Replacing Seals On A Bobcat 743 Spool Valve

My Bobcat 743 has been leaking oil for quite some time, and recently it's become too hard to ignore. Inspecting the spool valve while it was running I could see that it was leaking oil out of the top valve.
The spool has two o-rings that need to be replaced. The only way to get to them is to pull the spool from the rear. In order to do that you have to remove linkages and hard lines.
The job took me about 14 hours or so, mainly because I had to go back and fix something. Pay careful attention to the direction the thrust washers go back on when you're reassembling the valve!
Bobcat O-Ring part #6646372

[@alanclarke1114]

Any one watching this who is thinking about doing this repair. DO NOT GO UNDER THE LIFT ARMS WITHOUT AN ARM STOP ON THE RAM .I have seen one fall due to a hydraulic failure and you wouldn't move quickly enough to avoid it. That strap over the beam is sketchy A.F to say the least . And I'm not a health and safety freak I do stupid crap ,I grind with safety squints

[@JSCorvette84]

Thanks so much for making this video! I was able to get my 751 valve fixed with the help of this. I didn’t have much experience with control valves and this helped me know what I was getting into. Thanks again!

[@gyffjogofl7676]

I'm glad you explained about the arm falling. It could have been real bad.

[@Ett1337]

743 Best Bobcat ever !

[@bobhornung8779]

Thx for the vid, this was a big help! I found you can bench test the float detent by just pushing it down (hard) on a table and it should stay in position...just be careful pulling it back out of detent (I put a rag around it to catch the balls if it pulls out too far). Luckily the lift valve is the easiest one to get to when you take another pass at it. I did mine with arms down & wasn’t too bad.

[@mitsosg7604]

Thanks for the video I had the same problems and now working perfectly

[@tf-lv4zu]

thought i was going to read about you in the obituaries

[@guitarslinger8633]

Nice M37 back there!...I got one too!

[@pulleyland2768]

Great job. Got same repair on same machine

[@goldcountryruss7035]

The 3rd unused spool is for an optional rear aux. hydraulic circuit. The 4th is front aux. hydraulic. I have a 743 and I will be servicing my valves in a few days. I will be cutting a rectangular hole in the chassis side with adequate room to access the front of the spools from the outside with the tires removed. After the repair I will bolt a cover plate over the new access hole.

[@edbeck8925]

You seem to be missing the brace that holds the arms up. You should always lock It in place before you start working. Your strap saved the day. But you should only have that as a back up.

[@bobcat8439]

Cut a pipe long way in half then put it around the cylinder ram then put hose clamps around the pipe to hold it together

[@joew5862]

I see that the bottom return hose from the valve body has been replaced did you replace it. I have one leaking and wondering how to get it apart.

[@juniorrackley2569]

It looks like the tires and wheels are larger on the front of the machine. I think this will cause problems since one will be turning faster than the other. I'm old it might just be my eyes. Good video thanks for making it.

[@yurimig253]

There is one more seal behind the spring inside tiny thing with a plastic piece.

[@rss608]

not sure about this, but doesn't the longer spool with the c clip go on the bottom??? could explain why the auto level is not working?

[@abcdefg3386]

Shouldn't the seals go in the notch in the housing first, and then put the spool in? how else are you gonna now the seal is in the notch?

[@cheriehudson2]

I removed the hydraulic control valve from a 743 Clark bobcat. Didn't label the hoses for reinstall. Any idea what goes where? I've googled for days and can't find a diagram.

[@pulleyland2768]

Wht is part # for rubber boots

[@rss608]

I'm facing the same thing, need to rebuild due to leaking orings in the valve body. 01 753G batt is on the opposite side so no access to the rear of the valve body, or at least it seems that way. question?: would it not have been easier to just remove the entire valve body? what was your reason for not just removing entire valve body? it amazes me that I have only 526 hours on the machine and I can't keep hydraulic fluid in it.....

[@JM-yx1lm]

What was the part number for the boots you have?

[@rexhavoc2982]

Why are you running the front tires backwards?

[@markvylonis]

Ok , I see you got the plugs and caps on Amazon, How much ? And who was the supplier ? Thanks for your answer.

[@jrodjared]

Mark Vylonis $32.42. Speedway Motors. Click the link brings you right to it.

[@markvylonis]

Same leak on my 751, where did you get those red plugs at ? for temporary use?

[@jrodjared]

Mark Vylonis Amazon Plastic AN Fitting Cap and Plug... www.amazon.com/dp/B07B8TV8XX?ref=ppx_pop_mob_ap_share

[@pokeypeter]

Another video shows the third one down goes to a line back by the motor

[@MuhammadAfzal-jm6cw]

Ok 👌👌👌

[@mikemansfield270]

Check your spools for pittingjust a tip!

[@johnbauknight6609]

S

[@bobcat8439]

Should be a access panel under Neath

[@wovenwire_4.513]

I want to cut out a access hole in that are area. I did on my pontoon with I/o to access starter. Its works great.

[@mikemansfield270]

No need to have the bucket in the air put it on the ground

[@user-ue8no1ys8r]

Михаил Задорнов говорил - Нууу, тупые))). Кто хоть немного в теме по спецтехнике - поймёт... Господин не очень отдупляет: ни в принципах работы гидравлической системы, ни в элементарных понятиях "слесарного мастерства"))). Но не смотря ни на что ведь победил... Очень двоякое впечатление от ролика осталось... Вроде и не отдупляет особо этот гражданин, да и кривожопый ещё, а справился... Молодец👍. А Задорнов рулит 🤟 , по-любому!

[@youngrevival9715]

I took this valve out it was a nightmare

[@georgemesz7850]

angle iron cut too place in lift cylinder.will save your ass instead off replacing your roof

[@mikemansfield270]

I did a job on a 743 pulling out the control valve and changing most of the hard lines! The motor needs to come out and pay close attention to the hard line routing! A tip make sure your very bottom line to the valve is installed before you put the valve back in! It's the rubber line all the way to the bottom! Be forewarned it's a bitch of a job and bobcat should be shot for that kind of design! Also pull the plastic fan shroud forward from the bottom or the valve isnt coming out! Again horrible design!!!

[@mikemansfield270]

Biggest piece of junk going!! Avoid these machines at all costs

[@mikemansfield270]

Not your fault bud just a horrible design like the rest of the machine!!

[@mikemansfield270]

No room to get your hands in or swing wrenches!! Very poor design!

[@portagepete1]

The newer ones have a turbo=less room and more to go wrong.

[@parabot2]

Bobcat should be ashamed of this Design , total rubbish to work on ( If you can get access to even use the overpriced parts )

[@joebrusge8819]

you should not own one if you can understand proper safety. just saying