617 cooling problems
617 cooling problems
I am currently putting a 617.952 into a boat . I have the cooling system hooked up exactly as it would have been in a mb car with a marine heat exchanger in place of the radiator. Once the engine gets hot only steam comes through the small tube to the over flow. I have tried getting all the air out of the system and the min the engine warms up all I get is steam. When I open the radiator cap when engine is hot coolant comes spewing out. Once it stops spewing coolant it occasionally will pump a small amount of coolant fallowed by yet more steam... Help!
There's air in the cooling system.
Make sure you fill it at the highest point possible.
Do you have the thermostat fit in the right position.
Sometimes the padles of the water pump are damaged causing a faulty function.
Have the engine run without the radiator cap!
What did you do to the heater side connection?
If you have a hard time starting the engine there might be cracks in the cilinderhead as well.
(06-22-2010, 02:13 AM)plurkje There's air in the cooling system.
Make sure you fill it at the highest point possible.
Do you have the thermostat fit in the right position.
Sometimes the padles of the water pump are damaged causing a faulty function.
Have the engine run without the radiator cap!
What did you do to the heater side connection?
If you have a hard time starting the engine there might be cracks in the cilinderhead as well.
(06-22-2010, 02:13 AM)plurkje There's air in the cooling system.
Make sure you fill it at the highest point possible.
Do you have the thermostat fit in the right position.
Sometimes the padles of the water pump are damaged causing a faulty function.
Have the engine run without the radiator cap!
What did you do to the heater side connection?
If you have a hard time starting the engine there might be cracks in the cilinderhead as well.
where is the marine heat exchanger in relation to the motor? Is it lower, higher? Is it possible that its a little lower than a stock radiator would have been placed and a large air pocket is stuck in the block, and causing it to spill when the cap is opened? Normally, you should be able to start the car with the cap off and let it run without it overflowing, but your setup is so custom that it would be hard to say.
Do you have any pics?
Could you provide some overview pictures?
Something is horribly wrong.
These engines should be able to run with the cap off untill the thermostat is fully open without any steam build up.
Some of our engines are with a bypass and some don't have it, so check if yours has a bypass from the pump housing to the cilinderhead, it's a small C shaped tube (on the outside). If you don't have it you could fit it, the holes are already there.
The best way is to do a vacuum fill! It pulls a near 100% vacuum on the cooling system then it uses the vacuum to fill the coolant in and there will be no air pockets left! best of luck
(06-22-2010, 04:59 PM)willbhere4u The best way is to do a vacuum fill! It pulls a near 100% vacuum on the cooling system then it uses the vacuum to fill the coolant in and there will be no air pockets left! best of luck
(06-22-2010, 04:59 PM)willbhere4u The best way is to do a vacuum fill! It pulls a near 100% vacuum on the cooling system then it uses the vacuum to fill the coolant in and there will be no air pockets left! best of luck
(06-22-2010, 08:54 PM)aaa Still sounds like air. Punch a hole in the t-stat then let it sit for bit after you fill it. Better yet just try it again if you haven't already, sometimes the air clears up from just sitting.
(06-22-2010, 08:54 PM)aaa Still sounds like air. Punch a hole in the t-stat then let it sit for bit after you fill it. Better yet just try it again if you haven't already, sometimes the air clears up from just sitting.
Iis the fill point for the cooling system the highest point in the system? IE is it higher than the cylinder head?
(06-22-2010, 11:08 PM)willbhere4u Iis the fill point for the cooling system the highest point in the system? IE is it higher than the cylinder head?
(06-22-2010, 11:08 PM)willbhere4u Iis the fill point for the cooling system the highest point in the system? IE is it higher than the cylinder head?
[quote=. my next question is how hot is too hot for these engines? i hope that i have not damaged it.
[/quote]
They used to say; it's safe untill you reach the red bar in the gauge! I don't know what gauge you use. And how far it's been.
On the other hand, I use to have a faulty gauge (showing higher temps and faster rise) killed the cilinderhead.
These heads can withstand great temperatures, so you're probably safe. If not you'll now soon due to extreme build up of exhaust gas.
I think the red bar on the Mercedes is about 250*F
Oops! did that once....
I still don't think it would hurt it very much!
Not as much as the engines with aluminum heads, but still not something to be considered "okay" on a regular basis.
240 is as hot as the engine got and it was for less than 30 seconds... the air started to burp out and coolant started to flow better .... i did have one hot spot that got to 270 where there was an air pocket at the heater core attachment on the top of the head.
do you have a pic of the water pump? Who was the manufacturer?
Sounds like you will have it all ironed out now that something is actually pumping coolant. No wonder you had excessive steam buildup.
(06-24-2010, 07:44 AM)dropnosky do you have a pic of the water pump? Who was the manufacturer?
Sounds like you will have it all ironed out now that something is actually pumping coolant. No wonder you had excessive steam buildup.
