Minneapolis Model UTU Heads

[tracfac]

Hello, I have a MM UTU that I am having some issues with. I got the tractor from my wife's uncle who restored it originally. This tractor has sentimental value for our family due to the fact that this tractor was purchased used by my wife's father and his cousin while they were in high school in the mid-fifties and after a couple of seasons of custom plowing they were both able to buy brand new 57 Chevy's their Senior year.

The tractor eventually wound up in a pasture for years and I believe it came from the factory as a propane model. During restoration the rear end and transmission were replaced from a parts tractor due to the gear train being wrecked. He also converted the engine to gas, and put a TXS 67 on it. The propane system had been robbed of so many parts and the tank had been left open to the elements.

MINNEAPOLIS MOLINE TRACTOR DATA

MODEL = UTU

TRACTOR SERIAL NUMBER = 324833U

ENGINE MODEL = KEF

ENGINE SERIAL NUMBER = 5?3864F (tag has a marred spot on second number)

Right now in cold weather I am having issues with carburetor icing. I think I need to replace the exhaust manifold to the gas model which will direct heat towards the carb for de icing purposes. I put a Pertronix Ignition on it and rebuilt the carb. The engine has ran fine, just seemed to be low on power even in warm weather. During a Christmas Parade the carb iced up and the engine started missing. Sometimes it would throttle up and try to run, and then it would either slow down and die, or just die. I wrapped a rag around the carb and that seemed to help. But the power was low.

I ran a compression test yesterday with it cold and had high numbers. I saw a thread where someone said the marking for the High Compression Propane head was under the valve cover. I also think there is HC cast on the head. I had one cylinder that was 15 psi lower than the others. Today I am going to reset the carb, let it run till warm, and then run the compression again. If the carb doesn't line out, I will rebuild that again and make sure it is clean. While checking the valves, I will look for the part number which I read somewhere is beneath the valve cover.

Has anyone here had any luck running gasoline with a propane style head? It is my understanding that the valves and seats are different, and if that is so can I rebuild it with the right parts, and run the same one piece head? Or do I need to start looking for gasoline heads due to other physical differences that new parts cannot fix? I am also going to check the head for a part number beneath the cover. I have read somewhere that is where that is located.

Any information will be greatly appreciated and I wish to thank everyone in advance for their ideas and help. Sorry this is so long. Thank you all again.

 

[rustred]

Hello, I have a MM UTU that I am having some issues with. I got the tractor from my wife's uncle who restored it originally. This tractor has sentimental value for our family due to the fact that this tractor was purchased used by my wife's father and his cousin while they were in high school in the mid-fifties and after a couple of seasons of custom plowing they were both able to buy brand new 57 Chevy's their Senior year.

The tractor eventually wound up in a pasture for years and I believe it came from the factory as a propane model. During restoration the rear end and transmission were replaced from a parts tractor due to the gear train being wrecked. He also converted the engine to gas, and put a TXS 67 on it. The propane system had been robbed of so many parts and the tank had been left open to the elements.

MINNEAPOLIS MOLINE TRACTOR DATA

MODEL = UTU

TRACTOR SERIAL NUMBER = 324833U

ENGINE MODEL = KEF

ENGINE SERIAL NUMBER = 5?3864F (tag has a marred spot on second number)

Right now in cold weather I am having issues with carburetor icing. I think I need to replace the exhaust manifold to the gas model which will direct heat towards the carb for de icing purposes. I put a Pertronix Ignition on it and rebuilt the carb. The engine has ran fine, just seemed to be low on power even in warm weather. During a Christmas Parade the carb iced up and the engine started missing. Sometimes it would throttle up and try to run, and then it would either slow down and die, or just die. I wrapped a rag around the carb and that seemed to help. But the power was low.

I ran a compression test yesterday with it cold and had high numbers. I saw a thread where someone said the marking for the High Compression Propane head was under the valve cover. I also think there is HC cast on the head. I had one cylinder that was 15 psi lower than the others. Today I am going to reset the carb, let it run till warm, and then run the compression again. If the carb doesn't line out, I will rebuild that again and make sure it is clean. While checking the valves, I will look for the part number which I read somewhere is beneath the valve cover.

