volvo 270 out drive

[happytrailsr]

I recently purchased a used 270 outdrive off of an aq 131 to use as a spare in case i ever had trouble with the 270 on my 24 ft. bayliner ciera (225E)engine.I've been told I can't use this outdrive with this engine because of differnt gear ratios in the lower unit. this dosent make any sense to me. I t seems to me that rpm's are rpm's no matter what size engine supplys them. will someone please clarify . Thanks Ronnie

 

[Don S]

Re: volvo 270 out drive

I'll put this in very basic terms. Your engine (225E Chevy V8) has a lot more power than a 131 (volvo 4 cylinder)
So the gear ratio is changed so the smaller engine can still use the same size prop as the V8.
This keeps the prop in the BEST working range of a prop.

Basically, whoever told you that, is quite correct. You can't even change prop sizes enough to cure that one.

 

[Bondo]

Re: volvo 270 out drive

Ayuh,.....

What Don says is the Truth,..... It's all about Available HP,+ the Prop Speeds....

Btw,......
Welcome Aboard to the forums here at iboats.com.....

 

[happytrailsr]

Re: volvo 270 out drive

thanks guys , i know you're right .I was engineer on a 5000 hp. tow boat for many years . but for some reason ijust can't get it right in my mind how this works. I'm still stuck on rpm' of the drive shaft .this boat will still run if you' pull a couple of plug wires off. thanks again , old age has set in.

 

[Don S]

Re: volvo 270 out drive

The prop needs to turn at a certain speed (RPM) Depending on the HP and torque, you will need different gear ratio's to turn that rpm.
Even on big boats, you need different gear ratio's in the transmission. Very few will run slow enough rpm to turn the prop without a gear reduction of some kind.

 

[whywhyzed]

Re: volvo 270 out drive

......

 

[mcleaves]

Re: volvo 270 out drive

whywhyzed has woken me from my stupor and pointed me to the correct thread to post this

I forget how it is on the AQ series, but isn't the gearing change just in the upper or the lower. What I am getting at is he may have half a drive

 

[Don S]

Re: volvo 270 out drive

Yes, and he would have a little over half a drive. The gears could be changed, BUT. A new set of lower gears has a retail price of $2.394. No bearings, no seals, no labor changing them.
So unless he can find a 1.61: 1 lower, it's basically a spare upper gear box. But then it has to have the same kind of helmut screw as his present drive (3 choices), or there are even more problems with fixing that. And that would be $450 for the clamp ring change, oh, that's parts only not labor.
OLD Volvo drives are not a way to save money unless you are real lucky finding the right part.

 

[mcleaves]

Re: volvo 270 out drive

Got it.. Yeah I know from experieince how expensive those things are. I still have my old 270 I bought as a backup for a couple hundred sitting in my garage.

But since he already has the drive he can either sell it or treat is as a spare upper. The retaining pawls are worth some coin too if they are in good shape

M

 

[happytrailsr]

Re: volvo 270 out drive

thanks fellows, i'll keep this drive there a few things like the exaust flap,reverse latch etc that i can use . i wish i had found this forum earlier.hope that i'll be able to contribute something in the future. Ronnie