Construction and other equipment - HD6E steering problems revisited

HD6E steering problems revisited

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Topic: HD6E steering problems revisited

Posted By: oljoe
Subject: HD6E steering problems revisited
Date Posted: 28 Jul 2011 at 12:04pm

This is a new chapter on the steering problem that I have with the HD6E. (see HD6E steering problems)

After relining the brakes, replacing the bevel gear a putting everything back together the dozer steered fine…..for about an hour. After it warms up the left steering clutch and the right brake start to be slow to engage, a little later the right clutch and the left brake does the same thing. If I throw the clutch out and hold the steering lever or the brake I can “feel” the brake engage. It’s like the oil takes time to get through the valves.

There are a couple of other things that I have noticed. If I run the throttle at about half it seems to work better or if the nose of the dozer is considerably lower they work a little better. I have been running it over filled as ac_sd suggested. I temporally removed the two filters from the canisters behind the battery boxes (that made it worse). HC6 Merv and AC Mel were both familiar with the problem so I am hoping that there is an answer out there somewhere.

Any suggestions?

Joe

Replies:

Posted By: oljoe
Date Posted: 01 Aug 2011 at 8:53am

Here is an update.

This weekend I ran the dozer for about 12 hours. It would be difficult to steer after about an hour. I read in the manual that there is a relief valve that is adjustable so I adjusted the valve, ran it for about 30 minutes at the end of the day and it worked fine. The next day I ran the dozer for about 45 minutes and the same old problem showed up again.

Here's where it gets interesting. I shut down the engine for about a minute and started it back. The steering and brakes worked fine. Every time it started acting up I killed the engine for 30 seconds to a minute and it steer again for awhile.

What do you all think?

Posted By: Coke-in-MN
Date Posted: 01 Aug 2011 at 9:01am

Wild guess , somehow your getting air into system on suction side of pump.

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Faith isn't a jump in the dark. It is a walk in the light. Faith is not guessing; it is knowing something.
"Challenges are what make life interesting; overcoming them is what makes life meaningful."

Posted By: gemdozer
Date Posted: 01 Aug 2011 at 11:10am

I remember you change your brake and bevelgear and you should still have some dirts in oil and after 15 minutes suction the streaner must be pluged or in the stering cluch valve she must have a piece off dirt inside and she is working bad.

Posted By: Mactractor
Date Posted: 02 Aug 2011 at 3:20am

A process of elimination now Oljoe by checking out each of the suggestions. I constantly hear of these problems with hydraulic steer HD6s. Whats got me beat is early HD11ep and HD11e have exactly the same systems as HD6 hydro steer but I`ve never heard of or experienced those tractors giving the same trouble except when the pumps are shot

Posted By: dadsdozerhd5b
Date Posted: 02 Aug 2011 at 7:08pm

definately a suction issue. once you shut it down, oil refills itself and away you go. could the oil be trapped somewhere and not able to get back to the suction and cause the cavitation? sounds like maybe something else is blocked on the suction side of the pump. i would pull the suction screen and recheck. the hd11 has to have a bigger transmission and then more oil storage leading to more oil for the pump to use. how about hooking up a small tank to the suction side of the pump and plumbing it into the bottom of the trans at the same level to give more oil storage? i am used to the older dry clutches, are these running in the oil or does the oil just work the steering assist? is the oil in the trans, bevel and steering clutches all common?

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HD5B, HD5G, (2) FARMALL A's, CUB. DO IT RIGHT THE FIRST TIME, IGNORE THE LAUGHTER. FLANNEL IS ALWAYS IN STYLE.

Posted By: Mactractor
Date Posted: 03 Aug 2011 at 5:40am

Clutches run in oil. HD6 trans, bevel gear, and clutches all one resevoir. HD11 clutches and bevel gear separate from trans so steering pumps on 11,s do not suck any more oil than 6,s do

Posted By: oljoe
Date Posted: 04 Aug 2011 at 1:36pm

Thanks for the replies everyone,

Coke, I think your guess is on the right track but I don’t know how figure out where the air is coming from.

Gemdozer, When I changed the bevel gear I also pulled the steering clutches, brakes and even the transmission. Everything was cleaned with a solvent sprayer air nozzle. With all of the work that went into that I made sure that it was clean enough to eat off of. It is possible that there still may be spec of dirt that got into a relief valve, but there is a relief valve for each steering clutch. I don’t think both valves would get contaminated at the same time.

Mactractor, I have also heard of a couple of other HD6s with the same problem.

Dadsdozerhd5b, The way the HD6 is set up there are 3 pumps at the front of the engine. One pump is to supply oil to the wet master clutch. This oil supply is completely separate from the steering, brakes and transmission. The two other pumps provide pressure to the steering and brakes. One is for the left clutch and right brake and the other is for the right clutch and left brake. They share one common supply. The oil dump for the valves is in the steering clutch compartment, oil then flows into the transmission where there is a screen on the supply line. The pump supply line has 3 sections of 1 ¼ steel pipe and a bolt on connector for each end, one on the transmission with a screen and one for the pumps. There are rubber hoses connecting them. 4 stainless steel hose clamps are on each section of rubber hose. I have checked the clamps and I am sure they are all tight.

