210 engine rebuild vid

I use 3m silicone paste for sleeve orings. Was thought that in tech school and have rebuilt a lot of engines that way with zero issues.

I was still trying to get enough money for an overhaul for this 220 I have. All overhaul kits need to be honed to get enough piston clearance for a non piston cooling engine?

When I started on wet sleeves AC had a paste in a tube...At an AC service school was told

Edited by orangereborn - 24 Feb 2023 at 12:07am

For those who haven't worked on a 426, they have 3 Orings, not the typical 2.

I'm sure Reliance is using the updated second piston ring that A-C started using in 1978 or 79.  They say "lightly" applied sleeve Oring lube, which is what I have been preaching, LIGHTLY. Because excessive or heavier viscosity lube squeeze the sleeve and/or damages the Orings when assembling. I also contend that if they (and others) are using that .0025" to .005" skirt clearance dimension spec, that is too tight and is absitively too tight for non-piston cooled engines, as the piston swells up more under load and that .0025" clearance goes to ZERO and that's when the crap hits the fan.

uploads/8665/15140ACD-4C20-41BC-BDA6-381384671C0D.jpeg.

Edited by Mikez - 24 Feb 2023 at 10:20am

looks like it ate a bunch of dirt.

I would like to know how much experience they have with the non piston cooled 426 or any AC diesel for that matter they said in the video they have 40 years experience and also say in the same video they rarely get to do the full assembly of the engine so can't have it both ways.The wise have spoken from experience it's their choice to heed it or hold their own. But on the bright side there's a 50/50 chance we can get a second why did it fail video for entertainment purposes. But what do I know I'm just a dumb farmer

First off, it is very unfortunate that they have had a such a catastrophic failure in such a short time of operation on new parts. Like so often on this website, all the information isn't readily given, so coming up with an accurate cause or solution is more difficult. I would have assumed the injection pump was timed properly to the #1 cylinder. Their methodology was correct...align the crank pulley to 24 degrees BTDC and the mark inside the pump should line up. They even made sure the crank pulley was indexed reasonably correct and it indeed was. But it was never mentioned that they HAD to time it on #6 instead of #1. Like Ed just said, I don't think it could have actually been "timed" correctly because of the way the governor weight retainer is splined/attached to the pumps rotor. It isn't just #1 or #6. It can fit differently than that, so 24 degrees BTDC may have actually been 32 degrees BTDC. I could see in this last video the injector spray pattern much better than the previous video, and yet while it wasn't over the top of the bowl, it wasn't down in the bowl 100% either. I agree with them 100%, this was not a cooling system issue. Those engines don't "air lock" if you take your time filling the radiator, and I'm always cognizant of how many gallons I have poured into an empty cooling system. There is a proper cooling system capacity for every machine. The piston skirt clearance was checked on a good sleeve and piston and found to be within the .0025" and .005" range, which is within specs. I've found that within the range given, the nominal figure is usually near the center of the specs, which it was. This I can assure you: when that sleeve is installed in the block with the Orings, it certainly won't be any looser on skirt clearance. I was very surprised to recently find that according to my official A-C service manuals that a D-21 engines skirt clearance was .0065" to .009", while the 210/220 engines (and newer) are listed to be .0025" to .005".  How could this possibly be ?? The engines are identical in almost every way. Could there be a mistake in information transferred from the printing of one manual to a newer manual ??  I don't have any service bulletins from that mid 1960's to early 70's time frame to know if there was a legitimate tightening of these numbers or not, I was still in high school !! This I know from all my years of working on these engines, non piston cooled 426 engines are more prone to skirt scoring than any of the piston cooled engines.  And why wouldn't they be ?? If the pistons aren't bathed with oil from underneath to help keep them cool, they swell up more under 100% full load and the hotter the day, the cooling system runs warmer than on a Fall day, which can contribute to even hotter pistons, making the skirt clearances even tighter !!  I'm just saying looser is better on these older engines because of what I have seen over the years. We even had a 7030 one day on the dyno (an engine with 4 or 5,000 hrs on it) under full load lock up and stall from a scored piston !!  So it does happen and makes you want to puke when it does !!  So, ever since that incident and other stories I have heard from fellow dealers, .007" minimum skirt clearance has been my preferred spec to never have an issue, just like the D-21 engine. There were two types of piston cooling on these 426 engines. The early design was a small hole drilled in the upper main bearing saddle that was aimed at the underside of the piston just missing the connecting rods piston pin end. The second design was when they went to a 3-ring piston with the larger piston pin and pumped the oil thru a rifile drilled connecting rod to the pin bushing and then the cooling nozzle on top of the rod. Either way, piston temps were reduced by being constantly cooled with engine oil. I'm sure they'll get it back together and with things being timed correctly, it will be fine.

Edited by DrAllis - 26 Feb 2023 at 4:13pm

They've been made aware of that and the turning around the conn rods with slotted rod bearings.

Edited by DrAllis - 26 Feb 2023 at 4:25pm

The pump timing itself wasn't 180 off. The actual pump timing must have been 10 degrees advanced and that is just a guess, but it was advanced, not retarded. The timing mark inside the pump was 180 off, or not really but it was 170 or 190 degrees off. Like Ed said, the splines on the timing mark part aren't exactly 180 off. So, anyway, they timed it on cylinder number 6, which if it was exactly 180 off, would have been fine. If it was a pump off of a 180 thru 200 tractor, it is exactly 180 degrees different because the timing mark inside the pump only assemble two ways...correct or 180 off. The D21/210/220 can assemble 23 different ways, I think. Anyway it is splined so many choices.

So, we don't actually know how the wrong timing mark positioning in the injection pump was discovered, do we ?? Did Jim's notice with the injection pumps marks aligned in the window it didn't have the rotor discharge hole showing at the #1 port ?? or did the whole injection system get completely installed and then the engine wouldn't start ??  At some point Jim's had to figure out the pumps lines were approx 180 degrees off. Maybe they made a phone call to their pump rebuilder and were told " well, just time it on #6 and it will be fine" ?? which of course would have been OK (on a DB pump) or maybe not OK (on a DC pump) ?? which if that was the case, that would have been poor advice to Jim's.

Diesel timing lights just verify the advance is working. I trust them for nothing else.

DrAllis wrote: Diesel timing lights just verify the advance is working. I trust them for nothing else.

Yes the service manual said the orange oring was a silicone type and the black were buna n I believe.