| Author |
 Topic Search  Topic Options
|
Hillmann 
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
 Post Options
 Thanks(0)
 Quote  Reply
 Posted: 22 Sep 2022 at 9:37pm |
 steve(ill) wrote:
I dont think any of us condone building up a motor that is way out of spec.... But as you said there are a LOT of 75 year old tractors with worn out motors that are still running today.. Considering it is out in the field, i think i would assemble ASAP with the rod bearings, forget the cam, see what kind of oil pressure you got and go for it ..... Get your shed built and redo the motor over the winter.
If your PUMP is good, you really dont need much oil pressure, just a lot of FLOW....... still question what ORIGINALLY caused the problem.
Might be worth putting a THICKER oil in to try to fill up some of the clearances and retain oil film.
|
I don't know what caused the pump to stop working. I put the mower on, added a quart of oil then made three or four rounds mowing. Then shut it down to make sure nothing on the mower vibrated lose and then made a few more rounds. After checking everything and restarting I had to have the throttle one notch higher than I did at first. I watched kept a close eye on the temp gauge because early in the summer when working it hard it would start to loose power when it was up to temp(condenser, plugs and adjusting valves mostly fixed that). It never got much above 170 so I wasn't too concerned about the need to have the throttle a bit higher. It stalled out going up a small hill. When I tried to restart it is when I first noticed it wasn't building oil pressure when cranking it. I took the oil filter and valve cover off to confirm it wasn't pumping oil instead of the gauge just not working.
My guess is when I shut the tractor down to check that everything was tight the check valve on the oil pump got stuck open and the pump lost prime. I don't watch the pressure gauge that closely and I must not have noticed it didn't have pressure. Once I primed the pump through the filter tube it pumped oil just like it should while cranking it with the starter.
The screens on the oil pick up were clean of debris when i pulled the oil pan so I don't know if something got stuck in the check valve or just build up over time was finely enough to hold the valve open. Now that I have the engine apart it looks like the last person to be in there was a fan of silicone. My first thought was a chunk of that got stuck in the valve but it would have had to get past the mesh on the oil pickup.
|
 |
|
Sponsored Links
|
|
|
steve(ill)
Orange Level Access
Joined: 11 Sep 2009
Location: illinois
Points: 77846
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 9:06pm |
I dont think any of us condone building up a motor that is way out of spec.... But as you said there are a LOT of 75 year old tractors with worn out motors that are still running today.. Considering it is out in the field, i think i would assemble ASAP with the rod bearings, forget the cam, see what kind of oil pressure you got and go for it ..... Get your shed built and redo the motor over the winter.
If your PUMP is good, you really dont need much oil pressure, just a lot of FLOW....... still question what ORIGINALLY caused the problem.
Might be worth putting a THICKER oil in to try to fill up some of the clearances and retain oil film.
Edited by steve(ill) - 22 Sep 2022 at 9:09pm
|
|
Like them all, but love the "B"s.
|
|
Hillmann
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 8:52pm |
steve(ill) wrote:
YEA.... i just figured out that you have the head off, since you said you could see the notch on the piston tops....
Sounds like you are working out at the farm ? If the motor was out and HOME in the garage, you might have more time and easier job to overhaul ?
The oil pump drives off the back of the cam shaft.. If you pull the motor, check the pin drive in the shaft. |
At the moment it is out in the hayfield where it stopped running. Unfortunately I don't have any place to work on it at home other than the living room. And no work shop at the farm either.
If I end up pulling the entire engine I will want to do a full restoration on it, which I would like to do, just not now when I should be baling hay. So at the moment I just want to get it back up and running for another 20-30 hours and then I will have all the time in world to work on it this winter.
My project for next week was going to be to put up a shed that I tore down and moved to the farm so I have a place to work in the winter, but now my project for next week is to get the tractor running and bale hay.
|
|
steve(ill)
Orange Level Access
Joined: 11 Sep 2009
Location: illinois
Points: 77846
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 8:40pm |
YEA.... i just figured out that you have the head off, since you said you could see the notch on the piston tops....
Sounds like you are working out at the farm ? If the motor was out and HOME in the garage, you might have more time and easier job to overhaul ?
The oil pump drives off the back of the cam shaft.. If you pull the motor, check the pin drive in the shaft.
|
|
Like them all, but love the "B"s.
|
|
Hillmann
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 8:37pm |
steve(ill) wrote:
probably hard to get a good measure of bearing wear with the cam installed.. The pushrods and rocker arm are pushing DOWN from above so you will not notice much movement by hand ............ if your going to pull the cam, i would suggest pulling the motor and turning it upside down / rocker arm off / push rods out. |
The head is off. Just the camshaft and crank shaft are left in the block at the moment so the .015 isn't a super accurate measurement because I only measured the front bushing but it is close.
|
|
Hillmann
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 8:35pm |
Alex09(WI) wrote:
Hillmann wrote:
The camshaft has .015 of play up and down. And none I can measure side to side at the front of the engine. It got too dark to measure the play at the back of the engine.
