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Trying to get a 48 started

Mon Jan 07, 2013 4:31 pm

I bought this tractor as a parts machine since so much of it is missing. Well in the past few months I have some gathered the parts needed to complete the tractor. All but a generator.

Anyway, I pulled the tractor in to pull parts off of it and that didn't happen, now I am trying to get it running, why, I don't know. So I got things wired up, had to wire the coil straight to the battery since wiring in such bad shape and I started to crank it over and got a cough every now and then. I did a complete tune up as the distributor is the one for my demo and I rebuilt it. New coil and I thought it would start. Well not exactly, two stuck valves to free, so I got them loose and still no luck. I didn't have my compression tester so I used my thumb over the holes and wow, #1 is strong, #2 nothing, #3 and #4 were good but nothing like #1. So I sprayed the cylinders full of PB Blaster last night and again this morning and at noon hour. I was thinking of pulling to start tonight if compression levels are good. I did pop the head and found all valves to look good so that makes me think the #2 cylinder has some gummed up stuck rings.

Let you all know how things turn out but it has been fun working with it. I think if it runs and runs good I may fix her up with the demo.

Re: Trying to get a 48 started

Mon Jan 07, 2013 4:59 pm

Seems to be what happens to me also. Buy something with the intent to part it out or fix it up and sell it for a profit. Well so far 8 out of 10 have stuck around. Lol. Why junk something with potential right? :mrgreen:

Re: Trying to get a 48 started

Mon Jan 07, 2013 9:40 pm

Hey you can get a cub running on a couple of cylinders and the fix it from there. You need fuel and fire at the right time. After that it gets choosy.

Re: Trying to get a 48 started

Mon Jan 07, 2013 10:04 pm

So tonight I took off the head to see why I have no compression in #2 cylinder. Well with compression tests at #1 70, #2 0, #3 55, #4 40 - 45 it will start if I pull it. But I wanted to check the valves better so I stated with I call the fluid test. That is make sure the valve is closed and spray some WD 40 or what on it to see if it holds. Well I did that and only one exhaust valve held and all intake valves held. So I popped off the valve from the #2 cylinder and inspected it and found some pitting in the seat. So I had the idea to LAP the valves, (couldn't hurt anything anyway since they were all out). So I LAPPED all the exhaust valves for now, they look a lot better now.

So Question, should I lap all the intake valves too while I'm at it or should I just move on. I must add, this is the cleanest motor I have worked on in a while. The cylinder walls look real nice but have a glaze on them so I a wondering if it doesn't start after the valve reconditioning if I should pop the pistons and hone and rering. That is the last thing I want to do though.

If there is anything I should do or ideas please let me know.

Thanks

Re: Trying to get a 48 started

Tue Jan 08, 2013 4:59 am

Lap the intake valves.

Rather than keep taking the head off the engine. Conduct an in tractor over haul. Drop the oil pan and plastigage the crankshaft journals. Push out the pistons. New rings and crankshaft inserts are relatively inexpensive.

Guessing, you will find excessive ring end gap and the oil control rings stuck.

Re: Trying to get a 48 started

Tue Jan 08, 2013 9:52 am

Are we all insane? Or just good people? How many parts tractors are now out there running because we couldn't bear the thought of scrapping them?

If you have what I had with my parts tractor, you have stuck rings to go with your stuck valves. Bearings and wrist pins are probably serviceable, even if not in spec.
Get the valves ground, then lap them to the seats, if you can find someone with a valve grinder. My cousin up the road has one - not everybody has that option available to them.

5098X Sealed Power/FPD set of rings is the cheapest out there. Find it under FP5098X, or FPD5098X or just 5098X. I got mine from Napa for about $30 delivered, but they can be found at TM, Rockauto, and Oreilly. The chrome sets will run $100 or more (FP5098KX). Oversize goes by 5098X20, 30, 40...
I also bought a flexhone. By far the best hone in the world. It's in the loaner tool crib for the asking.

Good luck....

Re: Trying to get a 48 started

Sun Jan 13, 2013 8:19 pm

Got the 48 started today, I pulled it around for about 10 mins and all it did was cough and jump and then it fired right up. I let it run for a bit and then it quit on me so I pulled it again but this time by myself (DANGEROUS). I got it started again and I jumped off my cub to hit the shifter and yea, I slipped and fell on the ice and it about got away but I was able hit the shifter. I got excited once it ran and so just had to keep it running for a bit more so I could determine what else is wrong. I was able to do so for about 30 mins then shut it down for a bit after I pulled it in the garage.

I looked over the few things I found and wanted to start it again and tried the hand crank and it took 3 tries and it was off and running. It runs pretty good, but the hydraulics do not work. I added oil and nothing happens when I move the lever. Is there a stuck valve inside the unit? I was going to try fixing it next?

I have put about $20 in this tractor and few days of time and it does run. I am excited about getting it running and it will most likely be a KEEPER. I think it would make a good cultivating tractor, if I can get the Hydraulics to WORK?

Thanks for the info from all. I did a compression check on all cylinders after I parked it for the night, I got around 90 to 110, and 110 being the cylinder I had nothing in before.

Sometime I guess you can't seem to let go?

Re: Trying to get a 48 started

Mon Jan 14, 2013 11:38 am

Leave the fill plug on the hydraulics open. It helps to prime the system if there is no vacuum being created.

When I refreshed the hydraulics in my '53, I had to add oil after the initial startup. The pump and lines hold about half the hydraulic system's capacity apparently, because it sucked the reservoir nearly dry right away. Refill and work the lever back and forth slowly.

If the tractor isn't making any funny noises around the pump or TC, you don't have a blockage. That's good.

Check the oil and make sure the tractor isn't "making oil." In other words, the amount of oil in the engine is not increasing. That means the pump is dumping the TC oil straight into the engine. Rebuilding the pump isn't a big deal, though.

Re: Trying to get a 48 started

Tue Jan 15, 2013 8:56 am

[quote="Jason (IL)"] I pulled it again but this time by myself (DANGEROUS). I got it started again and I jumped off my cub to hit the shifter and yea, I slipped and fell on the ice and it about got away but I was able hit the shifter.

PLEASE PLEASE DONT DO THIS AGAIN!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

We like to have you around for a while

Re: Trying to get a 48 started

Tue Jan 15, 2013 11:02 am

Jason (IL) wrote:...I let it run for a bit and then it quit on me so I pulled it again but this time by myself (DANGEROUS). I got it started again and I jumped off my cub to hit the shifter and yea, I slipped and fell on the ice and it about got away but I was able hit the shifter...


Mike in Louisiana wrote:PLEASE PLEASE DONT DO THIS AGAIN!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

We like to have you around for a while

:Dito:
Accidents happen by themselves often enough...don't help them happen! Remember the Circle of Safety????
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