TAMD74P coolant issue

[mlott]

Phantom 46 with two 1999 TAMD74P Volvos with around 1200hrs on each.

While motoring at about 80% throttle the other day, I had the Port engine overheat. On inspection, I found all the coolant in the bilge and not the engine! After allowing the engine to cool I refilled and the engine restarted fine. Raw water was flowing well, everything looked/sounded fine, but after a short while I notice it was gently expelling coolant down the overflow pipe from the filler cap. I shut it down again and carefully removed the filler cap, and fair amount of coolant was blown out, even though the engine was still well below working temp at this point. After topping up the coolant again, I ran it with the cap off, and discovered a constant stream of bubbles/gas from the coolant filler.

I assumed a blown head gasket, but on testing the gas for CO2, it can up negative, suggesting it's not a head gasket...

Anyone have any ideas where else air/gases could enter the coolant? or is the CO2 test not 100% proof.

No recent work on the engine (annual service due shortly). Oil looks fine. Raw water flowing well. It starts and runs fine at tickover and maneuvering about the marina (with the filler cap loose). Haven't tried it under load, as I didn't want to risk overheating again.

I found an old thread on here with a similar problem on a KAD32, but no info on if it was ever fixed. I very much hope someone can point in the right direction.

Not sure if this will work, but this is a link to a video of the bubbles:- New video by Martin Lott

Regards

Martin

 

[Portofino]

Sorry to hear about this .
How clean is the stern gear ?Nice detailed description missing this detail .
I,am thinking head gasket from excessive EGT. It’s the 80 % throttle that the give away for me on the current info ^^^ .

I reached 100 % load and soaring EGTs at 1400/1500 rpm not long ago , just about planning .Backed off immediately and sort a sterngear scrub .WOTs 2200 btw , turbos kick in around 1400 ish but the boost pressure is only starting to build .

You can not unfortunately rely on the jacket temp ( water temp gauge) , too bigger time delay .By the time it starts to climb with fouled sterngear because the cylinder temps + pressures are Immediately elevated by the overload caused by fouling there’s potential for localised damage .A gasket or something cracked letting gases mix .

I think the latest CR + powerful ECU,s + stuffed with electrotwackerey might prevent a forced overload theses days .

As far as the gas test in the coolant.....was it for diesels ?

Have you checked the oil filler cap for emulsion ? Sometimes coolant gets sucked in ?
Also any smoke.
I guess other stuff depends on the degree of severity of the HG breach ? A spectrum of signs + signals .

I can’t think of any other way the coolant boils up tbo .HG or cracked cylinder head .

 

[volvopaul]

Sorry to hear about this .
How clean is the stern gear ?Nice detailed description missing this detail .
I,am thinking head gasket from excessive EGT. It’s the 80 % throttle that the give away for me on the current info ^^^ .

I reached 100 % load and soaring EGTs at 1400/1500 rpm not long ago , just about planning .Backed off immediately and sort a sterngear scrub .WOTs 2200 btw , turbos kick in around 1400 ish but the boost pressure is only starting to build .

You can not unfortunately rely on the jacket temp ( water temp gauge) , too bigger time delay .By the time it starts to climb with fouled sterngear because the cylinder temps + pressures are Immediately elevated by the overload caused by fouling there’s potential for localised damage .A gasket or something cracked letting gases mix .

I think the latest CR + powerful ECU,s + stuffed with electrotwackerey might prevent a forced overload theses days .

As far as the gas test in the coolant.....was it for diesels ?

Have you checked the oil filler cap for emulsion ? Sometimes coolant gets sucked in ?
Also any smoke.
I guess other stuff depends on the degree of severity of the HG breach ? A spectrum of signs + signals .

I can’t think of any other way the coolant boils up tbo .HG or cracked cylinder head .