I am not sure if that .015 is from running it without oil or from 80 years of the pushrod putting down force on it.
I have to check the manual this evening to see how far out of spec it is. |
The spec for oil clearance for the cam is .002"-.004", .015" is way out of spec. But given your situation, you will have to run it the way it is.
Where are you in WI? I am between Green Bay and Wausau and run an unofficial Allis-Chalmers dealer. I have some .0025" rod bearings here that will work better than STD for the specs you measured. I also have gaskets, reground crank and lots of other parts to get you back going asap! I don't have a running engine to drop in though.
|
Rice Lake.
What do you mean by .0025 rod bearings? Are they oversized by that amount?
I would be interested in getting parts from you if you have them in stock.
At the moment I need: a head gasket,
thermostat housing gasket, (the one between the housing and the head)
oil pan gasket,
timing cover gasket,
and a governor cover gasket.
As well as the connecting rod bearings and crush shims.
It feels like I am forgetting something in that list but I don't have the tractor here to look at and see what it is.
I was pretty sure .015 was way out of spec, but in your experience do you think an old, well used engine can get that worn and still run or would you guess that most of that is from running without oil?
|
|
steve(ill)
Orange Level Access
Joined: 11 Sep 2009
Location: illinois
Points: 77846
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 8:33pm |
|
probably hard to get a good measure of bearing wear with the cam installed.. The pushrods and rocker arm are pushing DOWN from above so you will not notice much movement by hand ............ if your going to pull the cam, i would suggest pulling the motor and turning it upside down / rocker arm off / push rods out.
|
|
Like them all, but love the "B"s.
|
|
Alex09(WI)
Orange Level
Joined: 15 Mar 2012
Location: CECIL WI
Points: 1698
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 8:30pm |
Whether you remove the cam or not, your oil clearance from the cam to the cam bearings is too much at .015". You will lose lots of oil pressure there. The only way to remedy that is to remove the cam and replace the cam bushings. You may need to go to 0025" undersize bushings on the cam also.
If you take the block out of the tractor, then you may want to consider just swapping out the crank also.
|
|
www.awtractor.com
A&W TRACTOR 920-598-1287
KEEPING ALLIS-CHALMERS IN THE FIELDS THROUGH THE 21ST CENTURY
|
|
Hillmann
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 8:22pm |
At this point all that is still in the block is the crank, cam and tappets, magneto and oil pump.
When I tried to pull it it was getting dark so I didn't try very hard but there was no end to end play with just hand pressure. I assumed I wasn't hitting the tappets yet because I figured there would be at least some play before they starting giving resistance. I'll have more time tomorrow to work on it.
Although at this point I think I am only a few bolts away from removing the block from the torque tube so if the cam has toooo much play I may just pull the engine completely.
|
|
Alex09(WI)
Orange Level
Joined: 15 Mar 2012
Location: CECIL WI
Points: 1698
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 8:15pm |
Hillmann wrote:
The camshaft has .015 of play up and down. And none I can measure side to side at the front of the engine. It got too dark to measure the play at the back of the engine.
I am not sure if that .015 is from running it without oil or from 80 years of the pushrod putting down force on it.
I have to check the manual this evening to see how far out of spec it is. |
The spec for oil clearance for the cam is .002"-.004", .015" is way out of spec. But given your situation, you will have to run it the way it is.
Where are you in WI? I am between Green Bay and Wausau and run an unofficial Allis-Chalmers dealer. I have some .0025" rod bearings here that will work better than STD for the specs you measured. I also have gaskets, reground crank and lots of other parts to get you back going asap! I don't have a running engine to drop in though.
|
|
www.awtractor.com
A&W TRACTOR 920-598-1287
KEEPING ALLIS-CHALMERS IN THE FIELDS THROUGH THE 21ST CENTURY
|
|
steve(ill)
Orange Level Access
Joined: 11 Sep 2009
Location: illinois
Points: 77846
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 8:06pm |
all of the cam followers set on the cam and the pushrods set on top of that, and the rocker arm on top of the HEAD pushes down on everything.... NO, you can not just pull the cam out the front... It normally takes some effort when the motor is in the engine stand, upside down....
your getting in pretty deep when you pull the cam out...
