Volvo Pentax overheating

Rocksteadee

Rocksteadee

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Volvo Penta overheating

I have a Fairline Turbo 36 fitted with Volvo TAMD61a engines and have one over heating over 1800 RPM
Tests and jobs done so far.....

All 3 heat exchangers removed and de scaled

New impeller and wear plate and cover

Thermostat tested against a known good one (open before good one and fully open before and wider than good one) it was marked at 75 deg

Calorifier circuit isolated

New antifreeze

At 2100 rpm temp creeps up and temp alarm sounds at about 95 deg on gauge so have assumed gauge read ok.. Other engine alarm sound at about same temp before I had the heat exchanges done so have assumed sensor setting about the same
Other engine now runs a constant 82

Is it possible that the engine can generate more heat then the exchanger can cope with
Are there any 'known' problems to cause this as I cannot even run at high enough revs to keep the turbos spinning

Perhaps I could call her a Fairline 36

Any response greatly appreciated
 
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Cannot speak for your problem but have come across in the past, a partially closed inlet sea cock caused by old age, and rubber connections in the supply side partially closing due to the suction and again old age. Also are intakes/filters clear? Can you see the exhaust water? are they both about the same amount.
 
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Rocksteadee said:
I have a Fairline Turbo 36 fitted with Volvo TAMD61a engines and have one over heating over 1800 RPM
Tests and jobs done so far.....

All 3 heat exchangers removed and de scaled

New impeller and wear plate and cover

Thermostat tested against a known good one (open before good one and fully open before and wider than good one) it was marked at 75 deg

Calorifier circuit isolated

New antifreeze

At 2100 rpm temp creeps up and temp alarm sounds at about 95 deg on gauge so have assumed gauge read ok.. Other engine alarm sound at about same temp before I had the heat exchanges done so have assumed sensor setting about the same
Other engine now runs a constant 82

Is it possible that the engine can generate more heat then the exchanger can cope with
Are there any 'known' problems to cause this as I cannot even run at high enough revs to keep the turbos spinning

Perhaps I could call her a Fairline 36

Any response greatly appreciated
Click to expand...

Right, I've been through he same many times.

See everyone starts at the inlet side thinking its pump, impellers, coolers, gear cooler. Did is on my own boat and a sedan 36 of late. Turned out to be the exhaust elbow that was partially blocked, remove it and look up the inside , you will see the inner dry part, between that and the outer is the water spray jacket you will see tag tike metal strips, all the gaps must be clear.

A tech way of course is to fit a pressure gauge inline from the sea water pump, you should see no more than 3/5 psi at wot.

You can also use a heat gun and measure the raw water temp on the last pipe out the intercooler is best place for a reading, you may find its quite high which means the water flow is stalling . On my just sold boat I fitted a clear hose from the gear cooler to the elbow, that way I can see if there are any air bubbles in the system and the actual speed of the flow.

I spent a while doing all you have done just because I saw above 85deg c at wot, a wasn't happy as these motors do run cool when the right.

Last thing, did you remove the heat exchanger stack from its housing and pressure wash it as it does clog up with rusty deposits and sludge from the engine internals.

One other last thing is there water flow from the circulation pump as the impellers do fall off.

Keep us posted , I bet its one of these items listed.

Are you doing this work yourself or have you employed a pro? I'm south coast if oh need any further help.
 
omega2 said:
Cannot speak for your problem but have come across in the past, a partially closed inlet sea cock caused by old age, and rubber connections in the supply side partially closing due to the suction and again old age. Also are intakes/filters clear? Can you see the exhaust water? are they both about the same amount.
Click to expand...

Omega
Sea cock open. Strainer clear. Pipe from strainer is not original as it is exhaust pipe so feasible inner wall could have collapsed.
Easy enough to look at so on list
Cheers
 
I have a pair of 63p's 12 years old, we Rydlymed both engines this year and later following a failed exhaust riser we took the water injection elbows off and they were 75% blocked with corrosion and general crud, these have been replaced on both engines.

If you have gratings over the seawater intakes the ones like a dome with slices in them these get antifouled each year and its surprising how the paint restricts the water flow its worth scraping these out each time as well as checking your valves.
 
