Cm2350 leak down failed

[Tony]

I understand that. I was impressed with the quality of them, but Im obviously not a professional. I would be willing to send you one to get your opinion. I don't want to recommend something that could get someone hurt or killed.

[Rawze]

just call up a few different OEM places .. tell them your leased onto a large mega-fleet of your choice (for the discount code), but that you pay for your own parts as an owner-op ... and say the place down the street sells them for (about $ 150-200 less) and make them compete for the lowest price.

btw, cummins franchises are typically the most expensive, and pete or International stealers$its are far cheaper for exactly the same engine part#.

Volvo franchises are typically higher than other stealers$its too. At least they are around here any ways.

Just because someone's truck might be a KW .. does not mean a person cannot buy the engine parts at a freightliner dealers$it. OEM certified Engine parts are same at all of them.

[kjjohnson1980]

Since the injector test passed and there are no codes, it might be a good idea to start by replacing the pressure relief valve. It's a relatively simpler and cheaper fix, so it's worth a shot. If that doesn't solve the issue, you can consider getting fuel rail caps to test each injector individually as a next step.

[Tony]

Update: I swapped injector #5 out and reset it with insite. Preformed a leakdown test and only dropped 500psi in a min.

I just wanted to say thank you everyone for your suggestions and help. I definitely learned a few things along the way.

[Canadian Trucker]

I also have a cm2350 Cummins ISX15 that fails that injector leak down test horribly, I timed it for a minute and it dropped from 29,200~ to about 4,000 psi. I guess my main question is what are the consequences of running it like this? I don’t have any check engine light or rough idle or bad fuel mileage or any of the other symptoms i have heard other people having with way less of a drop than mine has. My demandate tune is Rawze approved, and also I replaced that check valve at the end of the rail already, and fuel pump was changed with OEM rebuilt about 200,000km ago. I change oil and sample at 500 engine hours and my fuel dilution is always less than 0.1%. I have ordered 3 of the cummins fuel rail plugs and do plan to test the injectors eventually, just not getting the whole picture of the severity of the excessive fuel pressure drop I guess. If someone can explain it to me would be great! Thanks.

[Rawze]

(12-15-2023 )Canadian Trucker Wrote:  I also have a cm2350 Cummins ISX15 that fails that injector leak down test horribly, I timed it for a minute and it dropped from 29,200~ to about 4,000 psi. I guess my main question is what are the consequences of running it like this? I don’t have any check engine light or rough idle or bad fuel mileage or any of the other symptoms i have heard other people having with way less of a drop than mine has. My demandate tune is Rawze approved, and also I replaced that check valve at the end of the rail already, and fuel pump was changed with OEM rebuilt about 200,000km ago. I change oil and sample at 500 engine hours and my fuel dilution is always less than 0.1%. I have ordered 3 of the cummins fuel rail plugs and do plan to test the injectors eventually, just not getting the whole picture of the severity of the excessive fuel pressure drop I guess. If someone can explain it to me would be great! Thanks.

The consequences if it is an injector leaking into a cylinder, is fuel impingement (dried fuel crud) buildup, and it will take out the cylinder. In fact, it don't take much at all to wipe out a cylinder or eat the valve train up.

I just saw one a few weeks ago that this happened to in fact ... it was over at Mr. Hags shop being inframed,.. and the piston in that cylinder was covered in crud.. it ate the valve seats up and eventually blew the head gasket. Engine had low miles on it. I was told that what's even worse is that the truck owner refused to have the issue fixed, ran it several months after finding about it, knowing it was an issue.

I should have taken pictures of the cylinder.. it looked pretty bad and it was obvious that a leaky injector took it out.

He learned the hard way that it voided his warranty and now the engine needed an inframe to fix a problem he could have completely avoided.

Also, it over-works the crap out of the fuel pump, causes the fuel to run hotter usually, and this wears out the pump and accelerates wear in the fuel system, pushes other injectors towards failures.

I.E.> It is nothing at all to take for granted just because someone 'feels' like its running ok.

You also loose fuel mileage because the pump is working its arsse off all the time too.

----

Trying to save a dollar in trucking on proper repairs and maintenance of especially that engine .. ALWAYS ALWAYS costs thousands (sometimes tens of thousands) of unnecessary $$$$$ down the road, and a whole lot of regrets.

[Canadian Trucker]

(12-15-2023 )Rawze Wrote:  

(12-15-2023 )Canadian Trucker Wrote:  I also have a cm2350 Cummins ISX15 that fails that injector leak down test horribly, I timed it for a minute and it dropped from 29,200~ to about 4,000 psi. I guess my main question is what are the consequences of running it like this? I don’t have any check engine light or rough idle or bad fuel mileage or any of the other symptoms i have heard other people having with way less of a drop than mine has. My demandate tune is Rawze approved, and also I replaced that check valve at the end of the rail already, and fuel pump was changed with OEM rebuilt about 200,000km ago. I change oil and sample at 500 engine hours and my fuel dilution is always less than 0.1%. I have ordered 3 of the cummins fuel rail plugs and do plan to test the injectors eventually, just not getting the whole picture of the severity of the excessive fuel pressure drop I guess. If someone can explain it to me would be great! Thanks.

The consequences if it is an injector leaking into a cylinder, is fuel impingement (dried fuel crud) buildup, and it will take out the cylinder. In fact, it don't take much at all to wipe out a cylinder or eat the valve train up.

I just saw one a few weeks ago that this happened to in fact ... it was over at Mr. Hags shop being inframed,.. and the piston in that cylinder was covered in crud.. it ate the valve seats up and eventually blew the head gasket. Engine had low miles on it. I was told that what's even worse is that the truck owner refused to have the issue fixed, ran it several months after finding about it, knowing it was an issue.

I should have taken pictures of the cylinder.. it looked pretty bad and it was obvious that a leaky injector took it out.

He learned the hard way that it voided his warranty and now the engine needed an inframe to fix a problem he could have completely avoided.

Also, it over-works the crap out of the fuel pump, causes the fuel to run hotter usually, and this wears out the pump and accelerates wear in the fuel system, pushes other injectors towards failures.

I.E.> It is nothing at all to take for granted just because someone 'feels' like its running ok.

You also loose fuel mileage because the pump is working its arsse off all the time too.

----

Trying to save a dollar in trucking on proper repairs and maintenance of especially that engine .. ALWAYS ALWAYS costs thousands (sometimes tens of thousands) of unnecessary $$$$$ down the road, and a whole lot of regrets.

Thanks for the quick reply Rawze, I will definitely do the test when I get those plugs and see if it’s the injectors, they are all still the original so maybe it’s time to put a new set in. $12,000+ for a new set sounds crazy but it’s not near as bad as if it washed out a cylinder…

[tree98]

You shouldn't need all 6 at the same time.

[Tony]

Mine was leaking pretty bad and turned out it was only 1 injector. So maybe you will get lucky.