Please help me. Need some advice.

[Manny503]

I recently bought a 1990 Monterey 19footer. And its been hard finding info on this boat. Im new at boating. So my boat comes with the 4.3 L Chevy V6 motor and a 260 mercruiser sterndrive. I recently changed the motor oil and someone recomended me to use 20W 50. So i did. But i wanna make sure thAtll be fine before i take the boat out for the first time. I dont want to use the wrong oil and burn the motor. and so i also changed the oil for the sterndrive 260 mercruiser. I went to west marine and they recommend me to use a high viscosity oil so i got 80w 90 for it. Please help me. And tell me if im ok to go . I dont mind changing it again if im using the wrong oil. Thank you very much in advance for all your help. I appreciate it. Im a rookie at this.

 

[bspeth]

Re: Please help me. Need some advice.

Get the proper factory manual,and it will tell all.I think theres a link in the adults only section at the top of this forum,a ton of great info in there as well.welcome to Iboats.

 

[Manny503]

Re: Please help me. Need some advice.

Get the proper factory manual,and it will tell all.I think theres a link in the adults only section at the top of this forum,a ton of great info in there as well.welcome to Iboats.

Thank you i found it i will check that out. Thank you very much.

 

[achris]

Re: Please help me. Need some advice.

The engine oil you should use will depend on the area (temperature) you're in. The only drive oil I can recommend is Merc's own High Performance Gear Lube.

I will make some observations. 1990 would make it an Alpha One model drive, a '260' label on it would make it a)earlier, and b) a 1.50:1 ratio. The 1990 4.3 was delivered with a 1.84:1 drive. To help us help you, post up the engine, transom assembly and drive serial numbers. If you're not sure where to find those numbers, or what they should look like -> http://forums.iboats.com/non-repair...engine-serial-numbers-630103.html#post4398812

Chris.....

 

[Manny503]

Re: Please help me. Need some advice.

The engine oil you should use will depend on the area (temperature) you're in. The only drive oil I can recommend is Merc's own High Performance Gear Lube.

I will make some observations. 1990 would make it an Alpha One model drive, a '260' label on it would make it a)earlier, and b) a 1.50:1 ratio. The 1990 4.3 was delivered with a 1.84:1 drive. To help us help you, post up the engine, transom assembly and drive serial numbers. If you're not sure where to find those numbers, or what they should look like -> http://forums.iboats.com/non-repair...engine-serial-numbers-630103.html#post4398812

Chris.....

Im in Los Angeles, Ca. I will look that up and post it as soon as i get a chance. Thank you very much. I appreciate it.

 

[thumpar]

Re: Please help me. Need some advice.

The 260 is for the HP rating of a 5.7l engine. Looks like the drive was swapped out and your ratio is wrong. I use the Quicksilver (Mercury brand) drive lube. I can find it at the local Walmart here. I wouldn't take advice from West Marine. The only time I go there is when I know what I want and they have it when I need it.

 

[Manny503]

Re: Please help me. Need some advice.

thank you ok so this is what i have for the transom assembly serial no. 0D330243
this are the other two: mercruser serial no. on left side: 5400580
right side numbers are: 1.50 R

thats all i got as far as serial numbers. hope you can help me with this ones. thank you again. i really want to know what i have in hand.

 

[thumpar]

Re: Please help me. Need some advice.

With that ratio I don't think you will be able to reach WOT with the 4.3l. Even if you proped down it will probably not be enough. If you run it and it is not able to get to WOT you are lugging the motor. Let us know the WOT that you can get to. My guess would be you can't get the correct WOT and at that point you either need a different upper/complete drive or to get a bigger motor.

 

[Manny503]

Re: Please help me. Need some advice.

omg.... this is more complicated than i thought (((((( so but what do you think about the oil i used for the lower unit?? i used west marine 80W 90 and for the motor i used a 20W50 motor oil. the motor has 429 hours total. is what i used ok??

 

[thumpar]

Re: Please help me. Need some advice.

As long as you filled the outdrive from the bottom up you will be fine if it got full. The engine will be fine with that oil. It is more important to have oil/lube than anything. There may be better products but what you have is WAY better than not having anything.

 

[Manny503]

Re: Please help me. Need some advice.

yea i filled up from the bottom. until oil came out top. and ok, ll give it a try tomorrow. and ill let you know how it went. thanks. i appreciate your help. first time taking it out on the ocean. but im bringing ppl that do it constantly.

