I have a cummins 4cylinder and I’m having trouble keeping it cool. It all started when I had some shells rip my impellor to bits, I replaced that and still over heating so I replaced the thermostat just for the hell of it and still overheating, I had a pretty good flow over the side so I didn’t check the. Exchanger but I thought. I would call the Cummins guy to have a look and he can’t work it out either… So I’m just wondering if anyone has any thoughts on the matter… Anything would be Great thanks
Cheers
Berkeley
Could be the shells are blocking just enough tubes/plates in the heat exchanger to cause the engine to overheat, but not really enough to affect the flowrate? Just a guess though…
If the impeller got ripped to bits where do you suppose all those bits went to live?
On my Volvo penta diesel with antifreeze cooling and heat exchanger I had over heating problems, put a new thermostat, new impeller( just gushed water over the side of the boat), replaced some seals that where leaking a little bit, vacuum bled the cooling system to make sure no air pockets in the block/head where causing my problem. Still overheated.
The problem was even though the pulley on the coolant circulating pump was spinning, the impeller on the inside was separated and was not moving coolant through the heat exchanger. new 450$ volvo water pump, she ran like a champ and I had no more problems.
Hope you get it figured out.
They swapped the heat exchanger (i have a twin) and same thing. Sorry was just told that by the owner I work for today,still might give the oil cooler a good clean and a guest on board tonight who is a diesel mech was telling me to perhaps flush the coolant side a few times and maybe try a better fluid. It’s a turning into a good ol detective story for sure, keep ya posted… Thanks for the advice guys…fair winds
Thanks GLMASailor sounds very similar, seeing how the shells ripped up the impeller to start with the pump might be a good place to get into… Thanks, will let you know what happens…
Just OOC, what type coolant was put into after the first coolant exchange. Some engines require a specific coolant. even a little bit off will negatively effect the ability of the coolant to exchange heat in the plate coolers. (or the after coolers)
Yer coolant research is on the “to do list” for this week but I have a little of the new coolant in the port side but after we replaced the thermostat we pretty much filled up the starboard with the new stuff so I gotta flush it and try recommended…
[QUOTE=cappy208;49351] Some engines require a specific coolant. even a little bit off will negatively effect the ability of the coolant to exchange heat in the plate coolers. (or the after coolers)[/QUOTE]
Some manufacturers specify a coolant because it has been proven to reduce corrosion in their engines and it may contain additives which they have found helps reduce liner erosion. As far as the ability of a coolant to transfer heat, the difference between pure water and pure “coolant” or antifreeze is difficult to measure with the instrumentation normally installed.
Choosing the wrong brand of coolant for a certain engine might result in long term problems related to corrosion or erosion but claiming it will cause immediate overheating due to its heat transfer characteristics is nonsense.
I wish for that to be true!! Some coolants have different wetting ability. I am not an engineer, and can’t pretend to be one, but having run brand new MTU’s with the wrong coolant in them for three months, it became obvious that different coolant DOES have different specs that impair the ability to ‘let’ heat exchanger plates slough off the heat to the other side. BTDT.
I only mentioned this, since it would be apparent that if water pumps, heat exchangers were removed, and coolant loss would have happened. And whatever was replaced could possibly affect the cooling ability of modern, hi tech coolant systems on these ‘little’ high speed diesels. Stranger things have been known to happen, and this guy is reaching for possible solutions, or issues to look at.
Like I wrote: “…claiming it will cause immediate overheating due to its heat transfer characteristics is nonsense.”
Given the history of this problem, overheating may be related to trapped air or a cracked liner or warped head due to severe overheating during the initial incident. If it developed over a longer term and the type of coolant used in the refill was incompatible with the previous coolant, it is possible that the additive package “dropped” a load of silicates or precipitated a sludge that can cause heat transfer problems over a period of time … like your 3 months but not in 3 minutes or 3 hours.
A coolant analysis along with more detective work is in order. Given the extent of the work that (we are learning with each post) was performed we are probably missing a lot of troubleshooting information.
[QUOTE=Steamer;49425]Like I wrote: “…claiming it will cause immediate overheating due to its heat transfer characteristics is nonsense.”
Given the history of this problem, overheating may be related to trapped air or a cracked liner or warped head due to severe overheating during the initial incident. If it developed over a longer term and the type of coolant used in the refill was incompatible with the previous coolant, it is possible that the additive package “dropped” a load of silicates or precipitated a sludge that can cause heat transfer problems over a period of time … like your 3 months but not in 3 minutes or 3 hours.
A coolant analysis along with more detective work is in order. Given the extent of the work that (we are learning with each post) was performed we are probably missing a lot of troubleshooting information.[/QUOTE]
That’s all correct. Too little info. It would help to see the Cummings tech report.
Is there combustion gas in the cooling system? Is the engine shutting down on high JWT? If so, do the mechanical gages indicate high JWT? Is the JWT sensor calibrated? Is JW circulation visible? I have seen spun impellers. Many more questions if they’re electronic controled engines and don’t have an interface.
I just dropped it at the mechanic, what a drama that was, not only was it tight but had a nice wind blowing me off and I had to use the bad side cooking it a little more but what can ya do…
The guy said it might have compression gas or exhaust in the system so they gonna test for that. Hopefully it’s nothing serious or more to the point something I’ve done seriously wrong, I’m sure the problem is beyond my MED2 skills at this point so it’s outta my hands… Stay tuned
Ok, well turns you guys are actually chatting to an idiot… didn’t put the impeller in right… I’m in the bad books big time, sorry guys… Might be time to start thinking about a career as a dish washer…!!!