VOLVO PENTA TAMD61A OVERHEATING - PLEASE HELP!

[patoim]

Originally Posted by Mitch C

Re the w/pump impellor - I'm talking about the fresh water/coolant/anti freeze/secondary pump NOT the seawater pump.
It's a hard plastic impellor in the water pump not the rubber one in the sea water pump
You will not see that this impellor is slipping by checking the raw water/sea water flow coming out of the exhaust

I've got the Volve service manuals for this engine if they would help? They are to big to attach to a post but I could PM them to you?

I have some manuals, but not all the services manuals, so if you can share them, I will appreciate, thanks 😊
The pump was always in the spotlight, we sent it for a complete renewal, so it should be working, but the attention is in the cylinder head now, as I will explain in a new post.

[patoim]

Well, I have some good and bad news, the bad is that the fifth cylinder have water, so there is a connection between the internal circuit and the cylinder, the good news is that we find something really important to address. Next step, I will send the cylinder head and probably the exhaust manifold (just because Its removed) for a hydraulic test, we still don’t know where the connection is, so will have all you posted.

I have one more issue to comment and ask for guidance. Yesterday, just before we removed the second cylinder head the mechanic discovered that the engine have a By-Pass Valve, which is used to divert the air to the aftercooler or close the circuit and pre heat the air for the engine start. In this last position, the air is pre heated and sent it to the engine, by passing the aftercooler, and it seems that there should be some kind of pneumatic pump to force the by pass to divert the hot air to the aftercooler so the air is inserted to the engine at lower temps. I do not have anything connected to ignite this contraction, so no air is going to the aftercooler, same in both engines. I understand that I could block this to force the air to circulate to the aftercooler, canceling the preheater function (which is not working btw). Photo attached.

I understand that this is not the main temp issue, but what do you think?

[rslifkin]

If you're getting coolant in a cylinder, you're probably pushing air into the cooling system as well. And that can be enough to cause overheating.

[patoim]

Originally Posted by rslifkin

If you're getting coolant in a cylinder, you're probably pushing air into the cooling system as well. And that can be enough to cause overheating.

Exactly, we will know for sure in a few weeks

[patoim]

Hello Everyone! I have great news, I found the main issue that was creating the heating problem. It was the coolant pump. I was sure that one of the previous mechanics had it check, but no, it was a painful and expensive mistake not to re check that simple pump. Attached is the photo of the pump, water was not circulating properly around the engine.

In the last few months, I did the hydraulic test on both cylinders head and exhaust manifold, I replace both cylinder gaskets, orings, everything until we found the problem in the pump.

I still have a few things to do generally in the boat, but the engine is perfect now!

Thanks to everyone that read and comment on this, hope that can be also useful for somebody in the future!

[skipperpete]

Thanks for the final report and congratulations on finally locating the cause of the overheating. Was a conclusion ever reached about the coolant in #5 cylinder?
DougR and MitchC definitely earned admiration for correctly identifying the circulating pump as the probable cause way back at the start of the thread despite the assurance that the circulating pump had already been repaired.

[patoim]

Originally Posted by skipperpete

Thanks for the final report and congratulations on finally locating the cause of the overheating. Was a conclusion ever reached about the coolant in #5 cylinder?
DougR and MitchC definitely earned admiration for correctly identifying the circulating pump as the probable cause way back at the start of the thread despite the assurance that the circulating pump had already been repaired.

Totally! This is my first boat so I take an important learning "never take your mechanic affirmation for granted"

I send a personal thank you message to DougR for his accuracy, i wll write also to MitchC.

The thing about #cylinder is that there was actually something to repair there, and it was repaired with the new gasket. That was not rhe main issue but was affecting the water temperature also. The whole nightmare left good maintanance practices and a lot of mechanical learning.

Thank to all!

[patoim]

Originally Posted by Mitch C

Make sure you check this - went through a similar path you have taken to fix o/heating in a 71B, and it turned out to be blocked where the water is injected into the exhaust.

One other thing to check - make sure, really make sure the impellor is firmly attached to the fresh water(coolant) pump shaft. I found one of ours would move forward on the shaft and then would not spin at higher engine speeds causing o/heat.

You were right about the pump! thanks Mitch!!

[Sevenrods]

Originally Posted by Sailormantx

I am working on a boat with Volvo TMD40A engines at the moment. After cleaning the cooling system and refilling it I had similar issues. The service manual isn't very clear with their descriptions but it is essential to get the air out of the cooling system at the turbo which is the highest point in the engine. On the TMD40A there's a small metal tube with a banjo fitting and a bleed screw with copper washers on both sides to seal it. My problem was that the hollow vent screw and it's hole in the side were packed full of gunk so nothing came out when it was loosened. After clearing that blockage I successfully vented the cooling system and the problem was solved. Note that the venting of the air is done when a clear bubble free steam of coolant comes out the same as venting the fuel system. This is done with the engine running so beware of hot coolant.