 

[tazrig]

Re: Please help me. Need some advice.

Did you remember to replace the washers from both the drain and fill screws? You replace them each time you change the oil. It helps prevent getting any water in the drive.

 

[achris]

Re: Please help me. Need some advice.

By the serial numbers, the transom assembly is 1990, but the drive is about 10 years earlier, and the wrong ratio for that engine. If the boat is very light you'll probably be ok with a very small pitch prop. The way to check is to run the boat normally loaded and trimmed at full throttle (Wide Open Throttle, WOT) and check what engine speed you're making. For that engine you should be getting between 4400 and 4800 rpm at WOT. More often than not, the dash mounted tacho is not accurate enough, use a 'shop tacho'...

If the revs are too low (below 4400 at WOT) the engine is lugging, and will be a pig to accelerate and is overloaded, get a smaller pitch prop. The consequences of running the engine overloaded (and with too high a pitch prop that 'overload' is over the entire rev range, not just at wot) include increased engine wear, overheating, burnt valves and detonated pistons. Not to be taken lightly! My preference is to prop to the top end of the rev range. So for your engine I'd be looking at getting it right up to the 4800rpm (and a bit over is not a problem unless you live at WOT). Each 2" pitch change changes the engine speed by roughly 400rpm.

Chris.....
(BTW, my engine would top out at about 5200 if I let it.)

 

[Walt T]

Re: Please help me. Need some advice.

Service intervals are by far more important than the oil you use.

 

[MikDee]

Re: Please help me. Need some advice.

A 19' Monteray is a nice boat. IMO, I think the later model 4.3 V6's (like yours) came with 1.50 ratio outdrives, only the old inline 6cyl. used the 1.65 ratio outdrive. The previous owner might have gotten a good, or better deal on the 260 outdrive, that maybe why it's on there. Don't sweat it, it's basically the same as, if not, newer, & better, then the stock outdrive. If I knew what prop was on it, it would help. I'm guessing either a 19", or 21" pitch prop would be about right to keep your rpm's in the right range with that combo 4400-4800rpm.

 

[thumpar]

Re: Please help me. Need some advice.

I have never heard of a 4.3l that came from Merc with a 1.5 ratio. They should be 1.84.

 

[achris]

Re: Please help me. Need some advice.

Sorry Mike, no V6s ever came with 1.50:1. The earlier 4.3s came with 1.84:1 (I had one) and the later ones come with 1.62:1 (I have one)....

Also the current drive on the boat ('260') is an MC-1 (circa 1980 by the serial number), the drive that was originally on the boat (from new, 1990) would have been an Alpha One. The Alpha One is a superior drive to the MC-1. Better gears, and the lower drive shaft is set-up differently, which is also better.

Chris.....

 

[MikDee]

Re: Please help me. Need some advice.

Sorry Mike, no V6s ever came with 1.50:1. The earlier 4.3s came with 1.84:1 (I had one) and the later ones come with 1.62:1 (I have one)....

Also the current drive on the boat ('260') is an MC-1 (circa 1980 by the serial number), the drive that was originally on the boat (from new, 1990) would have been an Alpha One. The Alpha One is a superior drive to the MC-1. Better gears, and the lower drive shaft is set-up differently, which is also better.

Chris.....

I had an 18' 1974 Wellcraft Airslot with a 165hp Mercruiser "stovebolt " six with a MC-1 outdrive I guess? If I remember correctly it had a 1.65 ratio drive. A great little boat once I rebuilt the "siezed" engine.

So, I guess that's why I thought all the 4.3 V6's had 1.50 ratio drives, I mean I thought that the 4.3 had more balls then the stovebolt to drive that ratio? After all a 1.83 is normally a 4cyl drive? No? By the way, aren't most V8 small block, 305, 350, drives 1.50 ratio?

 

[thumpar]

Re: Please help me. Need some advice.

The 2.5 and 3.0 four uses 1.98. The 3.7 used the same ratio as the V6 at 1.82 or 1.84 or close to that.

 

[tazrig]

Re: Please help me. Need some advice.

...By the way, aren't most V8 small block, 305, 350, drives 1.50 ratio?

Close, a 350 mag MPI is a 1.47:1 or 1.81:1 for high altitude.