Time for a new motor?

[thegipper]

Quick little history of the 1970 60hp johnson in question.

Recently it's been having some trouble starting and staying idling. At the same time, I noticed the pee hole (I added) does not have a steady stream of water coming out. The pee hole sputters and doesn't have a constant flow.

Last friday when I had the boat out, it started fine initially but when I went to start it later in the day again, it struggled to start again. Eventually I got it started and was going slow to the other end of the lake (slow no wake). I looked back and noticed the pee hole wasn't spitting water again, almost at the same time I looked down and the hot light came on. I immediately shut it down.

Took it back home and decided I was going to try to flush the system out. I hooked up my ears to the water intake and flushed it for a good 10 minutes. Unfortunately, no water comes out the pee hole when I'm doing this?? I then back flushed the system through the fitting on top of the cylinder where I added the pee hole. Water comes out the intake on the lower unit which I'm assuming is normal. I'm thinking there is some kind of blockage in the water tube? I also removed the thermostat while I had the ears hooked up and water isn't even making it up to the thermostat housing??

When I bought the boat I checked the cylinders, 120,110, 120. Not great but not terrible. Motor always fired up on the first crank and idled/ran excellent. On my 16' starcraft, boat did 31mph with two big guys in it which seemed good to me (hull is rated for a 90hp).

My plan was to drop the lower unit and see what is going on. Before I did that, I decided I should check the cylinders again. Well, with my push on compression gauge, 100, 50, 75.....What the heck happened?? Is it worth trying to decarb it?

So at this point, do I even bother trying to fix this motor? What is so frustrating is this motor worked absolutely flawlessly when I bought it. I've only used it maybe 7 or 8 times. Previous owner had the carbs rebuilt/synced, new impeller and a couple other things just a year ago. I just put a new rectifier and starter solenoid in it.

Thanks for any help/advise you can give.

 

[racerone]

Remove cylinder head for inspection.-------My compression tester shows 140 psi on these in good condition.

 

[thegipper]

I can certainly do that. I forgot to add, I used my inspection camera to take a look inside the cylinders. It didn't look good, I saw a few vertical lines of scratches on the cylinder walls. If the cylinder walls are all scratched up, is that the death blow?

 

[ondarvr]

I can certainly do that. I forgot to add, I used my inspection camera to take a look inside the cylinders. It didn't look good, I saw a few vertical lines of scratches on the cylinder walls. If the cylinder walls are all scratched up, is that the death blow?

It all depends on how deep they are, and if you want to rebuild it.

​As mentioned, pull the head off and see what it looks like. A blown head gasket can stop water flow, but typically only when it's running, continuing to run it in this condition can do the kind of damage you saw on the camera. When the head gasket starts to leak the exhaust can leak into the water jacket and over power the water pump, this can stop water flow and cause the spitting you saw in the pee stream.

 

[Crosbyman]

previous owner did the impeller how many..... "few years" ago ??

flushing the cooling system won't fix a bad impeller better check the impeller and get it to pee correctly ...

​" My plan was to drop the lower unit and see what is going on" ...good plan !

why not retest comp with a good or different meter as a reference point

tried doing a decarb??

scratches not good but it ain't dead yet anyway !

 

[thegipper]

The impeller was replaced about 2 years ago. I tried using a different compression tester (screw in type) but I think something is messed up on it, I borrowed it from a friend. It measured 60, 15, 25 which doesn't seem right at all.

Is there anything special to taking the head off? Just undo the bolts and pull it off? Thanks so far!

 

[racerone]

Remove bolts and it falls off.----Just a 1/2 ' socket and about 20 bolts.------Outboard motors are really well built.---Rarely wear out.----They end up on the scrap heap because somebody made a mistake !!

 

[thegipper]

Ok I'll pull the head off after work and take a bunch of pictures and report back.

 

[thegipper]

Almost forgot, is my theory that the water tube is plugged a good one since when I hook up the ears, no water is getting up into the engine?

 

[thegipper]

One other thing, I did some research and some people said that intermittent pee stream can be cause by an exhaust leak into the water jacket. That still wouldn't explain why when I hook up the ears while it is not running, I'm not getting any water out of the tell tale and I can't see any water in the water jacket when looking through the thermostat housing.

 

[ondarvr]

That's why you take it apart, so you can find this out.

 

[thegipper]

I did just that after work. I have to resize the pictures which I'll post in a little bit here.

The head gasket was totally messed up, especially on cylinder #2 and #3 which is where I was getting the low compression numbers. I also found out why I'm getting oil the in LU, there was milky LU fluid all over the impeller, housing and drive shaft. The drive shaft seals must be totally shot. I'll give more details once I get the pictures shrunk.