Edited by steve(ill) - 22 Sep 2022 at 8:10pm
|
|
Like them all, but love the "B"s.
|
|
Hillmann
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 8:03pm |
To remove the cam does it just pull out the front of the engine?
It was getting dark when I got to that point so I just tried to give it a small pull and when it didn't come out I assumed there was more to getting it out.
|
|
Hillmann
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 7:58pm |
steve(ill) wrote:
If you know you are going to have excess clearances and you want more oil flow / spray to the bearing, you could block off the filter and get an extra 15% more flow internal... I would retain the pressure gauge so you can see what you really got, and look for pressure loss ( like the original problem). |
There are two holes on the tube going into the filter, one on the tip and one near the tip but on the side. My thought was I if I could find a screw that fit snug in one of those holes I could use it to temporarily block the flow. Another option was a piece of thick shrink tube to block the hole on the side of the pipe.
I have to do some reading in the manual to figure out how to get the cam out and the cam bearings.
|
|
Hillmann
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 7:55pm |
|
At this point I got to the cam shaft but don't know how to get it out so have to look at the manual to figure it out. I figured measuring the play in place will start to give me an idea of how bad it is.
|
|
steve(ill)
Orange Level Access
Joined: 11 Sep 2009
Location: illinois
Points: 77846
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 7:43pm |
|
If you know you are going to have excess clearances and you want more oil flow / spray to the bearing, you could block off the filter and get an extra 15% more flow internal... I would retain the pressure gauge so you can see what you really got, and look for pressure loss ( like the original problem).
|
|
Like them all, but love the "B"s.
|
|
steve(ill)
Orange Level Access
Joined: 11 Sep 2009
Location: illinois
Points: 77846
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 7:32pm |
you are not going to see much on the cam unless you pull it out...
getting the right clearance on the bearings with the shims is most important.
|
|
Like them all, but love the "B"s.
|
|
Hillmann
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 7:28pm |
|
The camshaft has .015 of play up and down. And none I can measure side to side at the front of the engine. It got too dark to measure the play at the back of the engine.
I am not sure if that .015 is from running it without oil or from 80 years of the pushrod putting down force on it.
I have to check the manual this evening to see how far out of spec it is.
|
|
Hillmann
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 6:13pm |
|
I am out at the farm measuring the journals on the crankshaft. Three of them are measuring at 1.934 to 1.932.
The fourth is 1.929 to 1.931.
I tried to measure each one in 8 different spots to get a somewhat accurate idea of how warn they are but with the crank still in the tractor it is hard to get measurements on all of them.
The standard bearings are for 1.937. I think I will order standard bearings and crush shims and they should fit even if I have to shorten the bearings as the manual suggests in situations where a proper fix isnt possible.
I need to take a closer look at the cam shaft yet.
|
|
Les Kerf
Orange Level
Joined: 08 May 2020
Location: Idaho
Points: 620
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 5:29pm |
Hillmann wrote:
Les Kerf wrote:
Any engine that lost oil flow long enough to melt the babbit out of the rod bearings will have debris scattered throughout the rest of the engine as well.
Only the most desperate need would induce me to not do a complete teardown and thorough cleaning of that engine, even if it meant eating beans for a month.
|
It isn't a money issue, it is more of a "I don't have enough hay for the winter yet" issue.
|
That qualifies as desperate need in my book. Clean it up best you can and git'er done. Best wishes 
|
|
TomC
Orange Level Access
Joined: 24 Nov 2017
Location: Hillsboro, MO
Points: 1544
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 5:04pm |
|
I don't know where in Wisconsin you are but there are several on craigslist ranging from $3,500.00 and down that look pretty good, buy another one, finish your hay up and rebuild the B over the winter, then you have two of them to use,, if I had it my way I'd have a tractor for every implement.
|
|
Hillmann
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 4:45pm |
Les Kerf wrote:
Any engine that lost oil flow long enough to melt the babbit out of the rod bearings will have debris scattered throughout the rest of the engine as well.
Only the most desperate need would induce me to not do a complete teardown and thorough cleaning of that engine, even if it meant eating beans for a month.
|
It isn't a money issue, it is more of a "I don't have enough hay for the winter yet" issue.
|
|
Hillmann
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 4:43pm |
steve(ill) wrote:
corbin brings up a good question... WHY did you loose pressure ? Normally the PUMP does not just QUIT PUMPING , and now it is OK ? Possibly the pin drive broke ? Or the filter is WRONG ? or the 1/4 inch tube up the center of the filter is GONE ? Or the suction screen in the oil pan was plugged with crud ?
|
I think the check valve in the pump is what caused the pump to stop working. When I prime it it works fine.
