Engine Maintenance Items…

Sept. ’18

Purchased this ’02 Winnebago RV with Cat 3126e engine carried by a Freightliner XC chassis Feb. ’16 and the consignment dealer was suppose to do all the normal every day lube and fluid checks before I drove it off the lot and they assured me they did. Had a good rapport with the tech after visiting several times so although I’m sure they didn’t change oil, or filters, pretty sure at least they checked them. They did miss the hydraulic fluid level in the Jacks & Slides tank, but I found that not to long after and topped it off.

Instead of insisting on a full service check with new oil and filters, I crossed my fingers and just checked things until Sept. of ’17, when I found a shop in Burns, Oregon and had them do a yearly oil change and yearly service for me, along with checking all the fluids and lubing the chassis. Also changed out the fuel/water separator.

What I’m doing every year from now on is change the oil, filters, have the chassis lubed, and every other year, change the air filter. And of course I’ll do any other stuff Cat recommends based on mileage.

The engine is a Cat 3126e, which is a twin to the C7 except the C7 has some enhancements for heavy duty commercial work. Some things I’ve read say that the 3126 needs 19 qts of oil, others say 22 qts (22 qts was written next to the oil filler tube by the Winnebago factory), I’ve settled on 20 qts because it’s easier to buy that quantity AND I don’t get hardly any oil blown onto the front of my toad vehicle.

Here’s some of the info I’ve gathered on this engine and chassis:

Walk around Video: Cat 3126 Walkaround

Another video: The Cat 3126 Engine

Here’s a HEUI video: Troubleshooting HEUI

Oil: Cat recommends 10W-30 or 15W-40 ‘Diesel’ oil because thin oil in this engine (5W) isn’t good for it. I use fully synthetic diesel oil and either bring my own, or ask the shop to order it. It’s OK to go 8,000 miles with a blend, but I like the 12,000 miles I can get with fully synthetic, however knowledge is king and further reading tells me that a Cat will be more reliable over the long run with oil changes that are more often. Between 6,000 and 10,000 miles. And I’m going to do it that way from now on using synthetic…basically to protect the HEUI. My last oil change, ended up with 15W-40 synthetic blend instead of full synthetic. Sigh.

Oil Filter: 1R-1807; Napa 7791

Fuel/Water Separator: 198-6378

Air Filter, assembly: WIX46748; Original 11488003; Fleetguard AH1197

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Waste Gate (if I have one ??):

“The Waste-Gate is a venting mechanism for the Turbo. If it fails, the Turbo can overheat and fail. There is a relatively easy check for proper operation. On a C9, the waste gate is located just behind the turbo (driver’s side of engine). There is a tube that extends down from the waste gate that provides exhaust venting. Insert the end of the tube into a clear bottle with water in it while the engine is running. If you see bubbles, the waste gate is functioning. The only preventive
maintenance recommended for the Waste-Gate is to coat the shaft with CAT Anti Seize lube.”

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Turbo: from what I’ve heard from others, there’s no maintenance to do to it other than make sure the pipes are on it nice and tight, that there aren’t any air leaks, and that the air filter is R&R’ed periodically.

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Exhaust Brake: the brake does need periodic lubrication and this document shows how and where to do that:

Silicone Spray is the recommended lubricant though some insist the Cat branded lube be used.

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Heui System: I’ve done some investigating and it turns out the 3126 model Cat is prone to have the Heui (Hydraulic/Electronic Unit Injector) pump go bad as well as the high pressure rubber hose that supplies it with oil. I’m planning on having the hose replaced with steel if mine hasn’t been already. Here’s a couple pictures I found at this link on line to help id the steel mesh reinforced hose:

This guide was made by Skip426 at this thread on iRV2: HEUI pump oil line upgrade

Here’s the guide to the arrows:

Red arrows – indicate connections on the excess oil dump plumbing that will have to be removed to allow more room to work on the hose.
Green arrow – the return to pan tube; once the fitting is loose this tube may have enough movement towards the side of the block that disconnecting it at the bottom won’t be required.
Blue arrow – is a tinerman nut that holds the electric solenoid section, of the IAPC valve , to the metal shaft that contains the valve it’s self.

IAPC ( Injector Activation Pressure Control ) once the electric solenoid is removed the area of the lower fitting of the hose is way more accessible .”

 

And then there is this about making a new hose: “Regarding hoses, most towns have “Parker Stores” that can provide custom built hoses to fit almost anything you may have. 100R2 rated hose, in 3/8″ diameter for example, is rated for 5,800 psi or > (22,000 psi 4:1 safety factor) and have a sustained operating temperature rating of 215F. For safety concerns, ALWAYS have a “Burst Sleeve” installed on any hose in or around an engine that will have oil’s involved. A burst sleeve is an additional sleeve around the hydraulic hose that in the event of a hose failure will contain and diffuse any spray from pin holes, cracks or complete socket to hose failure. The burst sleeve will eliminate any possible fire due to hot oil spraying on an exhaust system, turbo……. ” — from iRV2 link above, posted by Discovery39.

 

I believe that this is the kit part number I need from Cat 240-0717…note that they have all sorts of inducements…join their emailing list for 10% off, and free shipping if ordering over $100.

And here’s a link to an installation page for the kit: Rubber Hose Replacement

Nov. 2019:

I came down to Parker Dam, CA to stay at a park where Skip426 is staying as he offered to help me check out my Cat 3126e engine. Skip is a professional diesel mechanic and after looking at my engine, it really seems that I have nothing to do! First is the hose I planned on replacing. Turned out that my hose (see picture of someone else’s hose above) isn’t cracked at all. Shows little evidence of stress. Skip feels that it’s a heavy duty hose likely not OEM equipment. Looks different than the standard hose. 

Then I had toyed with the idea of installing a centrifugal oil filter for around $500. To keep the oil cleaner than average. Skip convinced me that just changing the oil more frequently was just as good a method so I’m going to do that instead. 

All in all, a productive trip.