Has anyone here had any luck running gasoline with a propane style head? It is my understanding that the valves and seats are different, and if that is so can I rebuild it with the right parts, and run the same one piece head? Or do I need to start looking for gasoline heads due to other physical differences that new parts cannot fix? I am also going to check the head for a part number beneath the cover. I have read somewhere that is where that is located.

Any information will be greatly appreciated and I wish to thank everyone in advance for their ideas and help. Sorry this is so long. Thank you all again.

you are worrying about something that is totally a normal situation. all carbs ice up in cool weather. nothing can be done to prevent the actual ice up. its called the venturi effect. even in on a hot summer day u can feel the carb outlet and it will be cool to the touch. all you need to do is let it idle till it warms up before putting it to use. putting a heat houser on the tractor will help. cover the rad at the front to keep the engine temp up. even cardboard on the engine sides will help. even if you wrap the manifold intake above carb with that foil insulation would help. post you compression numbers. even warming up the tractor then shutting it off for a while then starting it could help some. i have seen tractors with solid ice on the carb in winter time but it eventually will melt with engine heat but not totally.

 

[molinegb]

Common on a U to frost up.

 

[tracfac]

you are worrying about something that is totally a normal situation. all carbs ice up in cool weather. nothing can be done to prevent the actual ice up. its called the venturi effect. even in on a hot summer day u can feel the carb outlet and it will be cool to the touch. all you need to do is let it idle till it warms up before putting it to use. putting a heat houser on the tractor will help. cover the rad at the front to keep the engine temp up. even cardboard on the engine sides will help. even if you wrap the manifold intake above carb with that foil insulation would help. post you compression numbers. even warming up the tractor then shutting it off for a while then starting it could help some. i have seen tractors with solid ice on the carb in winter time but it eventually will melt with engine heat but not totally.

Thank you for the info. I knew it made a lot of water on the outside in warmer weather. Enough to drip off and make you think your leaking water. I have done more research and found my compression to be very close. I had 120 psi on 1, 2, and 4. Number three has 105. I have noticed oil leaking out from the middle of the manifold port in the 2 and 3 area. None of the plugs has ever fouled. Number two is the cleanest of all. If I can't get more power today, I will removed the top and adjust the valves after I warm it up. fI found another post here that shows compression ratio's for the various heads used with gasoline and propane. I either have the highest rated ratio or the one just below it. If it's the highest ratio, It could be a bit low, if it's the other I think it's pretty close to right. Today I plan on running it again after I remove the carb and make sure it's clean and I don't have any jets fouled. If I can pick up power there, I may be okay. Either way as I dig deeper and start to see more part numbers I will be able to tell better. Thank you so much again!

 

[tracfac]

Common on a U to frost up.

Thank you for the reply and the information. As I stated above it is quite the little water maker in warm weather. I am hoping if anything I can get away with a valve and carb adjustment and pick up power. The neck of the carb is pretty small which adds to the venturi issue. I may also see about larger jets for the carb or buying a new set and drilling out one a bit to test. Thanks again!

 

[tracfac]

Has anybody ever encountered the single head and block assembly not seperating while trying to pull the head off to remove the pistons? I have split the tractor and pulled the engine out and have it up on my bench. It seems that the last time it was taken apart someone must have either used Permatex or Liquid Nail to put the gasket on that is between the cylinder head and block assembly. I tried to pull the head off (single head) using the rocker stud holes to lift. All bolts were out, and the cylinder block tried to come with it. The pistons are still in, due to being not being able to pull the head. The block with the cylinders is one piece as well. I had to pull the engine complete, (head installed, and pan attached). I have now removed the pan, and have the engine sitting up on my bench where I can attempt to pull the head again. Right now I think I should tear the front end down and verify the timing mark before going further. I feel my best option at this point is to pull the head and block together. I will leave the pistons as are, and let them come out of the bottom of the cylinders as the block section lifts. I plan on putting a strap around the head and block once it lifts enough to do so. That way if the block gasket does release, the block won't fall and damage a piston or crankcase surface. Any opinions or ideas would be greatly appreciated! This is a first time issue for me. I thought about pulling the caps on the rods, but fear of a piston rod or bolt damaging the crank keeps me from trying that. Thank you in advance for any help offered!

