TAMD41A Reservoir/radiator cap

[Timmy]

Hello,

Have coolant pushing past my reservoir/radiator cap.

Engine does not over heat and temps are normal.

Head gasket was replaced 6 years ago, never overheated motor........

Made two runs this year and each time had coolant in bilge from cap area.

Likely hood of weak/defective cap(1989)?


Timmy


ps Also, while looking for a part number for my specific cap and my particular engine, I could not find a parts diagram that was exact to my engine. Anyone know of an online parts diagram (looked at google and those top 3-5 searches were unsuccessful)

 

[kehoff]

they make a radiator pressure tester that also did radiator caps , it may be cheaper to just put a cap on , what motor and how hot is it getting ?

 

[Timmy]

they make a radiator pressure tester that also did radiator caps , it may be cheaper to just put a cap on , what motor and how hot is it getting ?

motor runs at 60c

volvo penta tamd41A

 

[Timmy]

motor runs at 60c

volvo penta tamd41A

correction on temp 160-170 F

 

[bigjay]

Hi Tim,

I had a TAMD41a and had trouble finding parts for it.
You can try european volvo websites to identify part numbers like marine parts europe
I believe the part number for the cap is 845879 for a 41a circa 1989
If you are on the east coast give Brian McDonnell at Mcdonnell marine in connecticut a call. He can confirm and likely has the part or can get it. A pleasure to work with.
Hope this helps

 

[kehoff]

as the engine heats up it will push coolant into the "overflow" tank ,and when it cools it pulls the coolant back in , keeping the coolant level at the same point, but it should not fill/overflow the tank , make sure the overflow tank and hose are good , no holes etc , I would stick a cap on just for good measure , the fact that the temp is ok is a good sign . I also think there may be more going on , has the seawater pump been serviced , the heat exchanger serviced ?

 

[winterking]

dont mean to derail the subject but it's not totally off topic, not the sea water pump but does the coolant circulation pump ever spring a leak on these 41 motors? been chasing a coolent leak myself.

 

[captjohn]

Hi Tim,

I had a TAMD41a and had trouble finding parts for it.
You can try european volvo websites to identify part numbers like marine parts europe
I believe the part number for the cap is 845879 for a 41a circa 1989
If you are on the east coast give Brian McDonnell at Mcdonnell marine in connecticut a call. He can confirm and likely has the part or can get it. A pleasure to work with.
Hope this helps

I've got two of them and have NEVER had problems with getting parts.

 

[steveinak]

dont mean to derail the subject but it's not totally off topic, not the sea water pump but does the coolant circulation pump ever spring a leak on these 41 motors? been chasing a coolent leak myself.

yes and look on the front of the motor around the thermostat housing there is a short hose there that would dribble out coolant every winter then after i got fishing and it got warmer out would stop leaking.

 

[Genius]

dont mean to derail the subject but it's not totally off topic, not the sea water pump but does the coolant circulation pump ever spring a leak on these 41 motors? been chasing a coolent leak myself.

common leaks are the plastic tube from the exhaust manifold to the thermostat housing. The coolant pump will leak when worn out, but not an issue with these engines. Another location is the exhaust manifold, at the rear there is an o ring that fails. Exhaust manifolds are know to crack after overheat events. Sometimes they can only become apparent when running/hot/loaded. Of course, the turbo install if not done correctly can cause coolant leaking into the exhaust manifold.

 

[Genius]

yes and look on the front of the motor around the thermostat housing there is a short hose there that would dribble out coolant every winter then after i got fishing and it got warmer out would stop leaking.

yup, a bitch to change out that tube and o rings.

Mine did the same thing, noticed it in winter. In the summer time, never leaked.

 

[steveinak]

yup, a bitch to change out that tube and o rings.

Mine did the same thing, noticed it in winter. In the summer time, never leaked.

changed it out once and still did the same thing so every winter id have bilge of green ! once i found it i made up a catch funnel and a jug to reuse it in the spring. Volvo shit engineering strikes again.

