The Cat 3126 Engine. Know Your Engine. Caterpillar 3126B and 3126E.

This video discusses the Caterpillar 3126 Engine. The engine’s design, faults, and common problems. This video also has a “Destruction of the week” segment.

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33 thoughts on “The Cat 3126 Engine. Know Your Engine. Caterpillar 3126B and 3126E.

  1. Are the 1996 model engines an actual 3126, or are they a "cross-over" engine? I've got a 96 Motorhome with a 3126 in it and am curious.

  2. I have a 98 fl70 with 3126 glow plug light on strut up at fast idle kind of rough step on brake back to slow idle after a minute goes back to fast idle ! Sensor maybe ??

  3. I own a 2000 fl70 with a 3126 in it. The engine has 200000 miles on it. On cold start up it makes a pinging knocking sound. The colder the worst it is it seems like. And right before it stops it has a winding sound. And right when it stops it has like some zipping sound just for a few seconds. With a little white smoke. So from start up to when it stops doing all it's funny business it is like 10 seconds. Then it purrs like a cat😊 So what could that be? Thanks for your time.

  4. Hey thanks for info

    I have a 2003 freigty m2 106 with a 3126 and an Eaton 6spd 106k any recommendations for long turm trans reliability? Or what to swap it to in the event of a failure.?

  5. Great Video, however I have marine application of the 3126 model, do you have any videos on marine uses. There are slight differences.

  6. I have a problem with my cat 3126 I was changing the injector # 4 and one of the bolt falls in to engine and any help with any suggestions

  7. I ve the 3126 in a 2002 bus. 385000kms. been very good engine. change oil every two months 3000kms. wish i could buy a brand new one.

  8. Okay I got one for you I am rebuilding a 3208 when I put the injectors on my test bench and get my precious set correctly when I put The cap Back on I get hydraulic lock it go’s to 4000 psi and it sits at 2 500 psi in the injector and won’t crack why does it not do this when it is installed in the motor
    Nobody can tell me ?

  9. Hey Josh. My name's Criss. I'm in Vegas. Do you or know anyone that might a an injector cup puller for a 3126b I might be able to borrow for a night? I'd be willing to give $150 for letting me rent it.

  10. Hi i got C12 i just fully rebuilt that Eng but oil pressure is stay 15-18 psi @600 rpms when water temp is 185 is this normal oil pressure?

  11. Get a block heater or diesel heater (webasto) to for cold starts.
    Can pull Webastos off of school buses at scrap yard. Will heat the entire block and your interior within a few minutes in freezing temps. Nice hot start ups.

  12. I own a RV repair shop and your videos have helped us a lot. We are having a no start problem with a C7 that I could really use your help with. most of the fault codes pointed to the pump, but after replacing it and bleeding the fuel system we still can not get it to start on its own. I think we are losing oil pressure els where. The coach ran grate, put in storage for two months then would not start.
    Darren 949-292-5744

  13. I would like to ask you a question ?? on the primary filter with a rubber press pump, is that aftermarket?? I don't have that on my 3116… I don't think I have a primer pump on my engine ??
    Next comment:
    There is a larger fuel line with a bracket along with two bolts that hold it to the top most fwd area of cylinder head… just forward of that point is the engine removal piece that has a large hole a chain will fit for lifting…fwd of that is the heavy bracket held by six bolts that supports fan clutch and fan assembly….
    My thinking along with you're pointing out a hairline fracture might exist..?? the area of the right bolt ( 1 of 2
    Looking from front of eng..) that secure the return fuel line flange to the cylinder head….
    So happens that the top right bolt
    Of the bracket supporting fan and
    Clutch bracket taps and threads into the same vacinity of cylinder head…..very close!!!! Might be a weak spot??
    Maybe you could share with me what I might see if I removed the bracket that supports fan and clutch assembly along with the engine lift piece ???

  14. Mine has been a ok motor…expect now when it's cold.. it wants to smoke grey white…and flutter..until you give it more rpms…then it will clear out. When the motor is good and warm it pretty much goes away..until you come to a stop and go again.

  15. I'm considering buying a 1986 Ford L-8000. It has a CAT 3208. If a had catastrophic failure with the 3208 would the 3126 be a reasonable candidate for a swap?

  16. So I'm looking at buying a bus it was just taken out of service last month it has the 3126 with a allison would it be a good purchases?

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