Cheers Paul. Was hoping you we're gong to pop up
I did wonder about back pressure as on removing each of the heat exchanger raw water drains and then shaft seal feed pipe, there seems to be too high a pressure just on tick over
At 2100 sea water feed from pump is cold. After 1st exch it is Luke warm. So does not appear to be stalling?????

Engine cooling exchanger was removed striped and cleaned by ext company so did not see inside but I had rebuilt myself a year ago as was leaking
Jabsco Impeller is new or do you mean the engine water circle pump for fresh water. I did wonder about this as engine water in and out of exch are both too hot to hold hand on
Not tried exhaust elbow yet but has been replaced from original and would poss need the floor lifting

Am in Brixham tonight but on way back to hamble by the. Where are you on south coast? As my next port of call is (nearly) going to take some money throwing at it and I would rather you as have had some good advice from you on other of cations

Getting to the
 
Bandit
Made sure when anti fouled that slotted thru hull intakes were clear of paint
But not realising that cooling water enters exhaust elbow thru a spray bar. This could be the problem
 
Rocksteadee said:
Cheers Paul. Was hoping you we're gong to pop up
I did wonder about back pressure as on removing each of the heat exchanger raw water drains and then shaft seal feed pipe, there seems to be too high a pressure just on tick over
At 2100 sea water feed from pump is cold. After 1st exch it is Luke warm. So does not appear to be stalling?????

Engine cooling exchanger was removed striped and cleaned by ext company so did not see inside but I had rebuilt myself a year ago as was leaking
Jabsco Impeller is new or do you mean the engine water circle pump for fresh water. I did wonder about this as engine water in and out of exch are both too hot to hold hand on
Not tried exhaust elbow yet but has been replaced from original and would poss need the floor lifting

Am in Brixham tonight but on way back to hamble by the. Where are you on south coast? As my next port of call is (nearly) going to take some money throwing at it and I would rather you as have had some good advice from you on other of cations

Getting to the
Click to expand...

On the hamble, swanwick marina.
 
I have recently changed the gear oil coolers on my Turbo 36. If you pull the carpet back right across the cabin with the engine hatches lifted you might be able to remove the floor panel across the cabin immediately in front of the access steps and steps down to the aft cabin. Mine was in one piece, so I have now cut it into two, where it rests on a beam to stbd side of the steps. Access to the 'difficult' end becomes a much much better, including the air filter, gearboxes and exhaust elbows.

Please note mine has the earlier TAMD60C, and I understand the main cabin floor on the later with TAMD61 was a bit higher to accommodate the later engines, but is shouldn't alter the general layout.

Please let us know what you find if you take the elbows off. You might be able to check the elbow jets through the water inlet port with an endoscope - Maplins for about £30-40.


Oh yes - could be you've got a camera stuck in the cooling system !
 
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superheat6k said:
I have recently changed the gear oil coolers on my Turbo 36. If you pull the carpet back right across the cabin with the engine hatches lifted you might be able to remove the floor panel across the cabin immediately in front of the access steps and steps down to the aft cabin. Mine was in one piece, so I have now cut it into two, where it rests on a beam to stbd side of the steps. Access to the 'difficult' end becomes a much much better, including the air filter, gearboxes and exhaust elbows.

Please note mine has the earlier TAMD60C, and I understand the main cabin floor on the later with TAMD61 was a bit higher to accommodate the later engines, but is shouldn't alter the general layout.

Please let us know what you find if you take the elbows off. You might be able to check the elbow jets through the water inlet port with an endoscope - Maplins for about £30-40.


Oh yes - could be you've got a camera stuck in the cooling system !
Click to expand...


Superheated
Would perchance be at the top of the hamble?
 
How's your trip apart from the overheat ?

When you get back I can show you where I cut the floor to gain the rear access. Let me know if you want to use my endoscope. Taking the exhaust elbows off isn't a task I would want to do without first at least trying to inspect for blockage.

Trevor
 
I'll be calling by sometime, so I will say hello. Don't want to suggest on here you show me yours and I'll show you mine, might raise too many unintended responses !
 
image.jpg

That should be an attached image of exhaust elbow. Threequarters blocked

Holes? What holes??

Ultrasonic and descale me thinks

Cheers guys, where would I be without you?

Oh yeah, doing 12 knots
 
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