but how would it get into the pony from the main engine unless its through a crack in the block or a blown head gasket? Is there someplace else I need to check in other words? It was at least 2 quarts of coolant.

BrianCamling wrote:

Long time since my last post. Life keeps getting in the way of working on my project. I pulled the pony motor head this summer (thats no easy thing when its still on the side of the big engine). took it and had it magna fluxed and there were no cracks. I bought a spray kit to check for cracks on the top of the block and that checked out clean. I also checked behind the valve lash cover and it was completely clean in that area with no signs of coolant.

I drained the oil and it turned out to be mostly coolant. The head gasket was pretty grimy so I got a new head gasket and have it installed. Before I finish installing all of the other parts though, would a blown head gasket allow for so much coolant to go into the oil pan? I hope so because I am not certain where else it would come from and I would be left with pulling the pony motor completely.

Oh, you bet  a bad head gasket can cause all this!  There were much easier ways to source your issues but I guess you have progress.  You mentioned tightening bolts on the pony.  If any of the head bolts were loose, that is more evidence for a gasket failure.  What is also possible is straight gas got in the engine and blew the head gasket as liquid will not compress.  It is notorious for bending rods but maybe Cat was smart and planned for this.  

If your pony has to run on half choke, you don't need to go any further because that is not normal and a sure sign your pony is running lean, which will be down on power.  I don't recall what kind of jets are in there but as someone that has fixed hundreds of carbs, people make the mistake of only blowing air through a jet to clean it.  That is rarely enough for a badly fouled carb.  I keep small 1/8" steel cable around and I peel off a strand of that to use as a jet cleaner.  The twisties of the wire help get the funk out.  If you look through a jet and can only see a faint hint of light through it, feed a little wire in there (carefully!!!) and then see what you got.  You may also want to check the entire float needle/seat inlet area for debris.  

Also make very sure your fuel tank is breathing!  If a breather hole is partially plugged, you will really chase your tail.  

Your engine wants more fuel, do nothing else until you get it more fuel.  For reference, on my 7, I fired the pony with a touch of choke and turn choke off right after starting.  Let it idle about 30sec, then give it full throttle, then I hit it with the main engine in high gear and full compression!  This is for reasonable weather, but even in the cold, I would just use compression release for a little bit.  Just saying, your pony is not pulling right!  

Starting Engine -
2 Quarts of coolant in the Starting Engine Crankcase? That eliminates the oil for lubrication - Asking for major problems running a starting engine that way at all.
Water intrusion - Gaskets, cracks in block of starting engine - so many locations, water jackets are thin in many places.

Long term running of starting engines is a source of problems, remember they rely upon the main engine water pump to keep them cool, that low rpm at the water pump does little for circulation. Especially when the primary circuit is for the Diesel. Any blockage in the small ports to the starting engine just increases the heat and heat can cause cracks!

Lean Mixture in the starting engine will further cause potential problems - that needs to be resolved.

Under very cold conditions, Low might be necessary on the two speed transmission, in warmer climates - even into the 20-30F range, it was seldom used or needed.
High with no compression, get oil pressure up in main engine, return compression release to full compression side, run for a short while, throw the fuel to the engine. It should fire, at least give you good indication if it is warm. If not responding, shut the fuel off and try again.

There is nothing wrong with adding a light and quick shot of "starting fluid", it sure saves the starting engine and does not harm the main engine. Key is light shot immediately before throwing the fuel to the engine. Some say an Engine becomes ADDICTED - NO SUCH THING - Addiction is purely something living organisms develop.
Too much starting fluid will tend to wash lubrication from the cylinders and cause pre-ignition problems. Easy does it, just a light quick shot at the air intake!
Worn out engines in many cases will not start easily without that 'boost'. Once running, the rpms are increased and thereby, compression loss is not as critical.
Remember - Diesel relies on heat of compression to ignite the extremely fine droplets from the injector.

Family owned a 9G D7 that always "made" water in the starting engine. It had drain cocks on bottom of crankcase, always drained those before doing anything and then ensuring oil level was full on the starting engine. The tractor had seen some severe freeze damage, fortunately main engine only lost the lower radiator tank, but the starting engine had cracks behind the valve springs - as it heated and main engine ran, they leaked. Surprising how much water can enter a crankcase through cracks!

cts

bobby1 and ctsnowfighter, thank you both for your responses. the carb was rebuilt a few years ago by a reliable service that specializes in old carbs, but it could have built up gunk since then. I will go through it to make sure the jets are clean. The one thing I had not thought about was the gas cap. Pretty sure the breather hole is at least partially plugged if not entirely. I think I will go ahead and reinstall the remaining pieces and look at the fuel issues along with the new head gasket to hopefully get it started again. I will report back here on whatever the results are.

save me reading the whole post , try it with air cleaner pipe off