First Sterndrive, Lots of Questions

[79MERC1150]

Hi Everyone, We are longtime outboard people buying our first sterndrive. I have been reading everything that I can find about Mercruiser sterndrives, and have lots of questions. Our current boat has a 1979 Murcury 115 HP outboard. My parents bought the boat new, and I have owned it since 1994.

We boat only in freshwater, and our boat is a garage queen, which stays dry most of the time. Our engine has no signs of corrosion It was recently serviced with a new water pump, and the mechanic states that the engine looks new inside.

The new boat we want to buy is a 1990 Mach I Condor, 22 foot performance cuddy cabin, with a 454/ Bravo I. The boat is also a fresh water only garage queen, and shows no wear or corrosion. The OEM uppoulstery, hardware, and gelcoat all look like new. The hull is original and undamaged. The only signs of aging on the boat is some superficial crazing cracks around the screw holes where the windshield is mounted to the deck. The vinyl graphics on the sides have some superficial scratches on them, otherwise the boat presents like new.

It is a stock unit except for the though hull exhaust. Compression tests on the engine were 130 to 132 lbs on cylinders. On the water the boat runs very smooth, quietly, and has no issues, other then the operating temp never rises above 120F, which I believe is a faulty, or missing thermostate. The engine effortlessly pulls the boat along at about 40 MPH at 4400 RPM. It has a four blade power prop on it, and also comes with a three blade speed prop, that I have not tried yet. The engine is quiet, and there are no signs of rust or leakage anywhere on or under the engine. By all intents the boat presents like a time capsule. The current owner is a 64 year-old, who has used the boat for camping and towing the grandchildren on kneeboards and tubes. Since I am an old fart myself this fact makes me feel a little more secure, as I figure the boat has not been hotrodded to death:redface:.

Here are my concerns. I have been reading everything I can about Mercruser sterndrives, and am concerned about the statements made by several people stating that the exhaust manifolds and risers are only good for about four years. Does this four year projection mean salt water boats, boats that are stored in the water tied to a dock, or does this include trailered fresh water garage queens also?

Logic would seem the same as on my 79 outboard, that dry stored fresh water boats will last just like the outboard has, or do these parts fail frequently regardless of how they are used? Thanks in advance!
We will consider everyone's feedback before we make our final decision on buying the boat.

Betty & Charles Spray

 

[jtmarten]

Re: First Sterndrive, Lots of Questions

Beautiful Mach 1. I looked at a couple 28' Mach 1's before buying the Nova II.

I've not heard anything about a 4yr life expectancy for manifolds/risers. In salt water, maybe less than 4yrs if they're not flushed after each use.

120* running temp is really low, you're probably correct that someone removed the t-stat. Running too cold will cause increased internal engine wear.

 

[180shabah]

Re: First Sterndrive, Lots of Questions

yes the 4-5 year life expectance is for salt water use. Iron manifolds in fresh water only, could last forever. Still, you should pull then off and inspect internally.

120* is definitely low. Start be verifying the actual run temperature, gauge could be wrong. If 120 is accurate, first stop is t-stat and raw water impeller.

Couple other things to check, that you never had with an OB:
Bellows
gimble bearing and ujoints
engine alignment.

 

[79MERC1150]

Re: First Sterndrive, Lots of Questions

Beautiful Mach 1. I looked at a couple 28' Mach 1's before buying the Nova II.

I've not heard anything about a 4yr life expectancy for manifolds/risers. In salt water, maybe less than 4yrs if they're not flushed after each use.

120* running temp is really low, you're probably correct that someone removed the t-stat. Running too cold will cause increased internal engine wear.

Thanks for the information. I planned on pulling the manifolds off, inspecting the hard parts and replacing all of the gaskets and hoses. Knowing the condition of the parts will give me a baseline to go by.

Thanks for the compliment. I have heard of the Mach I brand being compaired as similiar to the Wellcraft. Your Wellcraft is one cool looking boat! I see why you choose it. Looks like you have it it pristine condition.