Porto why would you think it’s high EGT , Fairline a long with other UK builders very rarely got the exhaust size , route to exit or elbow height wrong , it’s the lesser builders or DIY people that got things wrong , Fairline used Manuflex or Halyard for their exhaust risers , elbows , silencers etc with a test port for the pyro and temp sensor .
This engine is a well proven model of which they rarely fail unless totally neglected.

Not really enough data from OP to diagnose as he’s not said what coolant temps he has before it dumps the coolant , this engine is edc so it won’t pull it’s full rpm if the coolant temp is high , it’s boost temp is high due to bad salt water flow through the intercooler .
This model is highly susceptible to cracked exhaust manifold which cause coolant loss and overheat .
Now it’s the chicken and the egg situation here , let say the coolant loss at first is through the manifold , there was a recall way back , coolant level drops , over heat causes high pressure in closed circuit , cap blows off , coolant expelled .

Or it could be that the raw water system is blocked , very likely if it’s never been cleaned , im guessing as it’s a 74 it’s circa 2000 to 2002 boat .

OP send more info .

 

[Portofino]

Porto why would you think it’s high EGT , Fairline a long with other UK builders very rarely got the exhaust size , route to exit or elbow height wrong , it’s the lesser builders or DIY people that got things wrong , Fairline used Manuflex or Halyard for their exhaust risers , elbows , silencers etc with a test port for the pyro and temp sensor .
This engine is a well proven model of which they rarely fail unless totally neglected.

Not really enough data from OP to diagnose as he’s not said what coolant temps he has before it dumps the coolant , this engine is edc so it won’t pull it’s full rpm if the coolant temp is high , it’s boost temp is high due to bad salt water flow through the intercooler .
This model is highly susceptible to cracked exhaust manifold which cause coolant loss and overheat .
Now it’s the chicken and the egg situation here , let say the coolant loss at first is through the manifold , there was a recall way back , coolant level drops , over heat causes high pressure in closed circuit , cap blows off , coolant expelled .

Or it could be that the raw water system is blocked , very likely if it’s never been cleaned , im guessing as it’s a 74 it’s circa 2000 to 2002 boat .

OP send more info .

Other than a manufacturing defect ( which you have eliminated) , theres no detail of the stern gear state , which I picked up on
“ current info given ^^ “ so the only conclusion for my “ A gasket or somethings cracked “ ..the source of the temp elevation is EGTs ....That’s is the logic thus far .
How else , or what else elevated temps to blow a gasket or crack something....like the E manifold you suggest from your intimate knowledge ?

 

[volvopaul]

Other than a manufacturing defect ( which you have eliminated) , theres no detail of the stern gear state , which I picked up on
“ current info given ^^ “ so the only conclusion for my “ A gasket or somethings cracked “ ..the source of the temp elevation is EGTs ....That’s is the logic thus far .
How else , or what else elevated temps to blow a gasket or crack something....like the E manifold you suggest from your intimate knowledge ?

No it is not why do you think every overheat is high exhaust gas temp ?
In 30 years I’ve only ever seen one engine fail through high EGT , this was a Caterpillar 3208 that had lost its impeller owner kept going hence it melted the exhaust pipe to the point it internally collapsed blocking the gas route .New impeller fitted but engineer never looked at exhaust , the blocked pipe caused high egt which took out the exhaust Valves.

High temp is caused by the lack of heat exchanger and intercooler to disperse the heat generated from both the coolant and the charge air from the turbo .

The exhaust manifold failure , cracking around no 6 port is a common issue as I’ve said already , I’ve done one this year on a Phantom .

The 74/75edc system pics up on foiled hull and stern gear through the edc recipe of info fed to it , fuel temp, boost temp, boost pressure, coolant temp , throttle position , all parameters give a suitable governor position that’s why this model of engine won’t pull full rpm when the hull is fouled and at the same time will give as good a clean burn as possible .

