Reply
 
Thread Tools Search this Thread Display Modes
 
Old 06-04-2015, 10:01 AM   #1
Guru
 
Capt. Jon's Avatar
 
City: Alabama
Vessel Name: Waypoint
Vessel Model: Californian 48' CPMY
Join Date: Dec 2013
Posts: 506
Cat 3208 Alternator Improvement

I have looked around trying to find a replacement for the standard 51 Amp small frame alternator on the 3208. Would like to install a larger frame unit but the current mount will not allow it. Anyone ever tackled fabrication of a different mount to install a larger framed unit?
Capt. Jon is offline   Reply With Quote
Old 06-04-2015, 01:48 PM   #2
Guru
 
River Cruiser's Avatar
 
City: UMR MM283
Vessel Name: Northern Lights II
Vessel Model: Bayliner 3870
Join Date: Jan 2013
Posts: 1,357
I've made several mounts during my working years for alternators and pumps on engines. The most important thing is locating the alternator so the belt alignment is true, the rest is just cutting, drilling and welding. I would build the mounts so I could adjust alternator position with shims to get correct belt alignment, washers will usually work for this.
__________________
Ron on Northern Lights II
I don't like making plans for the day because the word "premeditated" gets thrown around in the courtroom.
River Cruiser is offline   Reply With Quote
Old 06-04-2015, 04:02 PM   #3
Valued Technical Contributor
 
DavidM's Avatar
 
City: Litchfield, Ct
Join Date: Aug 2012
Posts: 6,786
Post your question on boatdiesel. Dave (not me), the resident Cat guru may have some ideas and maybe there is a Cat part available to mount a larger alternator. Dave will know. There are a lot of 3208s in service and you aren't the first person who wanted more amps.

51 amps? Even an 18 hp Yanmar diesel has a bigger alternator than that.

Also you might want to call Balmar. They sell high output, externally regulated alternators. A small case one that replaces the 55 amp Hitachi on the Yanmar noted above can put out 100 amps with a single belt, more with two. So they might have an alternator that could drop in to replace your puny one.

David
DavidM is online now   Reply With Quote
Old 06-04-2015, 05:49 PM   #4
Guru
 
Alaskan Sea-Duction's Avatar
 
City: Inside Passage Summer/Columbia River Winter
Vessel Name: Alaskan Sea-Duction
Vessel Model: 1988 M/Y Camargue YachtFisher
Join Date: Jul 2012
Posts: 8,050
Give these folks a call:


Starters, Alternators and more for Cars, Trucks, Tractors and ATVs
Alaskan Sea-Duction is offline   Reply With Quote
Old 06-04-2015, 09:29 PM   #5
Guru
 
Capt. Jon's Avatar
 
City: Alabama
Vessel Name: Waypoint
Vessel Model: Californian 48' CPMY
Join Date: Dec 2013
Posts: 506
Talking

Quote:
Originally Posted by Alaskan Sea-Duction View Post

Thanks ASD, I have used these guys before in the past. Bought a starter for a Kohler gen set from them several years ago. I did not even think about calling them! Maybe I can find a larger output in the same frame size currently on the engine.
Capt. Jon is offline   Reply With Quote
Old 06-04-2015, 10:29 PM   #6
Technical Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 6,194
Tough one. The butt end of that little Motorola is real close to exh manifold. A big one is not going to fit there.
Ski in NC is offline   Reply With Quote
Old 06-05-2015, 12:27 AM   #7
Guru
 
City: Anacortes
Join Date: Nov 2012
Posts: 1,189
Balmar used to make a small frame 100 amp that would fit. I say used to, as I'm pretty sure I got two of the last three they made and this was a few years back. I use a center fielder in addition to the regulators to be able to pump both 100 amp alternators into a single bank. That's how I got to my 200 amps. I then use a charge controller to keep the starting bank up.

Otherwise you will have to make custom brackets and the alternator is going to have to sit in a not so great location. I might consider a real custom bracket to allow you to flip the alternator so it's not in the way.

I suspect somebody must make a high duty small frame alternator, but it might take some research. Maybe a call to balmar or an alternator shop to find someone to build one. I mean, once they put in decent bearings and diodes, that's pretty much it.
ghost is offline   Reply With Quote
Old 06-05-2015, 08:15 AM   #8
Guru
 
Capt. Jon's Avatar
 
City: Alabama
Vessel Name: Waypoint
Vessel Model: Californian 48' CPMY
Join Date: Dec 2013
Posts: 506
Quote:
Originally Posted by Ski in NC View Post
Tough one. The butt end of that little Motorola is real close to exh manifold. A big one is not going to fit there.
Yep, real close! Like just a few mm's!

It's been my experience with small frame high output alternators that heat soaking gets to them. Hence the question about the mount. Just thought someone had already done this and could post an example of what they did to solve the mounting issue. Just did not want to re-invent the wheel so to speak.

It maybe my best option are two small frame high output to get the amps I want.
Capt. Jon is offline   Reply With Quote
Old 06-05-2015, 09:46 AM   #9
Valued Technical Contributor
 
DavidM's Avatar
 
City: Litchfield, Ct
Join Date: Aug 2012
Posts: 6,786
Presumably you need the amps to recharge a big house bank fast, right?

If so two of the OEM type alternators won't cut it. And particularly if you are going to the trouble of designing a second mount, make it so that it can handle a high output alternator.

First your OEM alternator is internally regulated. These alternators put out a fixed voltage and will not charge a house bank very fast. With an 80 amp internally regulated OEM alternator on my boat, it quickly drops back to 20 amps whereas an externally regulated alternator would keep the current high for much longer, thereby reducing charging times.

