Just purchased a 1985 E35 !


Member III
Location: Lake Travis, Texas (Austin). Going to be a restoration of sorts and my lower purchase cost reflects work ahead. Getting the bottom redone this week...zebras in mass! Can't stop reading this forum and learning a lot, plus going through the extensive manuals. Engine is original Universal 25 and in great condition with less than 1000 hrs. Doing the air cleaner K&N RU-0370 mod plus Lots of questions coming your way...to begin with, I ordered the Alternator low bracket mod. I searched this forum and got a lot of great info on this mod...question: Folks recommended replacing the original alt. for a 90 amp. Why? Also question #2, is the correct recommended oil filter the NAPA/Wix 1064 that will fit behind the low alt bracket? Lots more questions in the future; please be patient...in my much younger days I was a 6 year Sea Scout and 1 year commodore...plus owned another 22' Chrysler sloop a several decades ago so I am in love with sailing! Presently retired Law Enforcement (pilot) so living on Uncle Sugar retirement has its limits!!! Thanks!! Larry

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
Cannot provide all answers, but can confirm that the spin-on oil filter *has* to fit where the hose elbow goes back down the side of the block and the alternator bracket is. Crowded area.
I lived happily with the factory Moto 50 alternator on our M25XP, until repowered last year with a new Betamarine25 with a 70 amp alternator. No reason to change up, just seems like a good idea for the future.

Christian Williams

E381 - Los Angeles
Blogs Author
A more powerful alternator with an external "smart" regulator (which customizes the output for efficiency) just charges the batteries faster. You can make up for the day's ampere usage in less than an hour, whereas with a stock 50 amp alternator (which puts out only a steady charge) that might take hours of engine time.

It seems to me that alternator output only really matters for cruising, since shore power generally keeps the batteries topped off for daysail use. And of course, we motor a lot during a typical family cruise, in which case the stock alternator will top off the batteries anyhow.

Sean Engle

Your Friendly Administrator
Going to be a restoration of sorts and my lower purchase cost reflects work ahead. Getting the bottom redone this week...zebras in mass! Can't stop reading this forum and learning a lot, plus going through the extensive manuals. Engine is original Universal 25 and in great condition with less than 1000 hrs.
Congrats and good luck on the restoration! When I got my boat I had a good diesel mechanic run over it to ensure there were was nothing afoot which I might make worse. He checked all the main stuff, valve clearances, compression, etc. It was well worth the money...



Member III
Thanks folks...this is an exciting experience and this forum is unsurpassed as a knowledge base.......!


Member III
I just upgraded to a 70A alternator with external regulator. The stock alternator is a 50A model with internal regulator which is designed for cars/trucks, just to top off the charge used to start your engine and run headlights and the radio. The regulator just puts out a steady voltage which provides a lot less current than the battery needs to recharge fast. Plus a deep cycle battery puts a lot more strain on it as well having to charge for extended periods which it wasn't really designed for. A high output alternator with external regulator properly charges your deep cycle with high-current high-voltage bulk-charge, then an absorption phase, and finally a float (trickle charge) so you can replace a night's battery use in less than an hour of motoring. A 90A alternator is about the limit you can go before you need dual belts or a serpentine belt. The external regulators also let you program a "belt loading" to reduce the top current draw which you might consider if your belt is getting eaten quickly.

Us East-coast sailors are more often then not sailing off a mooring and don't have the luxury of shore-power and battery chargers so a good alternator and a solar panel are nice additions.

Figure out which Kubota tractor your Univeral 25 was based on and that will go a long way towards finding the right parts at the right price

Good luck!

Kenneth K

Sustaining Member
Blogs Author
Congratulations. The alternator bracket upgrade is not hard, but it does present a lot of "while you're in there" opportunities for add-on projects. You'll likely have to remove the water-cooled exhaust manifold to install the longer studs for the new alternator bracket. While you've got the manifold off (and, while it's not sailing season), it probably makes sense to have both the manifold and the heat exchanger boiled clean, the exhaust elbow inspected (and likely replaced), replacing the hoses you've removed along the way with new ones, and maybe replacing the fresh-water pump while the engine is drained. These added several days to my project.

When you re-install the alternator, you might as well disable the problematic ammeter/charging circuit (orange wire) and add a small gauge jumper wire from the alternator directly to the starter post (as discussed in most of the "engine panel upgrade" posts and blogs.

Although replacing the wiring trailer connectors can be important to address, a 2 minute inspection of your own will tell you if they are presently corroded/overheating, or if it's a problem you can put off for down the road. And, deactivating the "orange wire" probably eliminates the biggest threat in the trailer connectors any way.

Tom Metzger

Sustaining Partner
Larry - I'm not sure anyone actually answered your alternator question. If you have lots of "systems" on your boat it is important to be able to recharge quickly if you're out for multiple days. The most obvious system is the fridge which is a power hog. Next would be an inverter, the ultimate power hog. If you don't have systems you probably have no use for a larger alternator.

In my previous boat I was very happy with a 35 amp dumb alternator for 18 years without a charger. We powered for a mile or so when we left the dock or anchorage to recharge. Our only "system" was an autopilot.

Here is a link to the engine wiring changes that Ken mentioned. Being in fresh water some of the other things he mentioned may not be necessary. https://ericsonyachts.org/ie/threads/universal-diesel-wiring-modifications-how-to.12178/

I use a Napa/Wix 1334/51334 or Fram PH3593A lube oil filter.