Hello and thanks to any/all helpful information anyone can provide regarding the below issue- I recently bought a 1989 742 with the Ford 4cyl engine. I bought it on the cheap from a homeowner because it was leaking hydraulic oil pretty badly at the time and he could not figure it out. That same day, I took it to a heavy machinery repair shop because I figured I would have them go through the machine and see what it needed and see whether it was worth it to fix, or I could always sell it for around what I paid and move on. It ended up just being a hydro line that was busted, just in a hard to reach spot, which was good. After looking the rest of the machine over, we went ahead with the following work- (Sorry for the long post, but I figured I should include the backstory and recent repairs for context) Items repaired/replaced- spark plug, wires, cap, rotor, points, condenser one lift cylinder was fitted with a seal kit new o-rings for relief and load valves on lift circuit Basically, got a tuneup on the engine and then the seal kit and o-rings on valves because the bucket had a pretty horrible drift and would not stay up. *They also emptied the gas tank because they said it was bad gas and pointed out that the oil cap on top of the engine should be replaced because it looked burnt/warped but left that to me to fix, as at the time there were no signs of issues coming because of it. So, after 3 weeks of being at the shop (they took their time, and i was in no rush) I picked up the 742 today and brought it back to my house. Engine seemed to be running strong, needed choke for about a minute, then could back it off while bringing up the RPMs with the throttle and it was running/sounding good with no sputtering, etc once it was warmed up. Hydraulics seemed decent, but I will say that they whined a bit until i went full throttle, then they ran pretty decent. seem to whine a little while sitting still, and I can very slightly move the hand controls to spots where they will stop whining, so i think this is probably just a linkage adjustment (but let me know what you think). I ran the machine pushing a mound of dirt I wanted back off a tree line in a small field. Everything seemed like it was working pretty well. I did this for about 30 minutes when it began sputtering and then died. I thought it was my electric fuel pump at first, because it is wired to an in/out choke-style mechanism back by the seat and it is easy to bump with your leg (this was a feature the homeowner added which he admitted was not his best design). After seeing that the fuel pump had not stopped running, I tried starting it 2 or 3 times with no success. I then checked the engine, and I have no "proof" so to speak, but it seemed hotter than I think it should be. Not positive, but it looked like there was wiring that may have shut the engine off due to overheating. the only thing i noticed was a slow drip of gas (1 drop every 3-4 seconds) from the hose that runs from the air filter to the carb. everything just seemed HOT. Coolant overflow showed fluid, so I don't think I am low there. I let it sit about 30 minutes and then started it up, and it seemed to run fine again, but I figured it would overheat and i didnt want to cause any permanent damage, so I drove it over to my gravel driveway and parked it for further evaluation. I went back out to the machine a couple of hours later (this evening) and started it up to see if I could notice anything else. One thing i found very strange was that it would only run if the choke was wide open, which was not the case earlier today. I let it run and while it was running I went back to look at the engine and I notice the oil cap that was warped and burnt looking is now showing 2 distinct holes on it where smoke is shooting out.... Would this cause the engine to only run if the choke is all the way out? What would cause this? Is this just a symptom of the overheating issue I am having or could this be causing my problem? My guess is something else is wrong, since this oil cap looked burnt/warped at the shop, so it was probably like this way when I bought it, but I didnt notice it then. (yes, my mistake, I am no mechanic) *We checked the engine oil at the repair shop a week or so ago and the mechanic said it looked good, and was not low. I did not mess with it yet, although I was planning to do an oil change this weekend. Also, I have a feeling that the hydro fluid is low, although they supposedly added oil when it was in the shop. Again, sorry for the novel, but I figure the more info I can include, the easier it may be for someone with experience to provide some helpful insight. Thanks again in advance for any tips on what I need to check to see if I can get this engine running right again.
Help Support SkidSteer Forum:
Not an issue for the novel, the more info the better.
