Proper way to grease impeller?

My one boat runs a 1993 Yama Jet. I know you are supposed to pump grease in the impeller bearing through the port after each use.


How much and is it ok to gently use a grease gun?

I pump about 5 to 8 shots in using a jiffy luber. Grease gun not recommended.

Jiffy Luber: https://www.amazon.com/Plews-30-195...F8&qid=1461934476&sr=8-1&keywords=jiffy+luber

Outboard Jets grease recommendation: https://outboardjets.com/a-change-in-the-type-of-grease-for-driveshaft-bearings/

Awesome - ordered it!


How do you know if you have done it incorrectly? Can you see the seal or otherwise?

Blow the seal and you'll probably start seeing rust and discolored grease. Have to disassemble the pump to get to the bearing seal.

I usually only run for 10-15 minutes going upstream and then float back down. But I still like to give it 1 pump with the Jiffy lube. Grease will start coming out the hose with just 1 pump but it might depend on how long you are running for.

I probably overdo mine, but usually pump it about 10-12 times or until a decent amount of grease comes out. I collect the used grease on a paper towel so I can inspect for water.

I also use a jiffy luber, but started out with a standard grease gun and just applied grease VERY gently. The jiffy luber is fool proof though and a worthwhile investment.

Ok, this thread was started due to my ignorance. Capt Ahab was generous enough to lend his boat to me. And after getting ready for the water I took it out to the local lake and ran the gas motor for 15 mins or so. Upon getting home I figured it would be best to grease than not to. So I proceeded to put grease in with standard grease gun and I did so very carefully and slowly. I felt as if I was not going in so I removed the rubber tube and fitting to verify grease was coming out. I thought maybe the grease in rubber tube may have been dry/hardened as it sat for awhile. I pumped in enough grease to get a 2.5" to 3" line of grease out of it. I'm concerned I put too much in and/or the gun was to much pressure. Again I didn't just shoot it in, very slow pull of handle. I dont want to put back in water if I could damage other components. Should I take this to get inspected, see if seals are popped out. Or is there a way to tell if they are blown out. Please let the comments fly, good, bad or other.

Pumping in grease without using the overflow properly is a def no-no. Two ways to tell if the seal is damaged...disassemble pump and inspect....keep running it and look for discolored grease from rusted barrings, blueish/black tint to grease from metal-on-metal wear; and water in the grease. If you see signs that match the last 3, may be produent to replace seals before catastrophic failure. A drop or two of water in old grease is normal from what I've seen.

Hopefully, other's will chime in with second opinions.

Fishstix said:

Ok, this thread was started due to my ignorance. Capt Ahab was generous enough to lend his boat to me. And after getting ready for the water I took it out to the local lake and ran the gas motor for 15 mins or so. Upon getting home I figured it would be best to grease than not to. So I proceeded to put grease in with standard grease gun and I did so very carefully and slowly. I felt as if I was not going in so I removed the rubber tube and fitting to verify grease was coming out. I thought maybe the grease in rubber tube may have been dry/hardened as it sat for awhile. I pumped in enough grease to get a 2.5" to 3" line of grease out of it. I'm concerned I put too much in and/or the gun was to much pressure. Again I didn't just shoot it in, very slow pull of handle. I dont want to put back in water if I could damage other components. Should I take this to get inspected, see if seals are popped out. Or is there a way to tell if they are blown out. Please let the comments fly, good, bad or other.

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What type of grease was loaded in your grease gun?

It was a red marine grease recommend by a local boat works. I think it gonna need to be pulled and inspected.

I don't think you can put too much in, any excess will come out the hose. If you really forced it and the hose was clogged, then it could have gotten past the seal I guess. I don't think you would have damaged the bearing yet. If you take it for a short run, then put some more grease in you can check for water coming out. That would indicate the seal being bad and would lead to the bearing getting rusted and going bad eventually.

You cannot put in too much grease as long as it is coming out of the hose. The most important thing is that you don't use too much pressure.

My main concern would be the type of grease used. Make sure it is a NLGI 1 type grease. I have always used Outboard Jets recommended grease and have never had a bearing failure. I pump it in after each outing and after around 7-8 trips I flush the old grease out with fresh grease. It should flow easily, you shouldn't have to use any force. I hold the hose with a rag or paper towel and pump until the new grease comes through. The old will be runny and usually have a light gray tint. If it is real dark the bearings are probably going to need to be replaced soon.

This is from Outboard Jets FAQ section.
[10. Can you use any other grease besides Lubriplate 630 AA and why do you recommend against using a lever type grease gun?

Any grease of the same consistency (NLGI 1) which is water resistant should do the job. The main thing is to keep grease in the bearing cavity and water out. We prefer a hand held jiffy lube since it does not create high pressure. If a cartridge type lever gun is used, it should be pumped gently! Excessive pressure will invert the rubber seal lips and seals will no longer keep water out.]

There is no way to inspect it without disassembling it. I would run it, pump the grease in after and see if any water comes out. If it doesn't you should be good to go.

You guys are great - thanks for all the help. Will post after the next run so we can see the results.

I HIGHLY doubt there is a problem but all teh great advice here gives me peace of mind.

Tight Lines

Here is a tip Captain, use a 'zip-lock' sandwich bag to catch the grease. You can thoroughly inspect the grease and NOT get it all over everything( i.e. hands tools motor,etc.).

S&MFISH said:

Here is a tip Captain, use a 'zip-lock' sandwich bag to catch the grease. You can thoroughly inspect the grease and NOT get it all over everything( i.e. hands tools motor,etc.).

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Zip-locks work great, I usually never have one in reach when I need it. That grease does make a big mess if you don't contain it in some way.

I use a water bottle to catch the grease.