving just migrate into the lower and take that out too? Is it possible and recommended to only replace the forward gear? Seems like a complete rebuild isn’t cheap by any means and probably not worth the investment in time, tools and parts? I think going into the deal I have to assume the whole drive needs to be replaced, but is there anything I can look for or test without being too intrusive to help determine the extent of damage and repairs needed?

-Pruno

First read up on bravo corrosion issues. very common on B3 drives for corrosion to require gear case replacement.
If he hit a rock it such that it no longer has forward gear likely you are looking at a complete tear down and inspection.
yes you can do a compression test that way but really engine needs to be up to temp. So get it warm, ground hi volt wire off coil so you can spin the engine with out plugs in to do the comp test.

boat needs to be priced such that you can buy a replacement drive and the deal still makes financial sense. If it were a simple or cheap repair the seller would have done it …

 

[alldodge]

Owner states that he hit a rock and it took out the forward gear and that reverse still works normal.

Bravo's don't work that way, if FWD is out so is REV.

Damaged boats are always cheaper, but without a test run on the water there is so many things that can be missed/hidden. The drive will need to be replaced and don't buy it if you don't see it run.

 

[QBhoy]

Sounds like an expensive gamble.
But if you’re keen and do still want to compression test her. You’ll find that if you pull the lanyard safety kill switch, you’ll be able to crank the engine over without fuel or ignition. Hope that helps.

 

[tpenfield]

Wait a minute . . .

You want to upgrade your boat and are considering a boat that hit a rock, the outdrive is damaged, and you are concerned about doing a compression test on the engine?

Don't waste your time. I would suspect for the time and money that it would take to put it all back in working order, you could buy something that is fully operational.

Unless you are looking for a project and getting the boat for next to nothing. As AD mentioned the Bravo outdrives shift differently.
It happens in the upper unit with a cone clutch, as opposed to the Alpha drives that shift in the lower unit with a dog clutch.

 

[Pruno]

Thanks for the input all. I understand that purchasing a boat with damage is a gamble, but looking doesn’t cost anything but a little time. Nothing ventured nothing gained.

I just assumed that it stripped the teeth from FWD and maintained enough on the teeth input shaft to still catch rev, but I don’t not S about it - hence why I came here looking for answers. I’ll keep digging to see if I can get a better understanding how it works. Regardless, I’ll consider the outdrive toast.

The bit about the compression test and the outdrive were two separate questions. If it gets to the point where I might make an offer I think I might want a compression test and I don’t want to blow myself up. “Only you can prevent boat fires…” or something like that. I haven’t seen the boat in person yet, I assumed that just the prop hit a rock not the hull itself, but I dunno yet.

 

[ejnichol]

5.0 with a bravo 3 is two prop unit I thought. The performance may be underwhelming. Usually see that with a 5.7 or 6.0 or larger motor.

 

[Pruno]

5.0 with a bravo 3 is two prop unit I thought. The performance may be underwhelming. Usually see that with a 5.7 or 6.0 or larger motor.

It does have 2 props

 

[ejnichol]

It does have 2 props

It may not be a issue. Many advantages to dual prop but you do lose some speed on top end vs single prop outdrive.

 

[Buster53]

My best suggestion…walk away from this boat and do not look back.