Saturday, June 24, 2006

Cat Diesel-3116 drops a valve/Head Removal

Cat Diesel 3116 Models seem to have a problem with exhaust valves staying in one piece. Cat Diesels are built tough but do have a few weaknesses, the exhaust valve typically on #5 cylinder.

This engine was in the shop running and all of a sudden the top end started knocking, Houston we have a problem!

I removed the rocker arms and found a bent exhaust push rod on #5 while we got lucky and the injector tip was not damaged.

So off with it's head! I will keep posting as I go disassembling our 3116 Cat Diesel


Anonymous said...

Hi John, my school bus stopped running. It was doing great, then just ran down on power and stopped. I have changed the primary fuel filter, but not the secondary one yet. How likely is it for the secondary one to block fuel flow? I don't know much about diesels. Any suggestions? (by the way, it is a 1990 Bluebird with a GM 8.2 liter turbodiesel).

Thanks - Stephen in Texas

John Whelan said...

Hi Stephen,
Most definitely change both filters and check your air filter. There's a rule of thumb for diesels to run, you need air and fuel. A fuel restriction will cause your diesel to bog down especially under load.

Anonymous said...

John, thanks for your quick response!

I changed both filters; after it did not start, I checked for fuel flow. In unhooking the fuel line between the primary filter and the engine, I was able to blow air back through to the tank, therefore establishing that there is no flow restriction in that part of the system.

However, when cranking the engine, there is absolutely no suction at all on the open end of the line going to the engine. So, is there a need to somehow prime the fuel pump, or is this an indication that there is a problem with the fuel pump or something else? Thanks from a guy who is learning more about diesels than I ever planned to.


carl said...

hey john thanks for your info found # 1 injector running cold . is there more to setting up # 1 injector then the rest ??? [any extra tools] and looking to install a 9 are 10 speed in a 94 gmc topkick has a six speed now have rt1409 roadranger is the bell housing a #2sae ?? any help would be great thanks and keep up the good work ck

carl said...

14609 roadranger

John Whelan said...

Hello Carl,

The #1 injector has to be timed but not synchronized [the #1 synchro adjustment is factory set]
You will definitely need a compatible bell hsg. for installing a 9 speed Roadranger. I'm not sure about the bell hsg specs.
I'm wondering about the clutch linkage and how it will adapt?

DuitOrelze said...

We are in the same deisel pergatory as Stephen and are waiting to hear what you say to the prime issue. We have two fuel lines going to the pump. One goes to through the spin on filter. The other one goes through a water seperater. Can we hook up some kind of pump aparatus on the fuel line going to the water seperater and prime the pump? There were issues with the water seperator. It had been bypassed and I re-installed it. It ran for a couple minutes and then died. There is no fuel to be seen when I crack any of the fuel lines. I bypassed the water seperater again and still no fuel and it won't start. Please help me figure out how to prime the pump.
Mike Skjold

burnthefatjourney said...
This comment has been removed by the author.
John said...

The easiest method I would recommend is to use shop air and stick the nozzle into the fuel tank and seal it with a rag.

Prime both filters.

Before you pressure it up crack a line closed to the tank and keep going until you reach the fuel pump. Most 3116 engines have a priming pump but I guess it's an option.

I could never understand why a diesel engine came from factory without some kind of priming pump.

Try that and do a search on my blog for: cat 3116 fuel system schematic
enter this term into the search box [top left hand corner] that will give you a better idea on what the fuel system is made of.

Anonymous said...

Hi john what a great site. you have helped me so much with the overhead adjustment on my 170hp cat 3116. The motor is in a 95 chevrolet kodiak rollback tow truck and has the factory 5 speed. I want to up grade to a 9 speed. Will that work with my 3116 and if so what type of gear box should i look for. I know that i will have to shorten the drive shaft. Im just not sure if it is a good idea. If you could give me a few pointers that would be great. Thanks for all your help in the past,you have saved me so much time and money. Thanks again, Brian

chuck said...

How do you diconect the fuel rack from the pump to remove the head

John Whelan said...

There is a spring clip that fits over the metal tube from the head to the governor.

Remove the clip and slide the tube into the head, it may be stiff from the o-ring that seals it.

The tune up kit has rubber covered vise grips, I use rergular grips and carefully clamp on and wiggle the tube back and forth while moving it towards the head side.

Once out of the way there is a c-clip that secures the pin connecting the rack arm.

Remove that and slide the pin out.