First off, the steering adjustment for neutral to prevent the noise when not moving:
http://users.tpg.com.au/tazza_/Steering Adjustment.jpg
Now the engine, the smoke from the oil cap, it almost sounds like the breather tube is plugged? check to see if there is a hose from the rocker cover to the inlet manifold near the carb or another one to atmosphere. The smoke could just be blow-by, the more hours on an engine, the more wear, the more blow-by you will get.
I'm not loving the fuel drip at the air filter, it sounds like the float is not working, flooding or something else causing the leak.
First off, the steering adjustment for neutral to prevent the noise when not moving:
http://users.tpg.com.au/tazza_/Steering Adjustment.jpg
Now the engine, the smoke from the oil cap, it almost sounds like the breather tube is plugged? check to see if there is a hose from the rocker cover to the inlet manifold near the carb or another one to atmosphere. The smoke could just be blow-by, the more hours on an engine, the more wear, the more blow-by you will get.
I'm not loving the fuel drip at the air filter, it sounds like the float is not working, flooding or something else causing the leak.
Tazza is all good w/ the creep adjustment except.........the round discs that the links stop against get flat spots worn into them and they won't turn over to remedy the problem by presenting a fresh wear surface. The good part is they are cheap......get a new set and follow the diag above to install/adjust. [DANGER-All 4 wheels off the ground while you run it to adjust.] Fuel:If it has been run with ethanol bearing fuel the fuel tank pickup will be toast. (Replaced mine in Oct18.) This generates a ton of rust that flakes off into the tank. Everything downstream will have the rust in it. Your having to run it full choke is the exact symptom. The fix is pretty cheap if you are handy, except for the fuel pickup if you can't salvage it. They are $255.00 US. A carburetor gasket set and owning a number drill set to clear all the jets and passages is the cheap part. Best to lift the ROPS and take out the fuel tank. It is a poly tank so pour out the gas and pour in a qt of water based solvent and a qt of water and a generous handfull of clean gravel. Then shake, shake, shake to agitate the rust loose. (I use Greased-Lightning.) Invert and shake out the rocks. Wash with water hose. You only have a 2 3/4" hole to work through. It will come clean as new. Slosh a qt of gas in it to get the last bit of water. Keep away from the ethanol fuel and it will run a long time. Blowby: These engines came with poor piston rings and in some cases after they stuck they caused the pistons to scuff. They only have a crankcase breather, not a PCV setup, so you will see the blowby. You can go a long way to free up/clean up things with any number of products without opening up the engine. Just change the filter with each pass of oil change/ solvent mixture. (Marvel Mystery Oil, Seafoam, ATF will all work as a 20-30% additive to 30 wt oil. Run for<10 hrs and change.) You can check the compression and if all cyls are even you can use it a while. They are pretty low compression engines anyway. Good luck, they are solid tractors. Had mine since'84. -Dick
Tazza & craigb93 - thank you for the very helpful information. it is much appreciated. I got out to the 742 last evening after work and added some "Rislone high mileage compression repair with ring seal" to the oil. I had just changed the oil this past weekend, so I had 4 qts of 10W30 and a new oil filter on it. After I added the Rislone, I ran the engine for 30-45 minutes at various RPMs to give it a nice chance to mix the treatment with the oil. I cant say that I noticed much of a difference, if any, to the smoke coming out of the breather portion of the oil cap. Just as additional information, I would guess there are some decent leaks on the exhaust manifold gaskets, and my muffler is also toast. it is completely rusted and im sure will look like Swiss cheese when I get around to removing and replacing it. The engine itself seems to run decent, and i cant say why, but I do not need the choke any longer. I am not sure if the choke line was just stuck the last time or what, but it hasnt been an issue the past 2 times I started it up. I will say that when doing the oil change I also changed out the in-line fuel filter, so not sure if that had anything to do with it, but my hunch is no. One thing that I have noticed is that there seems to be some light "putting" or what I would maybe call light backfiring every couple of seconds. nothing crazy, but enough to hear when you are back by the engine when it is running and you can sense a little decrease in power for a split second when it happens. Do you think this is a symptom of the rings? Maybe I need to pull the carb or at least hit it a few times with a carb cleaner? I know that before I bought it, the machine sat for awhile and would go long periods