90 model 4.3 omc cobra getting hot

[whitehairdude]

Just started this weekend, gauge starts climbing to 240+ while shut down. Cools to 120-140ish while on plane or fast idle. Will get hot while idling in gear (no wake ) !!! Impeller ya think? Seems to me if the impeller is going out wouldn't it just get hot and stay there? New boat to me so I have no idea how it's been taking care of!

 

[HT32BSX115]

Re: 90 model 4.3 omc cobra getting hot

Just started this weekend, gauge starts climbing to 240+ while shut down. Cools to 120-140ish while on plane or fast idle. Will get hot while idling in gear (no wake ) !!! Impeller ya think? Seems to me if the impeller is going out wouldn't it just get hot and stay there? New boat to me so I have no idea how it's been taking care of!

Replace the impeller. and ensure that the raw water supply hoses, power steering and/or oil coolers are not plugged with the impeller fragments or other debris.

I wouldn't even put a "new" boat in the water without FIRST replacing the impeller and checking the raw water circuit!!


Regards,


Rick

 

[whitehairdude]

Re: 90 model 4.3 omc cobra getting hot

I hear ya, I've never owned an omc/ cobra outdrive ! The guy at the boat shop says it real easy to replace, don't have to drop the lower unit??? (I gotta see this ) I haven't found an impeller in a diagram yet to see where it's at on the darn thing!

 

[lasko1]

Re: 90 model 4.3 omc cobra getting hot

Super EASY to replace the impellar and don't have to remove lower unit. I just did mine.

1- Remove the (3) 3/8" bolts from the curved cover on the lower unit. You will see the impellar housing with a rubber tube connected to it.
2- Remove the (3) 3/8" bolts from the housing and take it off. The rubber impellar will be inside it in a stainlees steel basket.
3- If the impellar got hot, it could have melted the stainless basket into the plastic housing. If so, just buy the water impellar kit for ~$50. It comes with the impellar, stainless basket, rubber o-ring, plastic housing, metal backing plate and the gasket for it.
4- You'll need some type of lube or gasket adhesive to hold the o-ring in place while bolting up the impellar housing

If the impellar didn't get hot and do any melting/damage to the stainless basket, you can get by with just replacing the rubber impellar for about $25.