|
|
Hillmann
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 4:41pm |
corbinstein wrote:
I'll add my .02c. Check the filter for the little "Stand Pipe" up inside it that's part of the filter Base housing. Someone should be able to post an image please. If that is missing, don't run it until you block off the filter infeed line, or replace the pipe. Otherwise, it'll continue to starve the engine if it is missing.
|
The pipe is in there and it is the correct filter. My guess is the check valve on the pump is damaged. When I primed the pump it worked began working again.
|
|
Les Kerf
Orange Level
Joined: 08 May 2020
Location: Idaho
Points: 620
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 10:24am |
|
Any engine that lost oil flow long enough to melt the babbit out of the rod bearings will have debris scattered throughout the rest of the engine as well.
Only the most desperate need would induce me to not do a complete teardown and thorough cleaning of that engine, even if it meant eating beans for a month.
|
|
steve(ill)
Orange Level Access
Joined: 11 Sep 2009
Location: illinois
Points: 77846
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 8:52am |
corbin brings up a good question... WHY did you loose pressure ? Normally the PUMP does not just QUIT PUMPING , and now it is OK ? Possibly the pin drive broke ? Or the filter is WRONG ? or the 1/4 inch tube up the center of the filter is GONE ? Or the suction screen in the oil pan was plugged with crud ?
|
|
Like them all, but love the "B"s.
|
|
corbinstein
Orange Level
Joined: 31 Jul 2014
Location: Oklahoma
Points: 796
|
Post Options
Thanks(0)
Quote Reply
Posted: 22 Sep 2022 at 6:20am |
I'll add my .02c. Check the filter for the little "Stand Pipe" up inside it that's part of the filter Base housing. Someone should be able to post an image please. If that is missing, don't run it until you block off the filter infeed line, or replace the pipe. Otherwise, it'll continue to starve the engine if it is missing.
|
|
steve(ill)
Orange Level Access
Joined: 11 Sep 2009
Location: illinois
Points: 77846
|
Post Options
Thanks(0)
Quote Reply
Posted: 21 Sep 2022 at 10:18pm |
main and rod bearings are SHIMMED for clearance....
|
|
Like them all, but love the "B"s.
|
|
steve(ill)
Orange Level Access
Joined: 11 Sep 2009
Location: illinois
Points: 77846
|
Post Options
Thanks(0)
Quote Reply
Posted: 21 Sep 2022 at 10:09pm |
"splash lube" was probably not the best term to use... The OIL PUMP is mounted to the back of the cam shaft... The pump output is 85% down the hollow cam shaft and 15% goes OUT the 1/4 inch pipe, thru the bell housing , thru the oil FILTER, and DUMP to sump..
The 85% of the pump output goes down the hollow cam.. Cam has holes in it that point at the bottom of the pistons.. Oil SHOOTS out the holes at the piston, onto the wrist pin, and drips down onto the connecting rod bearings.
The cam also has holes in it to lube the 3 cam bearings directly... and there are 3 passage ways to the mains , from the cam, to lube the mains directly.... You maintain about 10- 15 psi in the system at the FILTER... The filter is stuffed with cotton and has HIGH restrictions (backpressure)... If the filter center tube is gone, or the filter is paper instead of cotton, you might have 50% of the oil LOST thru the filter and back to sump.. That is stealing FLOW from the hollow cam shaft...
Edited by steve(ill) - 21 Sep 2022 at 10:20pm
|
|
Like them all, but love the "B"s.
|
|
MACK
Orange Level
Joined: 17 Nov 2009
Points: 7664
|
Post Options
Thanks(0)
Quote Reply
Posted: 21 Sep 2022 at 9:06pm |
|
My guess is bearings started coming apart, then bearing parts got in oil pump. As I always say, (no short cuts) might as well do it right. MACK
|
|
Hillmann
Silver Level
Joined: 02 Jun 2014
Location: Wisconsin
Points: 206
|
Post Options
Thanks(0)
Quote Reply
Posted: 21 Sep 2022 at 9:04pm |
steve(ill) wrote:
also note that the connecting rods dont all go in the same way.. Two face the cam and the other two the opposite way... Bearing on the rod is OFFSET one way to get clearance by the center Main Bearing.
#1 MAIN has a thrust built into the bearing.. You might check END SHAKE of the crank and make sure it is not excessive... suppose to be around .005 inch. |
I kept them all facing the direction they were when the came out of the engine. However I think the front one may have been in backwards. All the pistons have a small notch in the skirt and on the rear three that notch was facing the front. On the front piston it was facing the rear. I don't know if that notch is supposed to be lined up in a specific direction(I know a similar notch matters on two cycle engines)
|
|
