exzuast leaking out of top of lower unit?

[Rdepaoli1]

Ok so I noticed todat that at idle I have exzuast bubbling, heavy out of the top of my lower unit, when i put it in gear, the majority comes out of the prop but there is still a constant bubbling out of the outdrive. as i posted in a previous thread I'am having a strange high rpm over heating issue, I think the leak might be blowing exzuast into the waterpump housing during higher rpms? I'am not to happy with the mechanic i hiered to do the water pump & really think the rubber exzuast gasket shifted. I'am sure exzuast should not be comming out of that seam. Should it be bubbling out of there or am i pulling straws? I circled the leak area in the pic below.

 

[Chris1956]

Re: exzuast leaking out of top of lower unit?

I think you are fine. A lot of those seams between the gearcase and the midsection have spacers built into the casting to allow cooling water (and exhaust) to escape. See if your seem has the raised portions on the loip of the gearcase. You may have a bad exhaust gasket, but that is a minor issue.

What motor is that? What year?

 

[emdsapmgr]

Re: exzuast leaking out of top of lower unit?

If you recently had the lower unit off the engine, you could have a problem with the alignment of the rubber seal/exhaust gasket 320961 that fits between the lower unit and the midsection. That oring keeps the exhaust channeled down into the lower unit. It often swells and may not fit properly when the lower unit is reinstalled after water pump changeout. If it swells, that gasket won't seat properly and you can get stray exhaust from around that oring. That may be where the bubbling comes from. Worse, the exhaust heat can have a negative affect on the nearby plastic water pump housing and cause it to deform over time.

 

[yoster]

Re: exzuast leaking out of top of lower unit?

Isn't that an OMC I/O lower unit?

 

[Rdepaoli1]

Re: exzuast leaking out of top of lower unit?

its a 200 out board, 83 crossflow