exaust elbow question

[adru]

I purchased and recieved new OSCO exaust elbows for my 1999 volvo penta 5.0 gi DP engine but noticed after I recieved them that they do not have the removable plugs on the side towards the bottom of the elbow that the original volvo exaust elbows have. On the original port side volvo exaust elbow there is a 3/4" hose attached to a small threaded elbow fitting inserted into only the port side exaust elbow. I don't know where this 3/4" hose ends as it goes down behind the rear of the engine (what is it for?). Do I have to have a hole drilled and tapped into the exaust elbow, should I ask can I do this in a cast iron elbow (I can reuse this small elbow fitting and I'm assuming the small elbow fitting with the hose attached is tapered to seal the fitting when threaded into the exaust elbow?) or do I have to return the osco elbows and purchase at much greater expense original volvo replacement exaust elbows from the volvo penta website (I see original volvo penta exaust elbows have several plugs in different locations).
Thank you

 

[Scaaty]

Re: exaust elbow question

Some pictures here would help. Seems you might want to go with what Volvo wants..you might have ordered a wrong elbow too, but even here what you and I call an 'elbow" might be two different things. Most compose of manifold, riser, and then sometimes into an elbow, which connects to the Y pipe or exhaust. Maybe others here will be along to help...don't give up yet.

 

[Don S]

Re: exaust elbow question

I'm assuming that 3/4" hose you are refering to is actually 3/4" outside diameter, not 3/4" inside. If so, it's probably the 3/8" ID hose that goes from the Vapor seperator tank (VST) to the exhaust manifold. That is where the cooling water exits the VST. It has to be there, and it goes into the water jacket of the riser, not the exhaust side.
I would suggest you get the correct Volvo riser.

 

[adru]

Re: exaust elbow question

Don, you are correct that the hose is 3/4" OD and from what I can see probably 3/8" ID. The small elbow fitting is attached to the lower part of the port exaust riser (there is no similar hose comming from the starboard riser). I will order the correct part on monday but I can't seem to find an aftermarket product that matches which means I'll have to purchase the Genuine Volvo Part which means +$. Thanks for the info.
By the way what is the purpose of the VST and how does it relate to the cooling water through the riser jacket?
1999 5.0 Volvo Penta Gi PWTR DP

 

[bruceb58]

Re: exaust elbow question

I always buy the Volvo risers anyway. Google on Fast Eddies marine. They give 18% discount and they get drop shipped from Volvo.