Overheat on this model of engine is mainly its cooling system clogged up with limescale , marine growth inside the coolers , plus oil mist deposits on the inside of the intercooler tube stack blocking the air tract .
Most engines of this age are now requiring a full strip , clean and rebuild of all coolers .

 

[Portofino]

Says “it’s annual service is due “ = suggest its being maintained.
says “it’s restarts “ ok .

If the E manifold was cracked and it cooled over night or what ever ? would coolant leak back , seep Into the manifold and possibly trickle back depending on the rock n roll , inclination etc ....back through open valves into the bore(s) .


No I,am not saying it is I,am say from the info provided thus far .I have qualified my response subject to that one detail - fouling being cleared up .Love him to say something along the lines ( it’s Mid August remember ) “ it’s just been antifoul ed/ lifted etc “
The Op post is silent on that and the previous temps Info you have requested .


I get your point if the coolers are clogged the manifold could relatively over heat and suffer thermal stress = fracture .

But without a EGT probe before the turbo .Ie between the where the 6 go into 1 , and the 1 enters the turbo ...he been blind .
The more throttle (80%) the more thermal stress .
He may have seen the decreased water flow through the E manifold as a rise in EGTs if the prob was where I describe .

All this happens long before his water temp gauge even twitches .

Obviously if he’s been running round at 89 degrees or what ever , 88 last year etc , then the clogged coolers moves to the top of the diagnostic tree .

But he’s not mentioned anything thus far about previous temps or his cooler strip down history .

We can only go on what he’s written thus far .....

A s I said a gaskets gone or somethings cracked ....just want to work out how ? Where’s the heat come from ?

 

[volvopaul]

Says “it’s annual service is due “ = suggest its being maintained.
says “it’s restarts “ ok .

If the E manifold was cracked and it cooled over night or what ever ? would coolant leak back , seep Into the manifold and possibly trickle back depending on the rock n roll , inclination etc ....back through open valves into the bore(s) .


No I,am not saying it is I,am say from the info provided thus far .I have qualified my response subject to that one detail - fouling being cleared up .Love him to say something along the lines ( it’s Mid August remember ) “ it’s just been antifoul ed/ lifted etc “
The Op post is silent on that and the previous temps Info you have requested .


I get your point if the coolers are clogged the manifold could relatively over heat and suffer thermal stress = fracture .

But without a EGT probe before the turbo .Ie between the where the 6 go into 1 , and the 1 enters the turbo ...he been blind .
The more throttle (80%) the more thermal stress .
He may have seen the decreased water flow through the E manifold as a rise in EGTs if the prob was where I describe .

All this happens long before his water temp gauge even twitches .

Obviously if he’s been running round at 89 degrees or what ever , 88 last year etc , then the clogged coolers moves to the top of the diagnostic tree .

But he’s not mentioned anything thus far about previous temps or his cooler strip down history .

We can only go on what he’s written thus far .....

A s I said a gaskets gone or somethings cracked ....just want to work out how ? Where’s the heat come from ?

Manifold is fresh water cooled so unless coolant level drops drastically it’s will be kept cool .
edc and gauge sender is front of manifold hottest point before it enters heat exchanger so gives highest coolant temp reading .
no space between manifold and turbo to fit probe in gas chamber as turbo bolts direct to manifold , when designers and builder test the probe goes in after turbo as gas is hotter just before it mixes with salt water .

I’d say his issues is with something as simple as a faulty cap or heat build up of coolant expanding pushing cap off its seat .
This is a simple proven engine of which give very little trouble .

 

[mlott]

Thanks for all you post. Sorry I missed a few important bits of info, it was late!

The boat was last lifted 2nd June. Props, rudders, & tabs had significant barnacle growth. Hull had only a light slim. All cleaned and relaunched 3rd June. I took her out for a spin and as I remember WOT 2600rpm 28.5kt (before the lift it was 14kt). Things took a turn for the worst on 7th Aug, so 9 weeks in the water. WOT was about 2100rpm 19kt, so I throttled back to 1900RPM. I made frequent gauge checks, oil good both temps bang on 80c and all was ok for about 5min, then with in 30sec of a gauge check, alarm sounding, gauge 130c. Immediately shut down both.