Even if you could add an external regulator, it is still a wimpy OEM alternator that is not designed to put out its rated amperage long term. High output alternators have better fans, diodes and heavier windings to deal with long term high output.

What you really need is a Balmar or similar high output alternator. Leece Neville and maybe Delco make some that are designed for emergency equipment that work fine at high output. But they are unlikely to fit your current mount.

David
DavidM is online now   Reply With Quote
Old 06-05-2015, 05:22 PM   #10
Senior Member
 
Lutarious's Avatar
 
City: Oakland,Ca
Join Date: Sep 2014
Posts: 108
Where are you located? There's a place in Oakland Ca called Northstar that repairs and rewinds altrrnators. They can do miracles with the stuff you drag in there. Look around and see if yours can be rebuilt for higher output.
Lutarious is offline   Reply With Quote
Old 06-06-2015, 04:59 PM   #11
Guru
 
motion30's Avatar
 
Join Date: Jan 2010
Posts: 1,181
I replaced my stock alt with a 90 amp unit, exact same size
motion30 is offline   Reply With Quote
Old 06-06-2015, 05:21 PM   #12
Guru
 
Capt. Jon's Avatar
 
City: Alabama
Vessel Name: Waypoint
Vessel Model: Californian 48' CPMY
Join Date: Dec 2013
Posts: 506
Quote:
Originally Posted by motion30 View Post
I replaced my stock alt with a 90 amp unit, exact same size
Yes, found brand new prestolite 91 amp for $176 shipped. I can't even get my 51 amp Motorola rebuilt around here for that price!
Capt. Jon is offline   Reply With Quote
Old 06-06-2015, 08:06 PM   #13
Guru
 
Capt. Jon's Avatar
 
City: Alabama
Vessel Name: Waypoint
Vessel Model: Californian 48' CPMY
Join Date: Dec 2013
Posts: 506
Quote:
Originally Posted by Lutarious View Post
Where are you located? There's a place in Oakland Ca called Northstar that repairs and rewinds altrrnators. They can do miracles with the stuff you drag in there. Look around and see if yours can be rebuilt for higher output.
Orange Beach, AL. A longs ways away from Oakland!
Capt. Jon is offline   Reply With Quote
Old 06-07-2015, 02:03 AM   #14
Member
 
City: Sidney BC
Join Date: Sep 2014
Posts: 7
Alternator improvement.

I had both my stock 3208 alternators rebuilt to produce ove 100 amp each. Don't know what they did but they work great.
maac16324 is offline   Reply With Quote
Old 06-07-2015, 06:49 AM   #15
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 22,553
When comparing alts ,always request the HOT rating.

It may be 50% of the cold rating, so not great for a boat , but really fine to run a car amp for a Boom Box car.

Size matters when it comes to cooling .

Some of the higher powered units for trucks and buses will use the engines oil to cool the unit.

90-100A HOT is a lot to ask from a small frame unit.

135 A from a large frame truck unit is under $150 brand new

To go cheap the old big cars (caddy) used 75A units with external regulators , that can be had rebuilt from Auto Zone style shops for about $50 rebuilt.

The Delco external regulator hookup will accept an aftermarket marine regulator.
FF is offline   Reply With Quote
Old 06-07-2015, 04:08 PM   #16
Guru
 
Alaskan Sea-Duction's Avatar
 
City: Inside Passage Summer/Columbia River Winter
Vessel Name: Alaskan Sea-Duction
Vessel Model: 1988 M/Y Camargue YachtFisher
Join Date: Jul 2012
Posts: 8,050
Quote:
Originally Posted by Ski in NC View Post
Tough one. The butt end of that little Motorola is real close to exh manifold. A big one is not going to fit there.
Good point! In fact, make sure you have the rubber booty on it to!!!
Alaskan Sea-Duction is offline   Reply With Quote
Old 06-07-2015, 04:11 PM   #17
Guru
 
Alaskan Sea-Duction's Avatar
 
City: Inside Passage Summer/Columbia River Winter
Vessel Name: Alaskan Sea-Duction
Vessel Model: 1988 M/Y Camargue YachtFisher
Join Date: Jul 2012
Posts: 8,050
Quote:
Originally Posted by Capt. Jon View Post
Yes, found brand new prestolite 91 amp for $176 shipped. I can't even get my 51 amp Motorola rebuilt around here for that price!
Where?
Alaskan Sea-Duction is offline   Reply With Quote
Old 06-19-2015, 07:14 PM   #18
Newbie
 
Join Date: Nov 2013
Posts: 1
It is pricey but you can get a smart charger that connects to your Alternator, that puts out 210 amps or as needed to your House bats.....anyone had any experience with that?
Hack is offline   Reply With Quote
Old 06-20-2015, 05:28 AM   #19
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 22,553
Any voltage regulation system is limited to the basic output of the alt.

Most alts are limited by their ability to cool ., which is why the HOT output is frequently minor.
FF is offline   Reply With Quote
Old 06-20-2015, 08:24 AM   #20
Guru
 
Capt. Jon's Avatar
 
City: Alabama
Vessel Name: Waypoint
Vessel Model: Californian 48' CPMY
Join Date: Dec 2013
Posts: 506
Quote:
Originally Posted by Alaskan Sea-Duction View Post
Where?
I have it saved on my computer at work. I'll post the link next week.
Capt. Jon is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Trawler Port Captains
Port Captains are TF volunteers who can serve as local guides or assist with local arrangements and information. Search below to locate Port Captains near your destination. To learn more about this program read here: TF Port Captain Program





All times are GMT -5. The time now is 09:57 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012