3126 cat

gearjammer_2000 · Dec 10, 2004

Hi folks I am interested in hearing from people that own a 3126 cat engine and have had problems with them expesially if the have dropped a valve. I am on my third engine and have dropped a valve in each case i also know of at least three other people that have had the same problem. several of us have been talking to an attorney and he would like us to find out if other people have had the same problem with the idea of a possible class action lawsuit. If you have had this problem please e-mail me and list the facts and your interest if any in being included in this class action. my e-mail addy is [email protected]

Searge · Dec 10, 2004

I have a 2003 FL80 with a CAT 3126. Have over 310K miles on it. Going to have my first valve adjustment done on it during my Christmas break.

raceman · Dec 10, 2004

I have two of them and although they dont have a lot of power they are going strong. I did have some pretty extensive problems on one at 220,000 but I do not recall valve being a part of it, I will look back and see. Mine are doing well one is coming up on 400,000 and the other just passed 300,000. Have had oil pump problems but nothing else. Good Luck What year is yours that is being such a problem?

RaceMan

---Why Hug a tree when you can sit on a Diesle---

davekc · Dec 10, 2004

I forget what years were involved but there was a recall on the oil pump for certain years. You can call Cat and they should be able to tell you if your motor is a canidate for replacement.
Davekc

raceman · Dec 11, 2004

Thanks Dave. I did check into that and I bet you can guess where mine fell out.

RaceMan

---Why Hug a tree when you can sit on a Diesle---

gearjammer_2000 · Dec 12, 2004

I know of at least 4 trucks 98,99, and two 2000 models that have the same problem my first engine broke a valve a 298000 miles overhead is always ran at or below 100,000 miles and all other maintence is done at or before cat specs. frankly I think the 3126 is the biggest piece-o-##### ever produced for a commercial truck, wish I had a cummins but to get back to it I am looking for people with the same problem for a class action lawsuit i personally know of 6 engines with 3 people involved and have talked with several others in the expediting industry with the same problem I just never got their names I know that this is a known problem with these engines I just have to do the legwork to get enough people for a class action

kempers_gramp · Dec 21, 2004

I have a cat 3126 with about 210k on it. I have had it only for a short period, about 20k mi. It is a 2003 FL80. So far so good.
I unfortunately am unfamiliar with the valve problems with these engines. If someone could please fill me in on them, it would be greatly appreciated!
When I asked a service writer, at a Freightliner dealership, what I could do to extend the life of the engine, he chuckled, looked at his mechanic, repeated the question to him, and chuckled again.
The mechanics reply was this, and I quote, "they are junk, be happy that you have'nt had any problems worse than what you have, and if you believe in God, Pray.........Alot!" He then went on his merry little way.
Then when I told the service writer that I had not touched a drop of oil in over 10,000 miles his eyes opened wide and his jaw nearly hit the counter.
Sure made me feel comfortable.

What are the adjustment periods for the valves? How much does it cost? Where would you suggest I have it done?
Is there anything to pay specific attention to that may set off a red flag?
Any other input is appreciated.

Thank You!
Kempers_gramp.

davekc · Dec 21, 2004

A good Cat dealer should be able to do it for around $200 to $250.
Most recommend around every 100,000 miles.
You will get some miles out of them if you take care of them.
We had one that went to over 900,000 before a rebuild and my current kw is at just about 400,000. So far no problems, except had to replace idler pulleys. Bearings went bad in them. $300.00 repair in indy. Also replaced alternator at 300,000
Davekc

Larry · Dec 21, 2004

My Cat 3126 has about 425,000 miles on it. It uses less than 2 qts.of oil every 9,000 miles. We keep the FL70 tagged at 26,000 lbs and do not exceed 65 mph running about 1700 rpms. I keep hearing horror stories and am told to expect BIG problems. So far I have no complaints with this engine, although I would like to have more horsepower in the next truck.

Drive Safe.

raceman · Dec 21, 2004

I have posted earlier on this subject and I want to follow up. If you talk to 100 drivers they each will have an engine and a tranny they love and they will each have an engine and a tranny that is just garbage in their mind. I dont think CAT went out of their way to build trash in the 3126. If you take care of anything you can nurse them on forever. Do your PM, do your PTs put good products in them and they do pretty well. I can tell you one thing that I do think makes a difference on those and it is the filters. Use the CAT filters. They cost a bit more but it they do filter better. When I have been in with CAT Filters on nobody has ever questioned anything I said or asked for. I had NAPA filters put on once because there were no CATs and my next stop at Freightliner, the mechanic told whatever happens happens. You are not doing what you were told to do and nobody is going to stand behind this. The CAT is just a better filter and luck or not I pay for them everytime oil change. I change the oil very 6000 to 7000 miles, I make sure the valves are adjusted every 80,000 to 100,000 miles and both of mine are meowing like the CATs they are. Well kittens they are. Take care of it and it will run for you.

The Owner formally known as RACEMAN

davekc · Dec 21, 2004

For what it is worth, you can use Baldwins filters as well. I ran a fuel pressure check and it was the same with Cat verses Baldwin
The Baldwins are a little cheaper.
Hope that helps someone
Davekc

rhughes · Jun 6, 2016

I have a 98 Freightliner with 3126 cat and I am getting oil in the coolant reservoir any ideas?

davekc · Jun 7, 2016

rhughes said:
I have a 98 Freightliner with 3126 cat and I am getting oil in the coolant reservoir any ideas?

Confirm that it is actually oil and not fuel. Internal gasket or head gasket failure would be my guess if actually oil. Can also pull the dipstick and see if that is a milky color as well. If it smells like fuel, then likely a injector cup leak or crack which is common on Cats. Either way, you are going to have a good repair bill. Whole cooling system will need to be decontaminated once repair is complete. We use to use Cascade to clean them out when that happens.

Cat man · Nov 4, 2020

Recently I've bin hearing a lot of trash talk about the 3126 but mostly from people buying the school bus for cheap camper conversion. Not from people who know the truth I worked for cat for 20 years and have owned my own diesel business for 10 years now I've done maintence on 1000s of 3126 engines they are one of the most reliable diesel engines ever made anywhere most engines with regular maintence will see 1000000 miles before a rebuild. Usually lazy cheap owners blame others for poor maintence

Cat man · Nov 4, 2020

All though I will admit cat reman heads are not what they used to be and parts prices have gotten way out of hand hell even the spacer plates are all out of wack out of true and head bolt holes don't line up lol

rksalumb · Nov 13, 2020

Well, after 17 years I have my first Cat engine failure. Cat shop told me it has #5 cylinder miss. This was after testing injectors to find they are ok and even swapping 4 & 5 to see if the miss followed. The engine has lots of blow by too. Cat says cylinder is probably scored and will need rebuilt or engine replaced. They have not pulled the pan to see for sure what is going on.