(06-24-2010, 07:44 AM)dropnosky do you have a pic of the water pump? Who was the manufacturer?
Sounds like you will have it all ironed out now that something is actually pumping coolant. No wonder you had excessive steam buildup.
Was it a press fit on there? I've never had a problem with any of the original pumps even 20-30 years later?
If it wasn't press fit, maybe someone spaced a welding process and forgot to secure the impeller to the shaft.
Had a jeep once where some A-hole at the factory only welded 1/4 of the clutch pedal arm to the pivot point part. Result was I was driving along, went to downshift and the pedal arm actually broke off and fell onto the floor.
Could not believe it after I got it all apart.
Sounds like your TSTAT is not working properly. Can you rig up a water pump to duplicate the flow of the HVAC in the benz? This is how the system is burped.
The heater core should make no difference to cooling or venting, thats why the bypass passage is drilled in the thermostat housing to the upper radiator hose. Its not the highest point in the head and the flow is usually shut off completely during warm weather anyways.
I've had no water problems at all in my 300D without the HVAC system. It goes straight to 82*c and stays there.
Worst case, put a bleed cock there.
Yes it was a press fit impeller.... I am thinking about putting a bleed cock to plug up the heater core fittings..... I always dread looking for the correct sizes of fittings for this motor cause people just stare at me and say "metric ? what? no we don't have anything metric thread" does anyone know the size of the fitting in the head and where the temp sensor screws in?
I just pulled the plug and drilled/tapped it for 1/2NPT. The water pump I believe was tapped for 1/4NPT.
(07-02-2010, 12:21 AM)Actros617 You might want to place 3 or 4 raw water heat exchangers and install a raw water pump. That way you can keep the engine cooler.
(07-02-2010, 12:21 AM)Actros617 You might want to place 3 or 4 raw water heat exchangers and install a raw water pump. That way you can keep the engine cooler.
(07-02-2010, 12:24 AM)polarisrmk(07-02-2010, 12:21 AM)Actros617 You might want to place 3 or 4 raw water heat exchangers and install a raw water pump. That way you can keep the engine cooler.
I think if this one heat exchanger can keep a 400 hp 7.4 liter v8 engine cool i can surely keep a 3.0liter 5 cyl cool ..... it already has a raw water pump. these exchangers are very expensive (around $400-$500 used).
(07-02-2010, 12:24 AM)polarisrmk(07-02-2010, 12:21 AM)Actros617 You might want to place 3 or 4 raw water heat exchangers and install a raw water pump. That way you can keep the engine cooler.
I think if this one heat exchanger can keep a 400 hp 7.4 liter v8 engine cool i can surely keep a 3.0liter 5 cyl cool ..... it already has a raw water pump. these exchangers are very expensive (around $400-$500 used).
The heat exchanger that he has is MORE than adequate for the application. Just make sure the marine gear has it's own exchanger, too. To simulate water flow, a 3/4" garden hose hooked to the raw water pump is adequate for basic running tests. This comes from many years experience working on boats. On Google, search for "OM617 Uniflite (uniflight maybe) & you will find a person that stuffed 2 of them in a 26 - 28 footer. He may have some more practical info. MOST IMPORTANT: the largest raw water sea strainer that you can afford/fit.If you have alot of sargassum in your area, it will be a life saver.
Run a test: Remove the thermostat from the thermostat housing. Bleed the system. Then run the engine to see if the overheating issue changes. If it gets cooler then the thermostat is probably at fault or you had a large air pocket in your thermostat housing, which was keeping the thermostat from being submerged in coolant. Additionally is the thermostat a Behr? If it is an aftermarket it is probably not functioning properly. Of the many MB diesels I have owned over the years each time I tried a non OEM brand it failed to work properly.
And finally thinking way out of the box (just for fun): For additional cooling you could utilize the heater in and out pipe and route them to a separate smaller heat exchanger independent of the main system.
Mark
(07-13-2010, 07:10 PM)inkblotz Run a test: Remove the thermostat from the thermostat housing
(07-13-2010, 07:10 PM)inkblotz Run a test: Remove the thermostat from the thermostat housing
You are correct I misspoke. First mistake this year.
I am not that familiar with Boat heat exchangers other than on some the water that they are floating in is used in some way for cooling. If this is the case would that not put the exchanger well below the level of the motor?
I still believe that there is a pocket of air in the system not allowing the thermostat to open properly or that the thermostat is a faulty aftermarket product.
Perhaps I will leave this problem to those with more substantial sea legs.
Mark
How is the hot water form engine entering the heatexchanger?
If the hot side enter at same or lower then the cold return to engine, the engine waterpump might not manage to keep the circulation up due to the natural effect from the cooling that force cold water down. Think of how it is in the car, hot water on top of radiator, the cooled water return to engine at the bottom.