I have a basket case D333C I am putting back in running condition. One of the problems is that the starter (50MT) seems to be butting gear teeth with the flywheel and not engaging the starter motor. About 1/4 times it will only hit with a mighty clunk but not send voltage to the starter. Replaced the solenoid already, no change. The starter appears to have been replaced with used by somebody else at some point. If I roll the engine by hand a tiny bit it will crank right up, but if it is in the butted condition it will do nothing. I would post pictures but I can't find the pictures I took.
just a thought ring gear on flywheel isn't on backwards is it
In this day and age if you are not using a 39MT you are living in the ancient past.
I've often heard that but never had any occasion to do anything about it. Is there just one 39MT to install or are there specific configurations to match the bell housing/ring gear? This is a military generator from 1972 so likely little information on what they used especially in Cat part number lingo, the govt had their own part numbers and hard to cross. I don't see that it has been apart but I guess I might be able to tell by removing the starter which is a royal pain according to my employee who worked on these things when they were still in normal service.
Does it have a Cat Serial Number on it by any chance.? I would suspect it might be 62Mxxxx. There are cross references available from MIL products to civilian.
Sorry I thought I had posted the serial number. It is 62M424
No worries. Use commercial Serial Number 66D5140 for all parts and service information.
8200308 is a clock-able starter, providing it's eleven tooth.
I haven't had the starter off yet, but it looks like from the PN on the starter that the catalog says it should be an 11 tooth 50MT, SAE3, 5/8 holes. Does the starter arrangement go with the engine serial number or is the bellhousing and such part of the equipment? 8200330 looks like maybe the 24 volt equivalent of the 8200308. I'm also looking for the gasket that holds the fuel pressure regulator to the injection pump, the Cat shop has not gotten back to me yet, I will give them 66D05140 and see if that helps them any. The owners had put silicone for a gasket in there and once I got their messed up fuel piping back the way it should be and finally got it to run under its own power it quickly blew like Vesuvius and shot fuel everywhere so we are dead in the water until we can get that fixed and see if the engine runs correctly and is worth investigating the starter issue further. Another guy on this site said he never takes on somebody else's project, well if I never did that I would not have any work. Good times.
There is one 39MT and a few variants like 12V or 24V, 11 or 12 tooth (I thought your engine should be 12 teeth as it is essentially a 3306.) rotation direction etc.
First issue--is what's a 50MT doing on a engine that small? Basket case is, as basket case does.
I don't know, the rest of the engine is military green and this starter is yellow but not Cat yellow - looks like the lighter faded yellow color that imitation construction equipment of the era tended to have. If you had seen their yard you would understand, lots of equipment from the 80s sitting on the dead line and not so dead line, they still use it.
Unfortunately there is no detailed information. Remember we are crossing a MIL Serial Number to a "typical" commercial one. For 66D05140 I see maybe a dozen starter motor options (although some are air starters) and no way of telling which exact one should be on your particular engine. Question: 12v or 24v electrics.? The answer to that might narrow the field down a little.
24 volts
The starter that is on there now is number 1109979
For a 24V system there is apparently only one option for the entire Starter Motor Group - 8L-4048. Depending on age there are two options of starter motor within that 8L-4048 - the 2S-0900 shown below, or 4N-3347 that I will put in a separate post.
The 4N-3347 starter motor
That 2S-0900 looks to be a 24V 40MT, which is more inline with a engine that size.
According to my searches the most common cross for Cat 2S-0900 is a Prestolite M1057416E. https://www.prestolite-eu.com/Category/M1057416E
2S-0900 or 4N-3347 both cross into the same aftermarket part number for a 40MT. 12 tooth not 11 tooth like the one that is on there. Confirmed the ring gear is on correct, looks to be in very good condition. Looks like 8200435 might be my part number, shows both as an upgrade to the 40MTs shown above, and also from this chart, https://www.delcoremy.com/getmedia/3bace459-9b09-43d3-bcd4-19df77450850/Delco-39MT-Sheet-6-20.pdf.aspx and if you click on some of the applications it does not list a D330C but it lists a lot of tractors that have a 3306 in them which is mostly the same I believe. There was one chart that seemed to show a different gear tooth pitch but I can't find it any more, info is sketchy.
Maybe someone has just grabbed some old Delco starter motor and whacked it on there, with the wrong number of teeth. It was a pretty standard size so many different variant delco style starter motors will all bolt on there. Does not engage properly, makes clunking noises. I would be checking tooth sizes. The old D6C's with the D333C engine had a 12 tooth 8S9540 starter motor fitted. But maybe the military wanted a standard sized starter motor on everything for logistical simplicity so caterpillar obliged and made these military ones special with a different starter, just for them.