without being ran, which I know is a death sentence for the carb. Another reason I thought of could be the lack of back pressure due to the shot muffler- what do you think? In terms of blowby, what is considered an acceptable amount, and when is it to the point where you either need to overhaul the engine or just move on altogether? I will be honest, I am getting to the point with the repairs/upgrades I would like to do to make it a dependable machine and I see $$ everywhere I turn. This is more of a handy tool for a small family farm and not a necessity, although I have tons of chores I could get done with it. Trying to determine whether to keep plugging along with repairs, or if I need to cut my losses and pass it along to someone with more time on their hands to properly care for the engine/do it themselves and not have to spend a fortune on it. the one good thing is that the hydraulics seem strong and are not drifting like they were when I bought it. Your honest thoughts and opinions are appreciated as always. thanks,
The filter change restored fuel flow is why the choke is now not needed. It will be ok until the new filter fills w/ rust. Maybe you will get lucky and clear enough rust by repeating the filter change if the problem recurs. ** Bobcat made a new Centering Spring (&washer) that helps a bunch w/ creep. It is a larger diameter spring that does not get gummed up in debris, under $10.** The ring freeing treatment won't be immediate. Add some more solvent but maintain oil level only full, not overfull. ** I have a good used muffler when you get that far.
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- Dec 17, 2009
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Also make sure your ignition timing is correct. If it's off some it can cause overheating issues. Another thing could be your condensor in your distributor acting up. When I bought my second 732 (same engine as your 742) it would not run right even though everything in there looked new. On my other 732 the condenser was so prone to failure we always stocked a spare in the shop. On my second one I replaced the condenser and points with a pertronix electronic ignition and it made a world of difference!
I have a 742 that seemed to run way too hot when I bought it. I claim NO expertise but, I found a couple of things that helped the issue. (1) if you have any exhaust leaks in the engine compartment, fix them. Mine had the exhaust manifold gasket bad, and blowing right on the radiator hose. Also some of the cooling fan intake air comes from the engine compartment, extra heat from the exhaust leak didn't help. (2) My coolant was mostly water, changing to 50% antifreeze/water helped. (3) if the radiator cap, coolant recovery bottle and hose isn't 100% correct, you will get air in the system. That had to be fixed. Mine also makes some odd hydraulic noises when stopped, and loses/leaks a little of the hydraulic oil. The engine has some, but not excessive blow by for its age. Even with those issues, it beats not having a Bobcat by a great deal.
Thanks to all for the replies and helpful information. it took me a while to get back to it because of other obligations but now that I had a few days off around christmas, i got to get out and run the thing. have not had issues with the engine or overheating, other than the blowby that I think is never going to get any better. I will just keep the oil full and some treatment in there to help keep it as lubed as possible without putting molasses in there. We have a long driveway (around 200 yards?) that had gotten really beat up with potholes due to all the rain we have been getting here in VA. I ran the 742 continuously for about 2 hours tearing up the potholes and then smoothing the driveway back out and I had no issues. I then ran it a couple days ago back in the woods to cut a trail through the woods (knocking down small trees and ripping them up) so that I could get to some fallen trees that I had cut up a couple of months ago to bring up closer to the house for firewood. I will say that for a bobcat on the smaller end of the power spectrum, this thing is still impressive! After running it 2-3 times over the past week with no issues, I am starting to have some renewed faith in it, and am back to making some small/easy upgrades, starting with 2 new tires on the left side (right side is fine) and then i want to get a muffler because mine is rotted out and I am worried small pieces of rust may find their way from the muffler back into the manifold. There will be plenty of other upgrades/repairs needed, but for the moment, I am going to enjoy a working machine and actually get some work done with it.
Hey craigb93, I would definitely be interested in that muffler. mine is completely rotten. Do you happen to be in the VA area, or would you ship it? Let me know how much you are looking to get for it and we can hopefully get it done. would beat buying one for $120 online! thanks,