 

[molinegb]

Done many single block/heas U's. Head usually comes off easy. Head gasket was probably reused as many were. Some sealer added. Setup prone to not sealing. Head and block may warp. Is reason U after 47 went to twin setup. I always take head off first and pop pistons out top with engine in frame.

 

[rustred]

i went through the same deal on my jet star. some idiot used some kind of cement glue . had the engine with a sling pulling up on the blocks while tapping around the bottom with a sharpened sickle knife. it worked pretty good once you get a very small space. i use permatex high tack sealer on my gaskets all my life and never run into this stupidness. you are going to have to pull the head should have left it in the tractor and tryed it the way i did.

 

[tracfac]

Done many single block/heas U's. Head usually comes off easy. Head gasket was probably reused as many were. Some sealer added. Setup prone to not sealing. Head and block may warp. Is reason U after 47 went to twin setup. I always take head off first and pop pistons out top with engine in frame.

I think your right about the gasket. My main issue was it will split at the crank case and block, but not the head and block. Never got a gap there. So I will give the bench a try and pull it in one piece then seperate it later. I will come up slow, and see what happens.

 

[tracfac]

i went through the same deal on my jet star. some idiot used some kind of cement glue . had the engine with a sling pulling up on the blocks while tapping around the bottom with a sharpened sickle knife. it worked pretty good once you get a very small space. i use permatex high tack sealer on my gaskets all my life and never run into this stupidness. you are going to have to pull the head should have left it in the tractor and tryed it the way i did.

Yes and most folks if a little is good a lot is so much better! I think I will hang it on the hoist and lift it up. I will tap around it with something sharp, ( I too am not a fan and see if it will release. ) If so then can flip it and pull the piston's that way. Thank Goodness my bench is a full sheet of half inch plate. I have a brass wedge that I can sharpen and see if that works. Thanks for your input! I have to be honest too, I was sort of hoping that wrestling it around might have knocked it loose. It didn't. Right now I think my worse case scenario is pulling it in place and it doesn't seperate. Thanks again!

 

[Dennis P]

Hello, I have a MM UTU that I am having some issues with. I got the tractor from my wife's uncle who restored it originally. This tractor has sentimental value for our family due to the fact that this tractor was purchased used by my wife's father and his cousin while they were in high school in the mid-fifties and after a couple of seasons of custom plowing they were both able to buy brand new 57 Chevy's their Senior year.

The tractor eventually wound up in a pasture for years and I believe it came from the factory as a propane model. During restoration the rear end and transmission were replaced from a parts tractor due to the gear train being wrecked. He also converted the engine to gas, and put a TXS 67 on it. The propane system had been robbed of so many parts and the tank had been left open to the elements.

MINNEAPOLIS MOLINE TRACTOR DATA

MODEL = UTU

TRACTOR SERIAL NUMBER = 324833U

ENGINE MODEL = KEF

ENGINE SERIAL NUMBER = 5?3864F (tag has a marred spot on second number)

Right now in cold weather I am having issues with carburetor icing. I think I need to replace the exhaust manifold to the gas model which will direct heat towards the carb for de icing purposes. I put a Pertronix Ignition on it and rebuilt the carb. The engine has ran fine, just seemed to be low on power even in warm weather. During a Christmas Parade the carb iced up and the engine started missing. Sometimes it would throttle up and try to run, and then it would either slow down and die, or just die. I wrapped a rag around the carb and that seemed to help. But the power was low.

I ran a compression test yesterday with it cold and had high numbers. I saw a thread where someone said the marking for the High Compression Propane head was under the valve cover. I also think there is HC cast on the head. I had one cylinder that was 15 psi lower than the others. Today I am going to reset the carb, let it run till warm, and then run the compression again. If the carb doesn't line out, I will rebuild that again and make sure it is clean. While checking the valves, I will look for the part number which I read somewhere is beneath the valve cover.

Has anyone here had any luck running gasoline with a propane style head? It is my understanding that the valves and seats are different, and if that is so can I rebuild it with the right parts, and run the same one piece head? Or do I need to start looking for gasoline heads due to other physical differences that new parts cannot fix? I am also going to check the head for a part number beneath the cover. I have read somewhere that is where that is located.

