Penta MD11C Heat exchanger T pipe disaster

StefanSG

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Overhauling my MD11C and stupidly tried to remove this T piece for cleaning. It snapped off. Any ideas what I could replace it with ? Not sure if bronze or brass but seems to have dezincified. It could possibly be bypassed I suppose - it sits under the middle of the heat exchanger and returns seawater to the thermostat and onwards to exhaust elbow. Connecting two 16mm ID hoses. Volvo part 833356 no longer available everywhere I looked !

StefanSG
 
Overhauling my MD11C and stupidly tried to remove this T piece for cleaning. It snapped off. Any ideas what I could replace it with ? Not sure if bronze or brass but seems to have dezincified. It could possibly be bypassed I suppose - it sits under the middle of the heat exchanger and returns seawater to the thermostat and onwards to exhaust elbow. Connecting two 16mm ID hoses. Volvo part 833356 no longer available everywhere I looked !

StefanSG

Thanks, it's seawater cooled. These are standard parts.

SSG
If it has dezincified it is brass , not bronze. Bronze does not dezincify because it contains no zinc. It is an alloy of copper and tin.

You cannot bypass it because it is the cooling water inlet , via the exhaust manifold, to the two cylinder heads. You will have to make something to replace it.

While you are there be aware that one of the problems with the MD11C is that the channels from the tee piece to the two cylinder heads become blocked over time.

There is no heat exchanger in a directly seawater cooled engine
 
There is no heat exchanger in a directly seawater cooled engine
I thought I attached a picture, apologies.

IMG_4215.jpg

Hi Vic, it is from the bottom of the exhaust manifold, the manifold connects directly to the cylinder heads via the channels at the bottom of the picture. I just realised, you're correct, this t is for the inlet hose that also runs to the thermostat housing, so pretty vital !

regards

SSG
 
Last edited:
I thought I attached a picture, apologies.

View attachment 129977

Hi Vic, it is from the bottom of the exhaust manifold, the manifold connects directly to the cylinder heads via the channels at the bottom of the picture. This t is for a return hose that runs backwards to the thermostat housing.

regards

SSG
You do not understand the water flow

Water from the pump enters the channels in the manifold via this tee piece flowing to the two heads . Water also continues from the other branch to the thermostat bypass
Hot water leaves via other channels in the manifold and the thermostat, combining with the bypass flow and then to the exhaust elbow.
 
You do not understand the water flow

Water from the pump enters the channels in the manifold via this tee piece flowing to the two heads . Water also continues from the other branch to the thermostat bypass
Hot water leaves via other channels in the manifold and the thermostat, combining with the bypass flow and then to the exhaust elbow.

Apologies Vic, I was in the middle of replying to you, and editing my original message, you are of course correct, I hadnt got my head around the plumbing.

SSG
 
I suspect that the thread is 3/8 bsp but do check first which would allow you to fabricate a replacement the parts are probably available from ASAP or similar suppliers
 
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