Caterpillar 3126b engines

We have a 02 DSDP with the aforementioned 3126 with a little over 92,000 miles. No significant issues. Cat is still maintaining them but there are out of the OTR business right now.

I have a 1999 3126B with only 85,000 on it. I run Amsoil and change about every 10,000 miles with no problems yet. It takes me where I want to go whether it be in the Rockies or down to Florida. We get 8.5-10.0 mpg depending on driving conditions. If it has been taken care of, it should give you many miles of happy camping. Best to you on your search.

I have a 3126E Cat in my 2003 DP.Superb engine. I've had Cummins 903's in a commercial fishing boat and sold it with over 5,000 hours on them when I sold the boat and they ran 24/7 for weeks at a time, naturally aspirated V-8s, great engines. Also had a Mercedes diesel, didn't care for it too noisy. Now also have a Cummins 5.9 in my 2003 Dodge, absolutely a masterpiece of a diesel engine! You won't find a better piece of equipment than anything CAT puts their name on. Great company.

106,000 miles on our '06 Phaeton with a C-7, so far just normal maintenance to the engine proper. Have had fuel line problems at the fuel tank, a loose fan belt and a burned out exhaust elbow, but those are Freightliner items I believe.

129K on our 3126 and a look back through the service records shows only regular Mx items and an oil leak 20 years ago.

charlie good time wrote:
I have always respected Caterpillar an Cummins Diesel engines but since we lost a rv totally to fire we are looking for a replacement .Some are powered by the above mentioned Cat engine an reading different Fotums an various other places i get feeling this is not a good engine an some will even say avoid it.Anyone have personal experiences? I am talking about 1998-----2003 year production engines.

Charlie,
Anyone who even hints that you "run away" from any version of a CAT is clueless. In the zillions of diesel powered RVs out there, especially in the year/era you're speaking of, there's many, many CAT powered ones. And, that includes the different versions of the 3126 and the C-7, C-9, C-13 and others. CAT simply dropped out of the "Over the Road" engines a while back due to the fact that, it didn't want to hassle with the emissions part of it.

There's more to that story than that but, that's the basics. The 3126, just about any version of it, is a great engine. It, just like the C-7, was not only used in the motor home industry but, in a few zillion over the road trucks too. The C-7 has followed in its foot steps only with better refinements. The "HEUI" pump (main fuel injection pump) was used on the later 3126 versions but, was refined for better and higher pressure out put on the C-7 versions.

There's some great reading on the refinements of the C-7 units out there. The C-7 was also used in fire trucks across the nation and has worked outstanding in that application. Now, there are instances of failed HEUI pumps, here and there. But, as I've explained to many, many folks, when you take in to account the massive amount of those engines produced and, the amount that has had any issues, the ratio is seriously small.

Not to mention, Cummins has had its share of issues too, with various versions. Wrist pins come into mind. Cracked blocks also seem to be in the back ground on some. Again, of the few zillion of them produced, how many had those issues?

I've got one friend in particular, who's tipping the scales at 126,000 miles on his '01 Winnebago Journey DL, with the 3126, without any engine issues other than one exhaust gasket issue. Our coach, an '04 Itasca Horizon, 36GD with the C-7 330HP version, presently has right at 60,000 on the clock and, purrs like a kitten, for a CAT that is. We hover in the 7-8 mpg range. And that's towing 6,500 lbs. of '11 GMC Sierra Extended Cab 4x4, carrying an '08 Honda GL 1800 Goldwing, on top of a Rampage lift.

Our engine, is the first version of the C-7 and, does have certain ACERT properties. So far, in the four years of ownership of this coach, and that engine, I can only talk GOOD about it. I've been in there and replaced belts and other maintenance items, nothing that you wouldn't replace or maintenance on any other diesel too.

So, if you find a coach and, you like the floor plan and all else, but it has a CAT engine, 3126 (any version), C-7, C-9 or the larger CATs, you'll have no issues. Good luck in your search.
Scott

I just read a very good history of engine ---enginebuilder.com
It does seem Cat had some growing pains with that engine.Article mentioned noise was even lowered in 1998 when 3126b was introduced an was a good engine EXCEPT if a high pressure leak developed in head fuel would get into engine an that is not a good thing.That was corrected in next generation of engine that was known as the c7 buy putting supply line outside of engine.So i feel a cummins (case tractor
engine is a better choice.But there might be some problem lurrking in theres also an would welcome coments on them also.

so are the before 2004 Cat the inline injection pump motors? Still ones we can work on. I am pretty familiar with Bosch inline mechanical pumps.

It's the 04 and later (Acert) engines that are not as good as the earlier years. Basically, the bigger the Cat Acert engine, the bigger the problems. The 04 and later 3126 is called a C7. I had the 3126B in a 98 Beaver and it performed well in a coach that weighed less than 30K lbs. The 3126 is a 7.2L engine while the Cummins can be the little 5.9L ISB or the bigger 8.3L ISC... both good engines.

Our destroyed had a Cummins(case tractor 505 cu in 8.3 l an was very quiet with both doors closed at bed room an bath also.Fire started in 12volt wires in front on driver side while ideling an waiting for fuel.Really dont know cause.But have 4 units we are looking at an 2 are Cat powered