Air but no water coming out of telltale

[sberl]

The motor is a 1987, 35 horse that I bought about a year ago. When I bought it the owner had it on mufs and started it up and it ran great with water streaming out the hole. The motor has just been sitting while I’ve been restoring the rest of the boat. Started it up today no problem but there is no water exiting the telltale. I removed the hose and can blow thru it no problem. Also, with the motor running I can feel air being blown thru it. Does it sound like it needs a new impeller?

Thanks!

 

[mbhoag]

In my NON expert opinion, I would say that anytime you run a motor there are 3 times you need to replace the impeller

1. You run the engine and do not have water coming out the telltale, you need an impeller replacement.
2. If you run a motor for more than 30 seconds without water, you need an impeller replacement.
3. If you even question if your impeller has been in the boat too long, you need an impeller replacement.

Impellers are cheap, motors are expensive.

 

[sberl]

Thanks for the advice! I think I’ll order a replacement kit tomorrow. I’ve watched some YouTube vids of replacing the impeller on other motors but not my specific motor. I’m assuming they’re all pretty similar? Any suggestions on where to get the kit from?

Thanks,
Steve

 

[jbuote]

You can get them right here at iBoats.

Go to the shop tab, and click on OEM Part Finder. Enter your model information and then gearcase (driveshaft) section I believe for your kit..

For example, I found this kit which includes the housing, impeller etc..
http://ww2.iboats.com/PUMP-KIT-WATER/dm/cart_id.980662107--session_id.533796049--view_id.1629951

This link may not be exactly for your engine, but it's for 1987-1989 Mercury 35hp outboards.
Use the finder to be sure you match to your engine though.

Don't forget, iBoats will price match, and then there's the forum 5% discount code too!

Hope it helps!

 

[Tassie 1]

Also keep an eye out for an old 44 or equivalent " plastic" size drum that you can cut down so the lower unit is completely in the water,
No doubt then that water is actually going through

sometime muffs don't get put on exactly where they should be or slip off the mark,

you can also rev the motor higher in a tank in gear than you should on muffs in neutral

 

[sberl]

Thanks for the info guys. I don't have a service/repair manual to verify the part number but that is the one I found as well jbuote. Do you think this is something a newb could do? I've never worked on a lower unit before and just minor repairs on motors in general. I don't want to spend ~$90 only to find out it's beyond my skill set.

 

[jbuote]

I only got into boating 2 years ago.
It's one of the first things I did too..

With some tools you absolutely CAN do it.
I would suggest you find a factory manual for your engine. That's one of the first things I got as well, and it was worth it.
I have Johnson engines, but I think you can find some for Mercury here:
http://boatinfo.no/lib/library.html#

The Mercury folks here can tell you if these are factory or not. I don't know. lol

Don't be afraid of asking more questions either. the gurus here really do enjoy helping out. Especially when someone is actually learning something!
So asking questions as you work on it is no problem! Even better with a pic of what you're asking about.

So yes.. I have no doubt that you can do it.

 

[sberl]

Well thanks for that vote of confidence haha. I've been trying to locate a service manual but am not even sure if I can find the right one of those. The engine S/N is A951776 and the PO has written on the installation manual "Model #1035 N" (or maybe "W"). I searched the boatinfo link for the manual but don't think it has one for my 1987.

I assume the 2 nuts/bolts (one on each side) circled in the pic below are all that is needed to remove the entire lower unit?

 

[jbuote]

Well the Merc gurus can say better than I can, but I looked a little more, and while it's a bit more generic, this claims to be for 1965 - 1989, 2 - 40hp engines.
The link is right to chapter 9 "Lower Unit".
http://boatinfo.no/lib/mercury/manuals/mercury_1965-1989_2-40.html#/282

That chapter covers a few different lowers, but you should be able to figure out if you have "A", "B" etc..
Then find that section for "B" (I think would be yours, but don't count on it! LOL)
Probably not the best manual, but could be a start...
Hope it helps!

 

[sberl]

That link does get me closer - thanks!
Well I started removing the nuts but am stuck right now. I've loosened these 2:


Found another after I raised the motor:


My question now is, do I need to remove this trim tab bolt (and the trim tab itself) to remove the LU?


Also, maybe a dumb question but can I expect any oil to spill out when I get this to drop? I'm just not sure what to expect lol.

 

[jbuote]

Again, my experience is with Johnson engines, but most are similar...

On mine, yes. I have to remove that trim tab and bolt to get the lower off.
No, gear oil should not spill out when you get it to drop. Lower unit is sealed.

 

[sberl]

Removed it and found another bolt hidden under it. I now have the LU removed. Time to order the kit, it will be my first order from iboats and I don't know what the promo code is for members. Any idea?

 

[jbuote]

Forums5

For some reason, all caps wasn't working.
I don't think it matters, but forums5 (in all caps) is what's displayed on the right side of the main forums page.. LOL

Glad you got if off! Making good progress!!

 

[sberl]

Thanks, I couldn't get it to take it so I just continued on without. I really appreciate the guidance on this!
Steve

 

[sberl]

Maybe caps does make a difference haha. I'll have to try that next time LOL. Thanks again.

 

[jbuote]

Ok..... Maybe it DOES make a difference! haha!!
Hmm..

Anyway,
No problem!!
I've gotten a bunch of help here over the last 2 years, so if I can provide some that's great!
Kind of giving it back. :joyous:

Still pretty new in the grand scheme, so it's ALMOST like the blind leading the blind, but not quite... ound:

Don't worry though...
If I get too far off track, I have no doubt the gurus will step in, and provide proper guidance!

 

[sberl]

I know the feeling, I've gotten quite a bit of help here over the past year. Just don't have much to offer back yet but do give input when I can.

Anyway, good call on the impeller ...

 

[jbuote]

OH YEAH.....
That's toast!! :faint:

Yup! you made a good call on the impeller. It was your thought, and some thoughts from mbhoag

All I did, was help you get to it! LOL!!

Might want to do a backflush if you can to rinse any pieces that may have gone up the water tube out.
Not sure how easy it is or isn't on yours.

Maybe a guru will advise on if you really need to, and if so, the best way to do it on your engine.
Something I'd consider doing though. Don't want any pieces causing a blockage in the cooling system.

 

[sberl]

Flush makes sense. I’ll have to research to see how it’s done.
Im not sure this project will ever end lol.

 

[mbhoag]

Yup! you made a good call on the impeller. It was your thought, and some thoughts from mbhoag

Quick... I gotta run and tell my wife I actually did have a good idea this year!:laugh: