1986 alpha drive outer transom plate the same for a 8cyl and 4cyl?

[lime4x4]

I need to replace the outer transom plate on my 86 mercruiser alpha drive. I have a almost new one that's on a boat that has a 4cylinder engine. Is there a difference between a 8 and 4 cylinder?

 

[Bondo]

Re: 1986 alpha drive outer transom plate the same for a 8cyl and 4cyl?

Ayuh,... If they're both 86s,... I'm going to say they're the Same....

 

[tbear1964]

Re: 1986 alpha drive outer transom plate the same for a 8cyl and 4cyl?

No difference in the transom plate. Only difference is the gear ratios of the drive. Have at it.

 

[Don S]

Re: 1986 alpha drive outer transom plate the same for a 8cyl and 4cyl?

No difference in the transom plate. Only difference is the gear ratios of the drive. Have at it.

Bull Hockey..............


You don't even know what year the "almost new" one is, so how can you say such a thing. What if the "almost new" shield is off a Gen II or a way old 1 drive that looks new???? Is it the same as an 86? Do you know for sure that it will work? I don't!

 

[havasuboatman]

Re: 1986 alpha drive outer transom plate the same for a 8cyl and 4cyl?

That's right!
If the years are the same, he's golden. But there have been some changes over the years.
Lime4x4, what are the serial numbers off BOTH drives?

 

[Fishermark]

Re: 1986 alpha drive outer transom plate the same for a 8cyl and 4cyl?

One difference between the 4 and 8 is the exhaust pipe. The bolt pattern is different for a single pipe versus a "Y" pipe. The transom assembly shown below is for a single pipe.

Now having said that, I removed that transom assembly off a boat I used to own. It came from the factory with a 5 liter Mercrusier and Alpha. The Y pipe was attached to the assembly by only three bolts. Long story short, I finally asked Mercruiser about it and they said that was acceptable.

 

[Fishermark]

Re: 1986 alpha drive outer transom plate the same for a 8cyl and 4cyl?

By the way, I shared this back in 2004 - I did a search and here's what I discovered at the time:

Well, here's the final word from Mercruiser. Their initial response to my question was this:<br /><br />

Thank you for your recent inquiry. The sterndrive and transom assembly do not change regardless of the model of the engine. The setup on the transom side is either for an Alpha assembly or a Bravo assembly. The "Y" pipe setup needs to be the approved exhaust application to work with your 5.7L and Bravo sterndrive. I cannot authorize the use of only three bolts when four bolts was the original planned design. MerCruiser recommends making any necessary changes to insure that both top bolts do line up and attach accordingly. I hope this information is helpful and please let MerCruiser Consumer Service know if we can be of further assistance.

After writng back with a reminder that my boat doesn't have a Bravo drive, but an Alpha one, (as I had originally said!), I received the following response back:<br /><br />

I spoke to a technical expert in the MerCruiser OEM department about how that should bolt up. He said that on some applications that you will only be able to access three holes to complete the assembly. It is completely normal and an approved method. That is officially MerCruiser stance. Sorry for any confusion.<br />

So there you have it - straight from Mercruiser. I guess it's okay to only use the three bolts for the "y" pipe after all!

Here's the post if you want to see the whole thing: Y pipe post

 

[tbear1964]

Re: 1986 alpha drive outer transom plate the same for a 8cyl and 4cyl?

Bull Hockey..............


You don't even know what year the "almost new" one is, so how can you say such a thing. What if the "almost new" shield is off a Gen II or a way old 1 drive that looks new???? Is it the same as an 86? Do you know for sure that it will work? I don't!

I answered the question as written the same as Bondo, except the addition of gear ratios in case he decided to change anything else. He wrote they were '86's. It's in the title. I just didn't infer he didn't know what he was talking about. He asked one question. I didn't play 20 Questions.

Bull Hockey