cat dozer wont start

[CATCRACKER]

i put a new fuel filter on it bleed the lines cranked it up ran ok. let it sit over night and i had a hard time cranking it. now it wont start at all. when i replace the filter i filled the housing up with diesel service fuel additive. i have bled it several times at the injectors and i am getting fuel at all injectors. i used starter fluid, soak a rag in gas held it in the air intake without it even trying to start. it has always been a hard starter due to low compression i think. it ran perfect until i changed the fuel filter. I am at a loss. how hard can it be to get the air out? should it have started on the either?



question: can i get air in the lines and still get fuel to come out at the injector lines and still not crank. its getting fuel in the engine. it ran fine until i changed the fuel filter so assume the pump is working. why wont it crank of either if its getting fuel to the engine? thanks for the help it a 87 cat d3b

 

[CBari]

Did You Try To Start It Off Of Either. I Also Have A D3b And It Can Be Tough To Restart If It Is Run Dry. If One Of Your Injector Lines Or Any Line In Your Fuel System Is Not Tight It Will Let Air Back Into The System. Start It And Run It Off Of Either Till It Picks The Fuel Back Up.



I Also Made The Dumb Mistake Once Of Running It Dry And Adding 5 Gallons And Couldn't Get It To Start Because Of The Slope The Dozer Was Sitting On, Was Keeping Fuel From Entering The System.





Good Luck

 

[CATCRACKER]

it wont run off of either

 

[n7gxz]

On my '54 D2 I have to blead the system starting at the filter housing and then move up to the injection pump and then finally to the injectors. On advantage that my D2 has is that I can run it on the pony and not have to crank it on an electric starter.



Kevin

 

[OKish]

where are you located? is it been kinda cold there too? maybe heat it up or plug it in somehow. might just need a little heat to bump up the compression and make it crank a lil faster.

 

[MMiller]

Does it have a hand priming pump?



Does the starter spin the engine as fast as it usually does?



Have you left the injector lines loose while cranking the engine with the starter? Does fuel squirt, I mean really squirt out?



What engine is it, and 3204? I haven't worked on any D3s, D4s were about the smallest I've been around.



Does the fuel system have a primary filter, or water separator, or a metal housing with a screen in it? Have you opened it up lately?



I had a 3208 that ran out of fuel(almost identicle setup as a 3204), I had a little fuel at the injectors, and it would squirt a little during cranking. Kept pumping the hand priming pump(after the customer spent a day trying to prime it) and kept cranking, and eventually it started to fire and I kept closing injector lines as they started spraying fuel, then it ran.





Michael

 

[Greenleaf]

Man, how I love my cranking engine starter

 

[cojhl2]

and still not crank

I think you must mean will not start. . It sounds like it's cranking.

 

[cojhl2]

Man, how I love my cranking engine starter

They were the best for sure. I never had one of those fail to start.

We alwasy called them a "Starter motor"



Many Cats in the farming sector were converted to direct but I always thought that was a mistake. I love the old starter motor

 

[CATCRACKER]

yea starter is fine. what has me really perplexed is that it wont even fire up with either. one guy told me his truck would run on either. if the engine is sucking air somewhere would that keep it from trying to fire on either? i went out the other day replaced the filter again bleed everything cranked awhile and then poured the either to it to no avail. how can i still have air in the system if i am getting fuel at the injectors? and if i am getting fuel and air and either in the engine why wont it crank?

 

[Mog]

If it is getting fuel while cranking the it should be blowing smoke out the stack while you are cranking. I had a customer pull their wheel loader (3204 engine) into their shop one day and change the engine oil. When they went to start the engine it would not start. It would smoke but not fire at all. After checking out everything I found the head gasket blew out between number two and three cylinders. Their is not enough cylinders after two cylinders loose compression for the engine to run with the loads of the transmission and hydraulic systems.



Just something else to think about.

 

[abrankod]

The fact that its not even making any starting/knocking noises on ether means that you dont have compression to start. You need to check your batteries and assure that the engine is turning over fast enough. 100rpm is the general rule for a reliable start. Just because its turning over, doesnt mean that its generating the heat necessary to initiate combustion. Also, as pointed out before, if the injectors are firing but there is no combustion, you should be seeing white fuel vapor coming out of the exhaust.



A quick trick you can try is to forego ether and stick a hairdryer or heat blower gun into the intake to supply some nice hot air.



good luck,



Daniel

 

[CATCRACKER]

got it started needed to spin it faster! i made my own compression release (my hand) this helped some along with a hot battery. i am glad it was not the head gasket thanks for all the help. . by the way it was smoking white out of the stack so i knew it was getting fuel. i just needed more cranking speed.

 

[cojhl2]

Cranking spped is the hardest problem to diagnose on a direct start diesel. The cranking motor must turn the engine at least 200RPM for a chance to start.



When they crank slow it sounds like everythiong is ok but as you found it isn't.



The reason CAT used a gasoline starter motor for years (even after the machines carried a battery for lights) was becasue electric motors with reasonable size could not provide enough cranking speed.



The white smoke indicates fuel in the combustion chamber as you said, but black smoke indicates there is some burning of fuel.



Glad you found the issue,, now probably the cranking motor should be rebuilt.



When you said you released the compression by hand what did you mean? I am not acquainted with a D3. Last Cat I worked with was a D6 9U. You had to release the compression to get the starter motor to initiate big engine rotation. When these 9Us were converted to direct start you did not have to release the compression.

 

[MMiller]

When you said you released the compression by hand what did you mean?

Yeah, what he said???

 

[CATCRACKER]

i covered the air intake so very little air could enter the engine which increases the rpm speed of the engine b/c of lack of air to compress. then you pull you hand away from the engine similar to a compression release.

 

[cojhl2]

That's a real hoot!!!! I would never have thought of it! I applaud your initiative in thinking of it.



Can always learn something that's for sure and I just did!!