Other Q's

Service last year was Oil & Coolant change (50/50% green antifreeze/distilled water as the manual directs), all filters, tappets checked, new rocker gaskets. New Impellers, belts, engine anodes.

Heat exchangers have not been cleaned (ever I suspect). I had considered a full strip last service, but raw water flow was very good, and at that point no overheat issues at all, always bang on 80c under load, so it was decided to leave for the time being. (A decision I may now regret!)

Re. smoke. I had not noticed any at the time or after. I get a little from both when cold, as a very small amount of soot on the tender after a run, but I believe this is normal for these engines. Since the overheat nothing has changed.

CO2 test was done by my brother in law who is an experience lorry mechanic, so I'm sure his kit was for diesels. We tried several times but could not get even a hint of a positive.

The coolant bubbles even when the engine is stone cold, so I don't think it can be boiling anywhere.

I'm sure I've still missed something!

Thank again for your input guys.

Martin

 

[mlott]

Just reading back through the posts. I know I'd missed something.

No signs of any water in the oil. In fact no sign of coolant leaking out anywhere except the overflow.

I'd be interested on your thought of the fresh water pump being able to suck air in? If the heat exchangers are clogged there could be a below atmospheric pressure on the intake. Air being pulled in passed the input shaft seal maybe, or exchanger seals... It would explain the lack of CO2. It would also be fairly easy to fix too! Just because I've used distilled water, doesn't mean the previous owners have. There could be significant limescale in there.

Martin

 

[volvopaul]

Just reading back through the posts. I know I'd missed something.

No signs of any water in the oil. In fact no sign of coolant leaking out anywhere except the overflow.

I'd be interested on your thought of the fresh water pump being able to suck air in? If the heat exchangers are clogged there could be a below atmospheric pressure on the intake. Air being pulled in passed the input shaft seal maybe, or exchanger seals... It would explain the lack of CO2. It would also be fairly easy to fix too! Just because I've used distilled water, doesn't mean the previous owners have. There could be significant limescale in there.

Martin

The one I changed the manifold on showed no water in the oil until I did an oil sample which showed coolant in the oil so manifold was pulled , it was obvious when I pulled the manifold as coolant was sat in no 6 ex port .
where is your boat ?

 

[mlott]

Shamrock Quay, Southampton.

I already have the exhaust manifold off and didn't find any coolant. I've pressure tested it on the bench and so far found no leaks from the exhaust channel. The coolant channel does seem to have a oily film on it though. How obvious would a crack in the casting be? would it only show when heated by the exhaust gases?

Thanks again for your help.

Martin

 

[Portofino]

Can not see how air from the sea water pump if that’s what you mean by “fresh water “ getting into the closed cooling circuit .
Or air from the closed cooling side , but iam not familiar with this engines circulation system .
Thats one for Paul ?
Generally when boat pumps get air in they struggle to prime , develop suction so the flow rates drop off .If it’s the shaft seal the leak fluids drip out, or spurt out .
If it was an air in leak I,am speculating now , of the closed water pump seal ( if possible ? ) theses things come on slowly and you may have noticed gradual loss of coolant , + the odd drop in the bilge day by day as it’s started to seep out .....if it’s entirely possible that is .


Was the water temp 80 ish on first WOT after 3 rd June ?

Can,t see it clogging up coolers in 2 months 80 to83 to 85 to 89 , you see a gradual rise of jacket temps with time etc not this .

Can see fouled stern gear causing elevated EGTs ...+ concentration of thermal stress.....somewhere = crack .

Your give away In your first opening post for me was “80 % ...“..that’s your 80 % in man maths kinda way of the then Wot of 2100 , not the 80 % of 2600 .That suggest overload .Once overloaded they stay overloaded even down the rpm range .

