Problem with Bypass Valve TAMD 61A

[crawfordalexander]

Hi

I may or may or may not have a problem with a bypass valve.
I have been plagued with an engine not responding to load,reduced rpm and very smokey.
After trying numerous things -I found that there is no air being diverted into the aftercooler.
On removing the bypass valve it seems to perform much better with no smoke.
Is there serviceable parts for this and if so what could be the problem - i've looked at the diaphram and it looks fine.
I'm struggling to see what really could be wrong with it.
Is there something else i may be overlooking that may cause the valve to not function properly?

I really am perplexed at this but i would like to get the boat back in operation.
All injectors have been re-conditioned but didnt make any diofference

Hoping someone can help out
Thanks

crawford alexander

 

[rosssavage]

Crawford, yes, all the parts of the bypass valve are available. A VP dealer can source for you - clicky: http://www.volvopentashop.com/DBMar...es/7746650/7746650_25/7746650_043/7746650_045

Do you have a twin engined boat? If so, swap the valves over and see if the fault clears.

How did you manage to run the engine with the valve removed?

 

[crawfordalexander]

Swapping them over was an option -however we already know the other one is fine and didn't really want to disturb the other engine too much - temperamental as they can be
I'm sure my friend made a plate to block something off -probably with the valve in place - i'll find out in more detail and update you.

What i am unsure about is why this may not be working properly- and whether the fault is indeed with the valve or something else contributing to it not working properly-inadequate pressure? I'm not convinced as the valve itself looks physically ok...

 

[volvopaul]

Swapping them over was an option -however we already know the other one is fine and didn't really want to disturb the other engine too much - temperamental as they can be
I'm sure my friend made a plate to block something off -probably with the valve in place - i'll find out in more detail and update you.

What i am unsure about is why this may not be working properly- and whether the fault is indeed with the valve or something else contributing to it not working properly-inadequate pressure? I'm not convinced as the valve itself looks physically ok...

Can you tell me what make and model of boat.

I'm guessing here its the starboard engine? Have you done a boost pressure test on sea trial on both engines?

Problems are solved by collecting data.

An old age problem now with the 61 and 71/72 series engine with low power output is rotten intercooler housings, the alloy part rots away then the boost is dumped in the engine room, have you had the intercooler off for service, ie strip clean, bth waterways and air side to clean the build up of oil on the fins.

Is the turbo 100% good condition, have you checked the inlet and exhaust side on each rotor?

61 A is a very simple engine so it can't be much.

I take it you have done the basics like fuel supply etc, high idle test should be a shade over 3000 rpm.

Come back to us with what I've asked.