When this thing starts to act up both clutches and brakes are slow to respond. The longer I run it (when the trouble starts) the longer the response time until the left clutch and right brake won’t work at all. The right brake and the left clutch will work but are really slow (sometimes a minute) to respond.

Posted By: Ages Cat
Date Posted: 04 Aug 2011 at 4:57pm

I have an HD6B and an HD6E. At one point I was convinced I needed power steering and brakes. After reading the posts on this tractor, my manual steering and brakes on my old tractors are just fine.

Posted By: dadsdozerhd5b
Date Posted: 04 Aug 2011 at 5:47pm

since the oil dumps into the steering clutch compartment and sucks out of the transmission, sounds like it is not flowing back into the trans correctly making the pumps starve. if the trans was out when you replaced the bevel gear, i wonder if the gasket for the trans is blocking an oil port stopping oil to the trans. anywhere to hook a line to allo more oil to flow? i cannot think of a place to hook it up but just a thought.

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HD5B, HD5G, (2) FARMALL A's, CUB. DO IT RIGHT THE FIRST TIME, IGNORE THE LAUGHTER. FLANNEL IS ALWAYS IN STYLE.

Posted By: dadsdozerhd5b
Date Posted: 04 Aug 2011 at 7:23pm

the more i think on this the wilder my ideas as to add another suction line, putting a small tank added in line to the suction with an extra hose in the top so as the pumps suck the oil out, it would pull it from the steering clutch housings, etc. i can see why they would dump the oil into the steering clutch housings to cool the clutches and also keep the oil circulating throughout the whole system. is there an extra plug low on the trans like a drain port or level check prt you could put another line in? how about overfilling the trans alot and see if it helps. would be great to be able to run it without one of the steering clutch covers off to see if it is keeping trhe oil back but too messy and would allow dirt in then. is the newer hd6 trans the same as the old hd5? i will look at my spares next time i get to them to look at the oil transfer holes.

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HD5B, HD5G, (2) FARMALL A's, CUB. DO IT RIGHT THE FIRST TIME, IGNORE THE LAUGHTER. FLANNEL IS ALWAYS IN STYLE.

Posted By: oljoe
Date Posted: 09 Aug 2011 at 8:24am

I broke a track rail this weekend so I’m down for a while. I chained it back together and limped back to the shop.

I guess I’ll drain the steering and transmission this week and take a look at the screen, suction lines and gaskets. I think I’ll replace all of the rubber hoses just to make sure none of them are leaking, clean the vents in the transmission and steering clutches and clean out the compartments again.

I’m going to drop the belly pan to make it a little easer to get to the lines. Is there anything else that I should check while I’ve got this thing down?

dadsdozer,

Thanks for the replies

The oil port from the steering clutch compartment to the transmission is about 1” by 2”. When I put the transmission back in I didn’t use a gasket. I used the red high temp silicone and was careful not to use too much. I’ve seen that stuff in the suction screen of too many car motors so I know what kind of a problem it will cause.

This thing should work the way it is designed, but I’m still open to suggestions.

Posted By: dadsdozerhd5b
Date Posted: 09 Aug 2011 at 9:17pm

is there that big of a hole in the trans to let the oil back in? is it the same trans as the hd5 and early hd6? maybe the turning gears is not allowing the oil back into the trans fast enough. i agree it should work as designed. keep digging, you will find it. there is a complete undercarriage on ebay now if you need it. a little expensive but new is not available so take what you can get.

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HD5B, HD5G, (2) FARMALL A's, CUB. DO IT RIGHT THE FIRST TIME, IGNORE THE LAUGHTER. FLANNEL IS ALWAYS IN STYLE.

Posted By: oljoe
Date Posted: 15 Aug 2011 at 10:38am

Here is the update. I got some help (from my brother who bought the dozer) to drop the belly pans. I finally got him to get dirty ha ha. I drained all of the oil. There was no metal on the magnets and the oil looked clean. Next I removed all of the steel suction lines and checked for leaks by plugging one end put air pressure in the other. There was a place on one line that had been braised but no leaks. I inspected the rubber hoses. They were a little soft but I didn’t see any evidence of any leakage. I got some new sections of rubber hose anyway just to be sure.

Then I pulled the screen. It was plugged with very fine fiber material, probably brake lining. There was a small area along the bottom that was not completely plugged. In the screen compartment of the transmission there was more of the same material that plugging the screen. I cleaned everything up and put it back together using the new rubber hoses. I ran the dozer for 7 hours yesterday and the steering worked the whole time.

I think what was happening was that the screen was partially plugged. When the pump was sucking oil the material floating in the oil would finish plugging the screen. When I stopped the engine the material would fall from the bottom of the screen and allow the oil to flow to the pump until it would plug up again.

Thanks everyone for all of the suggestions and help.