• If this is your first visit to the iboats.com Boating Forums, be sure to check out the FAQ. To post a question or comment, begin by signing up. To start viewing messages, select the forum that you want to visit from the selection below.
  • ALL iboats Forum Members and Guests:
    To show our appreciation for your participation in the Forums, we're offering an exclusive Forums-only discount good for an additional 5% off your iboats.com order for a limited time.
    To redeem, simply call our Customer Service Team at 800-914-1123 (Open M-F, 9am - 8pm Eastern Time) and mention the Forums 5% off discount. Offer excludes engines, trolling motors, and electronics.

Announcement

Announcement Module
Collapse

Help Tip: If you have a question that has not been answered to your satisfaction in the archives, it is always best to start a new thread of your own. By starting your own thread, you will receive the maximum number of views by forum members.

Below are some additional forum policies in hopes of all iboats members will follow, Thank you.

1. Please do not reply to old threads or hijack existing threads. Old threads of a technical nature are like a library book, Please do not write in them.

2. Old threads should be considered archives and used for reference only. Please do not reply to them.

3. Do not take over someone elseís thread (aka hijack) with your own question, even if it is similar. If you have a question that has not been covered to your satisfaction in the archives, it is always best to start a new thread of your own.

4. If you have a question for the original poster (OP) and the thread is over 30 days old, send the OP a PM, he may not even visit the forums any longer, or may not notice your question in the old thread.

5. By starting your own thread, you will receive the maximum number of views by forum helpers that may not even notice your question when itís posted at the end of someone elseís thread. And those answers will be specific to your particular issue.

6. Please do not post to threads that have been inactive for more than 3 months unless you are the original poster. We have very active forums and any thread that remains inactive for that long should be considered "dead". It is especially confusing when there is an entirely new question posted to an old thread.

7. Posting at the end of any thread is considered to be hijacking the original posters thread which in turn subjects the thread to be closed if it continues to happen thus not making it fair to the original poster in the future had for some reason he/she needed to return for additional information or provide an update of the problem solved which is always welcomed within a reasonable amount of time frame.

8. Please note that you should see a red banner pop up near the bottom of each inactive thread asking you not to reply to old threads. The Red banner will read: Please note this thread has been inactive for 90 days. For the best results, please start a new thread.

Thank you all in advance for doing your part in helping iboats run a smooth ship.

Additional forum rules linked below.
http://forums.iboats.com/forum-rules-guidelines-405/
See more
See less

Lower Unit Oil??

Page Title Module
Move Remove Collapse
X
Conversation Detail Module
Collapse
  • Filter
  • Time
  • Show
Clear All
new posts


  • Lower Unit Oil??

    I had a question regarding regarding Lower Units. I have a 1975 55 HP Chrysler. To my knowledge the lower unit oil has never been changed. When I change this oil should I expect and problems? Will it be real thick or thin? I'm just trying to anticipate any problems before I take out the screws. Any advice? I've heard the lower units be compared to the rear end of a car. Is this a correct illustration? Is the oil in the lower unit similar to the oil that would be in the differential? I'm just trying to get a better idea at how all of this works. I'm still quite the novice Thanks,Shane


  • #2
    Re: Lower Unit Oil??

    It should be just like the gear oil in a rear end. Remove the drain plug and also the vent plug.If it has been sitting for more than a week or two, you might see a few drops of water come out first. More than a few drops of water can indicate need for attention. Like seals replacement. If rusty water comes out that is bad. It is usually suggested here to replace the washers on the plugs as they sometimes leak water in if they don't seal well upon reassembly.I usualy use a good grade 80-90wt gear oil and buy a couple of quarts. With two quarts on hand I can cut the tip off one bottle and push it into the lower drain hole. Then squeeze till you can't squeeze any more. Now remove the bottle while putting your finger on the hole while your assistant refills the bottle from the second quart. Then squeeze in some more till it runs out the top vent hole.

    Comment



    • #3
      Re: Lower Unit Oil??

      There are 2 key indicators when replacing lower unit oil : If it is grey in color you have water in the system, the next is to check for small particals of metal, which indicates some gear mesh problems. You should be changing the lower unit lube at least 1 time per season.

      Comment



      • #4
        Re: Lower Unit Oil??

        SHANE, I bought a little gadget that makes the job a little easier with less mess. One end replaces the cap on your bottle of gear oil and has a "finger pump" similar to a bottle of hand soap. A short hose connects to a fitting which is threaded to fit the bottom hole. Remember to remove the top plug after you get the fitting tight and you're in business. To add a 2nd bottle, just switch the pump to the new bottle and continue. A good investment for about 5 bucks at Walmart or K-mart. Have a great day. -G.

        Comment



        • #5
          Re: Lower Unit Oil??

          It is alot like a car rear axle meaning hypoid. I would not use an automotive lube in them though. Use a marine 80 to 90 weight gear lube.

          Comment



          • #6
            Re: Lower Unit Oil??

            Their are three API service categories for gear oils.API-GL1, API-GL4, API-GL5.Most outboard manufactures recommend API-GL5 gear oil for their lower units. API-GL5 gear lubricants are for both mechanical shift units calling for type B gear oil and electrical shift mechanisms calling for type C gear oil (only the viscosity value will be different for each application)

            Comment



            • #7
              Re: Lower Unit Oil??

              I KNOW ONE THING IF THE LUBE COME OUT LET'SSAY NOT THE BEST I WOULD CHANGE THE LUBEEACH TIME FOR ABOUT 3 RUNS. THEN IF IT LOOKSBAD LIKE MILK THEN YOU KNOW YOU GOT BAD SEALI KNOW TRENT AND I DO NOT AGREE ON THIS BUTYOU COULD SPRAY THE SEAL DOWN WITH BRAKEFUILD TO SOFTING THEM UP. IF THEY GET A SOFTTHEY MIGHT START TO SEAL FOR YOU.BUT CHANGE THE LUBE EVERY TIME FOR THE FIRST2 OR 3 BEFORE IT COST YOU ABOUT $300.00TO WORK ON THE LOWER UNIT.I HOPE YOUR NOT MAD TRENT.GOOD LUCKREX A HUBBLE

              Comment



              • #8
                Re: Lower Unit Oil??

                Rex.. Iv never been mad at you. I just disagreed with you on the brake fluid thing.. If it works for you, go for it!! But I will just replace the seals. But what the heck do I know

                Comment

                Working...
                X