The only anomaly is the BIL s gas tests coming through as -ve .



As I said I saw 100 % load and 680 EGTs at a lowly 1400 rpm with say 0.5 bar boost . 20-22 knots ....so I backed off immediately.
Boat left unused due to Corvid etc .
Because I have the luxury of seeing real time EGTs , the probe is just after the 6 converge before the turbo , and Load .
My engines are EDC just before CR so theres a certain level of elecrotwackery, if EGT s soar .I did get an alarm buzzer and screen msg “ engine overload “ and the overloaded one auto dropped to 1200 rpm ......think it was telling me something.

Normal turbo boost is 1.8-1.9 bar and EGTs between 550-600 degrees .
80 % load depending on fouling , time after its annual is circa 1800 rpm + or - a few rpm .Its not a % of the achieved then rpm .
The rpm at which 80 % is seen decreases with time until the next annual , as does the cruising speed .

 

[mlott]

When I say 80%, I just mean I was a little back from WOT (no maths involved!). In hindsight, I agree the engine was most likely still in overload. For the throttle position, I would of definitely got more RPM's with freshly cleaned stern gear certainly. With a clean bum, no tender, water or family on board, she has achieved 31.5kt GPS @2700RPM

I only have analog temp gauges so temps differences of a few degrees are not really detectable. Gauges on the whole, point straight up to 80c and a little lower at idle. RPM gauges do also take a little interpreting. I've not seen the temp over 80c before.


Martin

 

[Portofino]

Coolers sound in rude health .

Just need Volvo Paul to technically eliminate or confirm the closed coolant pump is not sucking in air form a leaky seal or what ever .My guess it can't ,

The gas test coming up - ve needs an explanation? Read somewhere if the apparatus has been oil film contaminated from oily coolant it knackers its ability to pick up pure exhaust gases so shows a false- ve .
Writing this blind of the apparatus used folks .

 

[volvopaul]

Coolant bubbles in header tank when stone cold means cylinder compression into water jacket , can only be a head gasket failure .
Any excess smoke from the two crank case filters ?

 

[mlott]

Not noticed any smoke.

Sounds like taking off the heat exchangers for a clean is a must, so heads off isn't that much further to go as the exhaust manifold is off already. The only problem is the head gaskets are listed as "out of production" with volvo. I guess they must be available somewhere as I'm told they are popular lorry engines.

Still think inspecting the water pump would be wise.

 

[Mr Googler]

Head gasket still made.....it’s just part of a kit with other seals

Volvo Penta Gasket kit (276816) - MarinePartsEurope.com

 

[MrB]

Head gasket still made.....it’s just part of a kit with other seals

Volvo Penta Gasket kit (276816) - MarinePartsEurope.com

^^^^^^^Should be renamed Google++++^^^^^^^?

 

[volvopaul]

Have you tested the thermostat

 

[superheat6k]

I had a similar problem on my TAMD60C due it turned out to a small perforation in the matrix of the plate heat exchanger. The sea water was at higher pressure within the exchanger so forced itself into the fresh water system, which in turn vented out of the pressure cap.

Although the symptom of bubbles was not apparent, so yes either a head gasket or manifold cross over / leak.

Pressure testing with compressed air in my workshop sink, the perforation was just visible from the edge of the matrix on one of the plates, and was a tiny hole, but there was no way the thing could be repaired.

Not sure what style of cooler the 74P has, but for the 60C is was very very expensive, especially from VP, although I did get a deal from Keyparts for buying two.

I did consider a conversion to a shell & tube Bowman, which now would likely be a requirement due to obsolescence, but the way the plate exchanger was mounted would not make that a simple task at all on the 60C engine.

Incidentally on those engines I did convert the gear oil coolers both to Bowman cupro nickel shell & tube coolers and at a fraction of the price of the awful brass affair VP designed. When finished the conversion looked like it was original fit.