R&R ISL400 Turbo to Intercooler hose ('07 FDDS)

[whalepirot]

Having located the zero boost issue and searched here for how-to suggestions, I've only found a source for the hose, 4" diameter(?). Suggestion is using the (orange) 500* hose, versus blue, lower temp rated.

It's about 6" long and quite visible, but not so easy to access from underneath. Two end clamps, like most similar hoses, secure and seal it at the rigid ends.

Honest, competent diesel techs are a rarity in my locale.

Has anyone performed a replacement that can offer advice on best practice? Thanks in advance.

[Alpine36]

I replaced several in my days as a service tech. Yes, the orange hose is what you want. Typically the clamp was the failed part, especially on PACCAR products. Purchase all new quality constant tension clamps as well, such as these...good luck.
https://ktperformance.net/i-18598122...fe1a6d85ce6b97

[whalepirot]

Originally Posted by Alpine36

good luck.

Thanks.

Good news. bad news. I'm not proud, just learning all about my 1st DP. Being concerned that perhaps the intercooler was the issue, having had the radiator, etc. R/R'd, then I recalled the Pop-WHoooosh sound at failure; like a hose failing.

The 6" long 4" dia. hose fwd of the intercooler tricked me, as it was so pliable, I thought it was ripped. Close inspection after wrestling it out showed it orange and okay.. drat- wasted effort.!

Having read many threads about elbow hoses, I looked and found it, driver-side of Cummins, hidden by fallen compartment insulation (Yaay, another project!)






Pics show rear of coach, then a look inside to the site of the elbow hose, I t was somewhat melted to the metal hoses on both end, not rare, and I finally sliced one end to wrest it from its "home". Yup, blue hose; the lo-temp one and kinda shot!



No part number on it, so I'll have to re-find it in a posting, and order.

[Old Scout]

now about 90S400-16-60409 or 3648-400-MK from Purosil LLC, Corona, CA....800-877-5342 in CA....its the hi-temp orange hose....they don't sell direct, only thru distributors--but you could beg.....

[whalepirot]

Originally Posted by Old Scout

now about 90S400-16-60409 or 3648-400-MK from Purosil LLC, Corona, CA....800-877-5342 in CA....its the hi-temp orange hose....they don't sell direct, only thru distributors--but you could beg.....

I'll skip the long-married joke.


Thanks, I sent a note to Purosil yesterday. Currently pondering if new clamps are necessary as these Lampco clamps look just fine, plus the quality of new anything is a crap shoot..

[Old Scout]

….seems prevailing view is that new clamps are "desirable"????…..agree, you will need to search for good quality replacement clamps.....

[Bruce Anthon]

Since mechanics in your area are difficult to find I would add this suggestion. The Surge / expansion tank can easily be laid to the passenger side by removing the two bolts that are on the left side of the tank. They are located behind the gray frame extension. You will need to cut the zip ties that secure the radiator and block vent tube hoses to the metal upper engine coolant pipe. If more elbow room is needed, you can deattach the vent hoses from the top of the tank and plug the fitting ports on the back of the tank. That gave me enough room to do all the after cooler hose work from the back of the coach. You will definitely need to move the tank when you tackle the dog house insulation repairs. Mine went much easier that way. Let me know if you would like any more info on the reinsulation project.

[whalepirot]

Thanks for that detail, Bruce.


I ordered the hose and two T-clamps from:


Intake Hoses PO BOX 6412, Spokane, WA 99217

Email: admin@intakehoses.com Ph: 509-489-3684



Silicone Elbow 4" ID X 90 Degree - Matte Red - 500F 90AR-400X6M $43.76

Spring-Loaded T-Bolt Clamp for 4" ID Silicone Hoses B9226-0425B $12.72


$20 bucks less than the LA source; clamps in same order, plus they're closer!

[whalepirot]

Originally Posted by Bruce Anthon

Let me know if you would like any more info on the reinsulation project.