 

[thegipper]

No Title

Here is the head gasket, between #2 and #3 it has totally failed. The metal ring around the #2 cylinder is literally split in half.



Cylinders pictures are below. None of the "marks" are deep, most just feel rough but none catch your finger nail. Can the cylinder walls be honed or should they be left alone? Or is some other method I should use to clean them up? Or is it not even worth it?

I also found out why my LU is getting water in it. The seals on the drive shaft must have gone bad. There was watery LU oil in the impeller housing, the bottom plate and the seal/bearing housing. I'm also not sure if the plastic water tube is good still, it has notches/groves in the top of it. The impeller itself looks fine and the housing appears to be ok? Anything else out of the ordinary on the impeller/housing?

I also found on ebay a new bearing/seal assembly for 38 bucks. The drive shaft has about 1mm of play in it. Is that a bad thing? Or should I just buy the whole new seal/bearing assembly or just buy new seals?

Also, there was a o ring that was in the middle of the drive shaft when I removed the LU. Where is this O ring supposed to sit? It definitely needs to be replaced.

 

[thegipper]

No Title

Here is a video of cylinder walls and some pictures.

https://www.youtube.com/watch?v=TykGo0KQk0w

 

[thegipper]

No Title

Here are the pictures I took of the impeller and other stuff.

 

[thegipper]

If you have any questions or need a better picture of something, please let me know. I am really hoping I can save this motor!

 

[thegipper]

No Title

The bottom impeller plate has a grove in it by the ID where the drive shaft goes through. I'm assuming that grove isn't supposed to be there?



Also, the impeller housing has a grove in it by the ID. It doesn't look the best either and I think the housing is pretty expensive which sucks.





Also, I still have no idea why the water was not going up to the cylinder head when I had the ears hooked up, even when it wasn't running. I still cannot understand why it wouldn't be going up under the pressure of the hose?

 

[thegipper]

I was thinking replace the head gasket before I even mess with the LU. If the compression after the new head gasket is bad, there is no point in trying to fix the LU leak/water flow issue right? Is there something I should do to the cylinder walls, again no grooves bad enough to catch your finger nail on but some areas looks like they got funky from where the head gasket failed.

Oh and none of the rings are broken so that's good.

 

[oldboat1]

Like you suggest, I think I would try a new head gasket and see if compression improves -- need a dependable screw-in type tester. Your head cover looks like it needs some work -- can't tell for sure in a pic, but look for chips or any damage around water passages. Also, looks like there might be a blockage down under the bottom cylinder. The gasket is holed, although that might be from removal. The fresh one may or may not require some gasket sealer (may tell you on the gasket to apply dry).

I would really clean up the head cover with some carb spray, maybe consider some soaking. Take off all gasket traces with a putty knife, and when dry resurface the mating surface -- done on a hard surface (some use a piece of glass) and 400 grit wet/dry sandpaper. figure 8s until the shine is the same on all surfaces. The t.stat cover should get similar treatment before getting a new gasket for that cover as well.

As an aside, I wonder if your tell-tale installation is good. Your motor is about 10 years older than the ones covered in the service bulletin re. moving tell-tales, and I know that location was in a similar location to yours (moved in the affected motors from the bottom). But I think you might want to pull off the exhaust cover and see if there some blockages in there, or consider drilling a hole in the top of your head cover while its off and you can see exactly where the water jacket is -- tell tale might work better from that location.

Your impeller and water pump assemblies don't look too bad, although I would resurface the wear plate like the head cover above, then use a fresh impeller while in there. After that, I would reassemble it and pressure test (drain oil). Can rig a bike pump to give it 6 or 8 lbs -- do it in a tube of water and watch for bubbles to tell you if there are leaks and where they are located.

When you get the head put back together, I would push some water up the water tube and see what circulation you get. You can also check the water pump operation while the l.u. is off -- dunk it in a tub and turn the shaft clockwise with a half inch drill.

 

[thegipper]

Thank you for the feedback oldboat, hopefully others will chime in too.

I will clean up the head and the head cover as suggested. I'll get a new head gasket ordered and get the head put back together. I think it will be pointless to work on the LU if the compression is still bad after the head repair. I ordered a new screw in compression tester which will be here tomorrow.

I don't think I can test the water pump operation as you described since the impeller is powered by the drive shaft (bigger than half inch).

What do you think of the cylinder walls? I think the pictures look worse than they actually are. Should I do anything to the walls or just put the new gasket on test compression again?

Thanks again