1978 Merc V-1500 Black Max

[majestek12]

I have the opportunity to buy an 18' bass boat with a 1978 Merc. V-1500 Black Max.

The guy who I am buying it from is not the original owner and says that before he bought two years ago the prior owner had the engine rebuilt.

The guy I am buying it from said that he ran it for the last two years and that it performed wonderfully - "can't beat a mercury." He winterized it last year and when he tried to start it up this year it would crank but not catch. He said that he and a backyard boat mechanic-friend troubleshot the issue as the CDI. He said that the CDI module is a common failure point of the motor. The seller has already bought a pontoon boat and is looking to get the bass boat out of the driveway.

Reading more about it it seems that the CD ignition is fairly problematic but there are other parts of the ignition system that more commonly go bad - say the stator or rectifier.

The guy selling has offered to have his boat mechanic friend fix the CDI module so that I could see the boat run. My concern is that the CD may be masking some other issue - is this likely? I will of course do a pressure check on the motor before buying in case its a low compression issue.

What is the correct fuel/oil mixture? I have heard that with gas being 10% ethanol now-adays it is better to run a "different" mix - I am assuming a lesser-oil mix so as to keep the burn the same.

I am very new to "serious" boats (anything besides a boyhood john boat with 9.9 ob) and could use,a nd appreciate, any input whatsoever. I apologize if some of you may feel that I am wasting your time.

I know my way around car engines inside and out so I don't need a complete layman's breakdown. I know that there's a lot different between the two, but I am fairly well abreast of terms, parts, etc.

I am also wondering what "Black Max" is - I have tried to research the technology and all I can find regarding it are props that are specifically for the Black Max models.

Thanks!

 

[jimmbo]

Re: 1978 Merc V-1500 Black Max

Welcome to iboats

The gas/oil ratio is 50:1

"Black Max" was a name thought up by the marketing department. It was given to the V6 when it was first introduced. Now it is used to identify a line of props.

 

[BF]

Re: 1978 Merc V-1500 Black Max

I've had a V150 for a long time. I think mine is a 1980 that me and my BIL purchased in ~1988. We had the stator fail on ours once, but I don't think we've ever had CDI problems. IMHO, the main weak point on the motor is the driveshaft. We're on our 3rd. Sometime in the mid to late '80's they redesigned them with a beefier driveshaft. But... engine-wise it's been pretty bulletproof.

FYI there are a couple quirkie things about them (well mine anyway). It can take some finesse to start. Motor needs to be trimmed all the way down, if tilted up much (like on a trailer at a launch), it won't start. Once running, it can be trimmed up.

50:1 is the right mixture... but.... there is something about these motors that make them smokey... at 50:1 it'll make enough smoke at start up that your friends will ask how much oil you're mixing. It looks like you're running 20:1. There must be some place where fuel/oil puddles and burns off at start up. Don't worry about it... tell people it's a mosquito fogging feature. Other than startup, it doesn't smoke bad. Others may say using synthetic oil will make less smoke, but I'm too cheap for that.

If you can avoid ethanol gas, I would. Older carbs don't like it. No, I would not change the oil mix based on ethanol in the gas. Stay at 50:1.

good luck

 

[j_martin]

Re: 1978 Merc V-1500 Black Max

Replace the kill switch lanyard the racoons stole over the winter.

The thing I'd worry most about in a 1978 bass boat is the transom and rear floor.

hope it helps
John

 

[majestek12]

Re: 1978 Merc V-1500 Black Max

Jimmbo, BF, j_martin

Thanks for the warm welcome and your input. I really look forward to learning a lot from you guys.

From my first look at the boat, the condition is:

- boat
-- hull appears to be in good shape, no holes, cracks, patches, stress marks, etc
--floor is in good shape, no holes or soft spots, but does have one missing battery-compartment panel
-- new fuel tank/pump
-- working live well
-- working bilge pump
-- all electrical systems/lights functional
-- electric trolling motor with foot control
-- transom seems solid (no visible cracks, stress marks, repairs, etc.)

- motor (supposedly rebuilt <2 years ago)
-- 150 black max as described above
-- new stainless prop
-- guy says will fix ignition so i can see it runs
-- working trim controls

- trailer
-- not sure of make but is galvanized
-- single axle
-- may need new tires
-- hubs have bearing buddies
-- manual winch in good shape

All for $500 US - would you guys say its a good deal? I realize its a tough question without seeing the boat or motor, but an above average '78 as described above?

 

[BF]

Re: 1978 Merc V-1500 Black Max

prices are completely different in different locales. Up here, if he had it running, it'd probably fetch 3000-4500 as you describe it. A useable (not pretty) trailer alone is worth at least $500 in these parts. For comparison... a couple years ago I paid $500 for a 16' tinny, no motor, no trailer that was in such rough shape that I took it directly to a welder to get cracks fixed and patches put on. Last year I bought another 16' aluminum utility boat on a trailer (no motor) for $1100. The wooden seat tops were rotten and needed changing before it saw the water, trailer was OK, but no spare and had seen a lot of gravel. I still have both of these boats, and have had several friends tell me what a great deals I got on them.

So, it seems crazy cheap to me... You could sell the lower unit alone for $500. But don't worry, anything you save on purchase price, you'll more than make up by paying for fuel. My V150 can go through $100 of fuel eye-wateringly fast. But gas is pushing $1.50 per liter here, and it's on a ski boat mostly used for water sports.

 

[majestek12]

Re: 1978 Merc V-1500 Black Max

You guys are great with the quick responses.

I know what you mean, I keep asking myself if the deal is too good to be true. I am concerned about the motor but like you said, seems like I could at least get my money back on just the trailer if something big happened.

I know what you mean about the gas, my daily driver (hopefully soon to be tow-rig) is a full sized ford bronco with a 32 gallon gas tank... I was hoping the boat would be the better of the two on gas...

Thanks again for all the help guys.