I can't say for sure but I probably got to buy a "non running" 212 grader because the owner didn't know the function of the compression release. I made the deal over the internet and when I arrived to pick it up, in the conversation with the owner he said he had only owned it a short time and the one time he had tried to start it (by rolling down a long driveway) he had been unsuccessful.

First thing I noticed looking at the machine was the air filter was removed, his can of starting fluid was still sitting right there and the decompression lever was pulled out in the decompressed position.........I didn't have the heart to tell him what the trouble was. At the time I couldn't be sure anyway but as soon as I got it home I pulled it off the trailer, popped the clutch and started it.........with the compression release in run of course.

It was probably a good thing he couldn't get it going, it had no oil pressure showing on the gauge and that turned out to be accurate.

Things get a bit confused with so many different levels of experience,as well as a regional term or name thrown in yet to.Easy for miner bits of information to fall into the cracks. I think people digging into your vast knowledge need to be thanked. So thank you all for the knowledge shared so freely.



But this is reminding me of a similar incident with my the D6,9u. I had changed fuel filters many times without any drama. But this one time I spent better than 1/2 day getting it to prime. After air to pressurize the fuel through the filters and bleeding 3 or 4 times, I might have been ready say it would never run again. Went on the scavenger hunt to find the Cat tool for bleeding the pumps as always before just loosening injector lines had been enough.From what has been said I realize this pump is different,but still one very little detail could well be the key to success.

"Old wrote:

There isn't much to see if the lever and shaft are removed. Just a short stub shaft sticking out from the head with a keyway for the coupling. The actual spring loaded detent/plunger device is under the valve cover about midway in the head.

Shaft would need to be turned 90 degrees counter clockwise viewed from the seat to go from start to run position. That would put the keyway in the 6:00 o'clock position.

Yea the 9's are allot different, I was thinking of the shorter linkage on the D7E. Thanks for clarifying that Mag.

"Old wrote:

There are no decompression push rods. The decompression is achieved by a flat area machined on a round shaft that either interferes with or allows the normal operation of the intake rocker arms which have a protrusion to follow the shaft profile.
If there is a rack limiter for this s/n range I can not find any info in the parts diagram or service manual that shows or describes that function.

I will admit to being in my dreams as I have been a bit full of D8 stuff the last few weeks, anyhow without wanting to drag this poor man through a load of pain trying to start his D9, I will explain the low oil pressure rack limiter on the D9G, the D9H has the peg stop due to the fact it has it's own little oil set up built into the governor control, the D9G's use engine oil pressure that comes via the thin top oil line on the decelerator control forcing the piston down against the shoulder on the lower sleeve, with oil pressure the decelerator acts as a solid to allow normal operation, when you depress the decelerator it rotates the control valve opening the outlet port allowing oil out of the piston area through the lower thick oil line below the feed line, the more the control valve is opened it will reduce the engine speed to low idle, if there is no oil pressure the engine will still start as normal but it will not be possible to accelerate the speed, if there is low oil pressure the speed might be increased some but not to high idle, when a D9G is started it cannot and will not run at high idle until the oil pressure is below the piston, so it's like a peg working on the rack but more fancy, no oil pressure no rev's, the bleeding of the g's I have always done via the hand wheel bleed valve and through the top nuts on the injector lines with the throttle control pushed all the way off and never failed to get a prompt start tctractors

OK, thanks for the explanation, I follow completely. As a function of the Decelerator, lack of oil pressure will allow the engine to be started but cannot be accelerated.
Does not appear to be a problem here as the pumps are supplying ample quantities of fuel.

I feel if the engine was in decompress it would spin on the starter a lot faster than it is ? the amount of fuel the pumps were pushing out was plenty enough to bring about clouds of white smoke bellowing from the stack, it might be worth removing the 7 bolts and side plate of the pump again as it's something simple causing this lack of firing, when an engine stands for a long time the valve seats can fail to do their job but I would still expect the white smoke to be blowing, anyhow it looks to be getting pulled to bits now so I can recommend a Tipex" marker pen and the 3H1690 gauge to simplify things. tctractors

Injection pumps can be tested if you can find a shop with the test apparatus.
Pump part # is a 2S7264 = 8M2701 = 5L2972, 12mm pumps for the 6-1/4" bore engine.
I have the test specifications if required.

Seems like a compression test would be in order, and testing the pump with a nozzle attached to the end of a line.

"tctractors" wrote:

I feel if the engine was in decompress it would spin on the starter a lot faster than it is ? the amount of fuel the pumps were pushing out was plenty enough to bring about clouds of white smoke bellowing from the stack, it might be worth removing the 7 bolts and side plate of the pump again as it's something simple causing this lack of firing, when an engine stands for a long time the valve seats can fail to do their job but I would still expect the white smoke to be blowing, anyhow it looks to be getting pulled to bits now so I can recommend a Tipex" marker pen and the 3H1690 gauge to simplify things. tctractors

After all the comments and even had a shop in (H&H) Washington state look at the video and they stated that is not my problem ie the Injection Pump. They felt as everyone else felt it must be something else... I was not planning on removing anything within the fuel rack assembly or start tearing into anymore... I was going to just put back the Injection pump with new gaskets of course and move on... Replace the starter and cross fingers and check for decompress lever ect... Its frustrating but one way or the other we will sort her out...

I dont want to start messing with the pump as I dont want to screw anything more up... I should have waited until I heard back from everyone regarding pump feedback... Bad enough it is off the tractor...

"Old wrote:

There are no decompression push rods. The decompression is achieved by a flat area machined on a round shaft that either interferes with or allows the normal operation of the intake rocker arms which have a protrusion to follow the shaft profile.
If there is a rack limiter for this s/n range I can not find any info in the parts diagram or service manual that shows or describes that function.

I dont think I ever gave the whole serial number so here it is....


66A08405. (Caterpillar tells me she is a 1970) Is that correct?

And can anybody help me with ordering new gaskets for the Injection Pump. Just the two main ones and any others that need to be replaced why she is out... I feel dumb just putting her back in but I should have never taken her out in the first place...