Any information will be greatly appreciated and I wish to thank everyone in advance for their ideas and help. Sorry this is so long. Thank you all again.

Almost sounds like a governor problem for low power, it isn’t opening up all the way. I had a UT with a similar issue and I had to bend rod between governor and carb to correct wear problem. The propane heads are higher compression which should help give a little more power. The icing issue and killing the motor is interesting, shouldn’t do that.

 

[Dennis P]

Hello, I have a MM UTU that I am having some issues with. I got the tractor from my wife's uncle who restored it originally. This tractor has sentimental value for our family due to the fact that this tractor was purchased used by my wife's father and his cousin while they were in high school in the mid-fifties and after a couple of seasons of custom plowing they were both able to buy brand new 57 Chevy's their Senior year.

The tractor eventually wound up in a pasture for years and I believe it came from the factory as a propane model. During restoration the rear end and transmission were replaced from a parts tractor due to the gear train being wrecked. He also converted the engine to gas, and put a TXS 67 on it. The propane system had been robbed of so many parts and the tank had been left open to the elements.

MINNEAPOLIS MOLINE TRACTOR DATA

MODEL = UTU

TRACTOR SERIAL NUMBER = 324833U

ENGINE MODEL = KEF

ENGINE SERIAL NUMBER = 5?3864F (tag has a marred spot on second number)

Right now in cold weather I am having issues with carburetor icing. I think I need to replace the exhaust manifold to the gas model which will direct heat towards the carb for de icing purposes. I put a Pertronix Ignition on it and rebuilt the carb. The engine has ran fine, just seemed to be low on power even in warm weather. During a Christmas Parade the carb iced up and the engine started missing. Sometimes it would throttle up and try to run, and then it would either slow down and die, or just die. I wrapped a rag around the carb and that seemed to help. But the power was low.

I ran a compression test yesterday with it cold and had high numbers. I saw a thread where someone said the marking for the High Compression Propane head was under the valve cover. I also think there is HC cast on the head. I had one cylinder that was 15 psi lower than the others. Today I am going to reset the carb, let it run till warm, and then run the compression again. If the carb doesn't line out, I will rebuild that again and make sure it is clean. While checking the valves, I will look for the part number which I read somewhere is beneath the valve cover.

Has anyone here had any luck running gasoline with a propane style head? It is my understanding that the valves and seats are different, and if that is so can I rebuild it with the right parts, and run the same one piece head? Or do I need to start looking for gasoline heads due to other physical differences that new parts cannot fix? I am also going to check the head for a part number beneath the cover. I have read somewhere that is where that is located.

Any information will be greatly appreciated and I wish to thank everyone in advance for their ideas and help. Sorry this is so long. Thank you all again.

The head might need rebuilt, but it’s the correct one. (I didn't finish the first post because I hit the wrong button!) sounds like one cylinder might have a leaky valve. New valves are not a problem to get and work between straight and split blocks. I have MM engines with propane intakes and factory carb and have no problem with icing affecting the way it runs. Make sure you have a t-stat with a 1/8 inch hole in so engine comes up to temp. With these old carbs, someone could have installed the incorrect Venturi in it. Someone posted the carb venturi sizes on this site somewhere.

 

[tracfac]

Well I have figured out the problem with the U engine. I pulled the head and block assembly as one. The head gasket was stuck solid to the block and head. The machine shop vatted it and was able to get it apart. The head is shot. Visible cracks between the valve seats in 3 of the cylinders which were verified with Magna flux. The one that isn't visible probably is too just from how it looks. Right now I have located another engine that I will pick up on Wednesday. It too has the solid head and block. This is a total gamble. If that doesn't pan out then I will seek to find two cylinder heads and blocks to replace the singles with. The head showed signs of pitting on three of the cylinders. Since it didn't have a thermostat in it the engine never overheated. I think it was putting steam/water into the cylinders while running and was starting to kill the spark. I also think the guides were shot as well. So the quest goes on. Have a feeling that the search for heads and blocks may be tough. Thanks all for your reply's and ideas! I may have found a rebuilt head that is a single and available for purchase. However I fear that my block is going to have be bored and sleeved. Does anyone know if you can bore and sleeve back to standard size? I don't think pistons are available for this. If so, I can bore the block, sleeve it and run my pistons. They still look fine. Any ideas are greatly APPRECIATED IN ADVANCE!