 

[79MERC1150]

Re: First Sterndrive, Lots of Questions

yes the 4-5 year life expectance is for salt water use. Iron manifolds in fresh water only, could last forever. Still, you should pull then off and inspect internally.

120* is definitely low. Start be verifying the actual run temperature, gauge could be wrong. If 120 is accurate, first stop is t-stat and raw water impeller.

Couple other things to check, that you never had with an OB:
Bellows
gimble bearing and ujoints
engine alignment.

Thanks for the information. The temp sending unit or the guage could be bad. I think that it is really running cold, as the engine is just warm to the touch. It sounds like a trip to the shop will be inorder. A couple of thousand invested in preventive maintenance will save even more expenses later. I can probably change the t-stat and pump myself, and R&R the manifolds, however the bellows, gimble bearing, and alignment sound beyond my mechanical skills, so I think that the boat should make a trip to the mechanic for a good going over.

 

[Mkos1980]

Re: First Sterndrive, Lots of Questions

My father is running stock manifolds and risers on on both his engines in his 1991 30ft Weekender. Fresh water though. When I bought my boat in 07 it had origional from 90 as well. No issues.

 

[jtmarten]

Re: First Sterndrive, Lots of Questions

Thanks for the information. I planned on pulling the manifolds off, inspecting the hard parts and replacing all of the gaskets and hoses. Knowing the condition of the parts will give me a baseline to go by.

Thanks for the compliment. I have heard of the Mach I brand being compaired as similiar to the Wellcraft. Your Wellcraft is one cool looking boat! I see why you choose it. Looks like you have it it pristine condition.

I saw a few online listed with Concorde as the mfg, and a few showed Concorde by Wellcraft. So maybe Welly aquired Concorde, or maybe just a division of Wellcraft?
Mine is close to pristine. One of the reasons I bought her. No bottom paint, completely stock, not molested or hacked up. I'm considering a switchable exhaust, but just don't think I can bring myself to cut holes in the transom for it.

I think its a very good idea to get yours in to have it checked out. At least you'll know what needs attention and what is good to go. The T-Stat and impeller are fairly easy to replace if you have a basic mechanical skillset, and its a good idea to replace them if you don't know when they were last replaced. Engine oil/filter and drive oil changes, as well as replacing the fuel filter/water separator. With just a little bit of maintenance you should have years of fun with her.

 

[79MERC1150]

Re: First Sterndrive, Lots of Questions

I saw a few online listed with Concorde as the mfg, and a few showed Concorde by Wellcraft. So maybe Welly aquired Concorde, or maybe just a division of Wellcraft?
Mine is close to pristine. One of the reasons I bought her. No bottom paint, completely stock, not molested or hacked up. I'm considering a switchable exhaust, but just don't think I can bring myself to cut holes in the transom for it.

I think its a very good idea to get yours in to have it checked out. At least you'll know what needs attention and what is good to go. The T-Stat and impeller are fairly easy to replace if you have a basic mechanical skillset, and its a good idea to replace them if you don't know when they were last replaced. Engine oil/filter and drive oil changes, as well as replacing the fuel filter/water separator. With just a little bit of maintenance you should have years of fun with her.

The information that I have is that BAHA Boats (not Baja Boats) bought the Mach I brand that was based in Florida about 1994. Concorde may have been the original owners of Mach I.

BAHA currently offers the Mach I name as their line of performance boats. There is not much information about Mach I, other then the boats seem to have a loyal group of fans. Wellcraft is obvoiusly a popular brand, where Mach I brand seems more obscure.

 

[79MERC1150]

Re: First Sterndrive, Lots of Questions

My father is running stock manifolds and risers on on both his engines in his 1991 30ft Weekender. Fresh water though. When I bought my boat in 07 it had origional from 90 as well. No issues.

Thanks for the information. It sounds like running these drive systems in salt water creates a whole different set of issues. That explains why the manifolds on the boat I am considering look as if they are the originals. They probably are.