[randyc]

I own a 2000 Pete dump truck with a 3126B Cat in it. I was recently asked by the mechanic that does my work if I had ever had an "overhead service" done on it. I didn't even know what that procedure involved and why I should or shouldn't have it done. I've put about 200,000 miles on it in 3 years. It has a total of 505,000 miles on it. Can someone explain what an "overhead service" is? I have noticed lots of power loss in this truck and have already addressed anything else it could be as well as being hooked up to the computers at the Cat house and was told that everything was in good condition. Sorry I sound so stupid but I'm just a driver.

[Orangetxguy]

Originally Posted by randyc

I own a 2000 Pete dump truck with a 3126B Cat in it. I was recently asked by the mechanic that does my work if I had ever had an "overhead service" done on it. I didn't even know what that procedure involved and why I should or shouldn't have it done. I've put about 200,000 miles on it in 3 years. It has a total of 505,000 miles on it. Can someone explain what an "overhead service" is? I have noticed lots of power loss in this truck and have already addressed anything else it could be as well as being hooked up to the computers at the Cat house and was told that everything was in good condition. Sorry I sound so stupid but I'm just a driver.

It's a "tune up" for your injectors. It helps fuel mileage, eases that little rattle you here coming from Miss Kitty, and maybe even stops some of the shaking while you sit and idle.

Usually runs about $275.

[randyc]

I recently had the injectors replaced because of bad o-rings. Would the service still be beneficial?

[Kranky]

An "overhead" on a Cat motor is a valve adjustment and Jake brake adjustment.

.

[Fredog]

I have mine done once a year, it usually costs about 300 bucks, like Kranky said, they adjust your valves and jake, they also will see if you have a loose or leaking injector which could save you thousands of dollars if they catch it before it lets loose., so to answer your question YES, you should have it done.
KW recommends every 250,000 miles

[heavyhaulerss]

Originally Posted by randyc

I recently had the injectors replaced because of bad o-rings. Would the service still be beneficial?

if what you say is true. the overhead would of been done after the replacing of the injectors. if this was done within the last 100,000 miles I don't see a need to redo a overhead

[jasontherock]

I have also heard that this needs to be done. I saw a sign outside my local cat dealer for a "valve adjustment" I posted the flyer below. Is this same thing as an "overhead"?
Thanks

[Fredog]

Originally Posted by jasontherock

I have also heard that this needs to be done. I saw a sign outside my local cat dealer for a "valve adjustment" I posted the flyer below. Is this same thing as an "overhead"?
Thanks

yes it is, and if they are giving a free oil change, I cant get there fast enough, a dealer oil change usually runs close to 300 bucks

[BanditsCousin]

I think KW may recommend it at 250K on a Cat, but 500K on a Cummins.

[bob h]

Originally Posted by heavyhaulerss

if what you say is true. the overhead would of been done after the replacing of the injectors. if this was done within the last 100,000 miles I don't see a need to redo a overhead

On an EUI engine (ISX, C15, S60, etc) the valves SHOULD be adjusted when injectors are replaced... because the rocker arm shafts are removed to replace inj's. This 3126 is a HEUI fueled engine and does not require removal of rocker shafts to replace inj's, therefore the valve adjust was likely NOT done during this service.