 

[molinegb]

Well I have figured out the problem with the U engine. I pulled the head and block assembly as one. The head gasket was stuck solid to the block and head. The machine shop vatted it and was able to get it apart. The head is shot. Visible cracks between the valve seats in 3 of the cylinders which were verified with Magna flux. The one that isn't visible probably is too just from how it looks. Right now I have located another engine that I will pick up on Wednesday. It too has the solid head and block. This is a total gamble. If that doesn't pan out then I will seek to find two cylinder heads and blocks to replace the singles with. The head showed signs of pitting on three of the cylinders. Since it didn't have a thermostat in it the engine never overheated. I think it was putting steam/water into the cylinders while running and was starting to kill the spark. I also think the guides were shot as well. So the quest goes on. Have a feeling that the search for heads and blocks may be tough.-47 Thanks all for your reply's and ideas! I may have found a rebuilt head that is a single and available for purchase. However I fear that my block is going to have be bored and sleeved. Does anyone know if you can bore and sleeve back to standard size? I don't think pistons are available for this. If so, I can bore the block, sleeve it and run my pistons. They still look fine. Any ideas are greatly APPRECIATED IN ADVANCE!

Common for single head to crack. Have several.same condition. Have 3 NOS pistons. Block used from 38-47 as well as head. Actually goes back to KT and KTA 1930-38 Only change was the HC head for gas. Many of the blocks cracked also.

 

[Dennis P]

Well I have figured out the problem with the U engine. I pulled the head and block assembly as one. The head gasket was stuck solid to the block and head. The machine shop vatted it and was able to get it apart. The head is shot. Visible cracks between the valve seats in 3 of the cylinders which were verified with Magna flux. The one that isn't visible probably is too just from how it looks. Right now I have located another engine that I will pick up on Wednesday. It too has the solid head and block. This is a total gamble. If that doesn't pan out then I will seek to find two cylinder heads and blocks to replace the singles with. The head showed signs of pitting on three of the cylinders. Since it didn't have a thermostat in it the engine never overheated. I think it was putting steam/water into the cylinders while running and was starting to kill the spark. I also think the guides were shot as well. So the quest goes on. Have a feeling that the search for heads and blocks may be tough. Thanks all for your reply's and ideas! I may have found a rebuilt head that is a single and available for purchase. However I fear that my block is going to have be bored and sleeved. Does anyone know if you can bore and sleeve back to standard size? I don't think pistons are available for this. If so, I can bore the block, sleeve it and run my pistons. They still look fine. Any ideas are greatly APPRECIATED IN ADVANCE!

Yes, you can sleeve the cylinders and then bore to the size you want. Bore it, but leave a 1/8 to 1/4 inch lip at the bottom for the sleeve to sit against. Then cut the excess off the top. Also, check the ring clearance in the piston while you’re at it. I had to open up the top land and put a thicker ring in it. Otto Gas Engine can get about any ring you want. Melling makes the sleeves.

 

[tracfac]

Yes, you can sleeve the cylinders and then bore to the size you want. Bore it, but leave a 1/8 to 1/4 inch lip at the bottom for the sleeve to sit against. Then cut the excess off the top. Also, check the ring clearance in the piston while you’re at it. I had to open up the top land and put a thicker ring in it. Otto Gas Engine can get about any ring you want. Melling makes the sleeves.

Thanks for the info. I will add these to my list of vendors. I have seen where standard size rings are available. Different pistons seem to be rare to find! I was really suprised how good the rings and pistons looked in the engine when I tore it down considering how bad it was running.

 

[ksmms]

Where’s your location? I have 2 straight block heads I’d sell. Few other parts also. I’m in northern Illinois

 

[tracfac]

I live in southern Oklahoma. I have located some parts in Kansas that I will get in two days. However I may be interested in what you have. Thanks for reaching out and I will let you know!