I have noticed over the last year a slight rise in temp on my 2 tamd61a...in particular starboard lAst year I did the aftercooler and heat exchanger csalt water coolers thoroughly. And have worked through the whole saltwater system to really get to the bottom of the issue...all ok at low revs...just when I increase.
Few things to share... don't forget oil coolers....mine were like a calcium wasp nest with a small hole for saltwater!!!
I cleaned out thoroughly...on reassembly struggling for space in my bilges and wondering why I wasn't born with 3 hands and a slim body!! I nearly reassembled the rubber hose on the gearbox oil cooler without looking at the metal flange opening that attaches with 4 bolts that was almost totalally blocked.!!!!
The other surprise I got was my exhaust rubbers are huge, someone in Spain replaced standard vp exhaust elbows wit h a monster stainless steel bespoke version of abou7.5 inches diameter and a metre long 7.5 inch rubber water exhaust. Thie stainless was pristine. The 7.5 inch rubber exhaust could not block!!!!!
But it was!!! From the outside it always looked fine
But the inner layer of the pipe had imploded and was reducing the flow, Don't forget anodes on oil coolers and heatexchanets and after coolers.
When cleaning off the mussels on my saltwater intakes
After 18months I had more than what tesco sell on each engine intake than they supply in a bag.
I also cleaned out the filters.
I nearly missed the critters growing between the intakes and the valves...the tiny mussel spats had come thru grill and grown in the sea side of the valves on the sea cocks.
Hopefully in process of putting everything back together now.
But thought I would share so others are aware!!!

[Sabre 30]

Similar issue, hx leaking inside...loosing coolant level. Can I change thermostat and run as raw water cooled engine? Crazy I know but even the piping to change to raw water cooled is expensive. No leaks external from hx.

[Celik2828]

[QUOTE=patoim;3755816]Merhaba Sevgili Topluluk, deneyiminize ihtiyacım var, VOLVO TAMD 61A'mdan (1989) biriyle sıkışıp kaldım, Klasik bir aşırı ısınma vakası gibi görünüyor ama neredeyse tüm temel bilgileri kontrol ettim: Durum: - 1000rpm'den daha az koştuğumda sorun yok. - 1400/1500 rpm'ye götürür götürmez sıcaklık alarmı çalar ve gösterge 100°C'yi işaretliyor. Bir dakikadan az sürer. - Bağlantı noktası motorunu 1500'e ve santak tarosunu 1200'e ayarlarsam, sıcaklık kontrol altında. Biraz daha ileri gitsem de kontrol altında, her zaman 300/400 rpm farkla. İşaretler: - Egzozdan her zaman su çıkıyor. - Biraz dumanım var, biraz karanlık ama normal dışı bir şey yok, 30 yaşındaki biri için motor. - Garip sesler veya herhangi bir şey yok - Yağ ölçüm çubuğunda su kanıtı yok - Bir gösterge veya gönderen sorununu atmak için sıcaklığı zaten test etti. Yapılan şeyler: - Deniz suyu çarkı değiştirildi. - Onarılmış tatlı su pompası - Isı Eşanjörünü tamamen temizleyin - Yeni bir Termostat koyun, onsuz çalıştığımı keşfettim. - Kemer değiştirildi. Bir sonraki adım silindir kafalarını açmaktır.... Hangisinden kaçınmak istiyorum, herhangi bir fikir? Herkese şimdiden teşekkürler![ /TEKLIF]

Hello my friend. I have tamd71a. I am experiencing exactly the same heating problem as you. Can you help me? The sea water pump was checked, the thermostat was checked, the temperature sensor was checked, the condensates and aftercooler were cleaned, the fresh water pump was also inspected and even the repair kit was changed due to leakage last year. There is no decrease or pressure in the spare water tank. The engine was completely revised last year. .this problem has just started

[jamhass]

An item I didn't see mentioned but worth checking in general when overheating issues is the raw water pump cover itself. The pump body (including the cam) may be fine, but grooves in the pump cover can result in overheating at higher revs. A flat surface (nice piece of glass) and sandpaper (to 400 grit or so) works fine.

[Celik2828]

Originally Posted by patoim

Hello Everyone! I have great news, I found the main issue that was creating the heating problem. It was the coolant pump. I was sure that one of the previous mechanics had it check, but no, it was a painful and expensive mistake not to re check that simple pump. Attached is the photo of the pump, water was not circulating properly around the engine.

In the last few months, I did the hydraulic test on both cylinders head and exhaust manifold, I replace both cylinder gaskets, orings, everything until we found the problem in the pump.

I still have a few things to do generally in the boat, but the engine is perfect now!

Thanks to everyone that read and comment on this, hope that can be also useful for somebody in the future!

What is the problem with your pump? I couldn't see the image

[Celik2828]

Today I disassembled the fresh water pump again and this time I dismantled the inside. There is no problem. The shaft is solid and there is no scraping on the impeller. I broke it off and removed it. I have a spare repair kit on hand, I will install it. The problem continues.

[skipperpete]

Originally Posted by Celik2828

Today I disassembled the fresh water pump again and this time I dismantled the inside. There is no problem. The shaft is solid and there is no scraping on the impeller. I broke it off and removed it. I have a spare repair kit on hand, I will install it. The problem continues.

You need to go back to the start of this thread and read the replies and suggestions by DougR, MichC and a few others who actually know what they’re talking about.
The specific causes of engine overheating are often difficult to isolate but all can be attributed to a single factor, “the failure of the engine to reject the heat produced”. It could be because of something as simple as coolant gelling after mixing an incompatible coolant (a suggestion from Volvo) or something as complicated as a cavitation pinhole through a wet liner wall. The approach is not to randomly keep assuming some specific part of the system is the culprit and dismantling it, far better to ascertain what’s working exactly as it should be and what’s NOT. Find out what the output of the raw water pump is at various rpm and physically measure it with a bucket and stopwatch,….. go over the entire cooling system with an IR laser temp probe and record the various in and out temps on both ends of all heat exchangers and intercoolers ( this can take an hour or more if you do a thorough job)…. If you have a twin installation, compare the healthy engine circuit temps with the overheating one.
You need to regard the entire installation including the propeller as potential causes of either incompetent heat rejection or excessive heat output.