Johnson V4 93 88 SPL Lower Unit Having Issues

Well on top of my other other issues which are being handled in another thread, I am having lower unit problems.

Last week when cruising around, I noticed I had a hard time finding neutral. I had no issues finding reverse or forward. But I would have to play a little at time to get neutral. So I decided to adjust the trunnion to see if it was a simple adjustment. After a small adjustment I now had good neutral, good forward but when I went to reverse the outboard would rev before the gears would change. so I adjusted the other way a little, now got the opposite effect. Reverse no problem, easy neutral and revs before forward gear would engage. The RPMs would get over 2k before it wanted to engage. So I was able to play with it and get it to an acceptable position.

I got it out of the water and tried to pull the drain and vent screws, but am having a problem with them. The last shop I brought it to said they put them on with an impact gun. I tried my impact to tack them out with no luck. I loose grip before they spin, so any help getting this out would be great. Any tricks to getting them out is appreciated. Once I get them out I can get a better idea of metal and fluid color. Other then that what else should I do? What else would cause this? The cable seems to be fairly new and it seems to shift the shift rod correctly. Any help is greatly appreciated, thanks again for all the help.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

When the vent and fill plugs are very tight, you will need a 1/2" screwdriver and a strong hand to remove them. If you have a hand impact tool it may work if you have the 3/8" or 1/2" bit. The large 3/8 bits come with most of the less expensive hand impact kits, but the 1/2" on in my snap-on kit is too thick for the slot. The snap-on 7/16 SW28E works OK.

I'd go for the 1/2" screwdriver and a 6 pack for the biggest kid in the neighborhood.

I've never had a plug come out on me but I always use new seals. I just get them as tight as possible by hand with my screwdriver.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

I will try that, the first shop I brought my boat to told me to use an impact gun. Didn't seems right to me. I may actually be the biggest kid on the block who could use a six pack, so ill get on it!

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

I got the 2 plugs out, thanks ezeke! I also earned a 6 pack along the way! I ended up taking an old steel file and grinding it to fit the slit perfectly. Then grabbed a set of pliers and turned, worked great. Now the problem.

When I drained the fluid a small amount of water came out first then some small amounts of water with lube. I was told it needs new seals by the shop, this confirms it for me. I am sure it is not the drain plug holes. So what seals should I replace? I am already going to pull the lower unit to replace the water pump. I have the manual but it only seems to assist in work on this motor not actually how to do the job. Any help is appreciated, thanks for your time.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

pressure test the lower and see where it is leaking. that will tell the story.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

I would like to replace any seals I can while I have the lower unit off for the water pump service. I am now trying to take the lower unit off but am having a hard time getting the shift rod off. I got the pin out no problem. My manual says push towards the power head and remove. I tried that with no luck. Any help here is appreciated. Thanks for your time.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

Got the lower unit off, just needed a spin of the flywheel. Whats seals can I replace while the unit is off. I already ordered the water pump kit, so anything other then that. Thanks for the help.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

Get a seal kit if you want to redo the gearcase. http://www.iboats.com/Johnson_Lower...z.36857--**********.736699052--view_id.271288

You will need seals for the prop shaft, the driveshaft, the shift rod, the vent and fill plugs, and the bearing carriers, they all come in the kit.

The easier ones are the shift rod and drive shaft.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

I already pulled the lower unit apart up to the large C clips. The prop seal had lots of crud around it and didn't seem to look like it would make a good seal. I also pulled the water pump and noticed the black seal for the pump cover was installed wrong. I could clearly see where the seal was pinched. What is the most difficult seal to replace? Thanks for all the help.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

Once you have the bearing carriers out, the shaft seals are not that hard.

The two o-rings that form the shift rod seal can be a bear the first time; You bend 'em double and shove them in with a drop of oil, line them up with a pair of small dowels and you are done. You have to unscrew the shift rod so that means you will have to reset the shift rod length after you are finished. You can get the old o-rings ones out with large sail needles or make some picks with your grinder out of heavy coat hanger wire.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

Have the pressure checked to find the leak and go from there...it will give you a good reference point. Man I am ready for Spring Fishing.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

Do you recommend the full kit? There was not a lot of water in the gear oil. If I can get away with a prop seal and new water pump seals I would be happy. Basically I would like to stay away from resetting the shift rod length. This is my first LU so maybe I am making it harder then it is. I got to this point real easy, so I guess I open to doing the job right.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

The shaft seals alone run almost as much as the kit. The large o-rings that seal the bearing carriers should be replaced. The shaft seals are either two each back to back or double faced.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

So should I start with the large O rings? I don't mind taking the unit down again if this is not the problem. The carrier came out fairly easy without needing the puller. What is the leading 2 causes of water in the LU? Are the large O rings one of them. Thanks for all the help.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

I am doing the seal kit tomorrow for the LU. I am a little unclear on the shaft adjustment. I have not taken the shaft seal off yet, is there a trick to the shaft adjustment? Any other tricks to this job would be great. Thanks for the time.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

The shift rod length will be specified in the last page of the Gearcase section of your service manual. I think that yours will say 21-27/32 for the long shaft and 26-27/32 for the extra long shaft. That's measured in neutral with the offset at the top facing forward.

You can make a measuring tool out of a pair of inexpensive yard sticks with a crosspiece set for the height specified. You need to measure from the mating surface of the gearcase to the center of the hole at the top of the shaft. The shaft has normal threads, so clockwise shortens.

Re: Johnson V4 93 88 SPL Lower Unit Having Issues

Great, I will get at it in the morning. Thanks for the help.