I am open to any and all input from those willing to send; here or PM.

Good news:
- The (Spokane) hose supplier is sending all of the order today; great service!
- I reinstalled the lower front hose. Generous silicone spray allowed rotation, sliding, cleaning of dirt (beyond other means) that was needed to properly position the hose on the 4" SS tubes (tight, grimy quarters). The best tool (Lisle?) for large hose attachment is a hook tool, of larger dimension that for radiator hoses.


I'm hoping there was a longtime small leak, explaining/remedying less than expected performance and MPG from the ISL400.

[c_oneil]

Originally Posted by whalepirot

- I reinstalled the lower front hose. Generous silicone spray allowed rotation, sliding, cleaning of dirt (beyond other means) that was needed to properly position the hose on the 4" SS tubes (tight, grimy quarters). The best tool (Lisle?) for large hose attachment is a hook tool, of larger dimension that for radiator hoses.

Maybe I am just misunderstanding this thread or my '05 is different but the access to the 90 deg elbow hose and the short lower hose was pretty easy. I never moved the surge tank. Did you remove the door that covers the radiator stack? This is the area with the door removed.

This is the old blue hose I replaced right behind the aft radiator mount in the picture. You can see the short lower hose just at the bottom edge of the picture.

[Old Scout]

...have no idea what the proper technique is for installing these hoses but would be a bit concerned about using a "lubricant" to ease install....for straight hoses probably not as big an issue but lots of lateral pressure on an elbow if piping is not fixed in position?????...do agree with using new clamps--just to be safe....

[whalepirot]

Originally Posted by c_oneil

Maybe I am just misunderstanding this thread or my '05 is different but the access to the 90 deg elbow hose and the short lower hose was pretty easy. I never moved the surge tank. Did you remove the door that covers the radiator stack?

I simply read, carefully, the suggestion then quickly and easily removed the two bolts securing the expansion tank, laying it to the right. While access to change elbow hose was far easier than the 'wrong' fwd hose, plus reattaching the insulation is made possible. Nothing else was removed.



I am now shopping for the best way to remount that that heavy foam assembly. Residue on the foam indicates the factory used three glue strips,with no mechanical fasteners. My initial search will center on the excellent 3M heavier-duty spray. Hopefully the mattress above won't be so warm after driving!

Originally Posted by Old Scout

concerned about using a "lubricant" to ease install.

Shared concern, but alternatives were few and very difficult, particularly using non-petrol based lube. The 6" hose spans a 3" gap; both SS tubes having a ridged end. I was very careful to center the hose, ensuring the clamps grip outside those ridges. Center positioning was not easy, requiring 3-4 tries within the high-up, grimy area. I'd repositioned the three reinforcement rings (in hose grooves) to the center one; improving hose flexiblility during install, then temporarily squashed the hose to reposition the rings after the clamps were secure.

[Old Scout]

….sure others will have comment but I find that the OEM heat pad absorbs dirt, grease and water over time, making it incredibly heavy....the foam backing deteriorates so even the best adhesive has little chance of hold the OEM pads....appears in 2004, WRV went to a fiberglass molded engine compartment so stopped using metal straps/discs and screws to retain the heat pad in place. Think best solution is to replace the original pad with foil/cotton engine heat shield and use metal strips/discs and fasteners to secure to engine compartment--INHO.....

[whalepirot]

The fallen side's retention disks were missing, which was laying on the turbo hose. I realized, after fixing everything, that quite a lot of cooling air flows from the fan over that turbo hose; parhaps playing a role in its failure.

I considered using the sound blocking, heat resisting deadener sheeting that I've used in a few cars. The adhesive may or may not hold better in this application, IF installed inside the compartment and how well it would survive the radiated heat.


Yes, that factory foam+ is heavy, but I reglued with generously applied 3M 90 and installed 18g metal angles as a replacement for the disks. We'll see the long-term result, but 40psi boost is way mo bettah than 0!