Jetstar 3 Engine Parts

Just picked up a 68 JetStar3 with a spun rod bearing. I am looking for a crank and possibly 2 rods for this engine. What other tractor models was this engine used in that I can get the parts from? Did the 445 use the same engine?

Thanks,
Ryan

You would want to stay with newer crankshaft in mid 60's. 445, early Jetstar used the wick
type seal and not the one piece so crankshaft has to be sleeved. Be prepared to change
governor as usually that is where problem originates. Sometimes it will break cam or skirt
in block id #2 rod breaks. Seems to be quite common in last couple of weeks.

Thanks, will keep that in mind. Was wondering about the Governor as I have heard they seem to be the weak link in these tractors. Is there a schematic somewhere online that shows how the Governor is configured in the engine? I have not gotten my manuals yet, and have not gotten that far into the engine.

When you say break cam or skirt, are you referring to on the governor?

Thanks,
Ryan

Have seen con rod break and smash camshaft and block along with side cover. Governor is set
with linkage adjustments. I would change it while it is apart.

If it just spun the rod bearing, and the rod is intact, I would get a machine shop to re-size the connecting rod and grind the crank under size and put under size bearings back in it. That way you will know everything in the bottom end fits like it should.

Having said that, some automotive machine shops can't shave the parting line on MM rods, so you may have to take them to an industrialttype machine shop to do that part of the job, then take them back to the automotive machine shop to hone/ream the bore to spec.

If it spun a rod, probably all the rod big ends are oval now, and you will probably have to get them re-sized anyway.

I may have some engine parts. Rods for sure. I do not remember which style of crankshafts I have. If you are interested my email is [email protected]

Thanks for the info so far. Here is a bit more to the story. The tractor belonged to the guy I bought it from's brother. He had owned the tractor for more than 10 years and used it around his place. Appeared to take good care of it. He was hard of hearing and one day his neighbor was over and commented it sounded like it had a rod knocking. Fortunately they shut it down right then. They took the side cover off and a rod cap off and that is when they discovered the spun bearing. The rod's are in tact so it does not appear there is any other internal damage to the engine.

The one rod cap that is off looks a little beat up, but not sure how bad yet. The crank looks pretty nasty so I do not know if it will clean up with a turning. I am just thinking the worst and looking for potential replacement parts if needed.

Did a little more tear down tonight, did find evidence of moisture in the oil. Could be from condensation but not sure yet. Did not find any oil in the coolant though. Are these engine's known for any head gasket issues? Have not gotten it torn down that far to look at the gaskets.

Have worked on many other engines but this is the first MM I have had apart. Definitely a different beast. The twin cylinder jugs and the water pump setup is unique to say the least

Any additional input you have would be greatly appreciated.

Thanks again,
Ryan

Well, if you are taking it down, both heads have to come off together, there is a water tube between them. And the blocks have to come off together as well for the same reason. left side Block bolts in holes above the camshaft.

The crank has to come out the back of the crankcase, so you will have to split the engine. You sometimes have to either remove a flywheel dowel from the crank or grind clearance in the rear main bearing carrier in order to get it off the crank.

On the subject of governors, are these rebuild-able or just have to be replaced? And where do you suggest getting the parts to rebuild or replace? I have been looking over parts websites and not seeing anything related to the governors except the spring and rod that is on the end of the throttle.

Thanks,
Ryan

Hi Ryan, call us @ 920 295 3278, we should have everything you may need for this project, Dale, riverdalefarmshop.com.

(quoted from post at 17:26:54 10/12/16) Hi Ryan, call us @ 920 295 3278, we should have everything you may need for this project, Dale, riverdalefarmshop.com.

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Thanks Dale, once I know what exactly I need I will give you a shout.

Engine is out and on an engine stand, will start tearing into it soon. I noticed tonight that there was a little antifreeze dripping from cylinder 4's lifters. No sure what is going on there. Hopefully only a head gasket.....

-Ryan

I would watch that RDF one I know someone that had issues with those "experts"