1979 MD7A Alternator Replacement - SailNet Community

   Search Sailnet:

 forums  store  

Quick Menu
Boat Reviews  
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Hatches and Portlights
Interior And Galley
Marine Electronics
Other Items
Plumbing and Pumps
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here

Go Back   SailNet Community > On Board > Gear & Maintenance > Engines > Diesel
 Not a Member? 
Old 04-25-2013
H2814D's Avatar
Join Date: Feb 2012
Location: Las Vegas, Nevada
Posts: 78
Thanks: 1
Thanked 1 Time in 1 Post
Rep Power: 4
H2814D is on a distinguished road
1979 MD7A Alternator Replacement

Has anyone replaced the alternator on the MD7A? I need info on a replacement, if so. The current (original) alternator is a sev marchal 70229702, 35 amp, 12 volt. I would rather not try and find another original (freaking expensive) alternator, but a newer, more efficient model. Another reason is because I replaced the tach and need an alternator with a "W" connection to power it. See my other posts for info about that aggravation. :-)

Seems it is more difficult than just going to an alternator website and plugging in the info. The original has a 5" pulley, which gives an approximate 2.5 drive to alternator ratio, which is the ratio needed. All the newer models have 2 and 3 inch pulleys, which are too small for the drive wheel. It spins the alternator too fast. Also, the newer alternators have a 17 mm shaft, and my original is a 15 mm shaft, so no swapping the pulleys.

I know someone out there has had to replace theirs....anyone?

Thanks in advance for any helpful information.

Reply With Quote Quick reply to this message Share with Facebook
Old 04-27-2013
JimsCAL's Avatar
Senior Member
Join Date: May 2007
Location: Glen Cove, NY
Posts: 2,583
Thanks: 2
Thanked 52 Times in 47 Posts
Rep Power: 8
JimsCAL is on a distinguished road
Re: 1979 MD7A Alternator Replacement

Spider Marine lists several alternators for your engine. Here's one.

New Paris Rhone 12v 60 Amp Volvo Penta Alternator: Alternators &amp Alternator

You could call them to ask about the pulley size options.
Reply With Quote Quick reply to this message Share with Facebook
Old 04-29-2013
Join Date: Jun 2006
Location: Spokane Valley WA
Posts: 65
Thanks: 0
Thanked 2 Times in 2 Posts
Rep Power: 9
simpsoned is on a distinguished road
Re: 1979 MD7A Alternator Replacement

ARCO Marine also lists the alternator...Volvo part # 841765 (the 50 amp version) cross references to ARCO part # 80108....and again. you may have to talk to them about the pulley size. I have a 78 MD7A and haven't had to replace mine YET.
Reply With Quote Quick reply to this message Share with Facebook

Quick Reply

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Atomic 4 Alternator replacement TBG Atomic 4 11 01-09-2015 09:17 PM
Valeo Replacement Alternator jonjonza Electrical Systems 1 07-15-2012 11:12 AM
Volvo MD7A Alternator Wiring wedepohl Electrical Systems 0 07-07-2012 02:47 AM
Volvo MD7A Alternator jthomas5 Gear & Maintenance 16 12-15-2008 07:45 PM
1979 Catalina 27 Cutlass Bearing Replacement saurav16 Catalina 2 06-01-2007 08:04 AM

All times are GMT -4. The time now is 07:37 PM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2015, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.