Used 3126b engine

[Bigdog]

Does anyone know of a good running 3126b 8yl rv diesel in the Pacific northwest area? The one in my rv has a dusted cylinder and so I need to replace it. CAT wants about $32-34k to replace it with what they called a running engine which sounds like a long block as they will use the external accesories from mine.
I was thinking of just selling it as is, but I can't morally do that, unlike the dealer I bought it from and the previous owner. If I sell it as is and disclose thre problem, then I'll go upside down.

[jwmII]

The way your article is written leads me to believe you have one bad cylinder only. That one cylinder if not to bad might be saved by honing or at the worst boring it to cleanup which might only be .010 to .020 thousandths oversize. A new oversize piston could be used on that one cylinder. This is kind of a patch job but would give you a decent running engine for use until you decide if you are going to sell down the road. Take your time and shop around tho if you want another engine. That engine is quite common and there are a lot of them available.

[slickest1]

If the engine was dusted, wouldn't there be more than one cylinder involved?

[Bigdog]

Just got back from a little jaunt on a boat and train to Denali,so was gone for a bit.
1. Occasionaly it blows dark gray smoke from the exhaust on start up, but only a major puff and then done.
2. notice engine blowby only when at low idle and if you run it up over 800 RPM it won't blow.
3. It uses a minimal amount of oil, Drove to Portland and back a few weeks ago and barely moved.
4. CAT in Fife dropped the pan and checked the cylinders from underneath and also found sparkles in the oil filter and on the drain plug and power drop on all but the dusted cylinder. $1200 bill for that.
It runs ok on the flat, with or without the toad, but slows down and heats up on the hills. I wish there were some easy way to check the high speed fan on these things to see if it's kicking in. On my school bus, you could hear it cut in, but not this thing.

[Jarlaxle]

Bigdog wrote:
It tis interesting that it doesn't use anymore oil than it did 20K miles ago. It actually blows less on startup than before,but there is a lot of blowby. It runs down the road fine, but when you hit a hill you're in trouble and she slows down and starts heating up. I am doing a really better job about downshifting and keeping my foot out of the injectors.
The Cat guy told me it was ok to run it as long as I don't get too far from a major tow truck company.

Does it smoke from the exhaust? If so, when, how much, and what color? What, EXACTLY, happened to the engine?

I just emailed a link to this thread to my uncle (retired heavy truck mechanic, Cat certified), will pass along his thoughts.

[Passin_Thru]

http://nationalpowersupply.com/caterpillar3126.html Has them in WA or Or.

[tinkerer]

If it doesn't burn oil I would get a second opinion. I seen a fairly new Cummins that had excessive blowby. Turned out the owner had installed one of those high performance air cleaners and dusted the engine. Cummins was not going to cover it because of not using an approved air cleaner. Also the Rock and Dirt magazine has a lot of engine vendors. Good luck.;)

[Bigdog]

Well, I guess that didn't work out too well.

[Bigdog]

It tis interesting that it doesn't use anymore oil than it did 20K miles ago. It actually blows less on startup than before,but there is a lot of blowby. It runs down the road fine, but when you hit a hill you're in trouble and she slows down and starts heating up. I am doing a really better job about downshifting and keeping my foot out of the injectors.
The Cat guy told me it was ok to run it as long as I don't get too far from a major tow truck company.

[Jarlaxle]

Honest question for the OP: does it still run? Does it show any signs of catastrophic failure? If so...I wouldn't replace it, just run it and make sure to keep the oil topped off!

[rgatijnet1]

Without knowing all of the details it is tough to speculate what can be done. If the damage is minor to the cylinder walls, it can be honed out. They also make portable machines that can bore out one cylinder with the engine still in a TRUCK frame. I don't know if there is enough access to do that in an RV frame.
In either case, the rest of the engine probably needs to be dismantled to insure that any metal filings, etc have been cleaned out. This involves dropping the crankshaft, etc. This is usually followed with a replacement of all bearings once things are apart. The head may also need to be rebuilt once it is removed.
I had one diesel engine resleaved and it is still a major project even if the engine does not have to be removed. After watching the whole procedure and the tight working environment, I think it may have taken less labor time to drop the engine before doing the work.

[wolfe10]

Correct-- the Cat 3126 (an in-line 6 cylinder BTW) can be sleeved.

Saw an independent company doing it at Mustang Caterpillar in Houston.

But, if more than one cylinder bad, may not be cost effective.

And the total price you were quoted is WAY, WAY high.

[RayChez]

Yes 11178adn is correct. They do have kits to where those 3126 engines can be sleeved.

[11178adm]

yes 3126/c7 blocks can be sleeved they bore the block and install a dry sleeve, a lot of labor involved. check with a freightliner dealer, they have a line of reman engines, I think it is there Alliance brand, that is usually cheaper than genuine CAT.

[J-Rooster]

Hey Jon, how in the heck are you it's been awhile! Call Craig Stensgaard at Food Services of America, Kent, WA. 1-800 562-5317 he just might have one laying around! Tell Craig that Rooster said to call you. Craig and I were at the Bowling Alley where I meet you for coffee about 3 weeks ago. Craig is in charge of both FSA Shops Kent and Everett and some of his delivery trucks do have 3126 engines. Take Care, Rooster