2012 Isx 2350 475 with codes 4726 and 0559

[tree98]

(01-25-2022 )ahrenbenjudah Wrote:  I’ve only ever had issues with the ceramic plungers getting chewed up and being the obvious culprit.

The steel ones fail too!!!

[Rawze]

(01-25-2022 )tree98 Wrote:  

(01-25-2022 )ahrenbenjudah Wrote:  I’ve only ever had issues with the ceramic plungers getting chewed up and being the obvious culprit.

The steel ones fail too!!!

if those parts have more than 400k miles on them then they need replacing. The steel plungers fail just the same as the older style. Only difference is that it takes several more days to destroy the entire engine rather than a few hours... those updated plungers has solved noting towards this issue.

-- As far as one of them not staying up when pressing them in and out.. that is a sign that all the guts need replacing.. and that they are worn out. - its time ti replace the guts.. tappets, rollers, plungers, etc.. and not question it.. because if you thing your going to save a bit of $$$ about it.. then you will loose that whole engine at some point by putting those worn out parts back in.


That thing is nothing to play with.. not one little bit.. it is noting to guess at.. it is nothing to take a risk like that on. - It WILL EVENTUALLY EAT YOUR ENGINE INTO A BOAT ANCHOR if you try to take any shortcuts about it!.. plain and simple!.... I don't care how you think it looks and/or what your experiences in the past have been so far. .. and ANYONE who would tell you otherwise is a complete idiot!.

[ahrenbenjudah]

I am definitely not going to shortcut it. I am going to order up a new head with new barrels and plungers as well as tappets and rollers. The camshaft itself looks immaculate so I think I got lucky on this one. It appears that just an inner check valve crapped the bed on me. I'm going to look at my other trucks closely as well because I don't like boats...no need to have anchors for them.

[Hermjeji]

Look around for prices at a few places. Some dealerships were quoting me a 400% increase on the fuel pump rebuild kit, at that point it was only 200 more for a complete head.

For a 2250 the P/N are as follow:
Tappet(roller) - 4359134
Plunger - 4327258
Gasket (needs to be replaced every time you remove the head) - 2872513
Washer - 3963990 and 3963988

You need 2 of each except for the gasket.

[ahrenbenjudah]

Parts will be here tomorrow. Ordered a new head, comes with barrels and plungers. New tappets and rollers. Gaskets and sealing washers. $2500 and change. Hopefully have it back together tomorrow. Unless more of my drivers screw stuff up like today.

[hookliftpete]

That price is insane. Was about $600 when I did mine about 2 years ago...

[Hermjeji]

(01-25-2022 )hookliftpete Wrote:  That price is insane. Was about $600 when I did mine about 2 years ago...

Tell me about it. In Canada here, last month i asked for the price on the springs and plungers (rebuild kit) it was 183, last week it was 599 (AND YOU NEED 2...). At that point, putting all the other items together, it makes more sense to just get the head for 1900.

[ahrenbenjudah]

I asked how much just the whole fuel pump was and KW told me $4300. And that’s with my decent pricing schedule we get. -shrug- The truck doesn’t make money when it sits.

[ahrenbenjudah]

Well. I put the new head on. Everything back together and I'm still getting a crank/no start. Insite still says commanded pressure is 5k+ and rail pressure is <200.

What is the fuel rail pressure rationality sensor? That reads -1100.

I checked the new head before I put it on and it passed all of the tests that Cummins lays out for inspection.