Super MDTA

[molinegb]

Recently got asked to get a Super MDTA running again. Was restored but been sitting inside for a few years. Never worked on one that starts on gas and switches over. Any thing specific to look for? Is going to be for sale.

 

[rustred]

Nothing much different than the ordinary gas engines. If you get them running from sitting then you know what to do. Other than the injection pump rack might be stuck. Then it won’t switch over to diesel. Might want to drain and refill the injection pump with new oil , as on most of them the transfer pump seals leak and fills the pump with diesel. It hold so about a pint of engine oil. Drain is under the oil level pet cock.

 

[Janicholson]

Recently got asked to get a Super MDTA running again. Was restored but been sitting inside for a few years. Never worked on one that starts on gas and switches over. Any thing specific to look for? Is going to be for sale.

Ill ad to Rust Red's good ideas that it probably has a distributor coil system that turns CCW instead of the normal IH CW. the gap is still .020. If it has a Mag, the mag also turns CCW. In the gas start position of the change over lever, it will crank easily with the starter. in the diesel run position it will not crank (or just barely) even with a hot battery. The spark is shut off in diesel run mode, so there will be no coil voltage. Stopping is done with the speed control lever. put it about 1/2 way to start it. Run it on gasoline for 4 to 6 minutes on this first start, then switch. When switched there should be white smoke (unburned diesel) to begin with as the cylinders react to getting squirted. ( have owned a MD and started it after 10 years of a farmers neglect. The rack was stuck, No smoke) and I took the cover off the injection pump and used PB Blaster and carb cleaner to un gum the system. There are videos. All MDs are 12 v positive ground if stock. if they have been converted to an alternator they are likely negative ground. Pay attention the the battery terminal size/connection if jumping, charging, or replacing the battery. Keep us in the loop and we can help. Jim

 

[molinegb]

Quite familiar with inline pumps. Done lots of gas and diesels but not as one. Haven't seen it for a few years but sure is latest one with distributor. Guess just diagnose as a gasser and then a diesel.

 

[caterpillar guy]

Our MD was negative ground since we have had it for about 50 year or so now. Got changed over later to the alternator. I suppose somebody could have switched it before we got it.

 

[JOCCO]

A lot! get the manual. A lot of things have to come together at the correct time. All the parts on the gas side are different. Diesel side is not like a modern pump.

 

[molinegb]

A lot! get the manual. A lot of things have to come together at the correct time. All the parts on the gas side are different. Diesel side is not like a modern pump.

Not buying manual as not my tractor and was restored like 8 years ago..

 

[rustred]

Not buying manual as not my tractor and was restored like 8 years ago..

and it was stored inside, and an experienced guy dont need a manual to start a tractor. lol

 

[DanMD]

There is a good chance it may have a stuck starting valve if it's been sitting unstarted.

 

[caterpillar guy]

The change over valves may be stuck in the closed postion and if so they will probably open when pushed with the change over lever to the gas position then will not close thus making it miss when run on the diesel side.Our MD was like that when we got it. We ran it hard on the manure spreader back then for a few days hauling manure in snow and it finally went to hitting some of the time. They had needed to be moved on a regular basis to keep them freed up. Parts are expensive and hard to find for some of them. They are heavy in the front end so not a good tractor in the mud.

 

[rustred]

The change over valves may be stuck in the closed postion and if so they will probably open when pushed with the change over lever to the gas position then will not close thus making it miss when run on the diesel side.Our MD was like that when we got it. We ran it hard on the manure spreader back then for a few days hauling manure in snow and it finally went to hitting some of the time. They had needed to be moved on a regular basis to keep them freed up. Parts are expensive and hard to find for some of them. They are heavy in the front end so not a good tractor in the mud.

and if they are stuck closed then you will break the changeover lever inside the valve cover when pushing on the buttons to open them. this tractor is sitting inside , so all the hypothetical ideas are coming out.

 

[caterpillar guy]

Ours always would move to the open position and then not close so would miss on diesel with the ones that didn't close. The button you refer to is setting with oil around it while runnig and is lubricated even when not running .I'm not so sure about the valves and stems on the chanhge over vales them selves so the reason I believe they stick after opening to start on gas. Then with just the spring to close them apparently they don't have the ability to close them if not pretty free moving and setting they are under that cap/button so less lubrication on them.Thats my thought.

 

[Fritz Maurer]

and it was stored inside, and an experienced guy dont need a manual to start a tractor. lol

I didn't get the feeling he is experienced with this motor.

 

[JOCCO]

I didn't get the feeling he is experienced with this motor.

I didn't get the feeling any of them were experienced on it!

 

[molinegb]

I didn't get the feeling he is experienced with this motor.

I didn't get the feeling any of them were experienced on it!

Been repairing/rebuilding motors for over 50 years. Rebuilt a Detroit and most all Moline made. The old guys used to take care of the odd makes. Now all of a sudden there is no "old guys" and I have become the "go to guy." B-275 next. Just got a a TD5 running.

 

[rustred]

Been repairing/rebuilding motors for over 50 years. Rebuilt a Detroit and most all Moline made. The old guys used to take are of the odd makes. Now all of a sudden there is no "old guys" and I have become the "go to guy." B-275 next. Just got a a TD5 running.

U tell them!
I knew that, ha ha.

 

[rustred]

U tell them!
I knew that, ha ha.

And I can say I have been working on these. Gas starts for about that long also. So the joke is not on us!!