Alpha Drive reliable ?

[Gordon111]

Mercruiser I/O 5.7 L from 1994 and alpha drive:<br /><br />Hi there,<br /><br />does the Mercruiser alpha drive have a good quality ? (e.g. corrosion problems like the bravo 3). And is it a good combination with the Mercrusier 5.7L (strong enough for the HP) ? In general, assuming a good maintenance level of the I/O engine are 500 hours a lot ?<br /><br />Thanks for your help.<br />Gordon

 

[Mikevn1500]

Re: Alpha Drive reliable ?

Yes

 

[vinney]

Re: Alpha Drive reliable ?

In 1997 mecruiser came out with a heavy duty upper gear set. I have put 500 plus horse power behind an alpha one. Its a great drive. When we have customers that run there drives hard we take them down once a year and ckeck the shim and back lash. If you keep the gear sets in check they will live. Vinney

 

[Mikedg]

Re: Alpha Drive reliable ?

My last boat had an Alpha I, powered by a 5.7l. I ran it for 10 years and 800 hours with no problems. The boat was in the water every year from May through October with shore power. No significant corrosion over the years. Just keep up with the maintenance, i.e. gear oil, seals,and bellows and touch up any dings or scratches.

 

[cmdm151]

Re: Alpha Drive reliable ?

Vinney, you sound like a person that works on boats.If so what knowledge do have the alpha outdrive ahving a whinning noise at 2200-2800RPMs and not at any other spots in the rpm range. This alpha outdrive is on a 2001 Chaparral 196SSi 5.0 EFI mercruiser. Also what oil and filter do recommend?

 

[DJ]

Re: Alpha Drive reliable ?

Gordon111,<br /><br />Yes, the Alpha is a good drive. <br /><br />However, alot depends on how big and heavy the boat is that it is attached to.<br /><br />The Alpha suffers a little bit on big heavy boats because of its limited prop diameter availability. On big rigs, a Bravo is better.<br /><br />On smaller to moderate size rigs-it's great.

 

[vinney]

Re: Alpha Drive reliable ?

The biggest reason for a whine in the lower unit is in the upper gear set. If its been shimed to tight it will ruin the gear set and you can't fix them. The other reason for that gear set to whine is the unit has been over heated. ran low on gear lube. If the gear set is brown in color its been roasted. I see alot of gear set that have been over heated. The unit get run hot and the tech replaces the bad bearings only to save the guy a few bucks. Once the the gear set get roasted it's distorted and will always make noise. I would pull the drive apart and inpect all bearings and gear sets. It's not a big deal for the right guy. Vinney I have asumed you have traced it to the drive.

 

[cmdm151]

Re: Alpha Drive reliable ?

Vinney, I have taken and had 3 dealers test drive it withme and they said this is normaral for this set-up. The ratio is 1:62 I believe. It is in Chaparral 196 SSi that is supposed to have composit stringers. The whine is more of a harmonic whine. You can't here it with the engine cover open but seems to very loud and noticable in the drivres seat. Isthere a way to detect and isolate this? Mercury also said it is normal. If it was in there new $30,000 they would not think it was normal. It is out if warranty is there away to get a rep to listen. The dealer I bought it from said it would not do any good to call the rep because he ( the dealer) was going to tell him ( the rep) that this was normal. The gear oil has been change 3 times 2 years by me just in case. Any sugestions?

 

[vinney]

Re: Alpha Drive reliable ?

I would recommend you put another drive on the boat and run it. If you are dealing with a good shop they will do any thing to prove or disprove the problem. It take 15 minutes to change a drive. I have swap drives befor to prove a point. If the guy is good he wants it right for you. I know there is different gear ratios. Get one that is close as you can. You are looking for a noise not a performance problem. You will know in 30 minutes if its in the drive. Vinney