CAT C7 Engine Maintanence

One thing that I neglected for too long was the "Dryer" or Drier" filter/rebuild kit....its the thingy that does the hissing sound and keeps your air system from getting moisture in the system.

I generally change my Fan belt every few years but my access on my Cat is relatively easy(side radiator). I check my hoses whenever I have the engine cover open. One thing I recently came across was a large tear in one of the Turbo Charger boots....which can cause all sorts of problems so do check all the connecting boots on your Turbo(access from under bed, I'm guessing).

thanks

I am in sort of the same situation as you we own a 2006 CAT C-7 from new.

After being towed, A real eye opener, on our last trip and a lot of research I believe I am due for a radiator and air cooler removal and cleaning. while out all new belts and hoses, new regulators (thermostats) air filter and air dryer also the fan hub bearing will be replaced with a grease-able one. belt idler bearings replace, water pump checked for end play ETC.

Over the years I did air dryer change outs along with air filter trans fluid and filters ETC. All to say I thought I was doing good with maintenance. But I was avoiding the stuff behind the rear radiator.

Hope you have changed out your air filter. also your 2004 has the grease-able fan bearing. Check your "blow-off" oil tube make sure the end is below the bottom of the radiator.

I am going over this motorhome chassis head to toe

Stop by in 4 weeks and we will do both together. LOL

PM me if you want to discuss more about what I found online about all the weak points on our rigs.

Thanks Joe

JCat wrote:
coolant changes every 2 years.

If you have the book for your engine and your chassis manual, it should give you all the information you need. One thing you are probably doing too often, assuming you are using an approved Cat ELC coolant, is changing that every 2 years. Cat ELC (or another that meets the specs) is good for 6 years or 600,000 miles. Of course it would be extremely rare anyone put 100,000 miles per year on an RV, so usually the change period on that would be 6 years. If you're at the point you want to change out belt and hoses, it might be a good time to put in a new thermostat and pressure cap.

Fuel filters (two of them usually), air filters, oil and oil filter, the air system's dryer desiccant kit, all the grease points (there's probably a lot of them), transmission filters and fluid ( you can extend fluid changes by using the recommended Allison Transynd fluid (assuming that's the transmission you have). If you have front oil bearings, it's cheap insurance to do those every so often...but it does require a large torque wrench based on the ft-lbs needed on the lugs. I'm probably missing things off the top of my head, but those are the biggies I pay attention to (along with my generator).

I'll be checking those turbo boots on mine!

When I had my radiator replace with a steel and copper the system was flushed and Cat ELC coolant was installed. That was 6 years ago so I just pull a sample and sent it in to Peterson Cat and it came back still good.
JR

STS, I can drop my RV off for you to a 2 for 1 !
LOL

Yes I ran into the oil cooler issue in year 2 of ownership, when it overheated due to oil caked on the trans cooler and radiator, that was fixed then, and every year I give both of them the simple green treatment.

JCat wrote:
I have a CAT C7 with 60k miles on it, 14 years old. I do oil (synthetic) and coolant changes every 2 years. I have never changed the belt or the hoses and was wondering when I should replace them ?

And is there anything else I should replace ?

Thanks

Pre-script edit: I just realized your coach is in your sig so, disregard my first sentence below.
JCat,
You don't say what model/year coach your C-7 is in. 60K on an original set of belts, both the serpentine and the V-belt is a ton of mileage and years for them to exist in that kind of operating conditions. Needless to say, they build them pretty good but, they still need replacing. It's too bad that Photobucket ceased to allow free picture linking because, I just finished doing all of what you're thinking about. If your coach is a rear radiator version, which something leads me to think it is, yes, it's a real pain in the a$$ to pull both the radiator and CAC to gain access to all of what's needed for this large type maintenance project in front of you.

I've got a zillion pictures of all the steps and what's revealed in each step. I'm 65 years old and just did all of it. While it's a pain to pull both of them, it's not the end of the world. I've done it TWICE. The first time, about 6 years ago, it was done to actually replace the aluminum/plastic radiator for a copper brass one. At that time, with 40K on the clock, I tried to replace the infamous fan bearing. But, due to very difficult Allen head screws not wanting to be removed, I gave up and put it all back together.

Well, fast forward 5 year and, 42,000 more miles. I decided to pull that radiator and CAC again so I could do what it takes to replace that fan bearing. Little did I know it, my water pump had given up the ghost, right IN THE GARAGE, at home. So, I needed to replace that while doing all the other stuff, hoses, both belts, regulators (thermostats), air cleaner, and maybe some other stuff.

