What to do after impeller meltdown?

sly_karma

sly_karma

Crew Member
I goofed up and ran my E-tec 130 at the shop without water to the earmuffs for a minute or two. Fried a new impeller and the pump housing. Lots of black rubber residue inside on the walls of the housing. I'll fit a new pump today, but I'm wondering about rubber particles elsewhere in the cooling system now. Any recommendations for flushing? I thought maybe remove t-stats and blast in through there, plus up into the pump delivery tube before I reinstall the gearcase. Anything else?

Looking at the impeller, although it's obviously shot, there's no major chunks of it missing either. Any debris that it shed would be pretty small particles.

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Nice work


If any piece went through, it could block the thermostat, or the cooling line for the fuel and EMM. Doesnt look like alot of material come off.
 
Yeah good point, I better pull off the EMM and VST water lines and blow them out.
 
The water line comes out of the block, goes through the VST, and then goes through the emm and then dumps out the back. The water you see coming out of the back of the inline engines and the 60 degree engines is the cooling water path I explained.

Big stuff can get caught in there. Little stuff will only get caught in the tstats
 
Yeah I did. Was in and out of boat, stopping and starting motor, shutting off water between runs to avoid driveway erosion, etc etc. Can only think in all the back and forth trying to diagnose a cylinder miss that I ran it without water. It was cooling fine when I first got it.
 
I had one recently that granulated fairly small pieces. Ended up blocking the upper water tube. However that was a merc. Smaller water tube. Its happens that's for sure.
 
This is not helpful advice or anything...but I just finished replacing the water pump assembly on a '79 Johnson 20 and it's crazy how nearly identical they are, despite being separated by three decades and a hundred horsepower.

Anyway I agree that the big question here is: did you turn on the water? Or just shut the engine down? If you turned on the water I'd probably go flushing out passages; if you just shut it off, I wouldn't bother. Nothing to distribute bits of rubber and plastic if the water wasn't on.
 
sly_karma said:
Yeah good point, I better pull off the EMM and VST water lines and blow them out.
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not sure when you say blast em out if you are using water or an air compressor.
air works great for blasting out bits.
 
I think water was probably run after the dry run. I was stopping and starting constantly. I don't definitively remember running it without water but it's the only thing that makes sense.

Anyway I gave it a good blow out with air from t-stat ports and water pump delivery tube. Now to reinstall gearcase and run it on the muffs again. I installed a shutoff valve fitting into an extra length of hose and hooked it onto the gunwale close to the helm control so now I can start and stop water and motor conveniently from inside or outside the boat.
 
I ran the motor this afternoon and all went well. It came up to temp and stabilised as the stats opened. I had an injector repaired recently so I was watching carefully with infrared gun to see if there was a temp difference between cylinders in same bank that could indicate one running lean. All appeared to be normal. Did a de-carbon treatment using Engine Tuner spray. Good thing I didn't do this back in August or an air tanker might have dropped a load of retardant on me, there was that much smoke.

Motor is now 'soaking' with the Engine Tuner, tomorrow I'll take it to the lake for another smoke session and then run it up while tied to the dock to see if anything untoward happens with that injector. If all is well then I can finally take it for a water test. Moving from tired late 80s Merc 150 to modern 130 should deliver a big load of torque and top end speed.
 
sly_karma said:
Diameter sufficient for lower unit of midsize outboard? Drain valve is a good idea. I'll check at Growers Supply, they usually have empty barrels from products they sell by the litre, like dormant oil.
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My motor is only 50hp so I don't know. I slide it on and then tilt down and fill, then empty with the tap. I've spent a few weeks running it every few days with new plugs, a heavy mix of Seafoam, and a good dose of SaltAway trying to chase an overheat issue, which makes the barrel handy. It ran good on Friday up at White Lake. Only one trout on a cold wet day.
 
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I'll measure mine and check it out further. Would be nice to run inside the shop rather than towing outside the door. I've got a big butt exhaust fan mounted that would deal with exhaust fumes. Not to mention two strokes run differently on muffs since there's no exhaust back pressure. This motor has 1100-odd hours on it so a thorough salt away treatment would make a lot of sense, other projects to chase as well like replacing all the internal fuel hoses.

It occurs to me that whatever drain fitting I use on the barrel should have a hose connection so I can drain it outside the shop; slab is level and there's no floor drain. I don't think there's enough height available to put the barrel on a pallet and remove it with a pallet jack.
 
My barrel is 22" diameter. Motor is 20" from front to back at the cavitation plate. So a bigger motor may be tight.
 
Who did your injector replacement?

You will never know when a cylinder is running lean. It will be at high speed anyway
 
I did the troubleshooting to identify the injector problem, and then the removal/replacement. Two Evinrude dealerships directed me to Precisionline Fuel Injectors for that specialist work.

I have a good quality IR gun, using that to look for temp differences between the two cylinders in the bank, allowing for the lower of the two gets the supply water first so will run slightly cooler.

The injector in question happens to be right beside the temp sender so I should be able to monitor it out on the water.
 
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