'96 Johnson 60 HP,Low-oil, motor seized, now knocks and rattles

[Tagged]

Locked up my motor by running it out of oil, stupid mistake I know. Cooled it off, pulled the plugs and oiled the cylinders, turned it over manually, and then restarted. I got very lucky. The motor still starts right up, still gets to max RPM with a full load.

The motor has a knock or rattle at all speeds. It's a twenty year old motor, and part of me says just run it. Surely I shortened its lifespan, but I didn't kill it.

But another part of me says it should be fixed. And that part is winning. I don't know what is likely to be wrong with it, or how much of a rebuild I'm looking at.

What needs fixing?

Tag

 

[Faztbullet]

Skirts on pistons are scuffed and cylinders scored, the noise is piston slap. Keep running it and that other part of you will be kicking you when it fails.

 

[Tagged]

How do I fix that? Hone the cylinder walls?

 

[racerone]

You tear the motor down.---Then inspect the parts.----Likely send it to the machine shop for boring / honing.--------Then firt 3 O/S pistons and rings.---Inspect and repair the alarms on the motor too !!!!!

 

[Tagged]

Ok, I'm comfortable doing all of that work myself, except for the honing/boring. So sending it to a machine shop at that point is fine with me. What should I expect to be charged?

What about the oversized pistons and rings, where do I get those? How much will I pay?

Tag

 

[racerone]

Look up all your parts on ----shop.evi***de.com---Be about $450 / 500 on parts.----Inspect lower unit and water pump too

 

[Bosunsmate]

Ok, I'm comfortable doing all of that work myself, except for the honing/boring. So sending it to a machine shop at that point is fine with me. What should I expect to be charged?

What about the oversized pistons and rings, where do I get those? How much will I pay?

Tag

Depends how many need boring, i find its about $80-$100 a cylinder. You can buyer a honer for $25 and do that yourself

 

[Tagged]

OK, two questions.

Does that honer Chuck into a hand drill? Ive seen those. May even have access to one.

Why is it called piston slap? What's slapping against what? I thought piston slap was when the piston slapped the head, but honing sure wouldn't help that.

 

[schematic]

If you consider doing it yourself, best be getting a "rigid hone". The $25 variety is only good for deglazing....

 

[gm280]

Tagged, I read all the comments and think I understand what you're asking. If you seriously like your engine and want to rebuild it back to a quality power plant again, remove the head and see what everything looks like as the piston tops and cylinder walls. If you have obvious wear and think you may need new pistons and rings, take it to a competed machine shop for them to measure the cylinders to verify a few things. First, see if the cylinders are workable with either over-boring or just honing. Second see if the cylinders are still round instead of egg shaped, and thirdly, if it does need over-boring, how much they can cut so you have an idea what oversize piston and rings to procure. And if that seems like a doable situation, then you have to disassembly the entire block and everything for the machine shop to work. And at that time you also can see the connecting rods and crank and bearings to see if those items are usable as well. Once you know all the damage and think you do want to rebuild, let the machine shop do the precision boring and honing. That IS what they do best. And then you will have total confidence in a great running engine again as well... If you don't presently have a manufacturer's year, HP, and model specific shop manual, buy one and read it. There is no better info available for your engine then the manufacturer's shop manual. Don't buy an after market manual. They are too general to go into every little thing about your engine... :thumb:

 

[WernerF]

Just curious, did You forget to mix oil or did the VRO system?

 

[Tagged]

It has VRO, but I can't blame that. The alarm didn't work, and I let it run out of oil. VRO can't pump oil if there's no oil to pump.

I do like the engine, and have no money to replace it. So I need to do the work.

 

[Tagged]

Updating a very old thread, in case someone pulls this thread up in a search and wants to know the results. I never fixed the engine. It ran for a year. The knocking sound never went away, and the engine never lost power. Until, suddenly it did.

Almost exaclty one year after this low oil incident, the motor overheated cylinder #1, melted a piston, and locked up. You can read about it here:

https://forums.iboats.com/forum/eng...outboards/10270116-johnson-60-blown-powerhead

I might have been able to prevent the overheat by rebuilding after the low-oil incident, or the two things might have been unrelated. I never found out.

But the bolts holding that motor together were severely corroded from 20 years in salt water. I eventually gave up on my rebuild effort and bought another old motor. I'm currently resurrecting an old Johnson 140, you can follow that thread here:

https://forums.iboats.com/forum/eng...ds/10527841-tagged’s-140-johnson-resurrection.