If you'd like to PM me, I'll answer back with my email address and, as many photos of the front of that engine and what to look for in terms of replacing stuff and other info as you may want. Depending on which air dryer you have, you'll need to service that too. If your dryer is the same as ours, you'll need to remove it to service it. The DQ6026 is the service kit, found on ebay, Amazon (sometimes) and other places.

Be prepared for sticker shock on the radiator hoses. I got all mine at a local Freightliner dealer and, it came to about $315 for all of them, plus the two thermostats, and gasket. My water pump came from Ebay and was brand new at $90 plus $15 for shipping. That was one seriously great deal 'cause most others were well over $250. Anyway, if you need advice on how and what to do to get the rad and CAC off, just ask.
Scott


Posted By: seeing the sights on 03/15/18 03:55pm

I am in sort of the same situation as you we own a 2006 CAT C-7 from new.

After being towed, A real eye opener, on our last trip and a lot of research I believe I am due for a radiator and air cooler removal and cleaning. while out all new belts and hoses, new regulators (thermostats) air filter and air dryer also the fan hub bearing will be replaced with a grease-able one. belt idler bearings replace, water pump checked for end play ETC.

Over the years I did air dryer change outs along with air filter trans fluid and filters ETC. All to say I thought I was doing good with maintenance. But I was avoiding the stuff behind the rear radiator.

Hope you have changed out your air filter. also your 2004 has the grease-able fan bearing. Check your "blow-off" oil tube make sure the end is below the bottom of the radiator.

I am going over this motorhome chassis head to toe

Stop by in 4 weeks and we will do both together. LOL

PM me if you want to discuss more about what I found online about all the weak points on our rigs.

Thanks Joe

Joe, that statement is not necessarily true. When CAT created the C-7, they also eliminated the "lubeable fan bearing" due to the fact that they found out many folks weren't lubing them. Our coach, an '04 Itasca Horizon 36GD with the 330HP C-7 CAT, has a chassis build date of 10/03. I've managed to find other CAT owners that had build dates of 8/03 and 9/03 and theirs had even had 3126 versions with a non-lubeable fan bearing. So, at this point, we're not sure just when CAT decided to stop installing the lubeable ones.

Scott

Scott, Small world......... as I was going to reach out to you soon regarding my upcoming project. I found your posts on another board. First I am going to get my codes pulled to see what happened on my way down south. Then in the garage up on blocks. Yes thanks for the correction about the grease-able fan bearing. Again hope its ok to get in touch with you about my project. Thanks, Joe

seeing the sights wrote:
Scott, Small world......... as I was going to reach out to you soon regarding my upcoming project. I found your posts on another board. First I am going to get my codes pulled to see what happened on my way down south. Then in the garage up on blocks. Yes thanks for the correction about the grease-able fan bearing. Again hope its ok to get in touch with you about my project. Thanks, Joe

Absolutely no problem contacting me on this. I'm no expert by any means. I've just done what some would call some "deep" maintenance. If you've ventured over to IRV2, you'd find my post:

http://www.irv2.com/forums/f124/ok-cat-people-need-some-technical-assistance-here-374555.html

In that post/thread, you'll see just what things look like when digging into the back of our coach. One thing that's vitally important here. That radiator is approximately 5 years old, plus or minus. Just prior to installing it, I modified the frame of it, so more air flow could take place. The corner gussets were solid plate steel. Well, when you add up, all the square inches of all EIGHT corner gussets, you'll find there's quite a bit of non-air flow area.

So, I plasma cut, as much out of all 8 of those corner gussets as possible and, still retain their strength. One more thing. I also re-routed my blow-by tube to the very back of the coach, right next to the exhaust tip. So, what you'll see in the radiator fins in terms of dirt/debris/hay/grass/ a "Rat"(yep, a small Rat) and a few other items, was accumulated in the last 5 years and about 42K miles.

Contrary to what some believe, It's virtually IMPOSSIBLE to clean any section AT ALL, of my radiator and CAC while both are installed in the coach. Maybe some can get to thiers but, not mine. So, while all this was out this time, I disassembled the radiator frame, cleaned things up, blew out the fins with my small pressure washer (did the CAC too) and put it all back together.

So, again, feel free to contact me at any time.
Scott

Yes, there is a lot more you should be doing. If you send me a private message with your email, I will send you an excel spreadsheet with the complete maintenance required and how often it is due, along with the manual that describes all of the maintenance items.