 

[Genius]

changed it out once and still did the same thing so every winter id have bilge of green ! once i found it i made up a catch funnel and a jug to reuse it in the spring. Volvo shit engineering strikes again.

Did you change the plastic tube and two o rings. All new? I was advised to do that. If I hadn’t, I would’ve just done the o rings.

 

[Timmy]

update.........

it turns out the radiator cap was not all the way tightened....

the hose clamp for the plastic overfill reservoir had shifted and was jamming the radiator cap when you go to install cap.

I would feel the cap hit the hose clamp and stop,

after installing a new cap and applying some force to ensure the cap was on all the way, it became apparent that I was not installing the radiator cap correctly.........

I had done other work over winter and needed to move coolant overfill tank out of way and missed that hose clamp has shifted against the radiator cap.

Made my 3rd run of season and no coolant in bilge

Just when you think you may know what you are doing, reality slams you in the forehead like a sledge hammer


Thank you all that replied, I hope there are not too many more of these occurrences


Timmy

 

[steveinak]

Did you change the plastic tube and two o rings. All new? I was advised to do that. If I hadn’t, I would’ve just done the o rings.

yeah all new parts and pita to change especially when its 10 degrees out so i'd light the dickinson diesel stove and let it warm up the cabin for a couple of hours before i did any work.

 

[magic dyer 29]

Hello,

Have coolant pushing past my reservoir/radiator cap.

Engine does not over heat and temps are normal.

Head gasket was replaced 6 years ago, never overheated motor........

Made two runs this year and each time had coolant in bilge from cap area.

Likely hood of weak/defective cap(1989)?


Timmy


ps Also, while looking for a part number for my specific cap and my particular engine, I could not find a parts diagram that was exact to my engine. Anyone know of an online parts diagram (looked at google and those top 3-5 searches were unsuccessful)

I replaced my pressure cap and same situation still occurs where coolant flows out after a days run. I added an overflow tank and it catches the overflow but doesn’t siphon back after cool down. I then use turkey baster to pull out of overflow tank and put back into heat exchanger expansion tank. Volvo Penta dealer said later engines had overflow tanks but they were piped differently to engine.
See photos attached of my TAMD 41A
Pressure cap with part number shown. It’s 50kpa which is about a 7lb relief pressure.
Paul

 

[Genius]

I replaced my pressure cap and same situation still occurs where coolant flows out after a days run. I added an overflow tank and it catches the overflow but doesn’t siphon back after cool down. I then use turkey baster to pull out of overflow tank and put back into heat exchanger expansion tank. Volvo Penta dealer said later engines had overflow tanks but they were piped differently to engine.
See photos attached of my TAMD 41A
Pressure cap with part number shown. It’s 50kpa which is about a 7lb relief pressure.
Paul

View attachment 159964

View attachment 159965

You must have the wrong cap or overflow tank

 

[magic dyer 29]

You must have the wrong cap or overflow tank

Genius,
As Volvo-Penta didn’t offer an overflow tank or “pressure-vacuum“ pressure cap for heat exchanger on a circa 1987 TAMD41A diesel,I am not sure what you are saying wrong cap or overflow tank. Cap is factory correct V-P part.
If you have the same engine on your boat, I , and the forum members would appreciate your feedback with part numbers for the “ correct” cap and overflow tank, for this specific engine.
As we all know getting parts for 30+ year old diesels can be a challenge.
Thank you,
Paul

 

[Genius]

Genius,
As Volvo-Penta didn’t offer an overflow tank or “pressure-vacuum“ pressure cap for heat exchanger on a circa 1987 TAMD41A diesel,I am not sure what you are saying wrong cap or overflow tank. Cap is factory correct V-P part.
If you have the same engine on your boat, I , and the forum members would appreciate your feedback with part numbers for the “ correct” cap and overflow tank, for this specific engine.
As we all know getting parts for 30+ year old diesels can be a challenge.
Thank you,
Paul

…then, you’re putting too much coolant in the expansion tank. Don’t fill it up.

 

[magic dyer 29]

…then, you’re putting too much coolant in the expansion tank. Don’t fill it up.

Much appreciated will try that this season.
Thank you,
Paul